Full Text Available UNLABELLED: Restricted sleep duration among young adults and adolescents has been shown to increase the risk of morbidities such as obesity, diabetes or accidents. However there are few epidemiological studies on normal total sleep time (TST in representative groups of teen-agers which allow to get normative data. PURPOSE: To explore perceived total sleep time on schooldays (TSTS and non schooldays (TSTN and the prevalence of sleep initiating insomnia among a nationally representative sample of teenagers. METHODS: Data from 9,251 children aged 11 to 15 years-old, 50.7% of which were boys, as part of the cross-national study 2011 HBSC were analyzed. Self-completion questionnaires were administered in classrooms. An estimate of TSTS and TSTN (week-ends and vacations was calculated based on specifically designed sleep habits report. Sleep deprivation was estimated by a TSTN - TSTS difference >2 hours. Sleep initiating nsomnia was assessed according to International classification of sleep disorders (ICSD 2. Children who reported sleeping 7 hours or less per night were considered as short sleepers. RESULTS: A serious drop of TST was observed between 11 yo and 15 yo, both during the schooldays (9 hours 26 minutes vs. 7 h 55 min.; p<0.001 and at a lesser extent during week-ends (10 h 17 min. vs. 9 h 44 min.; p<0.001. Sleep deprivation concerned 16.0% of chidren aged of 11 yo vs. 40.5% of those of 15 yo (p<0.001. Too short sleep was reported by 2.6% of the 11 yo vs. 24.6% of the 15 yo (p<0.001. CONCLUSION: Despite the obvious need for sleep in adolescence, TST drastically decreases with age among children from 11 to 15 yo which creates significant sleep debt increasing with age.
van Schrojenstein Lantman, Marith; Mackus, Marlou; Roth, Thomas; Verster, Joris C|info:eu-repo/dai/nl/241442702
INTRODUCTION: An evening of alcohol consumption often occurs at the expense of sleep time. The aim of this study was to determine the relationship between total sleep time and the duration and severity of the alcohol hangover. METHODS: A survey was conducted among Dutch University students to
Frase, Lukas; Piosczyk, Hannah; Zittel, Sulamith; Jahn, Friederike; Selhausen, Peter; Krone, Lukas; Feige, Bernd; Mainberger, Florian; Maier, Jonathan G; Kuhn, Marion; Klöppel, Stefan; Normann, Claus; Sterr, Annette; Spiegelhalder, Kai; Riemann, Dieter; Nitsche, Michael A; Nissen, Christoph
Arousal and sleep are fundamental physiological processes, and their modulation is of high clinical significance. This study tested the hypothesis that total sleep time (TST) in humans can be modulated by the non-invasive brain stimulation technique transcranial direct current stimulation (tDCS) targeting a 'top-down' cortico-thalamic pathway of sleep-wake regulation. Nineteen healthy participants underwent a within-subject, repeated-measures protocol across five nights in the sleep laboratory with polysomnographic monitoring (adaptation, baseline, three experimental nights). tDCS was delivered via bi-frontal target electrodes and bi-parietal return electrodes before sleep (anodal 'activation', cathodal 'deactivation', and sham stimulation). Bi-frontal anodal stimulation significantly decreased TST, compared with cathodal and sham stimulation. This effect was location specific. Bi-frontal cathodal stimulation did not significantly increase TST, potentially due to ceiling effects in good sleepers. Exploratory resting-state EEG analyses before and after the tDCS protocols were consistent with the notion of increased cortical arousal after anodal stimulation and decreased cortical arousal after cathodal stimulation. The study provides proof-of-concept that TST can be decreased by non-invasive bi-frontal anodal tDCS in healthy humans. Further elucidating the 'top-down' pathway of sleep-wake regulation is expected to increase knowledge on the fundamentals of sleep-wake regulation and to contribute to the development of novel treatments for clinical conditions of disturbed arousal and sleep.
Sleep restriction therapy for insomnia is associated with reduced objective total sleep time, increased daytime somnolence, and objectively impaired vigilance: implications for the clinical management of insomnia disorder.
Kyle, Simon D; Miller, Christopher B; Rogers, Zoe; Siriwardena, A Niroshan; Macmahon, Kenneth M; Espie, Colin A
To investigate whether sleep restriction therapy (SRT) is associated with reduced objective total sleep time (TST), increased daytime somnolence, and impaired vigilance. Within-subject, noncontrolled treatment investigation. Sleep research laboratory. Sixteen patients [10 female, mean age = 47.1 (10.8) y] with well-defined psychophysiological insomnia (PI), reporting TST ≤ 6 h. Patients were treated with single-component SRT over a 4-w protocol, sleeping in the laboratory for 2 nights prior to treatment initiation and for 3 nights (SRT night 1, 8, 22) during the acute interventional phase. The psychomotor vigilance task (PVT) was completed at seven defined time points [day 0 (baseline), day 1,7,8,21,22 (acute treatment) and day 84 (3 mo)]. The Epworth Sleepiness Scale (ESS) was completed at baseline, w 1-4, and 3 mo. Subjective sleep outcomes and global insomnia severity significantly improved before and after SRT. There was, however, a robust decrease in PSG-defined TST during acute implementation of SRT, by an average of 91 min on night 1, 78 min on night 8, and 69 min on night 22, relative to baseline (P insomnia.
Arnal, Pierrick J; Sauvet, Fabien; Leger, Damien; van Beers, Pascal; Bayon, Virginie; Bougard, Clément; Rabat, Arnaud; Millet, Guillaume Y; Chennaoui, Mounir
To investigate the effects of 6 nights of sleep extension on sustained attention and sleep pressure before and during total sleep deprivation and after a subsequent recovery sleep. Subjects participated in two experimental conditions (randomized cross-over design): extended sleep (EXT, 9.8 ± 0.1 h (mean ± SE) time in bed) and habitual sleep (HAB, 8.2 ± 0.1 h time in bed). In each condition, subjects performed two consecutive phases: (1) 6 nights of either EXT or HAB (2) three days in-laboratory: baseline, total sleep deprivation and after 10 h of recovery sleep. Residential sleep extension and sleep performance laboratory (continuous polysomnographic recording). 14 healthy men (age range: 26-37 years). EXT vs. HAB sleep durations prior to total sleep deprivation. Total sleep time and duration of all sleep stages during the 6 nights were significantly higher in EXT than HAB. EXT improved psychomotor vigilance task performance (PVT, both fewer lapses and faster speed) and reduced sleep pressure as evidenced by longer multiple sleep latencies (MSLT) at baseline compared to HAB. EXT limited PVT lapses and the number of involuntary microsleeps during total sleep deprivation. Differences in PVT lapses and speed and MSLT at baseline were maintained after one night of recovery sleep. Six nights of extended sleep improve sustained attention and reduce sleep pressure. Sleep extension also protects against psychomotor vigilance task lapses and microsleep degradation during total sleep deprivation. These beneficial effects persist after one night of recovery sleep. © 2015 Associated Professional Sleep Societies, LLC.
Honn, K A; Grant, D A; Hinson, J M; Whitney, P; Van Dongen, Hpa
Sleep deprivation impairs performance on cognitive tasks, but it is unclear which cognitive processes it degrades. We administered a semantic matching task with variable stimulus onset asynchrony (SOA) and both speeded and self-paced trial blocks. The task was administered at the baseline and 24 hours later after 30.8 hours of total sleep deprivation (TSD) or matching well-rested control. After sleep deprivation, the 20% slowest response times (RTs) were significantly increased. However, the semantic encoding time component of the RTs remained at baseline level. Thus, the performance impairment induced by sleep deprivation on this task occurred in cognitive processes downstream of semantic encoding.
Salo, Paula; Ala-Mursula, Leena; Rod, Naja Hulvej
OBJECTIVES: Employee control over work times has been associated with favorable psychosocial and health-related outcomes, but the evidence regarding sleep quality remains inconclusive. We examined cross-sectional and prospective associations between work time control and sleep disturbances...... in a large working population, taking into account total hours worked. METHODS: The data were from a full-panel longitudinal cohort study of Finnish public sector employees who responded to questions on work time control and sleep disturbances in years 2000-2001, 2004-2005, 2008-2009, and 2012. The analysis....... RESULTS: Consistently in both cross-sectional and longitudinal models, less control over work time was associated with greater sleep disturbances in the total population and among those working normal 40-hour weeks. Among participants working more than 40 hours a week, work time that was both very high...
Chua, Eric Chern-Pin; Shui, Guanghou; Cazenave-Gassiot, Amaury; Wenk, Markus R; Gooley, Joshua J
The effects of sleep loss on plasma lipids, which play an important role in energy homeostasis and signaling, have not been systematically examined. Our aim was to identify lipid species in plasma that increase or decrease reliably during exposure to total sleep deprivation. Twenty individuals underwent sleep deprivation in a laboratory setting. Blood was drawn every 4 h and mass spectrometry techniques were used to analyze concentrations of 263 lipid species in plasma, including glycerolipids, glycerophospholipids, sphingolipids, and sterols. Chronobiology and Sleep Laboratory, Duke-NUS Graduate Medical School. Healthy ethnic-Chinese males aged 21-28 y (n = 20). Subjects were kept awake for 40 consecutive hours. Each metabolite time series was modeled as a sum of sinusoidal (circadian) and linear components, and we assessed whether the slope of the linear component differed from zero. More than a third of all individually analyzed lipid profiles exhibited a circadian rhythm and/or a linear change in concentration during sleep deprivation. Twenty-five lipid species showed a linear and predominantly unidirectional trend in concentration levels that was consistent across participants. Choline plasmalogen levels decreased, whereas several phosphatidylcholine (PC) species and triacylglycerides (TAG) carrying polyunsaturated fatty acids increased. The decrease in choline plasmalogen levels during sleep deprivation is consistent with prior work demonstrating that these lipids are susceptible to degradation by oxidative stress. The increase in phosphatidylcholines and triacylglycerides suggests that sleep loss might modulate lipid metabolism, which has potential implications for metabolic health in individuals who do not achieve adequate sleep. © 2015 Associated Professional Sleep Societies, LLC.
Dispersyn, Garance; Sauvet, Fabien; Gomez-Merino, Danielle; Ciret, Sylvain; Drogou, Catherine; Leger, Damien; Gallopin, Thierry; Chennaoui, Mounir
Many studies on sleep deprivation effects lack data regarding the recovery period. We investigated the 2-day homeostatic and circadian sleep recovery response to 24 h of total sleep deprivation (TSD) induced by brief rotation of an activity wheel. Eight mice were implanted with telemetry transmitters (DSI F40-EET) that recorded simultaneously their electroencephalography (EEG), locomotor activity and temperature during 24 h of baseline (BSL), TSD and 2 days of recovery (D1 and D2). In a second experiment, two groups of five non-implanted mice underwent TSD or ad libitum sleep, after which they were killed, adrenal glands were weighed and blood was collected for analysis of corticosterone concentration. During TSD mice were awake at least 97% of the time, with a consecutive sleep rebound during D1 that persisted during D2. This was characterized by increases of non-rapid eye movement (NREM) sleep (44.2 ± 6.9% for D1 and 43.0 ± 7.7% for D2 versus 33.8 ± 9.2% for BSL) and the relative delta band power (179.2 ± 34.4% for D1 and 81.9 ± 11.2% for D2). Greater NREM and REM sleep amounts were observed during the 'light' periods. Temperature and locomotor activity characteristics were unchanged during D1 and D2 versus BSL. In non-implanted mice, corticosterone levels as well as adrenal gland and overall body weights did not differ between TSD and ad libitum sleep groups. In conclusion, 24 h of TSD in an activity wheel without stress responses influence homeostatic sleep regulation with no effect on the circadian regulation over at least 2 days of recovery in mice. © 2017 European Sleep Research Society.
... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Sleep time. 551.432 Section 551.432... FAIR LABOR STANDARDS ACT Hours of Work Special Situations § 551.432 Sleep time. (a) Except as provided in paragraph (b) of this section, bona fide sleep time that fulfills the following conditions shall...
... 29 Labor 3 2010-07-01 2010-07-01 false Sleep time. 553.222 Section 553.222 Labor Regulations... Enforcement Employees of Public Agencies Tour of Duty and Compensable Hours of Work Rules § 553.222 Sleep time... enforcement personnel in accordance with section 7(a)(1) of the Act, the public agency may exclude sleep time...
Esposito, Maria José; Occhionero, Miranda; Cicogna, PierCarla
To evaluate the effect of sleep deprivation on time-based prospective memory performance, that is, realizing delayed intentions at an appropriate time in the future (e.g., to take a medicine in 30 minutes). Between-subjects experimental design. The experimental group underwent 24 h of total sleep deprivation, and the control group had a regular sleep-wake cycle. Participants were tested at 08:00. Laboratory. Fifty healthy young adults (mean age 22 ± 2.1, 31 female). 24 h of total sleep deprivation. Participants were monitored by wrist actigraphy for 3 days before the experimental session. The following cognitive tasks were administered: one time-based prospective memory task and 3 reasoning tasks as ongoing activity. Objective and subjective vigilance was assessed by the psychomotor vigilance task and a visual analog scale, respectively. To measure the time-based prospective memory task we assessed compliance and clock checking behavior (time monitoring). Sleep deprivation negatively affected time-based prospective memory compliance (P sleep deprivation on human behavior, particularly the ability to perform an intended action after a few minutes. Sleep deprivation strongly compromises time-based prospective memory compliance but does not affect time check frequency. Sleep deprivation may impair the mechanism that allows the integration of information related to time monitoring with the prospective intention. © 2015 Associated Professional Sleep Societies, LLC.
Van Dongen, Hans P A.; Maislin, Greg; Mullington, Janet M.; Dinges, David F.
OBJECTIVES: To inform the debate over whether human sleep can be chronically reduced without consequences, we conducted a dose-response chronic sleep restriction experiment in which waking neurobehavioral and sleep physiological functions were monitored and compared to those for total sleep deprivation. DESIGN: The chronic sleep restriction experiment involved randomization to one of three sleep doses (4 h, 6 h, or 8 h time in bed per night), which were maintained for 14 consecutive days. The total sleep deprivation experiment involved 3 nights without sleep (0 h time in bed). Each study also involved 3 baseline (pre-deprivation) days and 3 recovery days. SETTING: Both experiments were conducted under standardized laboratory conditions with continuous behavioral, physiological and medical monitoring. PARTICIPANTS: A total of n = 48 healthy adults (ages 21-38) participated in the experiments. INTERVENTIONS: Noctumal sleep periods were restricted to 8 h, 6 h or 4 h per day for 14 days, or to 0 h for 3 days. All other sleep was prohibited. RESULTS: Chronic restriction of sleep periods to 4 h or 6 h per night over 14 consecutive days resulted in significant cumulative, dose-dependent deficits in cognitive performance on all tasks. Subjective sleepiness ratings showed an acute response to sleep restriction but only small further increases on subsequent days, and did not significantly differentiate the 6 h and 4 h conditions. Polysomnographic variables and delta power in the non-REM sleep EEG-a putative marker of sleep homeostasis--displayed an acute response to sleep restriction with negligible further changes across the 14 restricted nights. Comparison of chronic sleep restriction to total sleep deprivation showed that the latter resulted in disproportionately large waking neurobehavioral and sleep delta power responses relative to how much sleep was lost. A statistical model revealed that, regardless of the mode of sleep deprivation, lapses in behavioral alertness
Moore, Melisa; Kirchner, H Lester; Drotar, Dennis; Johnson, Nathan; Rosen, Carol; Redline, Susan
Adolescents are predisposed to short sleep duration and irregular sleep patterns due to certain host characteristics (e.g., age, pubertal status, gender, ethnicity, socioeconomic class, and neighborhood distress) and health-related variables (e.g., ADHD, asthma, birth weight, and BMI). The aim of the current study was to investigate the relationship between such variables and actigraphic measures of sleep duration and variability. Cross-sectional study of 247 adolescents (48.5% female, 54.3% ethnic minority, mean age of 13.7years) involved in a larger community-based cohort study. Significant univariate predictors of sleep duration included gender, minority ethnicity, neighborhood distress, parent income, and BMI. In multivariate models, gender, minority status, and BMI were significantly associated with sleep duration (all pminority adolescents, and those of a lower BMI obtaining more sleep. Univariate models demonstrated that age, minority ethnicity, neighborhood distress, parent education, parent income, pubertal status, and BMI were significantly related to variability in total sleep time. In the multivariate model, age, minority status, and BMI were significantly related to variability in total sleep time (all pminority adolescents, and those of a lower BMI obtaining more regular sleep. These data show differences in sleep patterns in population sub-groups of adolescents which may be important in understanding pediatric health risk profiles. Sub-groups that may particularly benefit from interventions aimed at improving sleep patterns include boys, overweight, and minority adolescents. Copyright © 2011 Elsevier B.V. All rights reserved.
Efficacy of treatment of insomnia in migraineurs with eszopiclone (Lunesta®) and its effect on total sleep time, headache frequency, and daytime functioning: A randomized, double-blind, placebo-controlled, parallel-group, pilot study.
Spierings, Egilius L H; McAllister, Peter J; Bilchik, Tanya R
A review on headache and insomnia revealed that insomnia is a risk factor for increased headache frequency and headache intensity in migraineurs. The authors designed a randomized, double blind, placebo-controlled, parallel-group, pilot study in which migraineurs who also had insomnia were enrolled, to test this observation. In the study, the authors treated 79 subjects with IHS-II migraine with and/or without aura and with DSM-IV primary insomnia for 6 weeks with 3 mg eszopiclone (Lunesta(®)) or placebo at bedtime. The treatment was preceded by a 2-week baseline period and followed by a 2-week run-out period. Of the 79 subjects treated, 75 were evaluable, 35 in the eszopiclone group, and 40 in the placebo group. At baseline, the groups were comparable except for sleep latency. Of the three remaining sleep variables, total sleep time, nighttime awakenings, and sleep quality, the number of nighttime awakenings during the 6-week treatment period was significantly lower in the eszopiclone group than in the placebo group (P = 0.03). Of the three daytime variables, alertness, fatigue, and functioning, this was also the case for fatigue (P = 005). The headache variables, frequency, duration, and intensity, did not show a difference from placebo during the 6-week treatment period. The study did not meet primary endpoint, that is, the difference in total sleep time during the 6-week treatment period between eszopiclone and placebo was less than 40 minutes. Therefore, it failed to answer the question as to whether insomnia is, indeed, a risk factor for increased headache frequency and headache intensity in migraineurs.
Manning, Blaine T; Kearns, Sean M; Bohl, Daniel D; Edmiston, Tori; Sporer, Scott M; Levine, Brett R
Sleep disruption is a common, yet rarely addressed, complaint among patients who have undergone total joint arthroplasty (TJA). This study assessed sleep quality before and after primary TJA. A total of 105 patients who underwent primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) prospectively completed questionnaires during the preoperative, early postoperative, and late postoperative periods. The survey included the Epworth Sleepiness Scale, current sleeping habits, and patient perspectives of sleep quality and duration. In the early postoperative period (4.7±2.0 weeks), patients reported significant increases in sleep disturbance as denoted by increased length of time to fall asleep (P=.006) and mean nightly awakenings (P=.002) compared with the preoperative baseline. At late postoperative follow-up (40.8±19.5 weeks), patients' sleep quality subsequently improved above the preoperative baseline. Approximately 40% of patients tried a new sleeping method postoperatively, the most common being new pillow placement. No significant differences in pre- or postoperative sleeping trends were noted between THA and TKA patients. These findings suggest transient sleep disturbance is common in the early postoperative period, with subsequent improvement by 10-month follow-up after a primary TJA. Given the growing importance of patient satisfaction in health care systems, orthopedic surgeons must manage patients' expectations while working with them to optimize sleep quality after TJA. A multimodal approach with preoperative counseling, early postoperative sleep modifications, and possibly preemptive use of medications may improve transient sleep disturbance among TJA patients. [Orthopedics. 2017; 40(4):e636-e640.]. Copyright 2017, SLACK Incorporated.
David L. Dickinson
Full Text Available Subjects performed a decision task (Grether, 1980 in both a well-rested and experimentally sleep-deprived state. We found two main results: 1 final choice accuracy was unaffected by sleep deprivation, and yet 2 the estimated decision model differed significantly following sleep-deprivation. Following sleep deprivation, subjects placed significantly less weight on new information in forming their beliefs. Because the altered decision process still maintains decision accuracy, it may suggest that increased accident and error rates attributed to reduced sleep in modern society stem from reduced auxiliary function performance (e.g., slowed reaction time, reduced motor skills or other components of decision making, rather than the inability to integrate multiple pieces of information.
Giskeødegård, Guro F; Davies, Sarah K; Revell, Victoria L; Keun, Hector; Skene, Debra J
Understanding how metabolite levels change over the 24 hour day is of crucial importance for clinical and epidemiological studies. Additionally, the association between sleep deprivation and metabolic disorders such as diabetes and obesity requires investigation into the links between sleep and metabolism. Here, we characterise time-of-day variation and the effects of sleep deprivation on urinary metabolite profiles. Healthy male participants (n = 15) completed an in-laboratory study comprising one 24 h sleep/wake cycle prior to 24 h of continual wakefulness under highly controlled environmental conditions. Urine samples were collected over set 2-8 h intervals and analysed by (1)H NMR spectroscopy. Significant changes were observed with respect to both time of day and sleep deprivation. Of 32 identified metabolites, 7 (22%) exhibited cosine rhythmicity over at least one 24 h period; 5 exhibiting a cosine rhythm on both days. Eight metabolites significantly increased during sleep deprivation compared with sleep (taurine, formate, citrate, 3-indoxyl sulfate, carnitine, 3-hydroxyisobutyrate, TMAO and acetate) and 8 significantly decreased (dimethylamine, 4-DTA, creatinine, ascorbate, 2-hydroxyisobutyrate, allantoin, 4-DEA, 4-hydroxyphenylacetate). These data indicate that sampling time, the presence or absence of sleep and the response to sleep deprivation are highly relevant when identifying biomarkers in urinary metabolic profiling studies.
Sleep duration has figured into claims of two trends promoted recently as dysfunctional in the mass media. One is the observation that the population at large is sleeping less than before. The second is that the annual change from Standard Time to Daylight Savings (or summer) Time causes adverse effects, largely through the loss of an hour's…
de Almeida Valverde Zanini, Gislaine; Tufik, Sérgio; Andersen, Monica Levy; da Silva, Raquel Cristina Martins; Bueno, Orlando Francisco Amodeo; Rodrigues, Camila Cruz; Pompéia, Sabine
One task that has been used to assess memory effects of prior total sleep deprivation (TSD) is the immediate free recall of word lists; however, results have been mixed. A possible explanation for this is task impurity, since recall of words from different serial positions reflects use of distinct types of memory (last words: short-term memory; first and intermediate words: episodic memory). Here we studied the effects of 2 nights of TSD on immediate free recall of semantically unrelated word lists considering the serial position curve. Random allocation to a 2-night TSD protocol followed by one night of recovery sleep or to a control group. Study conducted under continuous behavioral monitoring. 24 young, healthy male volunteers. 2 nights of total sleep deprivation (TSD) and one night of recovery sleep. Participants were shown five 15 unrelated word-lists at baseline, after one and 2 nights of TSD, and after one night of recovery sleep. We also investigated the development of recall strategies (learning) and susceptibility to interference from previous lists. No free recall impairment occurred during TSD, irrespective of serial position. Interference was unchanged. Both groups developed recall strategies, but task learning occurred earlier in controls and was evident in the TSD group only after sleep recovery. Prior TSD spared episodic memory, short-term phonological memory, and interference, allowed the development of recall strategies, but may have decreased the advantage of using these strategies, which returned to normal after recovery sleep.
Chua, Eric Chern-Pin; Fang, Eric; Gooley, Joshua J
Dividing attention across two tasks performed simultaneously usually results in impaired performance on one or both tasks. Most studies have found no difference in the dual-task cost of dividing attention in rested and sleep-deprived states. We hypothesized that, for a divided attention task that is highly cognitively-demanding, performance would show greater impairment during exposure to sleep deprivation. A group of 30 healthy males aged 21-30 years was exposed to 40 h of continuous wakefulness in a laboratory setting. Every 2 h, subjects completed a divided attention task comprising 3 blocks in which an auditory Go/No-Go task was 1) performed alone (single task); 2) performed simultaneously with a visual Go/No-Go task (dual task); and 3) performed simultaneously with both a visual Go/No-Go task and a visually-guided motor tracking task (triple task). Performance on all tasks showed substantial deterioration during exposure to sleep deprivation. A significant interaction was observed between task load and time since wake on auditory Go/No-Go task performance, with greater impairment in response times and accuracy during extended wakefulness. Our results suggest that the ability to divide attention between multiple tasks is impaired during exposure to sleep deprivation. These findings have potential implications for occupations that require multi-tasking combined with long work hours and exposure to sleep loss.
Eric Chern-Pin Chua
Full Text Available Dividing attention across two tasks performed simultaneously usually results in impaired performance on one or both tasks. Most studies have found no difference in the dual-task cost of dividing attention in rested and sleep-deprived states. We hypothesized that, for a divided attention task that is highly cognitively-demanding, performance would show greater impairment during exposure to sleep deprivation. A group of 30 healthy males aged 21-30 years was exposed to 40 h of continuous wakefulness in a laboratory setting. Every 2 h, subjects completed a divided attention task comprising 3 blocks in which an auditory Go/No-Go task was 1 performed alone (single task; 2 performed simultaneously with a visual Go/No-Go task (dual task; and 3 performed simultaneously with both a visual Go/No-Go task and a visually-guided motor tracking task (triple task. Performance on all tasks showed substantial deterioration during exposure to sleep deprivation. A significant interaction was observed between task load and time since wake on auditory Go/No-Go task performance, with greater impairment in response times and accuracy during extended wakefulness. Our results suggest that the ability to divide attention between multiple tasks is impaired during exposure to sleep deprivation. These findings have potential implications for occupations that require multi-tasking combined with long work hours and exposure to sleep loss.
Lasisi, Dr T J; Shittu, S T; Meludu, C C; Salami, A A
Aim of this study was to investigate the effects of sleep deprivation on salivary factors in rats. Animals were randomly assigned into three groups of 6 animals each as control, total sleep deprivation (TSD) and partial sleep deprivation (PSD) groups. The multiple platform method was used to induce partial and total sleep deprivation for 7days. On the 8th day, stimulated saliva samples were collected for the analysis of salivary lag time, flow rate, salivary amylase activity, immunoglobulin A secretion rate and corticosterone levels using ELISA and standard kinetic enzyme assay. Data were analyzed using ANOVA with Dunnett T3 post hoc tests. Salivary flow rate reduced significantly in the TSD group compared with the PSD group as well as the control group (p=0.01). The secretion rate of salivary IgA was significantly reduced in the TSD group compared with the control group (p=0.04). Salivary amylase activity was significantly elevated in the TSD group compared with the PSD group as well as control group (psalivary lag time and levels of corticosterone among the groups. These findings suggest that total sleep deprivation is associated with reduced salivary flow rate and secretion rate of IgA as well as elevated levels of salivary amylase activity in rats. However, sleep recovery of four hours in the PSD group produced ameliorative effects on the impaired functions of salivary glands. Copyright Â© 2016 Elsevier Ltd. All rights reserved.
Long, X.; Arends, J.B.A.M.; Aarts, R.M.; Haakma, R.; Fonseca, P.; Rolink, J.
Human sleep consists of wake, rapid-eye-movement (REM) sleep, and non-REM (NREM) sleep that includes light and deep sleep stages. This work investigated the time delay between changes of cardiac and brain activity for sleep transitions. Here, the brain activity was quantified by
Meltzer, Lisa J.; Shaheed, Keisha; Ambler, Devon
Homeschool students provide a naturalistic comparison group for later/flexible school start times. This study compared sleep patterns and sleep hygiene for homeschool students and public/private school students (grades 6-12). Public/private school students (n=245) and homeschool students (n=162) completed a survey about sleep patterns and sleep hygiene. Significant school group differences were found for weekday bedtime, wake time, and total sleep time, with homeschool students waking later and obtaining more sleep. Homeschool students had later school start times, waking at the same time that public/private school students were starting school. Public/private school students had poorer sleep hygiene practices, reporting more homework and use of technology in the hour before bed. Regardless of school type, technology in the bedroom was associated with shorter sleep duration. Later school start times may be a potential countermeasure for insufficient sleep in adolescents. Future studies should further examine the relationship between school start times and daytime outcomes, including academic performance, mood, and health. PMID:25315902
Dorsey, Cynthia M; Lukas, Scott E; Moore, Constance M; Tartarini, Wendy L; Parow, Aimee M; Villafuerte, Rosemond A; Renshaw, Perry F
To investigate chemical changes in the brains of healthy adults after sleep deprivation and recovery sleep, using phosphorous magnetic resonance spectroscopy. Three consecutive nights (baseline, sleep deprivation, recovery) were spent in the laboratory. Objective sleep measures were assessed on the baseline and recovery nights using polysomnography. Phosphorous magnetic resonance spectroscopy scans took place beginning at 7 am to 8 am on the morning after each of the 3 nights. Sleep laboratory in a private psychiatric teaching hospital. Eleven healthy young men. Following a baseline night of sleep, subjects underwent a night of total sleep deprivation, which involved supervision to ensure the absence of sleep but was not polysomnographically monitored. No significant changes in any measure of brain chemistry were observed the morning after a night of total sleep deprivation. However, after the recovery night, significant increases in total and beta-nucleoside triphosphate and decreases in phospholipid catabolism, measured by an increase in the concentration of glycerylphosphorylcholine, were observed. Chemical changes paralleled some changes in objective sleep measures. Significant chemical changes in the brain were observed following recovery sleep after 1 night of total sleep deprivation. The specific process underlying these changes is unclear due to the large brain region sampled in this exploratory study, but changes may reflect sleep inertia or some aspect of the homeostatic sleep mechanism that underlies the depletion and restoration of sleep. Phosphorous magnetic resonance spectroscopy is a technique that may be of value in further exploration of such sleep-wake functions.
Speth, Jana; Schloerscheidt, Astrid M; Speth, Clemens
We present a quantitative study of mental time travel to the future in sleep. Three independent, blind judges analysed a total of 563 physiology-monitored mentation reports from sleep onset, REM sleep, non-REM sleep, and waking. The linguistic tool for the mentation report analysis is based on established grammatical and cognitive-semantic theories and has been validated in previous studies. Our data indicate that REM and non-REM sleep must be characterized by a reduction in mental time travel to the future, which would support earlier physiological evidence at the level of brain function. Copyright © 2016 Elsevier Inc. All rights reserved.
Easton, Amy; Meerlo, Peter; Bergmann, Bernard; Turek, Fred W.
Context: Sleep is regulated by circadian and homeostatic processes. The circadian pacemaker, located in the suprachiasmatic nuclei (SCN), regulates the timing and consolidation of the sleep-wake cycle, while a homeostatic mechanism governs the accumulation of sleep debt and sleep, recovery. Recent
Wahlstrom, Kyla L.
Sleep studies have shown that teenagers' internal clocks are incompatible with most high schools' early hours. Research in two Minnesota districts indicates that later school starting times can benefit teens and everyone dealing with them. Student participation in sports and other afterschool activities remained high. (MLH)
Tucker, Philip; Albrecht, Sophie; Kecklund, Göran; Beckers, Debby G J; Leineweber, Constanze
We examined whether the beneficial impact of work time control (WTC) on sleep leads to lower accident risk, using data from a nationally representative survey conducted in Sweden. Logistic regressions examined WTC in 2010 and 2012 as predictors of accidents occurring in the subsequent 2 years (N = 4840 and 4337, respectively). Sleep disturbance and frequency of short sleeps in 2012 were examined as potential mediators of the associations between WTC in 2010 and subsequent accidents as reported in 2014 (N = 3636). All analyses adjusted for age, sex, education, occupational category, weekly work hours, shift work status, job control and perceived accident risk at work. In both waves, overall WTC was inversely associated with accidents (p = 0.048 and p = 0.038, respectively). Analyses of the sub-dimensions of WTC indicated that Control over Daily Hours (influence over start and finish times, and over length of shift) did not predict accidents in either wave, while Control over Time-off (CoT; influence over taking breaks, running private errands during work and taking paid leave) predicted fewer accidents in both waves (p = 0.013 and p = 0.010). Sleep disturbance in 2012 mediated associations between WTC/CoT in 2010 and accidents in 2014, although effects' sizes were small (effectWTC = -0.006, 95% confidence interval [CI] = -0.018 to -0.001; effectCoT = -0.009, 95%CI = -0.022 to -0.001; unstandardized coefficients), with the indirect effects of sleep disturbance accounting for less than 5% of the total direct and indirect effects. Frequency of short sleeps was not a significant mediator. WTC reduces the risk of subsequently being involved in an accident, although sleep may not be a strong component of the mechanism underlying this association.
Liu, Jean C J; Verhulst, Silvan; Massar, Stijn A A; Chee, Michael W L
We examined how sleep deprivation alters physiological responses to psychosocial stress by evaluating changes in skin conductance. Between-subjects design with one group allocated to 24 h of total sleep deprivation and the other to rested wakefulness. The study took place in a research laboratory. Participants were 40 healthy young adults recruited from a university. Sleep deprivation and feedback. Electrodermal activity was monitored while participants completed a difficult perceptual task with false feedback. All participants showed increased skin conductance levels following stress. However, compared to well-rested participants, sleep deprived participants showed higher skin conductance reactivity with increasing stress levels. Our results suggest that sleep deprivation augments allostatic responses to increasing psychosocial stress. Consequentially, we propose sleep loss as a risk factor that can influence the pathogenic effects of stress. © 2014 Associated Professional Sleep Societies, LLC.
Ramakrishnan, Sridhar; Lu, Wei; Laxminarayan, Srinivas; Wesensten, Nancy J; Rupp, Tracy L; Balkin, Thomas J; Reifman, Jaques
Humans display a trait-like response to sleep loss. However, it is not known whether this trait-like response can be captured by a mathematical model from only one sleep-loss condition to facilitate neurobehavioural performance prediction of the same individual during a different sleep-loss condition. In this paper, we investigated the extent to which the recently developed unified mathematical model of performance (UMP) captured such trait-like features for different sleep-loss conditions. We used the UMP to develop two sets of individual-specific models for 15 healthy adults who underwent two different sleep-loss challenges (order counterbalanced; separated by 2-4 weeks): (i) 64 h of total sleep deprivation (TSD) and (ii) chronic sleep restriction (CSR) of 7 days of 3 h nightly time in bed. We then quantified the extent to which models developed using psychomotor vigilance task data under TSD predicted performance data under CSR, and vice versa. The results showed that the models customized to an individual under one sleep-loss condition accurately predicted performance of the same individual under the other condition, yielding, on average, up to 50% improvement over non-individualized, group-average model predictions. This finding supports the notion that the UMP captures an individual's trait-like response to different sleep-loss conditions. © 2014 European Sleep Research Society.
Beyens, Ine; Nathanson, Amy I
This study examined the association between electronic media use and sleep among preschoolers, using a national sample of 402 mothers of 3- to 5-year-olds. Participants completed an online survey assessing preschoolers' electronic media use, bedtime and wake time, sleep time, napping behaviors, and sleep consolidation. Results showed that heavier television use and tablet use, both overall and in the evening, were associated with later bedtimes and later wake times, but not with fewer hours of sleep, providing evidence for a time-shifting process. In addition, heavier daily television use and evening smartphone use were associated with increased daytime napping. Moreover, heavier daily television use, daily and evening smartphone use, and evening tablet use were associated with poorer sleep consolidation, suggesting less mature sleep patterns. These findings indicate that media effects on the timing of sleep and the proportion of sleep that occurs at night are important to consider when assessing the health risks of electronic media on children.
Laura E. Dennis
Full Text Available Experimental studies have shown that sleep restriction (SR and total sleep deprivation (TSD produce increased caloric intake, greater fat consumption, and increased late-night eating. However, whether individuals show similar energy intake responses to both SR and TSD remains unknown. A total of N = 66 healthy adults (aged 21–50 years, 48.5% women, 72.7% African American participated in a within-subjects laboratory protocol to compare daily and late-night intake between one night of SR (4 h time in bed, 04:00–08:00 and one night of TSD (0 h time in bed conditions. We also examined intake responses during subsequent recovery from SR or TSD and investigated gender differences. Caloric and macronutrient intake during the day following SR and TSD were moderately to substantially consistent within individuals (Intraclass Correlation Coefficients: 0.34–0.75. During the late-night period of SR (22:00–04:00 and TSD (22:00–06:00, such consistency was slight to moderate, and participants consumed a greater percentage of calories from protein (p = 0.01 and saturated fat (p = 0.02 during SR, despite comparable caloric intake (p = 0.12. Similarly, participants consumed a greater percentage of calories from saturated fat during the day following SR than TSD (p = 0.03. Participants also consumed a greater percentage of calories from protein during recovery after TSD (p < 0.001. Caloric intake was greater in men during late-night hours and the day following sleep loss. This is the first evidence of phenotypic trait-like stability and differential vulnerability of energy balance responses to two commonly experienced types of sleep loss: our findings open the door for biomarker discovery and countermeasure development to predict and mitigate this critical health-related vulnerability.
Dennis, Laura E; Spaeth, Andrea M; Goel, Namni
Experimental studies have shown that sleep restriction (SR) and total sleep deprivation (TSD) produce increased caloric intake, greater fat consumption, and increased late-night eating. However, whether individuals show similar energy intake responses to both SR and TSD remains unknown. A total of N = 66 healthy adults (aged 21-50 years, 48.5% women, 72.7% African American) participated in a within-subjects laboratory protocol to compare daily and late-night intake between one night of SR (4 h time in bed, 04:00-08:00) and one night of TSD (0 h time in bed) conditions. We also examined intake responses during subsequent recovery from SR or TSD and investigated gender differences. Caloric and macronutrient intake during the day following SR and TSD were moderately to substantially consistent within individuals (Intraclass Correlation Coefficients: 0.34-0.75). During the late-night period of SR (22:00-04:00) and TSD (22:00-06:00), such consistency was slight to moderate, and participants consumed a greater percentage of calories from protein ( p = 0.01) and saturated fat ( p = 0.02) during SR, despite comparable caloric intake ( p = 0.12). Similarly, participants consumed a greater percentage of calories from saturated fat during the day following SR than TSD ( p = 0.03). Participants also consumed a greater percentage of calories from protein during recovery after TSD ( p sleep loss. This is the first evidence of phenotypic trait-like stability and differential vulnerability of energy balance responses to two commonly experienced types of sleep loss: our findings open the door for biomarker discovery and countermeasure development to predict and mitigate this critical health-related vulnerability.
Dewald, Julia F; Meijer, Anne Marie; Oort, Frans J; Kerkhof, Gerard A; Bögels, Susan M
This prospective quasi-experiment (N = 175; mean age = 15.14 years) investigates changes in adolescents' sleep from low-stress (regular school week) to high-stress times (exam week), and examines the (moderating) role of chronic sleep reduction, baseline stress, and gender. Sleep was monitored over three consecutive weeks using actigraphy. Adolescents' sleep was more fragmented during the high-stress time than during the low-stress time, meaning that individuals slept more restless during stressful times. However, sleep efficiency, total sleep time, and sleep onset latency remained stable throughout the three consecutive weeks. High chronic sleep reduction was related to later bedtimes, later sleep start times, later sleep end times, later getting up times, and more time spent in bed. Furthermore, low chronic sleep reduction and high baseline stress levels were related to more fragmented sleep during stressful times. This study shows that stressful times can have negative effects on adolescents' sleep fragmentation, especially for adolescents with low chronic sleep reduction or high baseline stress levels.
Miller, Nita Lewis; Tvaryanas, Anthony P; Shattuck, Lawrence G
This study evaluated the effect of accommodating adolescent sleep-wake patterns by altering the timing of the major sleep period of US Army recruits. The quasi-experimental study compared recruits assigned to one of two training companies: one with a customary sleep regimen (20:30 to 04:30) while the other employed a phase-delayed sleep regimen (23:00 to 07:00), the latter aligning better with biologically driven sleep-wake patterns of adolescents. The study was conducted during Basic Combat Training (BCT) at Fort Leonard Wood, Missouri. TRAINEES: The study included 392 trainees: 209 received the intervention, while 183 composed the Comparison group. Demographic and psychophysiological measures were collected on all trainees. Weekly assessments of subjective fatigue and mood, periodic physical fitness, marksmanship scores, and attrition rates from BCT were studied. Actigraphy was collected on approximately 24% of trainees. Based on actigraphy, trainees on the phase-delayed sleep schedule obtained 31 m more sleep/night than trainees on the customary sleep schedule. The Intervention group reported less total mood disturbance relative to baseline. Improvements in marksmanship correlated positively with average nightly sleep during the preceding week when basic marksmanship skills were taught. No differences were seen in physical fitness or attrition rates. In contrast to the Intervention group, the Comparison group was 2.3 times more likely to experience occupationally significant fatigue and 5.5 times more likely to report poor sleep quality. Accommodating adolescent sleep patterns significantly improves mental health and performance in the training environment.
Full Text Available Aim. The aim of this study was to identify the impact of bedtime, wake time, sleep duration, sleep-onset latency, and sleep quality on depressive symptoms and suicidal ideation amongst Japanese freshmen. Methods. This cross-sectional data was derived from the baseline survey of the Enhancement of Q-University Students Intelligence (EQUSITE study conducted from May to June, 2010. A total of 2,631 participants were recruited and completed the following self-reported questionnaires: the Pittsburgh Sleep Quality Index (PSQI, the Center for Epidemiologic Studies Depression Scale (CES-D, and the original Health Support Questionnaires developed by the EQUSITE study research team. Results. Of 1,992 participants eligible for analysis, 25.5% (n=507 reported depressive symptoms (CES-D total score ≥ 16, and 5.8% (n=115 reported suicidal ideation. The present study showed that late bedtime (later than 01:30, sleep-onset latency (≥30 minutes, and poor sleep quality showed a marginally significant association with depressive symptoms. Poor sleep quality was seen to predict suicidal ideation even after adjusting for depressive symptoms. Conclusion. The current study has important implications for the role of bedtime in the prevention of depressive symptoms. Improving sleep quality may prevent the development of depressive symptoms and reduce the likelihood of suicidal ideation.
Beersma, Domien G.M.; Daan, Serge; Hoofdakker, Rutger H. van den
Endogenously depressed subjects frequently show severe sleep problems. In this article sleep time in depression is discussed in relation to a recently developed model for sleep timing in healthy subjects. In terms of the model, two parameter sets survive a qualitative comparison with the empirical
Long, Xi; Arends, Johan B.; Aarts, Ronald M.; Haakma, Reinder; Fonseca, Pedro; Rolink, Jérôme
Human sleep consists of wake, rapid-eye-movement (REM) sleep, and non-REM (NREM) sleep that includes light and deep sleep stages. This work investigated the time delay between changes of cardiac and brain activity for sleep transitions. Here, the brain activity was quantified by electroencephalographic (EEG) mean frequency and the cardiac parameters included heart rate, standard deviation of heartbeat intervals, and their low- and high-frequency spectral powers. Using a cross-correlation analysis, we found that the cardiac variations during wake-sleep and NREM sleep transitions preceded the EEG changes by 1-3 min but this was not the case for REM sleep transitions. These important findings can be further used to predict the onset and ending of some sleep stages in an early manner.
Ma, Ning; Dinges, David F.; Basner, Mathias; Rao, Hengyi
Study Objectives: Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Design: Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. Methods: The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. Results: The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Conclusion: Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. Citation: Ma N, Dinges DF, Basner M, Rao H. How acute total
Drummond, Sean P
.... Even less is known about the cerebral effects of recovery sleep. The overarching objective of this study is to investigate the effects of 2 full nights of sleep loss and 2 full nights of recovery sleep on cognitive performance and brain function...
..... Even less is known about the cerebral effects of recovery sleep. The objective of this study is to investigate the effects of 2 full nights of sleep loss and 2 full nights of recovery sleep on cognitive performance and brain function...
Full Text Available Contextual cues are known to benefit memory retrieval, but whether and how sleep affects this context effect remains unresolved. We manipulated contextual congruence during memory retrieval in human volunteers across 12 h and 24 h intervals beginning with either sleep or wakefulness. Our data suggest that whereas contextual cues lose their potency with time, sleep does not modulate this process. Furthermore, our results are consistent with the idea that sleep's beneficial effect on memory retention depends on the amount of waking time that has passed between encoding and sleep onset. The findings are discussed in the framework of competitive consolidation theory.
Olbrich, Eckehard; Claussen, Jens Christian; Achermann, Peter
A particular property of the sleeping brain is that it exhibits dynamics on very different time scales ranging from the typical sleep oscillations such as sleep spindles and slow waves that can be observed in electroencephalogram (EEG) segments of several seconds duration over the transitions between the different sleep stages on a time scale of minutes to the dynamical processes involved in sleep regulation with typical time constants in the range of hours. There is an increasing body of work on mathematical and computational models addressing these different dynamics, however, usually considering only processes on a single time scale. In this paper, we review and present a new analysis of the dynamics of human sleep EEG at the different time scales and relate the findings to recent modelling efforts pointing out both the achievements and remaining challenges.
Cibella, F; Marrone, O; Sanci, S; Bellia, V; Bonsignore, G
Diaphragmatic electromyogram was recorded during NREM sleep in 4 patients affected by obstructive sleep apnoea (OSA) syndrome in order to evaluate the behaviour of expiratory time (TE) in the course of the obstructive apnoea-ventilation cycle. The two components of TE, i.e. time of post-inspiratory inspiratory activity (TPIIA) and time of expiratory phase 2 (TE2) were separately analysed. TPIIA showed a short duration, with only minor variations, within the apnoea, while its duration was more variable and longer in the interapnoeic periods: the longest TPIIA values were associated with the highest inspiratory volumes in the same breaths. This behaviour seemed regulated according to the need of a more or less effective expiratory flow braking, probably as a result of pulmonary stretch receptors discharge. Conversely TE2 showed a continuous gradual modulation, progressively increasing in the pre-apnoeic period, decreasing during the apnoea and increasing in the post-apnoeic period: these TE2 variations seemed related to oscillations in chemical drive. These data show that TE in the obstructive apnoea-ventilation cycle results from a different modulation in its two components and suggest that both mechanical and chemical influences play a role in its overall duration.
Whitney, Paul; Hinson, John M; Jackson, Melinda L; Van Dongen, Hans P A
To better understand the sometimes catastrophic effects of sleep loss on naturalistic decision making, we investigated effects of sleep deprivation on decision making in a reversal learning paradigm requiring acquisition and updating of information based on outcome feedback. Subjects were randomized to a sleep deprivation or control condition, with performance testing at baseline, after 2 nights of total sleep deprivation (or rested control), and following 2 nights of recovery sleep. Subjects performed a decision task involving initial learning of go and no go response sets followed by unannounced reversal of contingencies, requiring use of outcome feedback for decisions. A working memory scanning task and psychomotor vigilance test were also administered. Six consecutive days and nights in a controlled laboratory environment with continuous behavioral monitoring. Twenty-six subjects (22-40 y of age; 10 women). Thirteen subjects were randomized to a 62-h total sleep deprivation condition; the others were controls. Unlike controls, sleep deprived subjects had difficulty with initial learning of go and no go stimuli sets and had profound impairment adapting to reversal. Skin conductance responses to outcome feedback were diminished, indicating blunted affective reactions to feedback accompanying sleep deprivation. Working memory scanning performance was not significantly affected by sleep deprivation. And although sleep deprived subjects showed expected attentional lapses, these could not account for impairments in reversal learning decision making. Sleep deprivation is particularly problematic for decision making involving uncertainty and unexpected change. Blunted reactions to feedback while sleep deprived underlie failures to adapt to uncertainty and changing contingencies. Thus, an error may register, but with diminished effect because of reduced affective valence of the feedback or because the feedback is not cognitively bound with the choice. This has important
Christensen, Matthew A; Bettencourt, Laura; Kaye, Leanne; Moturu, Sai T; Nguyen, Kaylin T; Olgin, Jeffrey E; Pletcher, Mark J; Marcus, Gregory M
Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality. The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep. We performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years). Smartphone screen-time (the number of minutes in each hour the screen was on) was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index-PSQI) were obtained by survey. Linear regression was used to obtain effect estimates. Total screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3) and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5). Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency. These findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata suggesting that
Matthew A Christensen
Full Text Available Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality.The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep.We performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years. Smartphone screen-time (the number of minutes in each hour the screen was on was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index-PSQI were obtained by survey. Linear regression was used to obtain effect estimates.Total screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3 and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5. Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency.These findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata
Ma, Ning; Dinges, David F; Basner, Mathias; Rao, Hengyi
Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. © 2015 Associated Professional Sleep Societies, LLC.
Hurdiel, Rémy; Van Dongen, Hans P A; Aron, Christophe; McCauley, Peter; Jacolot, Laure; Theunynck, Denis
In solo offshore sailing races like those of the Solitaire du Figaro, sleep must be obtained in multiple short bouts to maintain competitive performance and safety. Little is known about the amount of sleep restriction experienced at sea and the effects that fatigue from sleep loss have on sailors' performance. Therefore, we assessed sleep in sailors of yachts in the Figaro 2 Beneteau class during races and compared response times on a serial simple reaction-time test before and after races. Twelve men (professional sailors) recorded their sleep and measured their response times during one of the three single-handed races of 150, 300 and 350 nautical miles (nominally 24-50 h in duration). Total estimated sleep duration at sea indicated considerable sleep insufficiency. Response times were slower after races than before. The results suggest that professional sailors incur severe sleep loss and demonstrate marked performance impairment when competing in one- to two-day solo sailing races. Competitive performance could be improved by actively managing sleep during solo offshore sailing races.
Quera-Salva, M A; McCann, C; Boudet, J; Frisk, M; Borderies, P; Meyer, P
1. In a double-blind, crossover, placebo controlled trial, zolpidem 10 mg, a new imidazopyridine hypnotic drug, was administered in a single dose to 10 healthy non-obese heavy snorers. 2. Nocturnal polysomnography showed that zolpidem increased total sleep time, sleep efficiency and the percentage of stage 2. 3. Respiratory monitoring showed that zolpidem did not modify the percentage of total sleep time spent snoring. The percentages of total sleep time with a SaO2 < 4% of the baseline value and with a SaO2 < 90% and the mean SaO2 were also unchanged with zolpidem. The respiratory disturbance index was modestly increased by zolpidem although in all but one subject it remained < 5 with both treatments. 4. Zolpidem intake did not impair daytime vigilance and performance evaluated the day after. PMID:7917771
Sack, R. L.; Blood, M. L.; Hughes, R. J.; Lewy, A. J.
Discusses the diagnosis and management of "non-24-hour sleep-wake syndrome," a form of cyclic insomnia to which people who are totally blind are prone. Covered are incidence and clinical features, formal diagnostic criteria, the biological basis of circadian sleep disorders, circadian rhythms in blind people, pharmacological entrainment,…
Temkin, Deborah A.; Princiotta, Daniel; Ryberg, Renee; Lewin, Daniel S.
Background: Although adolescents generally get less than the recommended 9 hours of sleep per night, research and effort to delay school start times have generally focused on high schools. This study assesses the relation between school start times and sleep in middle school students while accounting for potentially confounding demographic…
Verweij, Ilse M; Onuki, Yoshiyuki; Van Someren, Eus J W; Van der Werf, Ysbrand D
Growing evidence suggests that sleep is important for procedural learning, but few studies have investigated the effect of sleep on the temporal aspects of motor skill learning. We assessed the effect of a 90-min day-time nap on learning a motor timing task, using 2 adaptations of a serial
Drummond, Sean P
.... Although considerable data show that sleep deprivation alters many aspects of behavior, little is known about changes in the brain substrate underlying the behavioral effects, and even less is known...
Drummond, Sean P
.... Although considerable data show that sleep deprivation alters many aspects of behavior, little is known about changes in the brain substrate underlying the behavioral effects, and even less is known...
Whitney, Paul; Hinson, John M.; Jackson, Melinda L.; Van Dongen, Hans P.A.
Study Objectives: To better understand the sometimes catastrophic effects of sleep loss on naturalistic decision making, we investigated effects of sleep deprivation on decision making in a reversal learning paradigm requiring acquisition and updating of information based on outcome feedback. Design: Subjects were randomized to a sleep deprivation or control condition, with performance testing at baseline, after 2 nights of total sleep deprivation (or rested control), and following 2 nights of recovery sleep. Subjects performed a decision task involving initial learning of go and no go response sets followed by unannounced reversal of contingencies, requiring use of outcome feedback for decisions. A working memory scanning task and psychomotor vigilance test were also administered. Setting: Six consecutive days and nights in a controlled laboratory environment with continuous behavioral monitoring. Subjects: Twenty-six subjects (22–40 y of age; 10 women). Interventions: Thirteen subjects were randomized to a 62-h total sleep deprivation condition; the others were controls. Results: Unlike controls, sleep deprived subjects had difficulty with initial learning of go and no go stimuli sets and had profound impairment adapting to reversal. Skin conductance responses to outcome feedback were diminished, indicating blunted affective reactions to feedback accompanying sleep deprivation. Working memory scanning performance was not significantly affected by sleep deprivation. And although sleep deprived subjects showed expected attentional lapses, these could not account for impairments in reversal learning decision making. Conclusions: Sleep deprivation is particularly problematic for decision making involving uncertainty and unexpected change. Blunted reactions to feedback while sleep deprived underlie failures to adapt to uncertainty and changing contingencies. Thus, an error may register, but with diminished effect because of reduced affective valence of the feedback
Thacher, Pamela V.; Onyper, Serge V.
Study Objectives: To establish whether sleep, health, mood, behavior, and academics improved after a 45-minute delay in high school start time, and whether changes persisted longitudinally. Methods: We collected data from school records and student self-report across a number of domains at baseline (May 2012) and at two follow-up time points (November 2012 and May 2013), at a public high school in upstate New York. Students enrolled during academic years (AY) 2011–2012 and 2012–2013 completed the Pittsburgh Sleep Quality Index; the DASS-21; the “Owl-Lark” Scale; the Daytime Sleepiness Index; and a brief self-report of health. Reports from school records regarding attendance, tardiness, disciplinary violations, and academic performance were collected for AY 2010–2011 through 2013–2014. Results: Students delayed but did not extend their sleep period; we found lasting improvements in tardiness and disciplinary violations after the start-time delay, but no changes to other variables. At the first follow-up, students reported 20 minutes longer sleep, driven by later rise times and stable bed times. At the second follow-up, students maintained later rise times but delayed bedtimes, returning total sleep to baseline levels. A delay in rise time, paralleling the delay in the start time that occurred, resulted in less tardiness and decreased disciplinary incidents, but larger improvements to sleep patterns may be necessary to affect health, attendance, sleepiness, and academic performance. Conclusions: Later start times improved tardiness and disciplinary issues at this school district. A delay in start time may be a necessary but not sufficient means to increase sleep time and may depend on preexisting individual differences. Commentary: A commentary on this article appears in this issue on page 267. Citation: Thacher PV, Onyper SV. Longitudinal outcomes of start time delay on sleep, behavior, and achievement in high school. SLEEP 2016;39(2):271–281. PMID
Erren, Thomas C
With a focus on melatonin, a recent paper in the Journal investigated the hypothesis that endometrial cancer might be associated with the duration, and ultimately, amount of sleep. The authors found that "[s]elf-reported sleep duration may not adequately represent melatonin levels." The authors also concluded that there was "weak evidence of an association between sleep duration and endometrial cancer risk." Overall, these are interesting observations because primarily experimental and mechanistic research from many angles supports the study's notion that inappropriate sleep may be a determinant of cancer risk. To find out whether this is so in man, rather than assigning study individuals to fixed or average "baseline sleep categories" i.e., ≤5, 6, 7, 8, ≥9 h of habitual sleep in the present study, the accumulated amount of sleep over decades should be reconstructed in retrospective or constructed in prospective studies. To achieve this end, future epidemiological studies may want to use a sleep-years index [SYI]. This simple exposure parameter promises to be a sensible, feasible, and affordable way to approximate cumulative time spent at sleep in critical time windows over many years which we should expect to be relevant for the development of cancer. The SYI could be tested and used in observational studies which promise to be comparable and can be merged. This commentary provides roots of the index and explains why and how it should be used and how it could be interpreted in rigorous studies of biologically plausible links between sleep, on the one hand, and the development of internal cancers, on the other. This commentary also points out limitations of interpreting the SYI. It is emphasized that, where possible, the SYI should be assessed independently of (a) other sleep facets--such as quality--and of (b) known or suspected cancer risk factors. The respective contribution of (a) and (b) to risk must then be assessed during the analyses. Overall, the
Verweij, Ilse M; Onuki, Yoshiyuki; Van Someren, Eus J W; Van der Werf, Ysbrand D
Growing evidence suggests that sleep is important for procedural learning, but few studies have investigated the effect of sleep on the temporal aspects of motor skill learning. We assessed the effect of a 90-min day-time nap on learning a motor timing task, using 2 adaptations of a serial interception sequence learning (SISL) task. Forty-two right-handed participants performed the task before and after a 90-min period of sleep or wake. Electroencephalography (EEG) was recorded throughout. The motor task consisted of a sequential spatial pattern and was performed according to 2 different timing conditions, that is, either following a sequential or a random temporal pattern. The increase in accuracy was compared between groups using a mixed linear regression model. Within the sleep group, performance improvement was modeled based on sleep characteristics, including spindle- and slow-wave density. The sleep group, but not the wake group, showed improvement in the random temporal, but especially and significantly more strongly in the sequential temporal condition. None of the sleep characteristics predicted improvement on either general of the timing conditions. In conclusion, a daytime nap improves performance on a timing task. We show that performance on the task with a sequential timing sequence benefits more from sleep than motor timing. More important, the temporal sequence did not benefit initial learning, because differences arose only after an offline period and specifically when this period contained sleep. Sleep appears to aid in the extraction of regularities for optimal subsequent performance. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Kelly, Ryan J.; El-Sheikh, Mona
Child sleep and adjustment research with community samples is on the rise with a recognized need of explicating this association. We examined reciprocal relations between children's sleep and their internalizing and externalizing symptoms using 3 waves of data spanning 5 years. Participants included 176 children at Time 1 (M = 8.68 years; 69%…
Cha, Seung-Eun; Eun, Ki-Soo
Although the gender gap in sleep time has narrowed significantly in the last decade, middle-aged women between ages 35 and 60 still sleep less than their male counterparts in Korea. This study examines and provides evidence for factors contributing to the gender gap in this age group. Using Korean Time Use Survey (KTUS) data from 2004, 2009 and 2014, we find that middle-aged women’s difficulty in managing work-life balance and traditional role expectations placed upon women are the main causes of the gender gap in sleep time. The decomposition analysis reveals that the improved socioeconomic status and recent changes in familial expectations for women may have helped them sleep more than in the past. However, there remain fundamental differences in attitude and time use patterns between men and women that prevent middle-aged women from getting the same amount of sleep.
Orr, W C; Goodrich, S; Estep, M E; Shepherd, K
This study investigated whether the complaint of night-time heartburn (NHB) as opposed to daytime heartburn (DHB) is a reliable reflection of actual sleep-related reflux events. Three groups of individuals were studied: individuals with complaints of NHB at least twice per week (n = 24), individuals with complaints of DHB (n = 23), and normal participants without any complaints of regular heartburn during the day or night (n = 25). All three groups were studied on one occasion with combined pH monitoring and polysomnography, and subjective questionnaires about sleep disturbance and sleep quality were given to all participants. The NHB group had significantly more sleep-related reflux events compared with both DHB and control groups (P < 0.01). DHB subjects had significantly (P < 0.05) more sleep-related reflux events than normal controls. Total acid contact time (ACT) was significantly (P < 0.05) elevated in the NHB group compared with both the DHB and control group. Sleep-related ACT was also significantly (P < 0.05) elevated in the NHB group compared with the other two groups, while upright (daytime) ACT was not significantly different. The NHB group was significantly (P < 0.05) worse regarding measures of both objective and subjective sleep quality. Subjects with exclusively DHB do have sleep-related reflux that is greater than normal controls. Subjects with NHB have significantly more sleep-related reflux, and both objective and subjective sleep abnormalities compared with normal controls. Complaints of NHB reflect sleep-related reflux events and may be indicative of a more clinically significant condition. © 2013 Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.
Wahlstrom, Kyla L; Berger, Aaron T; Widome, Rachel
The objectives were 2-fold: (1) to examine how high school start times relate to adolescent sleep duration, and (2) to test associations between sleep duration and mental health- and substance use-related issues and behaviors in teens. This study examines selected questions from survey data collected between 2010 and 2013 high school students. Respondents included more than 9000 students in grades 9 to 12 in 8 high schools in 5 school districts across the United States. The survey instrument is the 97-item Teen Sleep Habits Survey. Logistic regression models were used to calculate adjusted odds ratios and 95% confidence intervals. Because of clustering within schools and the use of repeated measures, generalized estimating equations were used to account for variance inflation. Greater sleep duration was associated with fewer reports of various mental health- and substance use-related issues and behaviors (all P values sleep reported, there was a 28% reduction in the adjusted odds of a participant reporting that he or she felt "unhappy, sad, or depressed." Later wake-up times were associated with a reduction in risk for some, but not all factors. Later start times were significantly associated with greater sleep duration. Given that later start times allow for greater sleep duration and that adequate sleep duration is associated with more favorable mental health- and substance use-related issues and behaviors, it is important that school districts prioritize exploring and implementing policies, such as delayed start times, that may increase the amount of sleep of adolescent students, which is needed for their optimal development. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.
Tripathi, Shweta; Jha, Sushil K
Short-term sleep deprivation soon after training may impair memory consolidation. Also, a particular sleep stage or its components increase after learning some tasks, such as negative and positive reinforcement tasks, avoidance tasks, and spatial learning tasks, and so forth. It suggests that discrete memory types may require specific sleep stage or its components for their optimal processing. The classical conditioning paradigms are widely used to study learning and memory but the role of sleep in a complex conditioned learning is unclear. Here, we have investigated the effects of short-term sleep deprivation on the consolidation of delay-conditioned memory and the changes in sleep architecture after conditioning. Rats were trained for the delay-conditioned task (for conditioning, house-light [conditioned stimulus] was paired with fruit juice [unconditioned stimulus]). Animals were divided into 3 groups: (a) sleep deprived (SD); (b) nonsleep deprived (NSD); and (c) stress control (SC) groups. Two-way ANOVA revealed a significant interaction between groups and days (training and testing) during the conditioned stimulus-unconditioned stimulus presentation. Further, Tukey post hoc comparison revealed that the NSD and SC animals exhibited significant increase in performances during testing. The SD animals, however, performed significantly less during testing. Further, we observed that wakefulness and NREM sleep did not change after training and testing. Interestingly, REM sleep increased significantly on both days compared to baseline more specifically during the initial 4-hr time window after conditioning. Our results suggest that the consolidation of delay-conditioned memory is sleep-dependent and requires augmented REM sleep during an explicit time window soon after training. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Dexter, Donn; Bijwadia, Jagdeep; Schilling, Dana; Applebaugh, Gwendolyn
High school students are reported to be excessively sleepy, resulting in decreased academic performance, increased psycho-social problems and increased risk of morbidity and mortality from accidents. Early school start times have been noted to contribute to this problem. This report attempts to confirm the relationship of early school start times with decreased sleep and increased sleepiness. We examined sophomore and junior students in 2 local high schools with different start times and measured the amount of time slept and sleepiness. We found that students at the early start school reported reduced sleep time and more sleepiness than their counterparts at the later starting school. Early school start times are associated with student reports of less sleep and increased sleepiness. Further studies in larger groups are recommended in view of the potential significant impact of sleep deprivation in this age group.
Lee, Michael L; Katsuyama, Ângela M; Duge, Leanne S; Sriram, Chaitra; Krushelnytskyy, Mykhaylo; Kim, Jeansok J; de la Iglesia, Horacio O
Sleep is important for consolidation of hippocampus-dependent memories. It is hypothesized that the temporal sequence of nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep is critical for the weakening of nonadaptive memories and the subsequent transfer of memories temporarily stored in the hippocampus to more permanent memories in the neocortex. A great body of evidence supporting this hypothesis relies on behavioral, pharmacological, neural, and/or genetic manipulations that induce sleep deprivation or stage-specific sleep deprivation. We exploit an experimental model of circadian desynchrony in which intact animals are not deprived of any sleep stage but show fragmentation of REM and NREM sleep within nonfragmented sleep bouts. We test the hypothesis that the shortening of NREM and REM sleep durations post-training will impair memory consolidation irrespective of total sleep duration. When circadian-desynchronized animals are trained in a hippocampus-dependent contextual fear-conditioning task they show normal short-term memory but impaired long-term memory consolidation. This impairment in memory consolidation is positively associated with the post-training fragmentation of REM and NREM sleep but is not significantly associated with the fragmentation of total sleep or the total amount of delta activity. We also show that the sleep stage fragmentation resulting from circadian desynchrony has no effect on hippocampus-dependent spatial memory and no effect on hippocampus-independent cued fear-conditioning memory. Our findings in an intact animal model, in which sleep deprivation is not a confounding factor, support the hypothesis that the stereotypic sequence and duration of sleep stages play a specific role in long-term hippocampus-dependent fear memory consolidation. © 2016 Associated Professional Sleep Societies, LLC.
Thacher, Pamela V; Onyper, Serge V
To establish whether sleep, health, mood, behavior, and academics improved after a 45-minute delay in high school start time, and whether changes persisted longitudinally. We collected data from school records and student self-report across a number of domains at baseline (May 2012) and at two follow-up time points (November 2012 and May 2013), at a public high school in upstate New York. Students enrolled during academic years (AY) 2011-2012 and 2012-2013 completed the Pittsburgh Sleep Quality Index; the DASS-21; the "Owl-Lark" Scale; the Daytime Sleepiness Index; and a brief self-report of health. Reports from school records regarding attendance, tardiness, disciplinary violations, and academic performance were collected for AY 2010-2011 through 2013-2014. Students delayed but did not extend their sleep period; we found lasting improvements in tardiness and disciplinary violations after the start-time delay, but no changes to other variables. At the first follow-up, students reported 20 minutes longer sleep, driven by later rise times and stable bed times. At the second follow-up, students maintained later rise times but delayed bedtimes, returning total sleep to baseline levels. A delay in rise time, paralleling the delay in the start time that occurred, resulted in less tardiness and decreased disciplinary incidents, but larger improvements to sleep patterns may be necessary to affect health, attendance, sleepiness, and academic performance. Later start times improved tardiness and disciplinary issues at this school district. A delay in start time may be a necessary but not sufficient means to increase sleep time and may depend on preexisting individual differences. A commentary on this article appears in this issue on page 267. © 2016 Associated Professional Sleep Societies, LLC.
Buscemi, Dolores; Kumar, Ashwani; Nugent, Rebecca; Nugent, Kenneth
Study Objectives: Epidemiological studies have demonstrated an association between short sleep times and obesity as defined by body mass index (BMI). We wanted to determine whether this association occurs in patients with chronic medical diagnoses since the number of confounding factors is likely higher in patients than the general population. Methods: Two hundred patients attending internal medicine clinics completed a survey regarding sleep habits, lifestyle characteristics, and medical diagnoses. An independent surveyor collected the information on the questionnaires and reviewed the medical records. Height and weight were measured by clinic personnel. Data were analyzed with multivariate logistic regression. Results: Subjects with short sleep times (< 7 hours) had an increased likelihood of obesity as defined by a BMI ≥ 30 kg/m2 when compared to the reference group of (8, 9] hours (odds ratio 2.93; 95% confidence interval, 1.06–8.09). There was a U-shaped relationship between obesity and sleep time in women but not in men. Young age (18 to 49 years), not smoking, drinking alcohol, hypertension, diabetes, and sleep apnea were also associated with obesity in the overall model. Conclusions: This study demonstrates an association between short sleep times and obesity in undifferentiated patients attending an internal medicine clinic using models adjusting for age, lifestyle characteristics, and some medical diagnoses. The U-shaped relationship in women suggests that sleep patterns may have gender specific associations. These observations provide the background for therapeutic trials in weight loss in patients with established medical problems. Citation: Buscemi D; Kumar A; Nugent R; Nugent K. Short sleep times predict obesity in internal medicine clinic patients. J Clin Sleep Med 2007;3(7):681–688. PMID:18198800
G. and Tsotsos, J. K. Neurobiology of Attention. Elsevier Academic Press, Oxford, 2005. Jennings, J. R., Monk, T. H. and van der Molen , M. W. Sleep...education: 15.3 ± 1.6) free of medical and psychiatric disor- ders participated in this study after providing written informed consent. All subjects...fMRI activation during parametric variations of attentional load.Neuron, 2001, 32: 737–745. Doran, S. M., Van Dongen, H. P. A. and Dinges, D. F
Ramakrishnan, Sridhar; Laxminarayan, Srinivas; Thorsley, David; Wesensten, Nancy J; Balkin, Thomas J; Reifman, Jaques
Individual differences in vulnerability to sleep loss can be considerable, and thus, recent efforts have focused on developing individualized models for predicting the effects of sleep loss on performance. Individualized models constructed using a Bayesian formulation, which combines an individual's available performance data with a priori performance predictions from a group-average model, typically need at least 40 h of individual data before showing significant improvement over the group-average model predictions. Here, we improve upon the basic Bayesian formulation for developing individualized models by observing that individuals may be classified into three sleep-loss phenotypes: resilient, average, and vulnerable. For each phenotype, we developed a phenotype-specific group-average model and used these models to identify each individual's phenotype. We then used the phenotype-specific models within the Bayesian formulation to make individualized predictions. Results on psychomotor vigilance test data from 48 individuals indicated that, on average, ∼85% of individual phenotypes were accurately identified within 30 h of wakefulness. The percentage improvement of the proposed approach in 10-h-ahead predictions was 16% for resilient subjects and 6% for vulnerable subjects. The trade-off for these improvements was a slight decrease in prediction accuracy for average subjects.
Full Text Available The objective of this study was to evaluate enuretic events and its relations to sleep stages, sleep cycles and time durations in a selected group of children with primary essential sleep enuresis. We evaluated 18 patients with mean age of 8.2 years old (ranging from 5 to 12 years; 10 were males and 8 females (n.s.. They were referred to the Sleep Disorders Center with the specific complaint of enuresis since the first years of life (primary. Pediatric, urologic and neurologic workup did not show objective abnormalities (essential. The standard all-night polysomnography including an enuresis sensor attached to the shorts in the crotch area was performed. Only enuretic events nights were included. All were drug free patients for two weeks prior to polysomnography. In this report, only one polysomnography per patient was considered. The enuretic events were phase related, occurring predominantly in non-REM (NREM sleep (p<0.05. There was no predominance of enuretic events among the NREM stages (n.s.. A tendency of these events to occur in the first two sleep cycles was detected but may be due to the longer duration of these cycles. The events were time modulated, adjusted to a normal distribution with a mean of 213.4 min of recording time.
Minges, Karl E; Redeker, Nancy S
Many schools have instituted later morning start times to improve sleep, academic, and other outcomes in response to the mismatch between youth circadian rhythms and early morning start times. However, there has been no systematic synthesis of the evidence on the effects of this practice. To examine the impact of delayed school start time on students' sleep, health, and academic outcomes, electronic databases were systematically searched and data were extracted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Six studies satisfied selection criteria and used pre-post, no control (n = 3), randomized controlled trial (n = 2), and quasi-experimental (n = 1) designs. School start times were delayed 25-60 min, and correspondingly, total sleep time increased from 25 to 77 min per weeknight. Some studies revealed reduced daytime sleepiness, depression, caffeine use, tardiness to class, and trouble staying awake. Overall, the evidence supports recent non-experimental study findings and calls for policy that advocates for delayed school start time to improve sleep. This presents a potential long-term solution to chronic sleep restriction during adolescence. However, there is a need for rigorous randomized study designs and reporting of consistent outcomes, including objective sleep measures and consistent measures of health and academic performance. Copyright © 2015 Elsevier Ltd. All rights reserved.
Borniger, Jeremy C; Weil, Zachary M; Zhang, Ning; Nelson, Randy J
Artificial nighttime illumination has recently become commonplace throughout the world; however, in common with other animals, humans have not evolved in the ecological context of chronic light at night. With prevailing evidence linking the circadian, endocrine, immune, and metabolic systems, understanding these relationships is important to understanding the etiology and progression of several diseases. To eliminate the covariate of sleep disruption in light at night studies, researchers often use nocturnal animals. However, the assumption that light at night does not affect sleep in nocturnal animals remains unspecified. To test the effects of light at night on sleep, we maintained Swiss-Webster mice in standard light/dark (LD) or dim light at night (DLAN) conditions for 8-10 wks and then measured electroencephalogram (EEG) and electromyogram (EMG) biopotentials via wireless telemetry over the course of two consecutive days to determine differences in sleep timing and homeostasis. Results show no statistical differences in total percent time, number of episodes, maximum or average episode durations in wake, slow-wave sleep (SWS), or rapid eye movement (REM) sleep. No differences were evident in SWS delta power, an index of sleep drive, between groups. Mice kept in DLAN conditions showed a relative increase in REM sleep during the first few hours after the dark/light transition. Both groups displayed normal 24-h circadian rhythms as measured by voluntary running wheel activity. Groups did not differ in body mass, but a marked negative correlation of body mass with percent time spent awake and a positive correlation of body mass with time spent in SWS was evident. Elevated body mass was also associated with shorter maximum wake episode durations, indicating heavier animals had more trouble remaining in the wake vigilance state for extended periods of time. Body mass did not correlate with activity levels, nor did activity levels correlate with time spent in
Chauvat, Dominique; Bonnet, Christophe; Dunseath, Kevin; Emile, Olivier; Le Floch, Albert
We have identified for the first time the absolute delay at total reflection, envisioned by Newton. We show that there are in fact two divergent Wigner delays, depending on the polarisation of the incident light. These measurements give a new insight on the passage from total reflection to refraction
Nilsson, Emil K.; Bostr?m, Adrian E.; Mwinyi, Jessica; Schi?th, Helgi B.
Abstract Despite an established link between sleep deprivation and epigenetic processes in humans, it remains unclear to what extent sleep deprivation modulates DNA methylation. We performed a within-subject randomized blinded study with 16 healthy subjects to examine the effect of one night of total sleep deprivation (TSD) on the genome-wide methylation profile in blood compared with that in normal sleep. Genome-wide differences in methylation between both conditions were assessed by applyin...
Genzel, L; Ahrberg, K; Roselli, C; Niedermaier, S; Steiger, A; Dresler, M; Roenneberg, T
Overwhelming evidence supports the importance of sleep for memory consolidation. Medical students are often deprived of sufficient sleep due to large amounts of clinical duties and university load, we therefore investigated how study and sleep habits influence university performance. We performed a questionnaire-based study with 31 medical students of the University of Munich (second and third clinical semesters; surgery and internal medicine). The students kept a diary (in 30-min bins) on their daily schedules (times when they studied by themselves, attended classes, slept, worked on their thesis, or worked to earn money). The project design involved three 2-wk periods (A: during the semester; B: directly before the exam period--pre-exam; C: during the subsequent semester break). Besides the diaries, students completed once questionnaires about their sleep quality (Pittsburgh Sleep Quality Index [PSQI]), their chronotype (Munich Chronotype Questionnaire [MCTQ]), and their academic history (previous grades, including the previously achieved preclinical board exam [PBE]). Analysis revealed significant correlations between the actual sleep behavior during the semester (MS(diary); mid-sleep point averaged from the sleep diaries) during the pre-exam period and the achieved grade (p = 0.002) as well as between the grades of the currently taken exam and the PBE (p = 0.002). A regression analysis with MS(diary) pre-exam and PBE as predictors in a model explained 42.7% of the variance of the exam grade (effect size 0.745). Interestingly, MS(diary)--especially during the pre-exam period-was the strongest predictor for the currently achieved grade, along with the preclinical board exam as a covariate, whereas the chronotype did not significantly influence the exam grade.
Watson, Emily J; Coates, Alison M; Banks, Siobhan; Kohler, Mark
This study aimed to compare sugar intake in Australian children with current guidelines and determine if total sugar consumption as a percentage of energy (sugar %E) exacerbates the relationship between sleep and behaviour. A sample of 287 children aged 8-12 years (boys 48.8%, age: 10.7 ± 1.3 years), and their parents/guardians completed a battery of questionnaires. Children completed a food frequency questionnaire, and parents completed demographic, sleep, and behaviour questionnaires. Average sugar intake was 134.9 ± 71.7 g per day (sugar %E 26.0 ± 7.0%), and only 55 (19%) participants did not exceed the recommended sugar intake limit. Correlations and logistical regressions indicated that sugar %E was not associated with sleep or behavioural domains (r range = -0.07-0.08; p range = .173-.979) nor contributed to the prediction of sleep behaviour problems (p range = .16-.80). Whilst a high proportion of children consumed above the recommended amount of daily total sugar, total sugar consumption was not related to behavioural or sleep problems, nor affected the relationship between these variables.
Munazah F. Qureshi
Full Text Available The conditioning tasks have been widely used to model fear and anxiety and to study their association with sleep. Many reports suggest that sleep plays a vital role in the consolidation of fear memory. Studies have also demonstrated that fear-conditioning influences sleep differently in mice strains having a low or high anxiety level. It is, therefore, necessary to know, how sleep influences fear-conditioning and how fear-conditioning induces changes in sleep architecture in moderate anxious strains. We have used Swiss mice, a moderate anxious strain, to study the effects of: (i sleep deprivation on contextual fear conditioned memory, and also (ii contextual fear conditioning on sleep architecture. Animals were divided into three groups: (a non-sleep deprived (NSD; (b stress control (SC; and (c sleep-deprived (SD groups. The SD animals were SD for 5 h soon after training. We found that the NSD and SC animals showed 60.57% and 58.12% freezing on the testing day, while SD animals showed significantly less freezing (17.13% only; p < 0.001 on the testing day. Further, we observed that contextual fear-conditioning did not alter the total amount of wakefulness and non-rapid eye movement (NREM sleep. REM sleep, however, significantly decreased in NSD and SC animals on the training and testing days. Interestingly, REM sleep did not decrease in the SD animals on the testing day. Our results suggest that short-term sleep deprivation impairs fear memory in moderate anxious mice. It also suggests that NREM sleep, but not REM sleep, may have an obligatory role in memory consolidation.
Strangman, Gary; Thompson, John H.; Strauss, Monica M.; Marshburn, Thomas H.; Sutton, Jeffrey P.
Study Objectives: To assess the cerebral effects associated with sleep deprivation in a simulation of a complex, real-world, high-risk task. Design and Interventions: A two-week, repeated measures, cross-over experimental protocol, with counterbalanced orders of normal sleep (NS) and total sleep deprivation (TSD). Setting: Each subject underwent functional magnetic resonance imaging (fMRI) while performing a dual-joystick, 3D sensorimotor navigation task (simulated orbital docking). Scanning was performed twice per subject, once following a night of normal sleep (NS), and once following a single night of total sleep deprivation (TSD). Five runs (eight 24s docking trials each) were performed during each scanning session. Participants: Six healthy, young, right-handed volunteers (2 women; mean age 20) participated. Measurements and Results: Behavioral performance on multiple measures was comparable in the two sleep conditions. Neuroimaging results within sleep conditions revealed similar locations of peak activity for NS and TSD, including left sensorimotor cortex, left precuneus (BA 7), and right visual areas (BA 18/19). However, cerebral activation following TSD was substantially larger and exhibited higher amplitude modulations from baseline. When directly comparing NS and TSD, most regions exhibited TSD>NS activity, including multiple prefrontal cortical areas (BA 8/9,44/45,47), lateral parieto-occipital areas (BA 19/39, 40), superior temporal cortex (BA 22), and bilateral thalamus and amygdala. Only left parietal cortex (BA 7) demonstrated NS>TSD activity. Conclusions: The large network of cerebral differences between the two conditions, even with comparable behavioral performance, suggests the possibility of detecting TSD-induced stress via functional brain imaging techniques on complex tasks before stress-induced failures.
Hilditch, Cassie J; Dorrian, Jillian; Banks, Siobhan
Sleep inertia is the period of impaired performance and grogginess experienced after waking. This period of impairment is of concern to workers who are on-call, or nap during work hours, and need to perform safety-critical tasks soon after waking. While several studies have investigated the best sleep timing and length to minimise sleep inertia effects, few have focused on countermeasures -especially those that can be implemented after waking (i.e. reactive countermeasures). This structured review summarises current literature on reactive countermeasures to sleep inertia such as caffeine, light, and temperature and discusses evidence for the effectiveness and operational viability of each approach. Current literature does not provide a convincing evidence-base for a reactive countermeasure. Caffeine is perhaps the best option, although it is most effective when administered prior to sleep and is therefore not strictly reactive. Investigations into light and temperature have found promising results for improving subjective alertness; further research is needed to determine whether these countermeasures can also attenuate performance impairment. Future research in this area would benefit from study design features highlighted in this review. In the meantime, it is recommended that proactive sleep inertia countermeasures are used, and that safety-critical tasks are avoided immediately after waking.
Full Text Available Interactions between large-scale brain networks have received most attention in the study of cognitive dysfunction of human brain. In this paper, we aimed to test the hypothesis that the coupling strength of large-scale brain networks will reflect the pressure for sleep and will predict cognitive performance, referred to as sleep pressure index (SPI. Fourteen healthy subjects underwent this within-subject functional magnetic resonance imaging (fMRI study during rested wakefulness (RW and after 36 h of total sleep deprivation (TSD. Self-reported scores of sleepiness were higher for TSD than for RW. A subsequent working memory (WM task showed that WM performance was lower after 36 h of TSD. Moreover, SPI was developed based on the coupling strength of salience network (SN and default mode network (DMN. Significant increase of SPI was observed after 36 h of TSD, suggesting stronger pressure for sleep. In addition, SPI was significantly correlated with both the visual analogue scale score of sleepiness and the WM performance. These results showed that alterations in SN-DMN coupling might be critical in cognitive alterations that underlie the lapse after TSD. Further studies may validate the SPI as a potential clinical biomarker to assess the impact of sleep deprivation.
Rošt'áková, Zuzana; Rosipal, Roman
Sleep can be characterised as a dynamic process that has a finite set of sleep stages during the night. The standard Rechtschaffen and Kales sleep model produces discrete representation of sleep and does not take into account its dynamic structure. In contrast, the continuous sleep representation provided by the probabilistic sleep model accounts for the dynamics of the sleep process. However, analysis of the sleep probabilistic curves is problematic when time misalignment is present. In this study, we highlight the necessity of curve synchronisation before further analysis. Original and in time aligned sleep probabilistic curves were transformed into a finite dimensional vector space, and their ability to predict subjects' age or daily measures is evaluated. We conclude that curve alignment significantly improves the prediction of the daily measures, especially in the case of the S2-related sleep states or slow wave sleep.
Oonk, Marcella; Davis, Christopher J; Krueger, James M; Wisor, Jonathan P; Van Dongen, Hans P A
The rat psychomotor vigilance task (rPVT) was developed as a rodent analog of the human psychomotor vigilance task (hPVT). We examined whether rPVT performance displays time-on-task effects similar to those observed on the hPVT. The rPVT requires rats to respond to a randomly presented light stimulus to obtain a water reward. Rats were water deprived for 22 h prior to each 30-min rPVT session to motivate performance. We analyzed rPVT performance over time on task and as a function of the response-stimulus interval, at baseline and after sleep deprivation. The study was conducted in an academic research vivarium. Male Long-Evans rats were trained to respond to a 0.5 sec stimulus light within 3 sec of stimulus onset. Complete data were available for n = 20 rats. Rats performed the rPVT for 30 min at baseline and after 24 h total sleep deprivation by gentle handling. Compared to baseline, sleep deprived rats displayed increased performance lapses and premature responses, similar to hPVT lapses of attention and false starts. However, in contrast to hPVT performance, the time-on-task performance decrement was not significantly enhanced by sleep deprivation. Moreover, following sleep deprivation, rPVT response times were not consistently increased after short response-stimulus intervals. The rPVT manifests similarities to the hPVT in global performance outcomes, but not in post-sleep deprivation effects of time on task and response-stimulus interval. © 2015 Associated Professional Sleep Societies, LLC.
Lo, June C.; Groeger, John A.; Santhi, Nayantara; Arbon, Emma L.; Lazar, Alpar S.; Hasan, Sibah; von Schantz, Malcolm; Archer, Simon N.; Dijk, Derk-Jan
Background Cognitive performance deteriorates during extended wakefulness and circadian phase misalignment, and some individuals are more affected than others. Whether performance is affected similarly across cognitive domains, or whether cognitive processes involving Executive Functions are more sensitive to sleep and circadian misalignment than Alertness and Sustained Attention, is a matter of debate. Methodology/Principal Findings We conducted a 2 × 12-day laboratory protocol to characterize the interaction of repeated partial and acute total sleep deprivation and circadian phase on performance across seven cognitive domains in 36 individuals (18 males; mean ± SD of age = 27.6±4.0 years). The sample was stratified for the rs57875989 polymorphism in PER3, which confers cognitive susceptibility to total sleep deprivation. We observed a deterioration of performance during both repeated partial and acute total sleep deprivation. Furthermore, prior partial sleep deprivation led to poorer cognitive performance in a subsequent total sleep deprivation period, but its effect was modulated by circadian phase such that it was virtually absent in the evening wake maintenance zone, and most prominent during early morning hours. A significant effect of PER3 genotype was observed for Subjective Alertness during partial sleep deprivation and on n-back tasks with a high executive load when assessed in the morning hours during total sleep deprivation after partial sleep loss. Overall, however, Subjective Alertness and Sustained Attention were more affected by both partial and total sleep deprivation than other cognitive domains and tasks including n-back tasks of Working Memory, even when implemented with a high executive load. Conclusions/Significance Sleep loss has a primary effect on Sleepiness and Sustained Attention with much smaller effects on challenging Working Memory tasks. These findings have implications for understanding how sleep debt and circadian rhythmicity
Sauvet, Fabien; Arnal, Pierrick J; Tardo-Dino, Pierre Emmanuel; Drogou, Catherine; Van Beers, Pascal; Bougard, Clément; Rabat, Arnaud; Dispersyn, Garance; Malgoyre, Alexandra; Leger, Damien; Gomez-Merino, Danielle; Chennaoui, Mounir
Sleep loss is a risk factor for cardiovascular events mediated through endothelial dysfunction. To determine if 7weeks of exercise training can limit cardiovascular dysfunction induced by total sleep deprivation (TSD) in healthy young men. 16 subjects were examined during 40-h TSD, both before and after 7weeks of interval exercise training. Vasodilatation induced by ACh, insulin and heat (42°C) and pulse wave velocity (PWV), blood pressure and heart rate (HR) were assessed before TSD (controlday), during TSD, and after one night of sleep recovery. Biomarkers of endothelial activation, inflammation, and hormones were measured from morning blood samples. Before training, ACh-, insulin- and heat-induced vasodilatations were significantly decreased during TSD and recovery as compared with the control day, with no difference after training. Training prevented the decrease of ACh-induced vasodilation related to TSD after sleep recovery, as well as the PWV increase after TSD. A global lowering effect of training was found on HR values during TSD, but not on blood pressure. Training induces the decrease of TNF-α concentration after TSD and prevents the increase of MCP-1 after sleep recovery. Before training, IL-6 concentrations increased. Cortisol and testosterone decreased after TSD as compared with the control day, while insulin and E-selectin increased after sleep recovery. No effect of TSD or training was found on CRP and sICAM-1. In healthy young men, a moderate to high-intensity interval training is effective at improving aerobic fitness and limiting vascular dysfunction induced by TSD, possibly through pro-inflammatory cytokine responses.(ClinicalTrial:NCT02820649). Copyright Â© 2017 Elsevier B.V. All rights reserved.
Nordin, Maria; Kaplan, Robert M
To investigate the impact of development in sleep continuity on transition to and from obesity over time. The study used self-reported sleep and body mass index (BMI) measures from the 1965, 1974, 1983, and 1994 waves of the longitudinal Alameda County Study. Sleep continuity was assessed by a question on whether the participants had any troubles falling or staying asleep. Change in sleep and BMI were estimated from the sleep and BMI questions in 1965 and 1994 respectively. Multinomial regression analyses were used to examine the risk/chance for a transition to and from obesity (BMI >or=30 kg/m(2)) due to development in sleep continuity. After adjustment for confounding variables, consistent sleep discontinuity both increases the risk for a transition to obesity and reduces the chance of losing weight, whereas impaired sleep continuity lowers the chance for weight loss. Effects for obesity were non-significant for those with improved sleep continuity. Consistent sleep discontinuity and impaired sleep continuity increases the risk of transition to obesity or of remaining obese.
Basner, Mathias; Fomberstein, Kenneth M; Razavi, Farid M; Banks, Siobhan; William, Jeffrey H; Rosa, Roger R; Dinges, David F
To gain some insight into how various behavioral (lifestyle) factors influence sleep duration, by investigation of the relationship of sleep time to waking activities using the American Time Use Survey (ATUS). Cross-sectional data from ATUS, an annual telephone survey of a population sample of US citizens who are interviewed regarding how they spent their time during a 24-hour period between 04:00 on the previous day and 04:00 on the interview day. Data were pooled from the 2003, 2004, and 2005 ATUS databases involving N=47,731 respondents older than 14 years of age. N/A. Adjusted multiple linear regression models showed that the largest reciprocal relationship to sleep was found for work time, followed by travel time, which included commute time. Only shorter than average sleepers (socializing, relaxing, and engaging in leisure activities, while both short ( or =8.5 h) watched more TV than the average sleeper. The extent to which sleep time was exchanged for waking activities was also shown to depend on age and gender. Sleep time was minimal while work time was maximal in the age group 45-54 yr, and sleep time increased both with lower and higher age. Work time, travel time, and time for socializing, relaxing, and leisure are the primary activities reciprocally related to sleep time among Americans. These activities may be confounding the frequently observed association between short and long sleep on one hand and morbidity and mortality on the other hand and should be controlled for in future studies.
Goulart, Leonardo I; Pinto, Luciano R; Perlis, Michael L; Martins, Raquel; Caboclo, Luis Otavio; Tufik, Sergio; Andersen, Monica L
To investigate whether different protocols of sleep deprivation modify sleep perception. The effects of total sleep deprivation (TD) and selective rapid eye movement (REM) sleep deprivation (RD) on sleep perception were analyzed in normal volunteers. Thirty-one healthy males with normal sleep were randomized to one of three conditions: (i) normal uninterrupted sleep; (ii) four nights of RD; or (iii) two nights of TD. Morning perception of total sleep time was evaluated for each condition. Sleep perception was estimated using total sleep time (in hours) as perceived by the volunteer divided by the total sleep time (in hours) measured by polysomnography (PSG). The final value of this calculation was defined as the perception index (PI). There were no significant differences among the three groups of volunteers in the total sleep time measured by PSG or in the perception of total sleep time at baseline condition. Volunteers submitted to RD exhibited lower sleep PI scores as compared with controls during the sleep deprivation period (P sleep deprivation reduced the ability of healthy young volunteers to perceive their total sleep time when compared with time measured by PSG. The data reinforce the influence of sleep deprivation on sleep perception. Copyright © 2014 Elsevier B.V. All rights reserved.
Meijer, A M; Habekothé, H T; Van Den Wittenboer, G L
This study describes the relationship of time in bed and quality of sleep with concentration and functioning at school. Neurotic and psychosomatic symptoms have been used as control variables. The sample consisted of 449 Dutch children in the seventh and eighth grades of elementary school. The age of the children varied between 9 y 5 mo and 14 y 5 mo. Seven schools participated in the research, with a total of 18 classes. The results indicated that 43% of the children had difficulty getting up in the morning. Furthermore, 15% of the children reported sleep problems and 25% did not feel rested at school. Time in bed and sleep quality show no relationship with concentration. Sleep quality, feeling rested at school and less distinct bedtimes were clearly related to school functioning. Another result was that children who had no difficulty getting up displayed more achievement motivation. Being open to the teacher's influence and achievement motivation depended mainly on sleep characteristics. Not getting bored at school, self-image as a pupil and control over aggressive behaviour were also influenced by gender, age, neuroticism and neurosomaticism.
... Institute (NHLBI). 1 Mood. Sleep affects your mood. Insufficient sleep can cause irritability that can lead to trouble with relationships, ... basics/understanding_sleep.htm#dynamic_activity Centers for Disease ... insufficient rest or sleep among adults—United States, 2008. MMWR, 58 (42), ...
Kline, Christopher E; Krafty, Robert T; Mulukutla, Suresh; Hall, Martica H
The purpose of this study was to evaluate the relationship between daytime activity (sedentary time, moderate- to vigorous-intensity physical activity [MVPA]) and indices of polysomnographically (PSG) assessed sleep, including sleep-disordered breathing (SDB). One hundred and thirty-six adults (65% female, 59.8 ± 9.1 years, body mass index [BMI] 30.3 ± 6.9 kg m -2 ) provided daily estimates of time spent in light-, moderate-, and vigorous-intensity activity for 6-14 days (mean 9.9 ± 1.8 days) prior to laboratory PSG. Daily sedentary time was calculated as the amount of time spent awake and not in light-, moderate-, or vigorous-intensity activity; time spent in moderate- and vigorous-intensity activity were combined for MVPA. Indices of PSG sleep included timing (sleep midpoint), duration (total sleep time), continuity (sleep efficiency), depth (% slow-wave sleep), and SDB (apnea-hypopnea index [AHI]). Using median splits of sedentary time and MVPA, analyses of covariance examined their relationship with sleep following adjustment for age, sex, race, employment, education, BMI, existing cardiovascular disease, depression history, and mean daily wake time. Binary logistic regression examined the odds of having at least mild-severity SDB (AHI ≥ 5) according to sedentary time, MVPA, and their combination. Adults with above-median sedentary time (i.e., >841.9 min/day) had significantly greater AHI (P = .04) and lower odds of mild SDB (P = .03) compared to adults with low sedentary time; adults with high MVPA (>30.5 min/day) had significantly lower AHI compared to adults with low MVPA (P = .04). When examined in the same model, adults with high sedentary time and low MVPA had significantly higher AHI (P < .01) and higher odds of having mild SDB (P = .03) than all the other groups. No other sleep measures were related to sedentary time, MVPA, or their combination. Sedentary time and MVPA were associated with SDB. Whether reducing sedentary
Full Text Available The phenomenon of sleep is an active nervous and biologic rhythm, which is under influence of neurotransmitters of central nervous system. In this study, the influence of serotonergic system on sleeping time have been assessed by agonist-antagonist drugs using two methods of induction and non-induction behavioral and electrophysiology. The method used for measurement of total sleeing time was Angle method. For assessment of drugs impact on brain waves, after opening two holes in frontal and temporal regions, two non-polarized silvery electrodes were fixed in above regions and was connected to physiograph and computer by linkers for waves analysis. Injection intra-ventriculary is done by stereotax apparatus. Results indicate that diazepam (2.5 mg/kg increases sleeping time in two stages of induction and non-induction (P<0.01. 5-HTP (15, 45 mg/kg increases dose-dependence sleeping time. p-CPA (150, 300 mg/kg shows biphasic influence on sleeping time. The 300 mg/kg dose of p-CPA reduces sleeping time while 150 mg/kg dose inverts sleeping time (P<0.05. Interferential affects of drugs with (5-HTP 45 mg/kg and p-CPA (300 mg/kg doses are similar to control groups. Injection of 5-HTP inverts p-CPA affect. Intra-ventriculary Injection of 5-HTP in 150 µg/kg and 300 µg/kg doses, decreases frequency of delta waves and significantly increases the frequencies of other waves but conversely, 500 µg/kg decreases it. Due to findings of this study, interferential affects of agonist-antagonist of 5-HTP, can not invert p-CPA affect. Supported by GABA affects, diazepam induces its inhibitory affect in per-synaptic and post-synaptic membrane through ascending reticular both systems and blocking stimulation of brain cortical and limbic system. Affects of two other drugs on sleeping time and brain waves are probably caused by increment of released serotonin in pre-synaptic neurons. Although their interferential affects with other neurotransmitter system should be
Chan, Sze-Hang; Lam, Tak-Wah; Lee, Lap Kei
In large data centers, determining the right number of operating machines is often non-trivial, especially when the workload is unpredictable. Using too many machines would waste energy, while using too few would affect the performance. This paper extends the traditional study of online flow-time...... scheduling on multiple machines to take sleep management and energy into consideration. Specifically, we study online algorithms that can determine dynamically when and which subset of machines should wake up (or sleep), and how jobs are dispatched and scheduled. We consider schedules whose objective...... is to minimize the sum of flow time and energy, and obtain O(1)-competitive algorithms for two settings: one assumes machines running at a fixed speed, and the other allows dynamic speed scaling to further optimize energy usage. Like the previous work on the tradeoff between flow time and energy, the analysis...
Pereira, Erico Felden; Moreno, Claudia; Louzada, Fernando Mazzilli
Active travel to school has been referred to as one way of increasing the level of daily physical exercise, but the actual impacts on student's general health are not clear. Recently, a possible association between active travel to school and the duration of sleep was suggested. Thus, the aim was of this study to investigate the associations between the type of transportation and travel time to school, the time in bed and sleepiness in the classroom of high school students. Information on sleeping habits and travel to school of 1126 high school students were analyzed, where 55.1% were girls with an average age of 16.24 (1.39) years old, in Santa Maria Municipality, Rio Grande do Sul, Brazil. Multiple linear regression and adjusted prevalence rates analyses were carried out. The frequency of active travel found was 61.8%. Associations between time in bed, sleepiness in the classroom and the type of transportation (active or passive) were not identified. Nevertheless, the time in bed was inversely associated with the travel time (p = 0.036) and with a phase delay. In the adjusted analysis, active travel was more incident for the students of schools in the suburbs (PR: 1.68; CI: 1.40-2.01) in comparison with the students of schools in the center. Therefore, longer trips were associated with a reduction of sleep duration of morning and night groups. Interventions concerning active travel to school must be carried out cautiously in order not to cause a reduction of the sleeping time.
Nilsson, Emil K; Boström, Adrian E; Mwinyi, Jessica; Schiöth, Helgi B
Despite an established link between sleep deprivation and epigenetic processes in humans, it remains unclear to what extent sleep deprivation modulates DNA methylation. We performed a within-subject randomized blinded study with 16 healthy subjects to examine the effect of one night of total sleep deprivation (TSD) on the genome-wide methylation profile in blood compared with that in normal sleep. Genome-wide differences in methylation between both conditions were assessed by applying a paired regression model that corrected for monocyte subpopulations. In addition, the correlations between the methylation of genes detected to be modulated by TSD and gene expression were examined in a separate, publicly available cohort of 10 healthy male donors (E-GEOD-49065). Sleep deprivation significantly affected the DNA methylation profile both independently and in dependency of shifts in monocyte composition. Our study detected differential methylation of 269 probes. Notably, one CpG site was located 69 bp upstream of ING5, which has been shown to be differentially expressed after sleep deprivation. Gene set enrichment analysis detected the Notch and Wnt signaling pathways to be enriched among the differentially methylated genes. These results provide evidence that total acute sleep deprivation alters the methylation profile in healthy human subjects. This is, to our knowledge, the first study that systematically investigated the impact of total acute sleep deprivation on genome-wide DNA methylation profiles in blood and related the epigenomic findings to the expression data.
Jeoung A Kwon
Full Text Available Allergic rhinitis (AR is the most common chronic disorder in the pediatric population. Although several studies have investigated the correlation between AR and sleep-related issues, the association between the duration and time of sleep and AR has not been analyzed in long-term national data. This study investigated the relationship between sleep time and duration and AR risk in middle- and high-school students (adolescents aged 12-18. We analyzed national data from the Korea Youth Risk Behavior Web-based Survey by the Korea Centers for Disease Control and Prevention from 2007-2012. The sample size was 274,480, with an average response rate of 96.2%. Multivariate logistic regression analyses were conducted to determine the relationship between sleep and AR risk. Furthermore, to determine the best-fitted model among independent variables such as sleep duration, sleep time, and the combination of sleep duration and sleep time, we used Akaike Information Criteria (AIC to compare models. A total of 43,337 boys and 41,665 girls reported a diagnosis of AR at baseline. The odds ratio increased with age and with higher education and economic status of the parents. Further, students in mid-sized and large cities had stronger relationships to AR than those in small cities. In both genders, AR was associated with depression and suicidal ideation. In the analysis of sleep duration and sleep time, the odds ratio increased in both genders when sleep duration was <7 hours, and when the time of sleep was later than 24:00 hours. Our results indicate an association between sleep time and duration and AR. This study is the first to focus on the relationship between sleep duration and time and AR in national survey data collected over 6 years.
Spengler, Susan E; Browning, Steven R; Reed, Deborah B
Part-time farmers who hold off-farm jobs may be at risk for injuries because of impaired performance resulting from inadequate sleep. For this study, 1004 part-time male Kentucky farmers completed a telephone interview for the 1994 to 1995 National Institute for Occupational Safety and Health-funded Farm Family Health and Hazard Surveillance Project. Questions were included about demographics, sleep habits, and injury occurrence. Twelve percent of the farmers reported an injury requiring medical intervention in the previous year. Farmers reported sleeping an average of 7.6 hours daily. Approximately 6.7% of the sample had three symptoms of sleep apnea. Although hours of sleep were not related to injury incidence, sleep medication use (odds ratio [OR] = 2.11, 95% confidence interval [CI] = 1.01 to 4.40) and presence of three sleep apnea symptoms (OR = 2.48, 95% CI = 1.13 to 5.41) were related to injury incidence. These data support the need for further research to examine sleep habits and promote strategies that reduce the risk for injuries caused by lack of sleep.
Laurson, Kelly R; Lee, Joey A; Gentile, Douglas A; Walsh, David A; Eisenmann, Joey C
Aim. To examine the simultaneous influence of physical activity, screen time, and sleep duration recommendations on the odds of childhood obesity (including overweight). Methods. Physical activity was assessed via pedometer and screen time, and sleep duration were assessed via survey in a cross sectional sample of 674 children (aged 7-12 years) from two Midwestern communities in the fall of 2005. Participants were cross tabulated into four groups depending on how many recommendations were being met (0, 1, 2, or all 3). Linear and logistic regression were used to examine the influence of physical activity, screen time and sleep duration on obesity and interactions among the three variables. Results. Children achieving all three recommendations simultaneously (9.2% of total sample) were the least likely to be obese. Approximately 16% of boys and 9% of girls achieving all recommendations were overweight or obese compared to 53% of boys and 42.5% of girls not achieving any. Conclusions. The odds of obesity increased in a graded manner for each recommendation which was not met. Meeting all three recommendations appears to have a protective effect against obesity. Continued efforts are warranted to promote healthy lifestyle behaviors that include meeting physical activity, screen time, and sleep duration recommendations concurrently.
Full Text Available Sławomir Kujawski,1 Joanna Słomko,1 Małgorzata Tafil-Klawe,2 Monika Zawadka-Kunikowska,1 Justyna Szrajda,1 Julia L Newton,3 Paweł Zalewski,1 Jacek J Klawe1 1Department of Hygiene, Epidemiology and Ergonomics, Nicolaus Copernicus University, Toruń, Poland; 2Department of Human Physiology, Nicolaus Copernicus University, Toruń, Poland; 3Institute for Cellular Medicine, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle-upon-Tyne, UK Introduction: Firefighters as a profession are required to maintain high levels of attention for prolonged periods. However, total sleep deprivation (TSD could influence negatively upon performance, particularly when the task is prolonged and repetitive. Purpose: The aim of this study is to examine the influence of TSD on cognitive functioning in a group of firefighters. Subjects and methods: Sixty volunteers who were active male fire brigade officers were examined with a computerized battery test that consisted of simple reaction time (SRT (repeated three times, choice reaction time, visual attention test, and delayed matching to sample. Six series of measurements were undertaken over a period of TSD. Results: Performance in the second attempt in SRT test was significantly worse in terms of increased number of errors and, consequently, decreased number of correct responses during TSD. In contrast, the choice reaction time number of correct responses as well as the visual attention test reaction time for all and correct responses significantly improved compared to initial time points. Conclusion: The study has confirmed that subjects committed significantly more errors and, consequently, noted a smaller number of correct responses in the second attempt of SRT test. However, the remaining results showed reversed direction of TSD influence. TSD potentially leads to worse performance in a relatively easy task in a group of firefighters. Errors during repetitive tasks in firefighting
Hagen, Erika W.; Mirer, Anna G.; Palta, Mari; Peppard, Paul E.
Insufficient sleep is associated with poor health and increased mortality. Studies on whether parenthood (including consideration of number and ages of children) is associated with sleep duration or sleep problems are scant and inconclusive. Using data collected in the Wisconsin Sleep Cohort Study (n = 4,809) between 1989 and 2008, we examined cross-sectional associations of number and ages of children with self-reported parental sleep duration, daytime sleepiness, and dozing among employed adults. Longitudinal change in sleep duration over 19 years was examined to evaluate changes in parental sleep associated with children transitioning into adulthood (n = 833). Each child under age 2 years was associated with 13 fewer minutes of parental sleep per day (95% confidence interval (CI): 5, 21); each child aged 2–5 years was associated with 9 fewer minutes of sleep (95% CI: 5, 13); and each child aged 6–18 years was associated with 4 fewer minutes (95% CI: 2, 6). Adult children were not associated with shorter parental sleep duration. Parents of children over age 2 years were significantly more likely to experience daytime sleepiness and dozing during daytime activities. Parents of minor children at baseline had significantly greater increases in sleep duration over 19 years of follow-up. Parenting minor children is associated with shorter sleep duration. As children age into adulthood, the sleep duration of parents with more children approaches that of parents with fewer children. PMID:23378502
Kwon, Jeoung A; Lee, Minjee; Yoo, Ki-Bong; Park, Eun-Cheol
Allergic rhinitis (AR) is the most common chronic disorder in the pediatric population. Although several studies have investigated the correlation between AR and sleep-related issues, the association between the duration and time of sleep and AR has not been analyzed in long-term national data. This study investigated the relationship between sleep time and duration and AR risk in middle- and high-school students (adolescents aged 12-18). We analyzed national data from the Korea Youth Risk Behavior Web-based Survey by the Korea Centers for Disease Control and Prevention from 2007-2012. The sample size was 274,480, with an average response rate of 96.2%. Multivariate logistic regression analyses were conducted to determine the relationship between sleep and AR risk. Furthermore, to determine the best-fitted model among independent variables such as sleep duration, sleep time, and the combination of sleep duration and sleep time, we used Akaike Information Criteria (AIC) to compare models. A total of 43,337 boys and 41,665 girls reported a diagnosis of AR at baseline. The odds ratio increased with age and with higher education and economic status of the parents. Further, students in mid-sized and large cities had stronger relationships to AR than those in small cities. In both genders, AR was associated with depression and suicidal ideation. In the analysis of sleep duration and sleep time, the odds ratio increased in both genders when sleep duration was sleep was later than 24:00 hours. Our results indicate an association between sleep time and duration and AR. This study is the first to focus on the relationship between sleep duration and time and AR in national survey data collected over 6 years.
The extent to which work hours and sleep are associated with self-rated health (SRH) was investigated in full-time employees of small- and medium-scale businesses (SMBs) in a suburb of Tokyo. A total of 2,579 employees (1,887 men and 692 women), aged 18-79 (mean 45) years, in 296 SMBs were surveyed using a self-administered questionnaire from August to December 2002. Work hours, sleep, and SRH were evaluated. Compared with those working 6-8 h/day, participants working >8 to 10 h/day and >10 h/day had significantly higher odds of suboptimal SRH [adjusted odds ratio (aOR) 1.36 and 1.87, respectively]. Similarly, compared with those sleeping 6+ h/day and sufficient sleep, participants with short sleep (work hours with short sleep (aOR 3.30) or insufficient sleep (aOR 3.40) exerted synergistic negative associations on SRH. This study suggests that long work hours and poor sleep and its combination are associated with suboptimal SRH.
ENNIO A VIVALDI
Full Text Available A computer-based system that automates sleep studies, including sleep deprivation paradigms, is described. The system allows for total or REM-specific sleep deprivation and is based on a reliable, fast-responding, on-line state detection algorithm linked to a dependable intervention device. Behavioral state detection is achieved by dimensión reduction of short-term EEG power spectrum. Interventions are made by serial outputs to servomotors that move a cage with different patterns and variable intensity. The system can adapt itself to individual characteristics and to changes in recording conditions. Customized protocols can be designed by defining the states or stages to be deprived, including scheduling temporal patterns. A detailed analysis of the relevant signáis during and after deprivation is readily available. Data is presented from two experimental designs in rats. One consisted of specific REM-sleep short-term deprivation and the other of 10-hour total sleep deprivation. An outline of conceptual and practical considerations involved in the automation of laboratory set-ups oriented to biosignal analysis is provided. Careful monitoring of sleep EEG variables during sleep deprivation suggests peculiarities of brain functioning in that condition. A corollary is that sleep deprivation should not be considered to be merely a forced prolonged wakefulness.
Tavernier, Royette; Heissel, Jennifer A; Sladek, Michael R; Grant, Kathryn E; Adam, Emma K
The present study examined both within- and between-person associations between adolescents' time use (technology-based activities and face-to-face interactions with friends and family) and sleep behaviors. We also assessed whether age moderated associations between adolescents' time use with friends and family and sleep. Adolescents wore an actigraph monitor and completed brief evening surveys daily for 3 consecutive days. Adolescents (N=71; mean age=14.50 years old, SD=1.84; 43.7% female) were recruited from 3 public high schools in the Midwest. We assessed 8 technology-based activities (eg, texting, working on a computer), as well as time spent engaged in face-to-face interactions with friends and family, via questions on adolescents' evening surveys. Actigraph monitors assessed 3 sleep behaviors: sleep latency, sleep hours, and sleep efficiency. Hierarchical linear models indicated that texting and working on the computer were associated with shorter sleep, whereas time spent talking on the phone predicted longer sleep. Time spent with friends predicted shorter sleep latencies, while family time predicted longer sleep latencies. Age moderated the association between time spent with friends and sleep efficiency, as well as between family time and sleep efficiency. Specifically, longer time spent interacting with friends was associated with higher sleep efficiency but only among younger adolescents. Furthermore, longer family time was associated with higher sleep efficiency but only for older adolescents. Findings are discussed in terms of the importance of regulating adolescents' technology use and improving opportunities for face-to-face interactions with friends, particularly for younger adolescents. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.
... the day, even if you have had enough sleep? You might have a sleep disorder. The most common kinds are Insomnia - a hard time falling or staying asleep Sleep apnea - breathing interruptions during sleep Restless legs syndrome - ...
Sasazawa, Y.; Kawada, T.; Kiryu, Y.
This study was designed to assess the effects of daytime physical exercise on the quality of objective and subjective sleep by examining all-night sleep EEGs. The subjects were five male students, aged 19 to 20 years, who were in the habit of performing regular daytime exercise. The sleep polygraphic parameters in this study were sleep stage time as a percentage of total sleep time (%S1, %S2, %S(3+4), %SREM, %MT), time in bed (TIB), sleep time (ST), total sleep time (TST), sleep onset latency (SOL), waking from sleep, sleep efficiency, number of awakenings, number of stage shifts, number of spindles, and percentages of α and δ waves, all of which were determined by an automatic computer analysis system. The OSA questionnaire was used to investigate subjective sleep. The five scales of the OSA used were sleepiness, sleep maintenance, worry, integrated sleep feeling, and sleep initiation. Each sleep parameter was compared in the exercise and the non-exercise groups. Two-way analysis of variance was applied using subject factor and exercise factor. The main effect of the subject was significant in all parameters and the main effect of exercise in %S(3+4), SOL and sleep efficiency, among the objective sleep parameters. The main effects of the subject, except sleepiness, were significant, as was the main effect of exercise on sleep initiation, among the subjective sleep parameters. These findings suggest that daytime exercise shortened sleep latency and prolonged slow-wave sleep, and that the subjects fell asleep more easily on exercise days. There were also significant individual differences in both the objective and subjective sleep parameters.
Gong, Long; Wang, ZhenHu; Fan, Dong
This study examined the effects of sleep quality on early recovery after total knee arthroplasty. A total of 148 patients were randomized 1:1 to receive either zolpidem or placebo for 2 weeks. VAS pain scores (rest, ambulation and night), range of motion (ROM), total amount of opioid analgesics and antiemetics taken, postoperative nausea and vomiting (PONV), sleep efficacy and satisfaction were recorded. It was found that patients taking zolpidem achieved greater improvement in quality of life and reported better satisfaction. Patients in the intervention group had lower pain score and took less antiemetics. Moreover, a significant correlation between sleep quality and ROM was detected. These results demonstrated that improved sleep quality is beneficial to patients' post-TKA recovery. Copyright © 2015. Published by Elsevier Inc.
Zhuo Zhang; Cuntai Guan; Ti Eu Chan; Juanhong Yu; Aung Aung Phyo Wai; Chuanchu Wang; Haihong Zhang
We developed an EEG- and audio-based sleep sensing and enhancing system, called iSleep (interactive Sleep enhancement apparatus). The system adopts a closed-loop approach which optimizes the audio recording selection based on user's sleep status detected through our online EEG computing algorithm. The iSleep prototype comprises two major parts: 1) a sleeping mask integrated with a single channel EEG electrode and amplifier, a pair of stereo earphones and a microcontroller with wireless circuit for control and data streaming; 2) a mobile app to receive EEG signals for online sleep monitoring and audio playback control. In this study we attempt to validate our hypothesis that appropriate audio stimulation in relation to brain state can induce faster onset of sleep and improve the quality of a nap. We conduct experiments on 28 healthy subjects, each undergoing two nap sessions - one with a quiet background and one with our audio-stimulation. We compare the time-to-sleep in both sessions between two groups of subjects, e.g., fast and slow sleep onset groups. The p-value obtained from Wilcoxon Signed Rank Test is 1.22e-04 for slow onset group, which demonstrates that iSleep can significantly reduce the time-to-sleep for people with difficulty in falling sleep.
Genzel, L.K.E.; Ahrberg, K.; Roselli, C.; Niedermaier, S.; Steiger, A.; Dresler, M.; Roenneberg, T.
Overwhelming evidence supports the importance of sleep for memory consolidation. Medical students are often deprived of sufficient sleep due to large amounts of clinical duties and university load, we therefore investigated how study and sleep habits influence university performance. We performed a
van Gilst, Merel M; Louter, Maartje; Baumann, Christian R; Bloem, Bastiaan R; Overeem, Sebastiaan
Some patients with Parkinson's disease (PD) reportedly experience 'sleep benefit': an improved motor functioning upon awaking in the morning. In this questionnaire study, 114 out of 243 consecutive outpatients with PD (46.9%) subjectively experienced sleep benefit. Among those patients that regularly took an afternoon nap, 33.7% experienced sleep benefit after the nap as well. Between patients with and without sleep benefit, there were no differences in demographic or clinical variables, including age, disease duration, dopaminergic treatment, and nocturnal sleep quality. Sleep benefit remains an intriguing but elusive phenomenon, which deserves renewed attention and further research.
Drummond, Sean P
.... Although considerable data show that sleep deprivation alters many aspects of behavior, little is known about changes in the brain substrate underlying the behavioral effects, and even less is known...
Bothelius, Kristoffer; Kyhle, Kicki; Broman, Jan-Erik; Gordh, Torsten; Fredrikson, Mats
Cognitive behavioral therapy produces significant and long-lasting improvement for individuals with insomnia, but treatment resources are scarce. A "stepped care" approach has therefore been proposed, but knowledge is limited on how to best allocate patients to different treatment steps. In this study, 66 primary-care patients with insomnia attended a low-end treatment step: manual-guided cognitive behavioral therapy (CBT) for insomnia delivered by ordinary primary-care personnel. Based on clinically significant treatment effects, subjects were grouped into treatment responders or nonresponders. Baseline data were analyzed to identify predictors for treatment success. Long total sleep time at baseline assessment was the only statistically significant predictor for becoming a responder, and sleep time may thus be important to consider before enrolling patients in low-end treatments.
Brooke N Gentle
Full Text Available Research suggests that near ovulation women tend to consume fewer calories and engage in more physical activity; they are judged to be more attractive, express greater preferences for masculine and symmetrical men, and experience increases in sexual desire for men other than their primary partners. Some of these cycle phase shifts are moderated by partner attractiveness and interpreted as strategic responses to women's current reproductive context. The present study investigated changes in sleep across the ovulatory cycle, based on the hypothesis that changes in sleep may reflect ancestral strategic shifts of time and energy toward reproductive activities. Participants completed a 32-day daily diary in which they recorded their sleep time and quality for each day, yielding over 1,000 observations of sleep time and quality. Results indicated that, when the probability of conception was high, women partnered with less attractive men slept more, while women with more attractive partners slept less.
Satterfield, Brieann C; Hinson, John M; Whitney, Paul; Schmidt, Michelle A; Wisor, Jonathan P; Van Dongen, Hans P A
Adaptive decision making is profoundly impaired by total sleep deprivation (TSD). This suggests that TSD impacts fronto-striatal pathways involved in cognitive control, where dopamine is a key neuromodulator. In the prefrontal cortex (PFC), dopamine is catabolized by the enzyme catechol-O-methyltransferase (COMT). A functional polymorphism (Val158Met) influences COMT's enzymatic activity, resulting in markedly different levels of prefrontal dopamine. We investigated the effect of this polymorphism on adaptive decision making during TSD. Sixty-six healthy young adults participated in one of two in-laboratory studies. After a baseline day, subjects were randomized to either a TSD group (n = 32) with 38 h or 62 h of extended wakefulness or a well-rested control group (n = 34) with 10 h nighttime sleep opportunities. Subjects performed a go/no-go reversal learning (GNGr) task at well-rested baseline and again during TSD or equivalent control. During the task, subjects were required to learn stimulus-response relationships from accuracy feedback. The stimulus-response relationships were reversed halfway through the task, which required subjects to learn the new stimulus-response relationships from accuracy feedback. Performance on the GNGr task was quantified by discriminability (d') between go and no-go stimuli before and after the stimulus-response reversal. GNGr performance did not differ between COMT genotypes when subjects were well-rested. However, TSD exposed a significant vulnerability to adaptive decision making impairment in subjects with the Val allele. Our results indicate that sleep deprivation degrades cognitive control through a fronto-striatal, dopaminergic mechanism. Copyright © 2017 Elsevier Ltd. All rights reserved.
Carissimi, Alicia; Dresch, Fabiane; Martins, Alessandra Castro; Levandovski, Rosa Maria; Adan, Ana; Natale, Vincenzo; Martoni, Monica; Hidalgo, Maria Paz
This epidemiological study evaluated the impact of school time on sleep parameters of children and adolescents. This cross-sectional study involved 639 elementary and high school students (mean age 13.03 years, range 8-18, 58.5% female) from the south of Brazil. Participants answered the Morningness-Eveningness Questionnaire (MEQ), and were asked about their sleeping habits on weekdays and weekends. Sleep deficit was defined as the difference between sleep duration on weekdays and weekends. The morning-school-time students presented significantly higher age, bedtime and wake up differences, sleep deficits, and social jetlag. The sleep deficit presented by girls was greater than that observed in boys of the same age. The difference between weekday and weekend waking times was also significantly greater in girls than in boys aged 13-18 years. Sleep deficit was significantly positively correlated with age and differences in wake up times, and significantly negatively correlated with MEQ scores, social jetlag, difference between weekday and weekend bedtimes, midpoint of sleep on weekends, and midpoint of sleep on weekends corrected for sleep deficit. A step-by-step multivariate logistic regression identified social jetlag, the difference between waking times on weekdays and weekends, and the midpoint of sleep on weekends as significant predictors of sleep deficit (Adjusted R(2) = 0.95; F = 1606.87; p school time influences the sleep parameters. The association of school schedules and physiological factors influence the sleep/wake cycle. Copyright © 2015 Elsevier B.V. All rights reserved.
Phillips, Andrew J K; Clerx, William M; O'Brien, Conor S; Sano, Akane; Barger, Laura K; Picard, Rosalind W; Lockley, Steven W; Klerman, Elizabeth B; Czeisler, Charles A
The association of irregular sleep schedules with circadian timing and academic performance has not been systematically examined. We studied 61 undergraduates for 30 days using sleep diaries, and quantified sleep regularity using a novel metric, the sleep regularity index (SRI). In the most and least regular quintiles, circadian phase and light exposure were assessed using salivary dim-light melatonin onset (DLMO) and wrist-worn photometry, respectively. DLMO occurred later (00:08 ± 1:54 vs. 21:32 ± 1:48; p sleep propensity rhythm peaked later (06:33 ± 0:19 vs. 04:45 ± 0:11; p academic performance and SRI was observed. These findings show that irregular sleep and light exposure patterns in college students are associated with delayed circadian rhythms and lower academic performance. Moreover, the modeling results reveal that light-based interventions may be therapeutically effective in improving sleep regularity in this population.
Lin, Yingyi; Tremblay, Mark S; Katzmarzyk, Peter T; Fogelholm, Mikael; Hu, Gang; Lambert, Estelle V; Maher, Carol; Maia, Jose; Olds, Timothy; Sarmiento, Olga L; Standage, Martyn; Tudor-Locke, Catrine; Chaput, Jean-Philippe
The purpose of this multinational and cross-sectional study was to investigate whether nighttime sleep duration was associated with physical activity (PA) and sedentary time (SED) the following day, whether daytime PA/SED were associated with sleep duration the subsequent night, and whether the associations were modified by sex and study sites. Data from 5779 children aged 9-11years were analyzed. A waist-worn Actigraph GT3X+ accelerometer was used to assess children's 24-h movement behaviours for 7days, i.e. sleep duration, total SED, light-intensity physical activity (LPA), and moderate- to vigorous-intensity physical activity (MVPA). Multilevel linear regression models were used to account for the repeated measures nested within participants (there were up to 7 sleep→PA/SED and PA/SED→sleep pairings per participant) and schools, and adjusted for covariates. To facilitate interpretation, all sleep and PA/SED variables were standardized. Results showed that the relationship between sleep and PA/SED is bi-directional in this international sample of children. Specifically, for each one standard deviation (SD) unit increase in sleep duration, SED the following day decreased by 0.04 SD units, while LPA and MVPA increased by 0.04 and 0.02 SD units, respectively. Sleep duration decreased by 0.02 SD units and increased by 0.04 SD units for each one SD unit increase in SED and MVPA, respectively. Sleep duration was not affected by changes in LPA. These associations differed across sex and study sites in both directions. However, since the observed effect sizes are subtle, public health initiatives should consider the clinical and practical relevance of these findings. Copyright © 2017 Elsevier Inc. All rights reserved.
Chang, Hung-Ming; Chen, Bo-Jung; Wu, Un-In; Huang, Yi-Lun; Mai, Fu-Der
Sleep disorder is associated with metabolic disturbances, which was related to oxidative stress and subsequently sodium overload. Since liver plays important roles in metabolic regulation, present study is aimed to determine whether hepatic sodium, together with oxidative stress, would significantly alter after total sleep deprivation (TSD). Sodium ion was investigated by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Parameter for oxidative stress was examined by heat shock protein-25 (HSP-25) immunohistochemistry. TOF-SIMS spectrum indicated that hepatic Na +/K + ratio counting as 82.41 ± 9.5 was obtained in normal rats. Sodium ions were distributed in hepatocytes with several aggregations. However, following TSD, the intensity for Na +/K + ratio was relatively increased (101.94 ± 6.9) and signals for sodium image were strongly expressed throughout hepatocytes without spatial localization. Quantitative analysis revealed that HSP-25 staining intensity is 1.78 ± 0.27 in TSD rats, which was significantly higher than that of normal ones (0.68 ± 0.15). HSP-25 augmentation suggests that hepatocytes suffer from oxidative stress following TSD. Concerning oxidative stress induced sodium overload would impair metabolic function; enhanced hepatic sodium expression after TSD may be a major cause of TSD relevant metabolic diseases.
Mai, Fu-Der; Chen, Bo-Jung; Ling, Yong-Chien; Wu, Un-In; Huang, Yi-Lun; Chang, Hung-Ming
Area postrema (AP) is a circumventricular organ plays an important role in sodium homeostasis and cardiovascular regulation. Since sleep deficiency will cause cardiovascular dysfunction, the present study aims to determine whether sodium level would significantly alter in AP following total sleep deprivation (TSD). Sodium level was investigated in vivo by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Clinical manifestation of cardiovascular function was demonstrated by mean arterial pressure (MAP) values. Results indicated that in normal rats, TOF-SIMS spectrum revealed a major peak of sodium ion counting as 5.61 × 10 5 at m/ z 23. The sodium ions were homogeneous distributed in AP without specific localization. However, following TSD, the sodium intensity was relatively increased (6.73 × 10 5) and the signal for sodium image was strongly expressed throughout AP with definite spatial distribution. MAP of TSD rats is 138 ± 5 mmHg, which is significantly higher than that of normal ones (121 ± 3 mmHg). Regarding AP is an important area for sodium sensation and development of hypernatremic related sympatho-excitation; up-regulation of sodium expression following TSD suggests that high sodium level might over-activate AP, through complex neuronal networks involving in sympathetic regulation, which could lead to the formation of TSD relevant cardiovascular diseases.
Eliasson, Arne H; Eliasson, Arn H; Lettieri, Christopher J
To inform the design of a sleep improvement program for college students, we assessed academic performance, sleep habits, study hours, and extracurricular time, hypothesizing that there would be differences between US-born and foreign-born students. Questionnaires queried participants on bedtimes, wake times, nap frequency, differences in weekday and weekend sleep habits, study hours, grade point average, time spent at paid employment, and other extracurricular activities. Comparisons were made using chi square tests for categorical data and t tests for continuous data between US-born and foreign-born students. Of 120 participants (55 % women) with racial diversity (49 whites, 18 blacks, 26 Hispanics, 14 Asians, and 13 other), 49 (41 %) were foreign-born. Comparisons between US-born and foreign-born students showed no differences in average age or gender though US-born had more whites. There were no differences between US-born and foreign-born students for grade point averages, weekday bedtimes, wake times, or total sleep times. However, US-born students averaged 50 min less study time per day (p = 0.01), had almost 9 h less paid employment per week (14.5 vs 23.4 h per week, p = 0.001), and stayed up to socialize more frequently (63 vs 43 %, p = 0.03). Foreign-born students awakened an hour earlier and averaged 40 min less sleep per night on weekends. Cultural differences among college students have a profound effect on sleep habits, study hours, and extracurricular time. The design of a sleep improvement program targeting a population with diverse cultural backgrounds must factor in such behavioral variations in order to have relevance and impact.
Stephanie J Crowley
Full Text Available The aim of this descriptive analysis was to examine sleep timing, circadian phase, and phase angle of entrainment across adolescence in a longitudinal study design. Ninety-four adolescents participated; 38 (21 boys were 9-10 years ("younger cohort" and 56 (30 boys were 15-16 years ("older cohort" at the baseline assessment. Participants completed a baseline and then follow-up assessments approximately every six months for 2.5 years. At each assessment, participants wore a wrist actigraph for at least one week at home to measure self-selected sleep timing before salivary dim light melatonin onset (DLMO phase - a marker of the circadian timing system - was measured in the laboratory. Weekday and weekend sleep onset and offset and weekend-weekday differences were derived from actigraphy. Phase angles were the time durations from DLMO to weekday sleep onset and offset times. Each cohort showed later sleep onset (weekend and weekday, later weekend sleep offset, and later DLMO with age. Weekday sleep offset shifted earlier with age in the younger cohort and later in the older cohort after age 17. Weekend-weekday sleep offset differences increased with age in the younger cohort and decreased in the older cohort after age 17. DLMO to sleep offset phase angle narrowed with age in the younger cohort and became broader in the older cohort. The older cohort had a wider sleep onset phase angle compared to the younger cohort; however, an age-related phase angle increase was seen in the younger cohort only. Individual differences were seen in these developmental trajectories. This descriptive study indicated that circadian phase and self-selected sleep delayed across adolescence, though school-day sleep offset advanced until no longer in high school, whereupon offset was later. Phase angle changes are described as an interaction of developmental changes in sleep regulation interacting with psychosocial factors (e.g., bedtime autonomy.
Basner, Mathias; Mollicone, Daniel; Dinges, David F.
The Psychomotor Vigilance Test (PVT) objectively assesses fatigue-related changes in alertness associated with sleep loss, extended wakefulness, circadian misalignment, and time on task. The standard 10-min PVT is often considered impractical in applied contexts. To address this limitation, we developed a modified brief 3-min version of the PVT (PVT-B). The PVT-B was validated in controlled laboratory studies with 74 healthy subjects (34 female, aged 22-45 years) that participated either in a total sleep deprivation (TSD) study involving 33 h awake ( N=31 subjects) or in a partial sleep deprivation (PSD) protocol involving 5 consecutive nights of 4 h time in bed ( N=43 subjects). PVT and PVT-B were performed regularly during wakefulness. Effect sizes of 5 key PVT outcomes were larger for TSD than PSD and larger for PVT than for PVT-B for all outcomes. Effect size was largest for response speed (reciprocal response time) for both the PVT-B and the PVT in both TSD and PSD. According to Cohen's criteria, effect sizes for the PVT-B were still large (TSD) or medium to large (PSD, except for fastest 10% RT). Compared to the 70% decrease in test duration the 22.7% (range 6.9-67.8%) average decrease in effect size was deemed an acceptable trade-off between duration and sensitivity. Overall, PVT-B performance had faster response times, more false starts and fewer lapses than PVT performance (all psleep loss between PVT-B and PVT for all outcome variables (all P>0.15) but the fastest 10% response times during PSD ( P<0.001), and effect sizes increased from 1.38 to 1.49 (TSD) and 0.65 to 0.76 (PSD), respectively. In conclusion, PVT-B tracked standard 10-min PVT performance throughout both TSD and PSD, and yielded medium to large effect sizes. PVT-B may be a useful tool for assessing behavioral alertness in settings where the duration of the 10-min PVT is considered impractical, although further validation in applied settings is needed.
Basner, Mathias; Spaeth, Andrea M.; Dinges, David F.
Study Objectives: Chronic sleep restriction is prevalent in the U.S. population and associated with increased morbidity and mortality. The primary reasons for reduced sleep are unknown. Using population data on time use, we sought to identify individual characteristics and behaviors associated with short sleep that could be targeted for intervention programs. Design: Analysis of the American Time Use Survey (ATUS). Setting: Cross-sectional annual survey conducted by the U.S. Bureau of Labor Statistics. Participants: Representative cohort (N = 124,517) of Americans 15 years and older surveyed between 2003 and 2011. Interventions: None. Measurements and Results: Telephone survey of activities over 24 hours. Relative to all other waking activities, paid work time was the primary waking activity exchanged for sleep. Time spent traveling, which included commuting to/from work, and immediate pre- and post-sleep activities (socializing, grooming, watching TV) were also reciprocally related to sleep duration. With every hour that work or educational training started later in the morning, sleep time increased by approximately 20 minutes. Working multiple jobs was associated with the highest odds for sleeping ≤ 6 hours on weekdays (adjusted OR 1.61, 95% CI 1.44; 1.81). Self-employed respondents were less likely to be short sleepers compared to private sector employees (OR 0.83, 95% CI 0.72; 0.95). Sociodemographic characteristics associated with paid work (age 25-64, male sex, high income, and employment per se) were consistently associated with short sleep. Conclusions: U.S. population time use survey findings suggest that interventions to increase sleep time should concentrate on delaying the morning start time of work and educational activities (or making them more flexible), increasing sleep opportunities, and shortening morning and evening commute times. Reducing the need for multiple jobs may increase sleep time, but economic disincentives from working fewer hours
Hansen, Åse Marie; Gullander, Maria; Hogh, Annie; Persson, Roger; Kolstad, Henrik A; Willert, Morten Vejs; Bonde, Jens Peter; Kaerlev, Linda; Rugulies, Reiner; Grynderup, Matias Brødsgaard
Workplace bullying is a potent stressor that may increase sleep problems. Since physical fitness improves resilience to stress, it seems plausible that recreational physical activities may moderate the association between bullying and sleep. The study aimed to examine prospectively whether (i) bullying increases the risk of sleep problems, and (ii) the association between bullying and sleep problems is moderated by leisure-time physical activity (LTPA). The study sample comprised a cohort of public and private sector employees, who were enrolled into the Work Bullying and Harassment (WBH) cohort (N=3278) or the Psychosocial Risk Factors for Stress and Mental Disease (PRISME) cohort (N=4455). We measured workplace bullying using one question that was preceded by a definition of bullying. We used the Karolinska sleep questionnaire to assess sleep problems. The number of hours per week spent on LTPA estimated the degree of physical activity. Workplace bullying at baseline (T1) was associated with awakening problems and lack of restful sleep at follow-up (T2) but not with overall sleep problems and disturbed sleep. T1-LTPA did not moderate the association between T1-workplace bullying and T2-sleep problems. We found support that workplace bullying is related to development of T2-sleep problems, but this association seems not to be modified by LTPA.
Eugene, Andy R; Masiak, Jolanta
Sleep is an important component of human life, yet many people do not understand the relationship between the brain and the process of sleeping. Sleep has been proven to improve memory recall, regulate metabolism, and reduce mental fatigue. A minimum of 7 hours of daily sleep seems to be necessary for proper cognitive and behavioral function. The emotional and mental handicaps associated with chronic sleep loss as well as the highly hazardous situations which can be contributed to the lack of sleep is a serious concern that people need to be aware of. When one sleeps, the brain reorganizes and recharges itself, and removes toxic waste byproducts which have accumulated throughout the day. This evidence demonstrates that sleeping can clear the brain and help maintain its normal functioning. Multiple studies have been done to determine the effects of total sleep deprivation; more recently some have been conducted to show the effects of sleep restriction, which is a much more common occurrence, have the same effects as total sleep deprivation. Each phase of the sleep cycle restores and rejuvenates the brain for optimal function. When sleep is deprived, the active process of the glymphatic system does not have time to perform that function, so toxins can build up, and the effects will become apparent in cognitive abilities, behavior, and judgment. As a background for this paper we have reviewed literature and research of sleep phases, effects of sleep deprivation, and the glymphatic system of the brain and its restorative effect during the sleep cycle.
Arnold, Lesley M; Emir, Birol; Pauer, Lynne; Resnick, Malca; Clair, Andrew
To determine the time to immediate and sustained clinical improvement in pain and sleep quality with pregabalin in patients with fibromyalgia. A post hoc analysis of four 8- to 14-week phase 2-3, placebo-controlled trials of fixed-dose pregabalin (150-600 mg/day) for fibromyalgia, comprising 12 pregabalin and four placebo treatment arms. A total of 2,747 patients with fibromyalgia, aged 18-82 years. Pain and sleep quality scores, recorded daily on 11-point numeric rating scales (NRSs), were analyzed to determine time to immediate improvement with pregabalin, defined as the first of ≥2 consecutive days when the mean NRS score was significantly lower for pregabalin vs placebo in those treatment arms with a significant improvement at endpoint, and time to sustained clinical improvement with pregabalin, defined as a ≥1-point reduction of the baseline NRS score of patient responders who had a ≥30% improvement on the pain NRS, sleep NRS, or Fibromyalgia Impact Questionnaire (FIQ) from baseline to endpoint, or who reported "much improved" or "very much improved" on the Patient Global Impression of Change (PGIC) at endpoint. Significant improvements in pain and sleep quality scores at endpoint vs placebo were seen in 8/12 and 11/12 pregabalin treatment arms, respectively (P < 0.05). In these arms, time to immediate improvements in pain or sleep occurred by day 1 or 2. Time to sustained clinical improvement occurred significantly earlier in pain, sleep, PGIC, and FIQ responders (P < 0.02) with pregabalin vs placebo. Both immediate and sustained clinical improvements in pain and sleep quality occurred faster with pregabalin vs placebo. Wiley Periodicals, Inc.
Twenge, Jean M; Krizan, Zlatan; Hisler, Garrett
Insufficient sleep among adolescents carries significant health risks, making it important to determine social factors that change sleep duration. We sought to determine whether the self-reported sleep duration of U.S. adolescents changed between 2009 and 2015 and examine whether new media screen time (relative to other factors) might be responsible for changes in sleep. We drew from yearly, nationally representative surveys of sleep duration and time use among adolescents conducted since 1991 (Monitoring the Future) and 2007 (Youth Risk Behavior Surveillance System of the Centers for Disease Control; total N = 369,595). Compared to 2009, adolescents in 2015 were 16%-17% more likely to report sleeping less than 7 h a night on most nights, with an increase in short sleep duration after 2011-2013. New media screen time (electronic device use, social media, and reading news online) increased over this time period and was associated with increased odds of short sleep duration, with a clear exposure-response relationship for electronic devices after 2 or more hours of use per day. Other activities associated with short sleep duration, such as homework time, working for pay, and TV watching, were relatively stable or reduced over this time period, making it unlikely that these activities caused the sudden increase in short sleep duration. Increased new media screen time may be involved in the recent increases (from 35% to 41% and from 37% to 43%) in short sleep among adolescents. Public health interventions should consider electronic device use as a target of intervention to improve adolescent health. Copyright © 2017 Elsevier B.V. All rights reserved.
Murthy, C L Srinivasa; Bharti, Bhavneet; Malhi, Prahbhjot; Khadwal, Alka
To describe the sleep patterns and problems in children aged between 12 and 36 mo of age. This cross sectional survey was collected over a span of 1 y in Advanced Pediatric Centre, PGIMER, Chandigarh and crèches of Chandigarh. Children in the age group of 12 to 36 mo were included in study. Children with chronic illness, developmental delay, seizure disorder and lack of consent were excluded. A total of 368 children were enrolled. Main outcome measures were sleep duration over 1 to 3 y of life; sleep behavior at onset, during and waking of sleep and parent reported sleep problems and their predictors. The average duration of sleep was 12.5 h (S.D = 1.9). The mean total sleep duration and mean day time sleep duration decreased, while mean night time sleep increased as the age advanced from 12 to 36 mo. Following were the frequency of sleep habits seen in the index study; bed time routine was seen only in 68(18.5 %), a regular bed time ritual was seen in 281(76.4 %), 329(89.4 %) children frequently required 0-20 min time to fall asleep, 11(3 %) parents used sleep inducing drugs. Night waking (1 to 3 times a night) was seen in 297(80.7 %) and its frequency declined with age. Parent reported sleep problems were seen in 12.8 % (47/368). Lack of co-sleeping and night waking were considered as strongest predictors of parent reported sleep problems. Toddlers' sleep duration, night waking behavior, and day time naps decrease as the age progress while night time sleep duration increases with age. Lack of co-sleeping and night waking are considered as strongest predictors of parent reported sleep problems.
Wolfson, Amy R; Spaulding, Noah L; Dandrow, Craig; Baroni, Elizabeth M
With the onset of adolescence, teenagers require 9.2 hr of sleep and experience a delay in the timing of sleep. In the "real world" with early school start times, however, they report less sleep, striking differences between their school-weekend sleep schedules, and significant daytime sleepiness. Prior studies demonstrated that high schoolers with later school starts do not further delay bedtime but obtain more sleep due to later wake times. This study examined sleep-wake patterns of young adolescents attending urban, public middle schools with early (7:15 a.m.) versus late (8:37 a.m.) start times. Students (N = 205) were assessed at 2 time periods. Students at the late-starting school reported waking up over 1 hr later on school mornings and obtaining 50 min more sleep each night, less sleepiness, and fewer tardies than students at the early school. All students reported similar school-night bedtime, sleep hygiene practices, and weekend sleep schedules.
and van der Molen , M. W. Sleep deprivation influences some but not all processes of supervisory attention. Psychol. Sci., 2003, 14: 473–479. Kelly...and psychiatric disor- ders participated in this study after providing written informed consent. All subjects reported habitually obtaining 7–9 h of...characterizing brain areas using fMRI activation during parametric variations of attentional load.Neuron, 2001, 32: 737–745. Doran, S. M., Van Dongen
Basner, Mathias; Spaeth, Andrea M; Dinges, David F
Chronic sleep restriction is prevalent in the U.S. population and associated with increased morbidity and mortality. The primary reasons for reduced sleep are unknown. Using population data on time use, we sought to identify individual characteristics and behaviors associated with short sleep that could be targeted for intervention programs. Analysis of the American Time Use Survey (ATUS). Cross-sectional annual survey conducted by the U.S. Bureau of Labor Statistics. Representative cohort (N = 124,517) of Americans 15 years and older surveyed between 2003 and 2011. None. Telephone survey of activities over 24 hours. Relative to all other waking activities, paid work time was the primary waking activity exchanged for sleep. Time spent traveling, which included commuting to/ from work, and immediate pre- and post-sleep activities (socializing, grooming, watching TV) were also reciprocally related to sleep duration. With every hour that work or educational training started later in the morning, sleep time increased by approximately 20 minutes. Working multiple jobs was associated with the highest odds for sleeping ≤6 hours on weekdays (adjusted OR 1.61, 95% CI 1.44; 1.81). Self-employed respondents were less likely to be short sleepers compared to private sector employees (OR 0.83, 95% CI 0.72; 0.95). Sociodemographic characteristics associated with paid work (age 25-64, male sex, high income, and employment per se) were consistently associated with short sleep. U.S. population time use survey findings suggest that interventions to increase sleep time should concentrate on delaying the morning start time of work and educational activities (or making them more flexible), increasing sleep opportunities, and shortening morning and evening commute times. Reducing the need for multiple jobs may increase sleep time, but economic disincentives from working fewer hours will need to be offset. Raising awareness of the importance of sufficient sleep for health and safety may
Naqvi, Syed Y; Rabiei, Amin H; Maltenfort, Mitchell G; Restrepo, Camilo; Viscusi, Eugene R; Parvizi, Javad; Rasouli, Mohammad R
This study aims to evaluate the effect of sleep apnea (SA) on perioperative complications after total joint arthroplasty (TJA) and whether the type of anesthesia influences these complications. Using the ninth and tenth revisions of the International Classification of Diseases, coding systems, we queried our institutional TJA database from January 2005 to June 2016 to identify patients with SA who underwent TJA. These patients were matched in a 1:3 ratio based on age, gender, type of surgery, and comorbidities to patients who underwent TJA but were not coded for SA. Perioperative complications were identified using the same coding systems. Multivariate analysis was used to test if SA is an independent predictor of perioperative complications and if type of anesthesia can affect these complications. A total of 1246 patients with SA were matched to 3738 patients without SA. Pulmonary complications occurred more frequently in patients with SA (1.7% vs 0.6%; P system complications and mortality (odds ratio = 15.88; 95% confidence interval, 3.93-64.07; P gastrointestinal complications, acute anemia, and mortality were lower in SA patients when regional anesthesia was used (P < .05). SA increases risk of postoperative pulmonary complications. The use of regional anesthesia may reduce risk of pulmonary complications and mortality in SA patients undergoing TJA. Copyright © 2017 Elsevier Inc. All rights reserved.
Cox, R.; Tijdens, R.R.; Meeter, M.; Sweegers, C.M.; Talamini, L.M.
Contextual cues are known to benefit memory retrieval, but whether and how sleep affects this context effect remains unresolved. We manipulated contextual congruence during memory retrieval in human volunteers across 12 h and 24 h intervals beginning with either sleep or wakefulness. Our data
Yland, Jennifer; Guan, Stanford; Emanuele, Erin; Hale, Lauren
Insufficient sleep among school-aged children is a growing concern, as numerous studies have shown that chronic short sleep duration increases the risk of poor academic performance and specific adverse health outcomes. We examined the association between weekday nighttime sleep duration and 3 types of screen exposure: television, computer use, and video gaming. We used age 9 data from an ethnically diverse national birth cohort study, the Fragile Families and Child Wellbeing Study, to assess the association between screen time and sleep duration among 9-year-olds, using screen time data reported by both the child (n = 3269) and by the child's primary caregiver (n= 2770). Within the child-reported models, children who watched more than 2 hours of television per day had shorter sleep duration by approximately 11 minutes per night compared to those who watched less than 2 hours of television (β = -0.18; P computer use were associated with reduced sleep duration. For both child- and parent-reported screen time measures, we did not find statistically significant differences in effect size across various types of screen time. Screen time from televisions and computers is associated with reduced sleep duration among 9-year-olds, using 2 sources of estimates of screen time exposure (child and parent reports). No specific type or use of screen time resulted in significantly shorter sleep duration than another, suggesting that caution should be advised against excessive use of all screens.
Adelantado-Renau, Mireia; Diez-Fernandez, Ana; Beltran-Valls, Maria Reyes; Soriano-Maldonado, Alberto; Moliner-Urdiales, Diego
The aims of the present study were to analyze the association of sleep patterns with academic and cognitive performance in adolescents, and to test the potential mediating effect of different activities of screen media usage on this association. A sample of 269 adolescents (140 boys) aged 14 years from the baseline data of the Deporte, ADOlescencia y Salud study completed questionnaires about sleep quality, cognitive performance, and leisure-time sedentary behaviors. Sleep duration was objectively computed using a wrist-worn GENEActiv accelerometer and academic performance was analyzed through school records. Sleep quality (but not sleep duration) was associated with all the academic performance indicators (all p<0.05). Analysis of covariance revealed higher grades among adolescents with better sleep quality (PSQI≤5; all p<0.05). These analyses showed no differences regarding cognitive performance. Internet use time was revealed as a mediator of the association between sleep quality and academic performance, being significant for all academic performance indicators (P M ranging from 15.5% to 16.0%). The association between sleep quality and academic performance in adolescents is mediated by time of Internet use. Overall, reducing Internet use in adolescents could be an achievable intervention for improving sleep quality, with potentially positive effects on academic performance. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.
Hansen, Åse Marie; Gullander, Maria; Hogh, Annie
and Harassment (WBH) cohort (N=3278) or the Psychosocial Risk Factors for Stress and Mental Disease (PRISME) cohort (N=4455). We measured workplace bullying using one question that was preceded by a definition of bullying. We used the Karolinska sleep questionnaire to assess sleep problems. The number of hours......OBJECTIVES: Workplace bullying is a potent stressor that may increase sleep problems. Since physical fitness improves resilience to stress, it seems plausible that recreational physical activities may moderate the association between bullying and sleep. The study aimed to examine prospectively...... whether (i) bullying increases the risk of sleep problems, and (ii) the association between bullying and sleep problems is moderated by leisure-time physical activity (LTPA). METHODS: The study sample comprised a cohort of public and private sector employees, who were enrolled into the Work Bullying...
Arbind Kumar Choudhary
Full Text Available Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300 and reaction time [visual (VRT and auditory (ART] among night watchmen, at subsequent; first (1st day, fourth (4th day and seventh (7th day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18–35 years (n=50 after providing written informed consent and divided into two group. Group I-(Normal sleep (n=28 working in day time and used to have normal sleep in night (≥8 h; Group II-(Restricted sleep (n=22 - working in night time and used to have less sleep in night (≤3 h. Statistical significance between the different groups was determined by the independent student ʻtʼ test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSSscore, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.
Choudhary, Arbind Kumar; Kishanrao, Sadawarte Sahebrao; Dadarao Dhanvijay, Anup Kumar; Alam, Tanwir
Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300) and reaction time [visual (VRT) and auditory (ART)] among night watchmen, at subsequent; first (1st) day, fourth (4th) day and seventh (7th) day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18-35 years) (n=50) after providing written informed consent and divided into two group. Group I-(Normal sleep) (n=28) working in day time and used to have normal sleep in night (≥8 h); Group II-(Restricted sleep) (n=22) - working in night time and used to have less sleep in night (≤3 h). Statistical significance between the different groups was determined by the independent student ' t ' test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS) score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSS)score, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.
Ferguson, Sally A; Paech, Gemma M; Dorrian, Jillian; Roach, Gregory D; Jay, Sarah M
The purpose of the current study was to investigate the impact of work- and sleep-related factors on an objective measure of response time in a field setting. Thirty-five mining operators working 12-h shift patterns completed daily sleep and work diaries, wore activity monitors continuously and completed palm-based psychomotor vigilance tests (palmPVT) at the start and end of each shift. Linear mixed models were used to test the main effects on response time of roster, timing of test, sleep history and prior wake. The time at which the test occurred was a significant predictor of response time (F₃(,)₄₀₃(.)₄ = 6.72, p times than the start of night shifts, and the start or end of day shifts. Further, the amount of sleep obtained in the 24h prior to the test was also a significant predictor of response time (F₃(,)₄₀₇(.)₀ = 3.05, p time indicative of performance impairments. Of more interest however is that immediate sleep history was also predictive of changes in response time with lower amounts of prior sleep related to slower response times. The current data provides further evidence that sleep is a primary mediator of performance, independent of roster pattern. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Owens, Judith A; Belon, Katherine; Moss, Patricia
To examine the impact of a 30-minute delay in school start time on adolescents' sleep, mood, and behavior. Participants completed the online retrospective Sleep Habits Survey before and after a change in school start time. An independent high school in Rhode Island. Students (n = 201) in grades 9 through 12. Intervention Institution of a delay in school start time from 8 to 8:30 am. Sleep patterns and behavior, daytime sleepiness, mood, data from the Health Center, and absences/tardies. After the start time delay, mean school night sleep duration increased by 45 minutes, and average bedtime advanced by 18 minutes (95% confidence interval, 7-29 minutes [t(423) = 3.36; P students getting less than 7 hours of sleep decreased by 79.4%, and those reporting at least 8 hours of sleep increased from 16.4% to 54.7%. Students reported significantly more satisfaction with sleep and experienced improved motivation. Daytime sleepiness, fatigue, and depressed mood were all reduced. Most health-related variables, including Health Center visits for fatigue-related complaints, and class attendance also improved. A modest delay in school start time was associated with significant improvements in measures of adolescent alertness, mood, and health. The results of this study support the potential benefits of adjusting school schedules to adolescents' sleep needs, circadian rhythm, and developmental stage.
Saito, Luis P; Fukushiro, Daniela F; Hollais, André W; Mári-Kawamoto, Elisa; Costa, Jacqueline M; Berro, Laís F; Aramini, Tatiana C F; Wuo-Silva, Raphael; Andersen, Monica L; Tufik, Sergio; Frussa-Filho, Roberto
It has been demonstrated that a prolonged period (48 h) of paradoxical sleep deprivation (PSD) potentiates amphetamine (AMP)-induced behavioral sensitization, an animal model of addiction-related neuroadaptations. In the present study, we examined the effects of an acute short-term deprivation of total sleep (TSD) (6h) on AMP-induced behavioral sensitization in mice and compared them to the effects of short-term PSD (6 h). Three-month-old male C57BL/6J mice underwent TSD (experiment 1-gentle handling method) or PSD (experiment 2-multiple platforms method) for 6 h. Immediately after the sleep deprivation period, mice were tested in the open field for 10 min under the effects of saline or 2.0 mg/kg AMP. Seven days later, to assess behavioral sensitization, all of the mice received a challenge injection of 2.0 mg/kg AMP and were tested in the open field for 10 min. Total, peripheral, and central locomotion, and grooming duration were measured. TSD, but not PSD, potentiated the hyperlocomotion induced by an acute injection of AMP and this effect was due to an increased locomotion in the central squares of the apparatus. Similarly, TSD facilitated the development of AMP-induced sensitization, but only in the central locomotion parameter. The data indicate that an acute period of TSD may exacerbate the behavioral effects of AMP in mice. Because sleep architecture is composed of paradoxical and slow wave sleep, and 6-h PSD had no effects on AMP-induced hyperlocomotion or sensitization, our data suggest that the deprivation of slow wave sleep plays a critical role in the mechanisms that underlie the potentiating effects of TSD on both the acute and sensitized addiction-related responses to AMP. Copyright © 2013 Elsevier Inc. All rights reserved.
Owens, Judith A; Dearth-Wesley, Tracy; Herman, Allison N; Oakes, J Michael; Whitaker, Robert C
To determine whether simultaneous school start time changes (delay for some schools; advance for others) impact adolescents' sleep. Quasi-experimental study using cross-sectional surveys before and after changes to school start times in September 2015. Eight middle (grades 7-8), 3 secondary (grades 7-12), and 8 high (grades 9-12) schools in Fairfax County (Virginia) public schools. A total of 2017 (6% of ~34,900) students were surveyed before start time changes, and 1180 (3% of ~35,300) were surveyed after. A 50-minute delay (7:20 to 8:10 am) in start time for high schools and secondary schools and a 30-minute advance (8:00 to 7:30 am) for middle schools. Differences before and after start time changes in self-reported sleep duration and daytime sleepiness. Among respondents, 57.5% were non-Hispanic white, and 10.3% received free or reduced-priced school meals. Before start time changes, high/secondary and middle school students slept a mean (SD) of 7.4 (1.2) and 8.4 (1.0) hours on school nights, respectively, and had a prevalence of daytime sleepiness of 78.4% and 57.2%, respectively. Adjusted for potential confounders, students with a 50-minute delay slept 30.1 minutes longer (95% confidence interval [CI], 24.3-36.0) on school nights and had less daytime sleepiness (-4.8%; 95% CI, -8.5% to -1.1%), whereas students with a 30-minute advance slept 14.8 minutes less (95% CI, -21.6 to -8.0) and had more daytime sleepiness (8.0%; 95% CI, 2.5%-13.5%). Both advances and delays in school start times are associated with changes in adolescents' school-night sleep duration and daytime sleepiness. Larger changes might occur with later start times. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.
Gamble, Karen L; May, Roberta S; Besing, Rachel C; Tankersly, Amelia P; Fargason, Rachel E
Patients with attention-deficit/hyperactivity disorder (ADHD) often exhibit disrupted sleep and circadian rhythms. Determination of whether sleep disturbance and/or circadian disruption are differentially associated with symptom severity is necessary to guide development of future treatment strategies. Therefore, we measured sleep and ADHD symptoms in participants aged 19-65 who met the DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision) criteria for ADHD and insomnia without psychiatric comorbidities by monitoring actigraphy and daily sleep logs for 2 wks, as well as the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), the ADHD Rating Scale (ADHD-RS), and a clinic-designed sleep behavior questionnaire. Principal components analysis identified correlated circadian- and sleep-related variables in all participants with ADHD who completed the study (n = 24). The identified components were entered into a backwards stepwise linear regression analysis, which indicated that delayed sleep timing and increased sleepiness (ESS) (but not sleep duration or sleep efficiency) significantly predicted greater severity of both hyperactive-impulsive and inattentive ADHD symptoms (p sleep quality (PSQI scores; p sleep" compared with 57.2% and 50% of inattentive and symptom-controlled participants, respectively (p sleep timing and daytime sleepiness, suggesting that treatment interventions aimed at advancing circadian phase may improve daytime sleepiness. In addition, ADHD adults with combined hyperactive-impulsive and inattentive symptoms have decreased sleep quality as well as the delayed sleep timing of predominately inattentive subtypes.
Boergers, Julie; Gable, Christopher J; Owens, Judith A
Chronic insufficient sleep is a growing concern among adolescents and is associated with a host of adverse health consequences. Early school start times may be an environmental contributor to this problem. The purpose of this study was to examine the impact of a delay in school start time on sleep patterns, sleepiness, mood, and health-related outcomes. Boarding students (n = 197, mean age = 15.6 yr) attending an independent high school completed the School Sleep Habits Survey before and after the school start time was experimentally delayed from 8:00 a.m. to 8:25 a.m. The delay in school start time was associated with a significant (29 min) increase in sleep duration on school nights. The percentage of students receiving 8 or more hours of sleep on a school night increased to more than double, from 18% to 44%. Students in 9th and 10th grade and those with lower baseline sleep amounts were more likely to report improvements in sleep duration after the schedule change. Daytime sleepiness, depressed mood, and caffeine use were all significantly reduced after the delay in school start time. Sleep duration reverted to baseline levels when the original (earlier) school start time was reinstituted. A modest (25 min) delay in school start time was associated with significant improvements in sleep duration, daytime sleepiness, mood, and caffeine use. These findings have important implications for public policy and add to research suggesting the health benefits of modifying school schedules to more closely align with adolescents' circadian rhythms and sleep needs.
Wheaton, Anne G.; Chapman, Daniel P.; Croft, Janet B.
Background: Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy…
Dewald, Julia F.; Short, Michelle A.; Gradisar, Michael; Oort, Frans J.; Meijer, Anne Marie
Although adolescents often experience insufficient and/or poor sleep, sleep variables such as total sleep time do not account for individuals' sleep need and sleep debt and may therefore be an inadequate representation of adolescents' sleep problems and its daytime consequences. This problem can be
Dewald, J.F.; Short, M.A.; Gradisar, M.; Oort, F.J.; Meijer, A.M.
Although adolescents often experience insufficient and/or poor sleep, sleep variables such as total sleep time do not account for individuals’ sleep need and sleep debt and may therefore be an inadequate representation of adolescents’ sleep problems and its daytime consequences. This problem can be
Allen, A J M Hirsch; Amram, Ofer; Tavakoli, Hamid; Almeida, Fernanda R; Hamoda, Mona; Ayas, Najib T
In the majority of people with obstructive sleep apnea, the disorder remains undiagnosed. This may be partly a result of inadequate access to diagnostic sleep services. We thus hypothesized that even modest travel times to a sleep clinic may delay diagnosis and reduce detection of milder disease. We sought to determine whether travel time between an individual's home and a sleep clinic is associated with sleep apnea severity at presentation. We recruited patients referred for suspected sleep apnea to the University of British Columbia Hospital Sleep Clinic between May 2003 and July 2011. The patient's place of residence was geocoded at the postal code level. Travel times between the population-weighted dissemination areas for each patient and the sleep clinic were calculated using ArcGIS (ESRI, Redlands, CA) network analyst and the Origin-Destination matrix function. All patients underwent full polysomnography. There were 1,275 patients; 69% were male, the mean age was 58 years. (SD = 11.9), and the mean apnea-hypopnea index was 22 per hour (SD = 21.6). In the univariate model, travel time was a significant predictor of obstructive sleep apnea severity (P = 0.02). After controlling for confounders including sex, age, obesity, and education, travel time remained a significant predictor of sleep apnea severity (P travel time was associated with an increase in the apnea-hypopnea index of 1.4 events per hour. For reasons that remain to be determined, travel times are associated with the severity of obstructive sleep apnea at presentation to a sleep clinic. If the results can be verified at other centers, this may help guide the geographic distribution of sleep centers within a health care system.
Liou, Yiing Mei; Liou, Tsan-Hon; Chang, Lu-Chuan
Over the past 30 years, the prevalence of overweight and obesity in children and adolescents has nearly tripled. Physical inactivity, unbalanced diet, and unhealthy lifestyles may cause lifelong obesity. A representative, national cross-sectional study was carried out between 2006 and 2007 with 40 middle high schools with 384 classes. We used a three-stage stratified systematic sampling design with a probability proportionate to the size from the northern, middle, southern, and eastern areas in Taiwan. Questionnaires were completed by 8640 students (51.7% boys and 48.3% girls) aged between 13 and 16 years. Obesity was identified in 7.2% of the participants and 16.1% were overweight. Using stepwise logistic regression, we found that those whose fathers or mothers were obese, watched television for more than 2 hours/day on weekdays and slept for less than 7.75 hours/day at weekends had a statistically significantly greater risk of obesity (females: ORs = 3.4, 4.2, 1.8, and 4.2, respectively; P leisure time and help them have sufficient sleep. Nurses can play a key role in health promotion in relation to childhood and adolescent obesity.
Takahashi, H; Masaki, C; Makino, M; Yoshida, M; Mukaibo, T; Kondo, Y; Nakamoto, T; Hosokawa, R
To treat sleep bruxism (SB), symptomatic therapy using stabilisation splints (SS) is frequently used. However, their effects on psychological stress and sleep quality have not yet been examined fully. The objective of this study was to clarify the effects of SS use on psychological stress and sleep quality. The subjects (11 men, 12 women) were healthy volunteers. A crossover design was used. Sleep measurements were performed for three consecutive days or longer without (baseline) or with an SS or palatal splint (PS), and data for the final day were evaluated. We measured masseter muscle activity during sleep using portable electromyography to evaluate SB. Furthermore, to compare psychological stress before and after sleep, assessments were made based on STAI-JYZ and the measurement of salivary chromogranin A. To compare each parameter among the three groups (baseline, SS and PS), Friedman's and Dunn's tests were used. From the results of the baseline measurements, eight subjects were identified as high group and 15 as low group. Among the high group, a marked decrease in the number of bruxism events per hour and an increase in the difference in the total STAI Y-1 scores were observed in the SS group compared with those at baseline (P sleep stages. SS use may be effective in reducing the number of SB events, while it may increase psychological stress levels, and SS use did not apparently influence sleep stages. © 2013 John Wiley & Sons Ltd.
de Aquino-Lemos, Valdir; Santos, Ronaldo Vagner T; Antunes, Hanna Karen Moreira; Lira, Fabio S; Luz Bittar, Irene G; Caris, Aline V; Tufik, Sergio; de Mello, Marco Tulio
This study aimed to assess the effect of two sessions of acute physical exercise at 50% VO2peak performed under hypoxia (equivalent to an altitude of 4500 m for 28 h) on sleep, mood and reaction time. Forty healthy men were randomized into 4 groups: Normoxia (NG) (n = 10); Hypoxia (HG) (n = 10); Exercise under Normoxia (ENG) (n = 10); and Exercise under Hypoxia (EHG) (n = 10). All mood and reaction time assessments were performed 40 min after awakening. Sleep was reassessed on the first day at 14 h after the initiation of hypoxia; mood and reaction time were measured 28 h later. Two sessions of acute physical exercise at 50% VO2peak were performed for 60 min on the first and second days after 3 and 27 h, respectively, after starting to hypoxia. Improved sleep efficiency, stage N3 and REM sleep and reduced wake after sleep onset were observed under hypoxia after acute physical exercise. Tension, anger, depressed mood, vigor and reaction time scores improved after exercise under hypoxia. We conclude that hypoxia impairs sleep, reaction time and mood. Acute physical exercise at 50% VO2peak under hypoxia improves sleep efficiency, reversing the aspects that had been adversely affected under hypoxia, possibly contributing to improved mood and reaction time.
Full Text Available The Munich Chronotype Questionnaire (MCTQ uses sleep behavior to assess chronotype, but the extent to which such sleep behavior based assessments might be useful in populations with sleep disorders, such as insomnia, is currently unclear. We thus systematically assessed sleep disorders, MCTQ and the Morningness-Eveningness Questionnaire (MEQ, another behavioral preferencebased assessment of chronotype, in 310 individuals. In a smaller substudy (n = 121, we compared the MCTQ to sleep diaries in insomnia patients and good sleepers. Insomnia patients had overall lower consistency in chronotypes compared to good sleepers on the MCTQ compared to the MEQ, which was also evident when compared to sleep diaries. As insomnia disorder is characterized by time gaps spent awake during the night due to difficulty maintaining sleep, there may be limitations in using mid-sleep time as an accurate indicator of chronotype in insomnia patients. Our study suggests that the MCTQ should be used in conjunction with another existing questionnaire or assessment tool when assessing chronotype in insomnia patients.
McClain, James J; Lewin, Daniel S; Laposky, Aaron D; Kahle, Lisa; Berrigan, David
To examine the associations between objectively measured physical activity (PA) or sedentary behavior and self-reported sleep duration or daytime sleepiness in a nationally representative sample of healthy US adults (N=2128). We report analyses of four aspects of sedentary behavior and PA derived from accelerometry data (minutes of sedentary time, activity counts/minute, Minutes of Moderate and Vigorous PA [MVPA], and MVPA in 10-minute bouts) versus self-report of sleep duration and frequency of daytime sleepiness from the 2005-2006 National Health and Nutrition Examination Survey. Age and sex dependence of associations between PA and sleep were observed. Aspects of PA were significantly lower in adults reporting more frequent daytime sleepiness in younger (20-39) and older (≥ 60) age groups, but not in middle-aged (40-59), respondents. In younger respondents, PA increased with sleep duration, but in middle aged and older respondents PA was either unrelated to sleep duration or lower in those reporting ≥ 8 h of sleep. Objectively measured sedentary time showed limited evidence of associations with sleep duration. Further research delineating the relationships between sleep and PA is important because both activities have been implicated in diverse health outcomes as well as in the etiology of obesity. Published by Elsevier Inc.
Tsai, Ling-Ling; Li, Sheng-Ping
In this study we evaluated the effect of a two-credit (100 min./week) "Sleep Management" course on the sleep patterns of college students as the course progressed over an 18-wk. semester. Curricular activity included lectures, group discussions, and practice of self-evaluation of sleep. Instead of giving the students the whole list of sleep hygiene at the outset of the course, each concept of sleep hygiene was introduced and discussed under related lecture topics. A total of 241 students (131 men and 110 women) took the course and kept 7-day sleep logs three times. Concurrently, sleep-log data were collected from 65 students (32 men and 33 women) who were not taking the course. Both groups showed similar varieties of academic backgrounds and characteristics of sleep patterns at the beginning. Similarly, their sleep patterns, namely, rise time, nighttime awakenings, time asleep, time in bed, sleep efficiency, and rise time regularity, changed over the semester. Women in both groups had more nighttime awakenings. In contrast, sleep quality was progressively better for the group in the course but not for the control group. Only women in the course decreased their nap time in the second and third months. Thus, the course of "Sleep Management" only had a mild and limited effect on sleep patterns. The course content needs refinement to maximize influence on students' sleep patterns and habits, particularly, on reduction of insufficient sleep and daytime sleepiness which are the highest ranking sleep problems among college students.
Depression due to long work hours and sleep deprivation is a major occupational health concern. The extent to which work hours and sleep are associated with depression was investigated in employees of small- and medium-scale businesses in the Japanese city of Yashio, Saitama, and in the Ohta ward of Tokyo, a suburb of Tokyo, controlling for various potential confounders. In this cross-sectional study, a total of 2,643 full-time employees (1,928 men and 715 women), aged 18-79 years (mean = 45 years), in 296 small- and medium-scale businesses were surveyed from August 2002 to December 2002 using a self-administered questionnaire evaluating work hours, sleep status, and covariates including sociodemographic and socioeconomic factors, health behaviors, biological factors, medication usage, and occupational factors. Depression was assessed using the Center for Epidemiologic Studies Depression Scale. Prevalence of depression by work hours, sleep status, and covariates was analyzed by χ² test. Risk of depression by work hours, sleep status, and both combined was estimated by multivariate logistic regression analysis. Participants working > 10 hours per day, sleeping hours per day, and reporting insufficient sleep were, respectively, 37%, 43%, and 97% more likely to be depressed than those working 6 to 8 hours per day, sleeping 6 to hours per day, and reporting sufficient sleep (P working > 10 hours per day or > 8 to 10 hours per day with hours per day of sleep showed a 41%-169% higher prevalence of depression versus those working 6 to 8 hours per day with 6+ hours per day of sleep (P work-hour categories (6 to 8, > 8 to 10, and > 10 hours per day) showed a 62%-179% increase in the prevalence of depression versus those working 6 to 8 hours per day and reporting sufficient sleep (P work-hour category with 6+ hours of sleep or with subjective sufficient sleep. Depression associated with long work hours is primarily a result of sleep deprivation. Greater attention should be
Cipolli, Carlo; Guazzelli, Mario; Bellucci, Claudia; Mazzetti, Michela; Palagini, Laura; Rosenlicht, Nicholas; Feinberg, Irwin
This study aimed to investigate the cycles (2nd/4th) and duration-related (5/10 min) variations in the story-like organization of dream experience elaborated during rapid eye movement (REM) sleep. Dream reports were analysed using story grammar rules. Reports were provided by those subjects (14 of 22) capable of reporting a dream after each of the four awakenings provoked in 2 consecutive nights during REM sleep of the 2nd and 4th cycles, after periods of either 5 or 10 min, counterbalanced across the nights. Two researchers who were blind as to the sleep condition scored the dream reports independently. The values of the indicators of report length (measured as value of total word count) and of story-like organization of dream reports were matched taking time-of-night (2nd and 4th cycles) and REM duration (5 versus 10 min) as factors. Two-way analyses of variance showed that report length increased significantly in 4th-cycle REM sleep and nearly significantly for longer REM duration, whereas the number of dream-stories per report did not vary. The indices of sequential (number of statements describing the event structure developed in the story) and hierarchical (number of episodes per story) organization increased significantly only in dream-stories reported after 10 min of 4th-cycle REM sleep. These findings indicate that the characteristics of structural organization of dream-stories vary along with time of night, and suggest that the elaboration of a long and complex dream-story requires a fairly long time and the availability of a great amount of cognitive resources to maintain its continuity and coherence. © 2014 European Sleep Research Society.
Christensen, Matthew A.; Bettencourt, Laura; Kaye, Leanne; Moturu, Sai T.; Nguyen, Kaylin T.; Olgin, Jeffrey E.; Pletcher, Mark J.; Marcus, Gregory M.
Background Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality. Aims The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep. Methods We performed a cross-sectio...
Bassi, Alejandro; Vivaldi, Ennio A.; Ocampo-Garcés, Adrián
Study Objectives: A model of rapid eye movement (REM) sleep expression is proposed that assumes underlying regulatory mechanisms operating as inhomogenous Poisson processes, the overt results of which are the transitions into and out of REM sleep. Design: Based on spontaneously occurring REM sleep episodes (“Episode”) and intervals without REM sleep (“Interval”), 3 variables are defined and evaluated over discrete 15-second epochs using a nonlinear logistic regression method: “Propensity” is the instantaneous rate of into-REM transition occurrence throughout an Interval, “Volatility” is the instantaneous rate of out-of-REM transition occurrence throughout an Episode, and “Opportunity” is the probability of being in non-REM (NREM) sleep at a given time throughout an Interval, a requisite for transition. Setting: 12:12 light:dark cycle, isolated boxes. Participants: Sixteen male Sprague-Dawley rats Interventions: None. Spontaneous sleep cycles. Measurements and Results: The highest levels of volatility and propensity occur, respectively, at the very beginning of Episodes and Intervals. The new condition stabilizes rapidly, and variables reach nadirs at minute 1.25 and 2.50, respectively. Afterward, volatility increases markedly, reaching values close to the initial level. Propensity increases moderately, the increment being stronger through NREM sleep bouts occurring at the end of long Intervals. Short-term homeostasis is evidenced by longer REM sleep episodes lowering propensity in the following Interval. Conclusions: The stabilization after transitions into Episodes or Intervals and the destabilization after remaining for some time in either condition may be described as resulting from continuous processes building up during Episodes and Intervals. These processes underlie the overt occurrence of transitions. Citation: Bassi A; Vivaldi EA; Ocampo-Garcées A. The time course of the probability of transition into and out of REM sleep. SLEEP 2009
Vanderwende, C; Spoerlein, M T; Lapollo, J
Cocaine in graded doses potentiated ketamine-induced loss of the righting reflex and sleeping time. Potentiation of drug-induced sleep with cocaine was not a generalized phenomenon inasmuch as it had no effect on sleep induced by pentobarbital or hexobarbital and decreased sleep induced by phenobarbital. Pentylenetetrazole reduced ketamine sleep but d-amphetamine had a potentiative action. dl-alpha-Methyl-p-tyrosine methyl ester itself increased both the number losing the righting reflex and the sleeping time induced by ketamine. However, the effect cocaine on sleeping time was blocked 3 h after the dl-alpha-methyl-p-tyrosine methyl ester was given. The alpha and beta adrenergic blocking drugs, phenoxybenzamine and propranolol, increased the number of animals losing the righting reflex with ketamine, and phenoxybenzamine lengthened the sleeping time. Alpha and beta adrenergic agonists, l-phenylephrine and isoproterenol, increased the number of animals going to sleep with ketamine but did not significantly alter how long they would sleep. The agonists had no effect on the cocaine interaction with ketamine, whereas the antagonists blocked the effect of cocaine. Both stimulation and blockade of dopamine receptors led to increased loss of the righting reflex and sleeping time with ketamine but only receptor blockade antagonized the effect of cocaine on ketamine-induced sleep. Thus, both the noradrenergic and dopaminergic systems appear to be involved in the ability of cocaine to potentiate ketamine-induced sleep.
Lauridsen, Mette Munk; Frøjk, Jesper; de Muckadell, Ove B Schaffalitzky; Vilstrup, Hendrik
The continuous reaction times (CRT) method describes arousal functions. Reaction time instability in a patient with liver disease indicates covert hepatic encephalopathy (cHE). The effects of sleep deprivation are unknown although cirrhosis patients frequently suffer from sleep disorders. The aim of this study was to determine if sleep deprivation influences the CRT test. Eighteen cirrhosis patients and 27 healthy persons were tested when rested and after one night's sleep deprivation. The patients filled out validated sleep quality questionnaires. Seven patients (38%) had unstable reaction times (a CRTindex sleep that was not related to their CRT tests before or after the sleep deprivation. In the healthy participants, the sleep deprivation slowed their reaction times by 11% (p sleep deprivation normalized or improved the reaction time stability of the patients with a CRTindex below 1.9 and had no effect in the patients with a CRTindex above 1.9. There was no relation between reported sleep quality and reaction time results. Thus, in cirrhosis patients, sleep disturbances do not lead to 'falsely' slowed and unstable reaction times. In contrast, the acute sleep deprivation slowed and destabilized the reaction times of the healthy participants. This may have negative consequences for decision-making.
Wang, X L; Wang, J; Mu, D L; Wang, D X
Objective: To investigate the effect of dexmedetomidine adding to ropivacaine for continuous femoral nerve block on the improvement of postoperative sleep quality in elderly patients after total knee arthroplasty. Methods: One hundred and sixty patients aged 60 years or older in Jishuitan Hospital scheduled for single total knee arthroplasty between Nov. 2016 and Jun. 2017 were recruited. All patients received spinal anesthesia and were randomized to receive either combined ropivacaine and dexmedetomidine (0.2% ropivacaine 250 ml and 5 μg/kg dexmedetomidine, at a rate of 5 ml/h or 0.1 μg·kg -1 ·h -1 dexmedetomidine, dexmedetomidine group) or only ropivacaine (0.2% ropivacaine, at a rate of 5 ml/h, controlled group) for continuous femoral nerve block as postoperative analgesia after surgery. The severity of postoperative pain was assessed with numeric rating scale at 4, 24, and 48 hours after surgery both at rest and with movement. Subjective sleep quality and delirium were evaluated daily during the first 3 days postoperatively. Results: The subjective sleep quality scores were 2(1-4), 2(1-4) and 4(2-8), 4(2-7) in dexmedetomidine group and controlled group respectively on the 1st and 2nd days after surgery. The scores of dexmedetomidine group were much better than those of controlled group ( Z =-4.597, -4.183, both P quality, postoperative analgesia, and reduce delirium in the elderly after total knee arthroplasty.
Elrasad, Amr; Khafagy, Mohammad G.; Shihada, Basem
of traffic, control and data. Control traffic are delay intolerant with higher priority than the data traffic. Closed form model for average ONU sleeping time and end-to-end data traffic delay are presented and evaluated. Our framework decouples
Liekweg, Kimberly; Christakis, Dimitri A.
BACKGROUND: Media use has been shown to negatively affect a child's sleep, especially in the context of evening use or with a television in the child's bedroom. However, little is known about how content choices and adult co-use affect this relationship. OBJECTIVE: To describe the impact of media content, timing, and use behaviors on child sleep. METHODS: These data were collected in the baseline survey and media diary of a randomized controlled trial on media use in children aged 3 to 5 years. Sleep measures were derived from the Children's Sleep Habits Questionnaire. Media diaries captured time, content title, and co-use of television, video-game, and computer usage; titles were coded for ratings, violence, scariness, and pacing. Nested linear regression models were built to examine the impact of timing, content, and co-use on the sleep problem score. RESULTS: On average, children consumed 72.9 minutes of media screen time daily, with 14.1 minutes occurring after 7:00 pm. Eighteen percent of parents reported at least 1 sleep problem; children with a bedroom television consumed more media and were more likely to have a sleep problem. In regression models, each additional hour of evening media use was associated with a significant increase in the sleep problem score (0.743 [95% confidence interval: 0.373–1.114]), as was daytime use with violent content (0.398 [95% confidence interval: 0.121–0.676]). There was a trend toward greater impact of daytime violent use in the context of a bedroom television (P = .098) and in low-income children (P = .07). CONCLUSIONS: Violent content and evening media use were associated with increased sleep problems. However, no such effects were observed with nonviolent daytime media use. PMID:21708803
Garrison, Michelle M; Liekweg, Kimberly; Christakis, Dimitri A
Media use has been shown to negatively affect a child's sleep, especially in the context of evening use or with a television in the child's bedroom. However, little is known about how content choices and adult co-use affect this relationship. To describe the impact of media content, timing, and use behaviors on child sleep. These data were collected in the baseline survey and media diary of a randomized controlled trial on media use in children aged 3 to 5 years. Sleep measures were derived from the Children's Sleep Habits Questionnaire. Media diaries captured time, content title, and co-use of television, video-game, and computer usage; titles were coded for ratings, violence, scariness, and pacing. Nested linear regression models were built to examine the impact of timing, content, and co-use on the sleep problem score. On average, children consumed 72.9 minutes of media screen time daily, with 14.1 minutes occurring after 7:00 pm. Eighteen percent of parents reported at least 1 sleep problem; children with a bedroom television consumed more media and were more likely to have a sleep problem. In regression models, each additional hour of evening media use was associated with a significant increase in the sleep problem score (0.743 [95% confidence interval: 0.373-1.114]), as was daytime use with violent content (0.398 [95% confidence interval: 0.121-0.676]). There was a trend toward greater impact of daytime violent use in the context of a bedroom television (P=.098) and in low-income children (P=.07). Violent content and evening media use were associated with increased sleep problems. However, no such effects were observed with nonviolent daytime media use. Copyright © 2011 by the American Academy of Pediatrics.
Lewin, Daniel S; Wang, Guanghai; Chen, Yao I; Skora, Elizabeth; Hoehn, Jessica; Baylor, Allison; Wang, Jichuan
Improving sleep health among adolescents is a national health priority and implementing healthy school start times (SSTs) is an important strategy to achieve these goals. This study leveraged the differences in middle school SST in a large district to evaluate associations between SST, sleep health, and academic performance. This cross-sectional study draws data from a county-wide surveillance survey. Participants were three cohorts of eighth graders (n = 26,440). The school district is unique because SST ranged from 7:20 a.m. to 8:10 a.m. Path analysis and probit regression were used to analyze associations between SST and self-report measures of weekday sleep duration, grades, and homework controlling for demographic variables (sex, race, and socioeconomic status). The independent contributions of SST and sleep duration to academic performance were also analyzed. Earlier SST was associated with decreased sleep duration (χ 2 = 173, p academic performance, and academic effort. Path analysis models demonstrated the independent contributions of sleep duration, SST, and variable effects for demographic variables. This is the first study to evaluate the independent contributions of SST and sleep to academic performance in a large sample of middle school students. Deficient sleep was prevalent, and the earliest SST was associated with decrements in sleep and academics. These findings support the prioritization of policy initiatives to implement healthy SST for younger adolescents and highlight the importance of sleep health education disparities among race and gender groups. Copyright © 2017 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Chapman, Daniel P.; Croft, Janet B.
BACKGROUND Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy change to address insufficient sleep in this population and potentially to improve students’ academic performance, reduce engagement in risk behaviors, and improve health. METHODS This paper reviews 38 reports examining the association between school start times, sleep, and other outcomes among adolescent students. RESULTS Most studies reviewed provide evidence that delaying school start time increases weeknight sleep duration among adolescents, primarily by delaying rise times. Most of the studies saw a significant increase in sleep duration even with relatively small delays in start times of half an hour or so. Later start times also generally correspond to improved attendance, less tardiness, less falling asleep in class, better grades, and fewer motor vehicle crashes. CONCLUSIONS Although additional research is necessary, research results that are already available should be disseminated to stakeholders to enable the development of evidence-based school policies. PMID:27040474
Wheaton, Anne G; Chapman, Daniel P; Croft, Janet B
Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy change to address insufficient sleep in this population and potentially to improve students' academic performance, reduce engagement in risk behaviors, and improve health. This article reviews 38 reports examining the association between school start times, sleep, and other outcomes among adolescent students. Most studies reviewed provide evidence that delaying school start time increases weeknight sleep duration among adolescents, primarily by delaying rise times. Most of the studies saw a significant increase in sleep duration even with relatively small delays in start times of half an hour or so. Later start times also generally correspond to improved attendance, less tardiness, less falling asleep in class, better grades, and fewer motor vehicle crashes. Although additional research is necessary, research results that are already available should be disseminated to stakeholders to enable the development of evidence-based school policies. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.
Sabrina Wulff Pabilonia; Charlene Marie Kalenkoski
Recent research suggests that working while in high school reduces the amount of time students spend doing homework. However, an additional hour of work leads to a reduction in homework by much less than one hour, suggesting a reduction in other activities. This paper uses data from the 2003-2007 American Time Use Surveys (ATUS) to investigate the effects of market work on the time students spend on homework, sleeping, household work, and screen time. Results show that an increase in paid wor...
Hagewoud, Roelina; Whitcomb, Shamiso N.; Heeringa, Amarins N.; Havekes, Robbert; Koolhaas, Jaap M.; Meerlo, Peter
Study Objectives: Sleep deprivation negatively affects memory consolidation, especially in the case of hippocampus-dependent memories. Studies in rodents have shown that 5 hours of sleep deprivation immediately following footshock exposure selectively impairs the formation of a contextual fear
Thivel, David; Isacco, Laurie; Aucouturier, Julien; Pereira, Bruno; Lazaar, Nordine; Ratel, Sébastien; Doré, Eric; Duché, Pascale
In the context of childhood obesity progression, sleep patterns have been associated with unhealthy eating habits and energy intake. The association between several eating habits and sleep patterns in children has been recently studied. The aim of this study was to explore the association between sleep patterns, eating habits, and physical fitness in primary school children. A total of 236 children of 6 to 10 years old were recruited. Anthropometric characteristics and body composition were measured, and cardiorespiratory (20-m shuttle run test) and musculoskeletal (squat jump and cycling peak power) fitness tests were performed. Parents were asked to fill out an eating habits questionnaire, and children were classified into 4 categories as a function of the number of eating risk factors they presented. Parents completed a questionnaire about their child's bedtime and waking hours during weekdays and weekends. Weight (p habits (p habits in primary school children. It seems necessary to consider the number of unhealthy eating habits adopted by children when studying these associations.
Graeber, R. Curtis; Lauber, John K.; Connell, Linda J.; Gander, Philippa H.
An international research team has carried out an electroencephalographic study of sleep and wakefulness in flight crews operating long-haul routes across seven or eight time zones. Following baseline recordings, volunteer crews (n = 56) from four airlines spent their first outbound layover at a sleep laboratory. This paper provides an overview of the project's history, its research design, and the standardization of procedures. The overall results are remarkably consistent among the four participating laboratories and strongly support the feasibility of cooperative international sleep research in the operational arena.
Antoniadis, Antonios; Huang, Chien-Chung; Ott, Sebastian
We study classical deadline-based preemptive scheduling of tasks in a computing environment equipped with both dynamic speed scaling and sleep state capabilities: Each task is specified by a release time, a deadline and a processing volume, and has to be scheduled on a single, speed-scalable processor that is supplied with a sleep state. In the sleep state, the processor consumes no energy, but a constant wake-up cost is required to transition back to the active state. In contrast to speed sc...
Lillis, Teresa A; Hamilton, Nancy A; Pressman, Sarah D; Khou, Christina S
This study investigated the relationship of daytime maternal napping, exercise, caffeine, and alcohol intake to objective and subjective sleep indices. Sixty healthy, nondepressed, first-time mothers between 3 and 6 months postpartum. Seven consecutive days of online behavior diaries, sleep diaries, and wrist actigraphy, collecting Total Sleep Time (TST), Sleep Onset Latency (SOL), and Wake After Sleep Onset (WASO). After controlling for infant age, employment status, infant feeding method, and infant sleeping location, mixed linear models showed that longer average exercise durations were associated with longer average TST, and longer average nap durations were associated with longer average WASO durations. Significant within-person differences in TST and SOL were also observed, such that, on days when participants exercised and napped longer than average, their respective TST and SOL durations that night were longer. Shorter nap durations and longer exercise durations were associated with longer TST, shorter SOL, and reduced WASO. Even small changes in daily exercise and napping behaviors could lead to reliable improvements in postpartum maternal sleep.
Perkinson-Gloor, Nadine; Lemola, Sakari; Grob, Alexander
Sleep timing undergoes profound changes during adolescence, often resulting in inadequate sleep duration. The present study examines the relationship of sleep duration with positive attitude toward life and academic achievement in a sample of 2716 adolescents in Switzerland (mean age: 15.4 years, SD = 0.8), and whether this relationship is…
Dewald, J.F.; Meijer, A.M.; Oort, F.J.; Kerkhof, G.A.; Bögels, S.M.
This prospective quasi-experiment (N=175; mean age: 15.14 years) investigates changes in adolescents' sleep from low-stress (regular school week) to high-stress times (exam week) and examines the (moderating) role of chronic sleep reduction, baseline stress, and gender. Sleep was monitored over
Dewald, Julia F.; Meijer, Anne Marie; Oort, Frans J.; Kerkhof, Gerard A.; Bögels, Susan M.
This prospective quasi-experiment (N = 175; mean age = 15.14 years) investigates changes in adolescents' sleep from low-stress (regular school week) to high-stress times (exam week), and examines the (moderating) role of chronic sleep reduction, baseline stress, and gender. Sleep was monitored over
Blunden, Sarah L; Thompson, Kirrilly R; Dawson, Drew
In Australia, as in many Westernised industrialised nations, the majority of families encourage infants to sleep alone or 'solo' from an early age. Sleeping solo can increase night time crying, which in turn disrupts sleep for both parent and infant. Night time waking and crying are frequently culturally constructed as behavioural sleep 'problems'. The pursuit of solo sleeping is thus achieved through 'behavioural sleep treatments' that teach an infant to sleep alone. Some behavioural extinction treatments necessitate a parent leaving an infant to cry for extended periods unattended, a practice reportedly difficult for parents. Despite parent's anxieties, and the potential (though little studied) stress to the infant, the pursuit of those behavioural sleep treatments are advocated by many psychologists and clinicians as acceptable and necessary interventions. This paper questions this necessity and critically reviews and debates these methods from biological, anthropological and cultural perspectives. Specifically, it considers Foucaultian, Leidloffian, attachment and behavioural perspectives. The central debate in this paper is if and why an infant's nocturnal cries should be ignored. It challenges the aetiology and acceptance of the status quo in the hope of revisiting the underlying belief that these methods are necessary. In doing so, the paper theorises the ways in which current sleep training techniques do or do not satisfy the needs of infants and their parents and questions the extent to which they can be reconciled. The paper posits an agenda for further research in the area that may facilitate the reconciliation of the needs of parents and those of their infants. Copyright © 2010 Elsevier Ltd. All rights reserved.
Lopez-Minguez, J.; Morosoli, J. J.; Madrid, J. A.; Garaulet, M.; Ordoñana, J. R.
Siesta is a relevant aspect of sleep due to its posited relationship with health or cognitive function. However, unlike night-time sleep, studies about daytime-sleep determinants and characteristics are scarce, and the genetic/environmental structure of siesta is still unknown. Our aim was to explore the relative contribution of genetic and environmental factors to variation in sleep-wake rhythm, measured by a continuous assessment of temperature-activity-position (TAP), which allows for diur...
Seehagen, Sabine; Konrad, Carolin; Herbert, Jane S.; Schneider, Silvia
The potential benefits of infant sleep for memory processing are largely unexplored. Here we show evidence that having an extended nap (≥30 min) within 4 h of learning helps 6- and 12-month-old infants to retain their memories for new behaviors across a 4- and 24-h delay. These results suggest that infants rely on frequent naps for the formation of long-term memories.
Gander, Philippa H.; Myhre, Grete; Graeber, R. Curtis; Lauber, John K.; Andersen, Harald T.
The adjustment of sleep-wake patterns and the circadian temperature rhythm was monitored in nine Royal Norwegian Airforce volunteers operating P-3 aircraft during a westward training deployment across nine time zones. Subjects recorded all sleep and nap times, rated nightly sleep quality, and completed personality inventories. Rectal temperature, heart rate, and wrist activity were continuously monitored. Adjustment was slower after the return eastward flight than after the outbound westward flight. The eastward flight produced slower readjustment of sleep timing to local time and greater interindividual variability in the patterns of adjustment of sleep and temperature. One subject apparently exhibited resynchronization by partition, with the temperature rhythm undergoing the reciprocal 15-h delay. In contrast, average heart rates during sleep were significantly elevated only after westward flight. Interindividual differences in adjustment of the temperature rhythm were correlated with some of the personality measures. Larger phase delays in the overall temperature waveform (as measured on the 5th day after westward flight) were exhibited by extraverts, and less consistently by evening types.
Soffer-Dudek, Nirit; Sadeh, Avi; Dahl, Ronald E; Rosenblat-Stein, Shiran
There is deepening understanding of the effects of sleep on emotional information processing. Emotion information processing is a key aspect of social competence, which undergoes important maturational and developmental changes in adolescence; however, most research in this area has focused on adults. Our aim was to test the links between sleep and emotion information processing during early adolescence. Sleep and facial information processing were assessed objectively during 3 assessment waves, separated by 1-year lags. Data were obtained in natural environments-sleep was assessed in home settings, and facial information processing was assessed at school. 94 healthy children (53 girls, 41 boys), aged 10 years at Time 1. N/A. Facial information processing was tested under neutral (gender identification) and emotional (emotional expression identification) conditions. Sleep was assessed in home settings using actigraphy for 7 nights at each assessment wave. Waking > 5 min was considered a night awakening. Using multilevel modeling, elevated night awakenings and decreased sleep efficiency significantly predicted poor performance only in the emotional information processing condition (e.g., b = -1.79, SD = 0.52, confidence interval: lower boundary = -2.82, upper boundary = -0.076, t(416.94) = -3.42, P = 0.001). Poor sleep quality is associated with compromised emotional information processing during early adolescence, a sensitive period in socio-emotional development.
Bapat, Radhika; van Geel, Mitch; Vedder, Paul
In this article physical activity, screen time, and academic work are studied as mediators between socio-economic status and sleep duration among school children in India. Participants were 268 school children aged 10?15 from Pune, India. They were sampled from private schools and impoverished public schools. We found that the highest socio-economic status children reported almost an hour and a half less sleep than their lowest socio-economic status counterparts. The lower socio-economic stat...
Akacem, Lameese D; Simpkin, Charles T; Carskadon, Mary A; Wright, Kenneth P; Jenni, Oskar G; Achermann, Peter; LeBourgeois, Monique K
The timing of the internal circadian clock shows large inter-individual variability across the lifespan. Although the sleep-wakefulness pattern of most toddlers includes an afternoon nap, the association between napping and circadian phase in early childhood remains unexplored. This study examined differences in circadian phase and sleep between napping and non-napping toddlers. Data were collected on 20 toddlers (34.2±2.0 months; 12 females; 15 nappers). Children followed their habitual napp...
de Leon, Jose
The Diagnostic and Statistical Manual of Mental Disorders (DSM-III), published in 1980, has led to a dead end, the DSM-V. Following the allegory of Sleeping Beauty, the DSM-III put European psychiatry to sleep; it now must wake up to create a 21st century psychiatric language for descriptive psychopathology and psychiatric nosology. Four topics are reviewed. First, the review of descriptive psychopathology focuses on: a) Chaslin's and Jaspers's books, and b) Schneider's transmittal of Jaspers's ideas and involvement with Kraepelin in incorporating neuroscience into psychiatric nosology. Second, US psychiatry's historic steps include: a) the pseudoscience of psychoanalysis, b) the low level of pre-DSM-III diagnostic expertise, c) the neo-Kraepelinian revolution which led to DSM-III, d) the failure to improve diagnostic skills, and e) the reprise of Kraepelin's marketing ("neuroscience will save psychiatry"). Third, the DSM-III devastated European psychiatry by destroying: a) the national textbooks which increased consistency but eliminated creative European thinking; and b) the Arbeitsgemenschaft fur Methodic und Dokumentation in der Psychiatrie, the most reasonable attempt to reach diagnostic agreement: start with symptoms/signs (first level) rather than disorders (second level). Fourth, Berrios elaborated upon Jaspers, who described psychiatry as a hybrid science and heterogeneous. Berrios affirmed that psychiatric symptoms/signs are hybrid. Some symptoms are in the "semantic space" and cannot be "explained" by neuroscience. Copyright © 2013 SEP y SEPB. Published by Elsevier España. All rights reserved.
Full Text Available The effects of color are already being used widely. For this reason, in this study, an attempt was made to use such effects of color to examine the changes in sleep onset through the use of the preferred and nonpreferred color light stimulation. Color light stimulations were randomly presented to the subjects, and based on these colors, the changes in sleep onset were examined through the EEG. Also, to quantify the physiological changes that were caused by each color light stimulation, the changes in the HRV were examined through ECG to determine the level of activation of the autonomous nervous system. The results showed that sleep onset time was changed based on the light stimulation. The result of the EEG analysis showed that sleep onset time was most significantly shortened in preferred color light stimulation. Also, the result of HRV was the fastest change about both the time domain and the frequency domain in the preferred color light stimulation. Therefore, because the preferred color light stimulation activated the parasympathetic nervous system, sleep was induced quickly. Also, by simply using the HRV, the differences in the index of HRV showed changes of sleep onset according to the color light stimulation.
Nothard, Michaela; Irvine, Susan; Theobald, Maryanne; Staton, Sally; Pattinson, Cassandra; Thorpe, Karen
Daytime sleep is a significant part of the daily routine for children attending early childhood education and care (ECEC) services in Australia and many other countries. The practice of sleep-time can account for a substantial portion of the day in ECEC and often involves a mandated sleep/rest period for all children, including older…
Full Text Available Background: a growing and broadly discussed literature has shown that the relationship between sleep duration and health is not linear. Not only are insomnia and insufficient sleep harmful to one’s health, but excessive sleep too is also not beneficial. This study tests the association between selfrated state of health and the duration and pattern of sleep: we discuss the losses and costs in terms of quality of life deriving from excessive sleep time.Methods: we use an ordered probit specification, applied to the Italian Survey on the Use of Time (sample of Italians aged fifteen and over who keep a diary for a working day.Results: we show that greater sleep duration is negatively correlated both with self-reported state of health and with self-reported health satisfaction, while respondents’ subjective perceptions of too much and too little sleep are associated with health conditions in the usual u-shaped way.Conclusions: the negative impact of long sleep on self-reported health is confirmed. However, the effect of short sleep on health conditions is positive, while a measure of decreasing sleep quality - comprising number of interruptions of sleep, insomnia and napping - is correlated to some extent with decreasing health. The public health consequences are still to be explored: the potential gains from sleep restriction are substantial, but little is known about the causal link or the risks. Further research is needed before taking policy decisions.
Lauridsen, Mette Munk; Frøjk, Jesper; de Muckadell, Ove B Schaffalitzky
of this study was to determine if sleep deprivation influences the CRT test. Eighteen cirrhosis patients and 27 healthy persons were tested when rested and after one night's sleep deprivation. The patients filled out validated sleep quality questionnaires. Seven patients (38 %) had unstable reaction times (a...... CRTindex change in the other patients' reaction speed or stability. Seven patients (38 %) reported poor sleep that was not related to their CRT tests before...... or after the sleep deprivation. In the healthy participants, the sleep deprivation slowed their reaction times by 11 % (p persons (25 %) destabilized them. The acute sleep deprivation normalized or improved the reaction time stability of the patients with a CRTindex below 1.9 and had...
Akacem, Lameese D; Simpkin, Charles T; Carskadon, Mary A; Wright, Kenneth P; Jenni, Oskar G; Achermann, Peter; LeBourgeois, Monique K
The timing of the internal circadian clock shows large inter-individual variability across the lifespan. Although the sleep-wakefulness pattern of most toddlers includes an afternoon nap, the association between napping and circadian phase in early childhood remains unexplored. This study examined differences in circadian phase and sleep between napping and non-napping toddlers. Data were collected on 20 toddlers (34.2±2.0 months; 12 females; 15 nappers). Children followed their habitual napping and non-napping sleep schedules (monitored with actigraphy) for 5 days before an in-home salivary dim light melatonin onset (DLMO) assessment. On average, napping children fell asleep during their nap opportunities on 3.6±1.2 of the 5 days before the DLMO assessment. For these napping children, melatonin onset time was 38 min later (p = 0.044; d = 0.93), actigraphically-estimated bedtime was 43 min later (p = 0.014; d = 1.24), sleep onset time was 59 min later (p = 0.006; d = 1.46), and sleep onset latency was 16 min longer (p = 0.030; d = 1.03) than those not napping. Midsleep and wake time did not differ by napping status. No difference was observed in the bedtime, sleep onset, or midsleep phase relationships with DLMO; however, the wake time phase difference was 47 min smaller for napping toddlers (p = 0.029; d = 1.23). On average, nappers had 69 min shorter nighttime sleep durations (p = 0.006; d = 1.47) and spent 49 min less time in bed (p = 0.019; d = 1.16) than non-nappers. Number of days napping was correlated with melatonin onset time (r = 0.49; p = 0.014). Our findings indicate that napping influences individual variability in melatonin onset time in early childhood. The delayed bedtimes of napping toddlers likely permits light exposure later in the evening, thereby delaying the timing of the clock and sleep. Whether the early developmental trajectory of circadian phase involves an advance associated with the decline in napping is a question necessitating
Lameese D Akacem
Full Text Available The timing of the internal circadian clock shows large inter-individual variability across the lifespan. Although the sleep-wakefulness pattern of most toddlers includes an afternoon nap, the association between napping and circadian phase in early childhood remains unexplored. This study examined differences in circadian phase and sleep between napping and non-napping toddlers. Data were collected on 20 toddlers (34.2±2.0 months; 12 females; 15 nappers. Children followed their habitual napping and non-napping sleep schedules (monitored with actigraphy for 5 days before an in-home salivary dim light melatonin onset (DLMO assessment. On average, napping children fell asleep during their nap opportunities on 3.6±1.2 of the 5 days before the DLMO assessment. For these napping children, melatonin onset time was 38 min later (p = 0.044; d = 0.93, actigraphically-estimated bedtime was 43 min later (p = 0.014; d = 1.24, sleep onset time was 59 min later (p = 0.006; d = 1.46, and sleep onset latency was 16 min longer (p = 0.030; d = 1.03 than those not napping. Midsleep and wake time did not differ by napping status. No difference was observed in the bedtime, sleep onset, or midsleep phase relationships with DLMO; however, the wake time phase difference was 47 min smaller for napping toddlers (p = 0.029; d = 1.23. On average, nappers had 69 min shorter nighttime sleep durations (p = 0.006; d = 1.47 and spent 49 min less time in bed (p = 0.019; d = 1.16 than non-nappers. Number of days napping was correlated with melatonin onset time (r = 0.49; p = 0.014. Our findings indicate that napping influences individual variability in melatonin onset time in early childhood. The delayed bedtimes of napping toddlers likely permits light exposure later in the evening, thereby delaying the timing of the clock and sleep. Whether the early developmental trajectory of circadian phase involves an advance associated with the decline in napping is a question
Full Text Available The globalization of markets requires continuous development of business holistic scenarios to ensure acceptable flexibility to satisfy customers. Continuous improvement of supply chain supposes continuous improvement of materials and products lead time and flow, material stocks and finished products stocks and increasing the number of suppliers close by as possible. The contribution of our study is to present holistic scenarios of total lead time improvement and innovation by implementing supply chain policy.
Strauch, I; Meier, B
A sample of 190 male and female "high school" students completed a sleep questionnaire for the first time when they were 10 to 14 years old. The survey was repeated five times at 2 year intervals. Ninety-three subjects answered the questionnaire each time. Subjective sleep need was assessed by the indicated wish for more sleep. The wish for more sleep was very pronounced, varying between 54.3% and 74.5% across the years. Individual consistency, however, was low since only 14.5% of the adolescents indicated the wish for more sleep in each survey, emphasizing the state dependency of this variable. Within each total sample, subjects with the wish for more sleep (MSL) and with sufficient sleep (SSL) were compared. Subjective sleep need was consistently validated by a syndrome of morning-tiredness. In the last two surveys, there was reduced time in bed (TIB) on weekdays in MSL subjects and longer TIB during vacation in surveys 2 through 5. Furthermore, MSL subjects more often showed irregular sleep habits. The previous sleep history of the MSL subjects in the last survey indicated that concomitants of the wish for more sleep were already experienced earlier in adolescence. The desired sleep duration of these subjects was 1.7 h longer than their current sleep on weekdays, an amount they had not obtained on weekdays since early adolescence. It is concluded that a substantial proportion of the adolescents seem to have had difficulties adapting to the general sleep time reduction occurring in adolescence.
The study was carried out to determine the values of whole blood coagulation time (WBCT), haematocrit (HM), haemaglobin (HB) and total protein (TP) of one hundred and eighteen apparently healthy turkeys reared under an extensive management system in Zaria. The mean values for WBCT, HM, HB and TP were 1.12 ...
Full Text Available This study on a breast cancer survivor suffering from cancer-related fatigue (CaRF and depression investigated the bidirectional relationship between cellular immune activity and subjective sleep. The 49-year-old patient (breast cancer diagnosis 5 years before the study, currently in remission collected her full urine output for 28 days in 12-h intervals (8:00 p.m. to 8:00 a.m. and 8:00 a.m. to 8:00 p.m.. These urine samples were used to determine urinary neopterin (cellular immune activation marker and creatinine concentrations via high-pressure liquid chromatography (HPLC. Each morning, the patient answered questions on five sleep variables: sleep quality (SQ, sleep recreational value (SRV, total sleep time (TST, total wake time (TWT, and awakenings during sleep period (ADS. For the purpose of this study, the time series of the nighttime urinary neopterin levels and the five sleep variables were determined. Using centered moving average (CMA smoothing and cross-correlational analysis, this study showed that increases in the positive sleep variables SQ and SRV were followed by urinary neopterin concentration decreases after 96–120 h (SQ, lag 4: r = −0.411; p = 0.044; SRV: lag 4: r = −0.472; p = 0.021 and 120–144 h (SRV, lag 5: r = −0.464; p = 0.026. Increases in the negative sleep variable TWT, by contrast, were followed by increases in urinary neopterin concentrations 72–96 h later (lag 3: r = 0.522; p = 0.009. No systematic effects in the other direction, i.e., from urinary neopterin levels to sleep, were observed in this study. Although preliminary, the findings of this study highlight the benefit of carefully investigating temporal delays and directions of effects when studying the dynamic relationship between sleep and immune variables in the natural context of everyday life.
Haire, Julia Christine Lydia; Ferguson, Sally Anne; Tilleard, James D; Negus, Paul; Dorrian, Jillian; Thomas, Matthew Jw
To evaluate the effect of working consecutive night shifts on sleep time, prior wakefulness, perceived levels of fatigue and psychomotor performance in a group of Australian emergency registrars. A prospective observational study with a repeated within-subjects component was conducted. Sleep time was determined using sleep diaries and activity monitors. Subjective fatigue levels and reciprocal reaction times were evaluated before and after day and night shifts. A total of 11 registrars participated in the study with 120 shifts analysed. Sleep time was found to be similar during consecutive night and day shifts. The mean number of hours spent awake before the end of a night shift was 14.33. Subjective fatigue scores were worst at the end of a night shift. There was no difference in reciprocal reaction time between the end of night shift and the start of day shift. Registrars sleep a similar amount of time surrounding night and day shifts. Despite reporting the highest levels of fatigue at the end of a night shift, there is no significant difference in reaction times at the end of night shift compared with the beginning of day shift. This correlates with the finding that at the end of night shift the registrars have been awake for less than 16 h, which is the point at which psychomotor performance is expected to decline. © 2012 The Authors. EMA © 2012 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.
Full Text Available Kimberly Fairbrother,1 Ben Cartner,1 Jessica R Alley,1 Chelsea D Curry,1, David L Dickinson,2 David M Morris,1 Scott R Collier1 1Vascular Biology and Autonomic Studies Laboratory, Department of Health and Exercise Science, 2Department of Economics, Appalachian State University, Boone, NC, USA Background: During nocturnal sleep, blood pressure (BP “dips” compared to diurnal BP, reducing stress on the cardiovascular system. Both the hypotensive response elicited by acute aerobic exercise and sleep quality can impact this dipping response. Purpose: The purpose of this study was to investigate the effects of aerobic exercise timing on circadian BP changes and sleep architecture. Materials and methods: Twenty prehypertensive subjects completed the study. During four test sessions, participants first completed a graded exercise test to exhaustion and then performed 30 minutes of treadmill exercise at 7 am (7A, 1 pm (1P, and 7 pm (7P in a random, counterbalanced order at 65% of the heart rate obtained at peak oxygen uptake. An ambulatory cuff was used to monitor BP responses during 24 hours following exercise, and an ambulatory sleep-monitoring headband was worn during sleep following each session. Results: Aerobic exercise at 7A invoked a greater dip in nocturnal systolic BP than exercise at 1P or 7P, although the greatest dip in nocturnal diastolic BP occurred following 7P. Compared to 1P, 7A also invoked greater time spent in deep sleep. Conclusion: These data indicate that early morning may be the most beneficial time to engage in aerobic exercise to enhance nocturnal BP changes and quality of sleep. Keywords: nocturnal dipping, prehypertension, aerobic exercise
Short, Michelle A; Gradisar, Michael; Lack, Leon C; Wright, Helen R; Dewald, Julia F; Wolfson, Amy R; Carskadon, Mary A
To test whether sleep duration on school nights differs between adolescents in Australia and the United States and, if so, whether this difference is explained by cultural differences in school start time, parental involvement in setting bedtimes, and extracurricular commitments. Three hundred eighty-five adolescents aged 13 to 18 years (M = 15.57, SD = 0.95; 60% male) from Australia and 302 adolescents aged 13 to 19 years (M = 16.03, SD = 1.19; 35% male) from the United States. Adolescents completed the School Sleep Habits Survey during class time, followed by an 8-day sleep diary. After controlling for age and gender, Australian adolescents obtained an average of 47 minutes more sleep per school night than those in the United States. Australian adolescents were more likely to have a parent-set bedtime (17.5% vs. 6.8%), have a later school start time (8:32 a.m. vs. 7:45 a.m.), and spend less time per day on extracurricular commitments (1 h 37 min vs. 2 h 41 min) than their U.S. peers. The mediating factors of parent-set bedtimes, later school start times, and less time spent on extracurricular activities were significantly associated with more total sleep. In addition to biological factors, extrinsic cultural factors significantly affect adolescent sleep. The present study highlights the importance of a cross-cultural, ecological approach and the impact of early school start times, lack of parental limit setting around bedtimes, and extracurricular load in limiting adolescent sleep.
Goelema, M S; Regis, M; Haakma, R; van den Heuvel, E R; Markopoulos, P; Overeem, S
This study aimed to establish the determinants of perceived sleep quality over a longer period of time, taking into account the separate contributions of actigraphy-based sleep measures and self-reported sleep indices. Fifty participants (52 ± 6.6 years; 27 females) completed two consecutive weeks of home monitoring, during which they kept a sleep-wake diary while their sleep was monitored using a wrist-worn actigraph. The diary included questions on perceived sleep quality, sleep-wake information, and additional factors such as well-being and stress. The data were analyzed using multilevel models to compare a model that included only actigraphy-based sleep measures (model Acti) to a model that included only self-reported sleep measures to explain perceived sleep quality (model Self). In addition, a model based on the self-reported sleep measures and extended with nonsleep-related factors was analyzed to find the most significant determinants of perceived sleep quality (model Extended). Self-reported sleep measures (model Self) explained 61% of the total variance, while actigraphy-based sleep measures (model Acti) only accounted for 41% of the perceived sleep quality. The main predictors in the self-reported model were number of awakenings during the night, sleep onset latency, and wake time after sleep onset. In the extended model, the number of awakenings during the night and total sleep time of the previous night were the strongest determinants of perceived sleep quality, with 64% of the variance explained. In our cohort, perceived sleep quality was mainly determined by self-reported sleep measures and less by actigraphy-based sleep indices. These data further stress the importance of taking multiple nights into account when trying to understand perceived sleep quality.
Herzig, David; Testorelli, Moreno; Olstad, Daniela Schäfer; Erlacher, Daniel; Achermann, Peter; Eser, Prisca; Wilhelm, Matthias
It is increasingly popular to use heart-rate variability (HRV) to tailor training for athletes. A time-efficient method is HRV assessment during deep sleep. To validate the selection of deep-sleep segments identified by RR intervals with simultaneous electroencephalography (EEG) recordings and to compare HRV parameters of these segments with those of standard morning supine measurements. In 11 world-class alpine skiers, RR intervals were monitored during 10 nights, and simultaneous EEGs were recorded during 2-4 nights. Deep sleep was determined from the HRV signal and verified by delta power from the EEG recordings. Four further segments were chosen for HRV determination, namely, a 4-h segment from midnight to 4 AM and three 5-min segments: 1 just before awakening, 1 after waking in supine position, and 1 in standing after orthostatic challenge. Training load was recorded every day. A total of 80 night and 68 morning measurements of 9 athletes were analyzed. Good correspondence between the phases selected by RR intervals vs those selected by EEG was found. Concerning root-mean-squared difference of successive RR intervals (RMSSD), a marker for parasympathetic activity, the best relationship with the morning supine measurement was found in deep sleep. HRV is a simple tool for approximating deep-sleep phases, and HRV measurement during deep sleep could provide a time-efficient alternative to HRV in supine position.
Next-generation passive optical network (PON) has been widely considered as a cost-effective broadband access technology. With the ever-increasing power saving concern, energy efficiency has been an important issue for its operations. In this paper, we present a novel sleep time sizing and scheduling framework that satisfies power efficient bandwidth allocation in PONs. We consider the downstream links from an optical line terminal (OLT) to an optical network unit (ONU). The ONU has two classes of traffic, control and data. Control traffic are delay intolerant with higher priority than the data traffic. Closed form model for average ONU sleeping time and end-to-end data traffic delay are presented and evaluated. Our framework decouples the dependency between ONU sleeping time and the QoS of the traffic.
Parent, Justin; Sanders, Wesley; Forehand, Rex
The purpose of this study was to examine the indirect effect of youth screen time (e.g., television, computers, smartphones, video games, and tablets) on behavioral health problems (i.e., internalizing, externalizing, and peer problems) through sleep duration and disturbances. The authors assessed a community sample of parents with a child in one of the following three developmental stages: young childhood (3-7 yrs; N = 209), middle childhood (8-12 yrs; N = 202), and adolescence (13-17 yrs; N = 210). Path analysis was used to test the hypothesized indirect effect model. Findings indicated that, regardless of the developmental stage of the youth, higher levels of youth screen time were associated with more sleep disturbances, which, in turn, were linked to higher levels of youth behavioral health problems. Children who have increased screen time are more likely to have poor sleep quality and problem behaviors.
Onyper, Serge V; Thacher, Pamela V; Gilbert, Jack W; Gradess, Samuel G
Path analysis was used to examine the relationship between class start times, sleep, circadian preference, and academic performance in college-aged adults. Consistent with observations in middle and high school students, college students with later class start times slept longer, experienced less daytime sleepiness, and were less likely to miss class. Chronotype was an important moderator of sleep schedules and daytime functioning; those with morning preference went to bed and woke up earlier and functioned better throughout the day. The benefits of taking later classes did not extend to academic performance, however; grades were somewhat lower in students with predominantly late class schedules. Furthermore, students taking later classes were at greater risk for increased alcohol consumption, and among all the factors affecting academic performance, alcohol misuse exerted the strongest effect. Thus, these results indicate that later class start times in college, while allowing for more sleep, also increase the likelihood of alcohol misuse, ultimately impeding academic success.
AASM standards of practice compliant validation of actigraphic sleep analysis from SOMNOwatch(TM) versus polysomnographic sleep diagnostics shows high conformity also among subjects with sleep disordered breathing
Dick, R; Schulz, J; Penzel, T; Fietze, I; Partinen, M; Hein, H
In recent AASM practice, parameter actimetry is cited to measure total sleep time in obstructive sleep apnoea patients, when polysomnography is not available. An actigraph was therefore compared to polysomnographic data in 28 subjects with known sleep disordered breathing. Total sleep time (TST), sleep period time (SPT), sleep efficiency (SE), sustained sleep efficiency (SSE), sleep onset latency (SL) and sleep/wake pattern were compared to gold standard polysomnography. The results of an epoch-by-epoch comparison of sleep/wake from actigraphy to sleep stages from polysomnography gave a sensitivity of 90.2%, a specificity of 95.2% and an overall accuracy of 85.9%. Correlations were moderately strong for SE (0.71, p < 0.001) and SSE (0.65, p < 0.001) and high for TST (0.89, p < 0.001), SPT (0.91, p < 0.001) and SL (0.89, p < 0.001). It was concluded that actigraphy is not identical with PSG recording but gives good results in sleep/wake patterns and predicting TST, SPT, SSE, SE and SL also in sleep apnoea patients not suffering from other sleep disorders. The difficult detection of correct sleep onset causes SSE and SL to be less predictable. Therefore a 15-epoch criterion was introduced and resulted in high correlation of 0.89 for sleep latency, but has to be tested on a bigger population
Frost, J. D., Jr.; Salamy, J. G.
The Skylab sleep-monitoring experiment simulated the timelines and environment expected during a 56-day Skylab mission. Two crewmembers utilized the data acquisition and analysis hardware, and their sleep characteristics were studied in an online fashion during a number of all night recording sessions. Comparison of the results of online automatic analysis with those of postmission visual data analysis was favorable, confirming the feasibility of obtaining reliable objective information concerning sleep characteristics during the Skylab missions. One crewmember exhibited definite changes in certain sleep characteristics (e.g., increased sleep latency, increased time Awake during first third of night, and decreased total sleep time) during the mission.
This study investigated the effects of inhalation aromatherapy on sleep disturbance in elderly individuals with dementia. In 19 subjects, normal sleep was observed for a 20-day control period, inhalation aromatherapy was then applied for a 20-day intervention period, and the control and intervention periods were compared. During the intervention period, essential oils were placed nightly on towels around the subjects' pillows. The measured sleep conditions were sleep latency, total sleep time, sleep efficacy, duration of the longest sustained sleep period, wake time after sleep onset, early morning awakening, total daytime sleep, and the Neuropsychiatric Inventory. Total sleep time was significantly longer in the intervention period than in the control period (p aromatherapy on symptoms of sleep disturbance in elderly individuals with dementia. PMID:28400839
Yu, Xingjian; Isobe, Takashi; Watanabe, Mitsuo; Liu, Huafeng
A novel crystal timing calibration method based on total variation (TV), abbreviated as ‘TV merge’, has been developed for a high-resolution positron emission tomography (PET) system. The proposed method was developed for a system with a large number of crystals, it can provide timing calibration at the crystal level. In the proposed method, the timing calibration process was formulated as a linear problem. To robustly optimize the timing resolution, a TV constraint was added to the linear equation. Moreover, to solve the computer memory problem associated with the calculation of the timing calibration factors for systems with a large number of crystals, the merge component was used for obtaining the crystal level timing calibration values. Compared with other conventional methods, the data measured from a standard cylindrical phantom filled with a radioisotope solution was sufficient for performing a high-precision crystal-level timing calibration. In this paper, both simulation and experimental studies were performed to demonstrate the effectiveness and robustness of the TV merge method. We compare the timing resolutions of a 22Na point source, which was located in the field of view (FOV) of the brain PET system, with various calibration techniques. After implementing the TV merge method, the timing resolution improved from 3.34 ns at full width at half maximum (FWHM) to 2.31 ns FWHM.
De Carli, Fabrizio; Nobili, Lino; Beelke, Manolo; Watanabe, Tsuyoshi; Smerieri, Arianna; Parrino, Liborio; Terzano, Mario Giovanni; Ferrillo, Franco
A number of phasic events influence sleep quality and sleep macrostructure. The detection of arousals and the analysis of cyclic alternating patterns (CAP) support the evaluation of sleep fragmentation and instability. Sixteen polygraphic overnight recordings were visually inspected for conventional Rechtscaffen and Kales scoring, while arousals were detected following the criteria of the American Sleep Disorders Association (ASDA). Three electroencephalograph (EEG) segments were associated to each event, corresponding to background activity, pre-arousal period and arousal. The study was supplemented by the analysis of time-frequency distribution of EEG within each subtype of phase A in the CAP. The arousals were characterized by the increase of alpha and beta power with regard to background. Within NREM sleep most of the arousals were preceded by a transient increase of delta power. The time-frequency evolution of the phase A of the CAP sequence showed a strong prevalence of delta activity during the whole A1, but high amplitude delta waves were found also in the first 2/3 s of A2 and A3, followed by desynchronization. Our results underline the strict relationship between the ASDA arousals, and the subtype A2 and A3 within the CAP: in both the association between a short sequence of transient slow waves and the successive increase of frequency and decrease of amplitude characterizes the arousal response.
Milojevich, Helen M; Lukowski, Angela F
Whereas previous research has indicated that sleep problems tend to co-occur with increased mental health issues in university students, relatively little is known about relations between sleep quality and mental health in university students with generally healthy sleep habits. Understanding relations between sleep and mental health in individuals with generally healthy sleep habits is important because (a) student sleep habits tend to worsen over time and (b) even time-limited experience of sleep problems may have significant implications for the onset of mental health problems. In the present research, 69 university students with generally healthy sleep habits completed questionnaires about sleep quality and mental health. Although participants did not report clinically concerning mental health issues as a group, global sleep quality was associated with mental health. Regression analyses revealed that nighttime sleep duration and the frequency of nighttime sleep disruptions were differentially related to total problems and clinically-relevant symptoms of psychological distress. These results indicate that understanding relations between sleep and mental health in university students with generally healthy sleep habits is important not only due to the large number of undergraduates who experience sleep problems and mental health issues over time but also due to the potential to intervene and improve mental health outcomes before they become clinically concerning.
Ong, Ju Lynn; Lo, June C; Gooley, Joshua J; Chee, Michael W L
To investigate sleep EEG changes in adolescents across 7 nights of sleep restriction to 5 h time in bed [TIB]) and 3 recovery nights of 9 h TIB. A parallel-group design, quasi-laboratory study was conducted in a boarding school. Fifty-five healthy adolescents (25 males, age = 15-19 y) who reported habitual TIBs of approximately 6 h on week nights (group average) but extended their sleep on weekends were randomly assigned to Sleep Restriction (SR) or Control groups. Participants underwent a 2-week protocol comprising 3 baseline nights (TIB = 9 h), 7 nights of sleep opportunity manipulation (TIB = 5 h for the SR and 9 h for the Control group), and 3 nights of recovery sleep (TIB = 9 h). Polysomnography was obtained on two baseline, three manipulation, and two recovery nights. Across the sleep restriction nights, total SWS duration was preserved relative to the 9 h baseline sleep opportunity, while other sleep stages were reduced. Considering only the first 5 h of sleep opportunity, SR participants had reduced N1 duration and wake after sleep onset (WASO), and increased total sleep time (TST), rapid eye movement (REM) sleep, and slow wave sleep (SWS) relative to baseline. Total REM sleep, N2, and TST duration remained above baseline levels by the third recovery sleep episode. In spite of preservation of SWS duration over multiple nights of sleep restriction, adolescents accustomed to curtailing nocturnal sleep on school day nights evidence residual effects on sleep macro-structure, even after three nights of recovery sleep. Older teenagers may not be as resilient to successive nights of sleep restriction as is commonly believed. © 2016 Associated Professional Sleep Societies, LLC.
Biggs, Sarah N.; Meltzer, Lisa J.; Tapia, Ignacio E.; Traylor, Joel; Nixon, Gillian M.; Horne, Rosemary S.C.; Doyle, Lex W.; Asztalos, Elizabeth; Mindell, Jodi A.; Marcus, Carole L.
Study Objectives: To compare sleep/wake patterns in children born preterm in Australia vs Canada and determine cultural differences in the relationship between parental perception of sleep and actual sleep behaviors. Methods: Australian and Canadian children born preterm were recruited from the Caffeine for Apnea of Prematurity trial (n = 188, 5–12 y) and underwent 14 days actigraphy monitoring. Parents completed the National Sleep Foundation 2004 Sleep in America questionnaire. Cross-cultural differences in sleep characteristics assessed by actigraphy and parent-reported questionnaire were examined. Correlational analyses determined the associations between parental perceptions of child sleep need and sleep behavior. Results: Actigraphy showed preterm children obtained, on average, 8 h sleep/night, one hour less than population recommendations for their age. There was no difference in total sleep time (TST) between Australian and Canadian cohorts; however, bed and wake times were earlier in Australian children. Bedtimes and TST varied by 60 minutes from night to night in both cohorts. Parent-reported child TST on the National Sleep Foundation questionnaire was 90 minutes longer than recorded by actigraphy. Both bedtime and TST on weekdays and weekends were related to parental perception of child sleep need in the Australian cohort. Only TST on weekdays was related to parental perception of child sleep need in the Canadian cohort. Conclusions: This study suggests that short sleep duration and irregular sleep schedules are common in children born preterm. Cultural differences in the association between parental perception of child sleep need and actual sleep behaviors provide important targets for future sleep health education. Citation: Biggs SN, Meltzer LJ, Tapia IE, Traylor J, Nixon GM, Horne RS, Doyle LW, Asztalos E, Mindell JA, Marcus CL. Sleep/wake patterns and parental perceptions of sleep in children born preterm. J Clin Sleep Med 2016;12(5):711–717
Staiano, Amanda E; Broyles, Stephanie T; Katzmarzyk, Peter T
This cross-sectional study examined differences in children's health behaviors during school term (ST) versus school holiday (SH: June-July) and how associations changed when weather characteristics were considered. Children aged 5-18 years (n = 406) from a subtropical climate reported behaviors over 20 months. Multivariable regression models controlling for age, sex, race and body mass index z-score (BMIz) were used to examine associations between SH and each behavior. A second model included heat index, precipitation and daylight hours. Strenuous activity, moderate activity, total activity and TV viewing were significantly higher during SH than ST. After adjusting for weather characteristics, total activity remained significantly higher during SH, but the association with TV viewing was attenuated. Youth surveyed during high precipitation were significantly less likely to meet physical activity guidelines. There were no significant associations between SH and meeting sleep, physical activity or screen-time guidelines. Weather characteristics influenced associations between SH and youth's physical activity and TV viewing.
Hramov, Alexander E.; Sitnikova, Evgenija Y.; Pavlov, Alexey N.; Grubov, Vadim V.; Koronovskii, Alexey A.; Khramova, Marina V.
Sleep spindles are known to appear spontaneously in the thalamocortical neuronal network of the brain during slow-wave sleep; pathological processes in the thalamocortical network may be the reason of the absence epilepsy. The aim of the present work is to study developed changes in the time-frequency structure of sleep spindles during the progressive development of the absence epilepsy in WAG/Rij rats. EEG recordings were made at age 7 and 9 months. Automatic recognition and subsequent analysis of sleep spindles on the EEG were performed using the continuous wavelet transform. The duration of epileptic discharges and the total duration of epileptic activity were found to increase with age, while the duration of sleep spindles, conversely, decreased. In terms of the mean frequency, sleep spindles could be divided into three classes: `slow' (mean frequency 9.3Hz), `medium' (11.4Hz), and `fast' (13.5Hz). Slow and medium (transitional) spindles in five-month-old animals showed increased frequency from the beginning to the end of the spindle. The more intense the epilepsy is, the shorter are the durations of spindles of all types. The mean frequencies of `medium' and `fast' spindles were higher in rats with more intense signs of epilepsy. Overall, high epileptic activity in WAG/Rij rats was linked with significant changes in spindles of the transitional type, with less marked changes in the two traditionally identified types of spindle, slow and fast.
Bub, Kristen L.; Buckhalt, Joseph A.; El-Sheikh, Mona
Relations between changes in children's cognitive performance and changes in sleep problems were examined over a 3-year period, and family socioeconomic status, child race/ethnicity, and gender were assessed as moderators of these associations. Participants were 250 second- and third-grade (8-9 years old at Time 1) boys and girls. At each…
Full Text Available A survey on sleep schedule, sleep health, school performance and school start times was conducted in 1,941 adolescents. A high level of early and circadian-disadvantaged sleep/wake schedules during weekdays was observed. Shorter sleep duration on weekdays was reported, especially in upper classmen. Complaints of inadequate sleep and sleepiness during weekdays, alarm clock use, and napping were prevalent. Night awakening and prolonged sleep onset were common and associated with poor school performance. Students with a sleep length of less than 7 hours on both weekdays and weekends exhibited poorer performance, while those who made up this sleep loss on weekends did not. The total number of poor sleep factors in an individual also correlated with poor school performance. Earlier school start times were associated with a perception of poor sleep quality, shorter sleep duration and more sleep health problems. We conclude that sleep inadequacies and sleep health problems were prevalent in this population, especially in those who started school earlier in the morning, and that these poor sleep factors were associated with school performance.
Hertenstein, Elisabeth; Nissen, Christoph; Riemann, Dieter; Feige, Bernd; Baglioni, Chiara; Spiegelhalder, Kai
Differences between subjective sleep perception and sleep determined by polysomnography (PSG) are prevalent, particularly in patients with primary insomnia, indicating that the two measures are partially independent. To identify individualized treatment strategies, it is important to understand the potentially different mechanisms influencing subjective and PSG-determined sleep. The aim of this study was to investigate to what extent three major components of insomnia models, i.e., sleep effort, dysfunctional beliefs and attitudes about sleep, and presleep arousal, are associated with subjective insomnia severity and PSG-determined sleep. A sample of 47 patients with primary insomnia according to DSM-IV criteria and 52 good sleeper controls underwent 2 nights of PSG and completed the Glasgow Sleep Effort Scale, the Dysfunctional Beliefs and Attitudes about Sleep Scale, the Pre-Sleep Arousal Scale and the Insomnia Severity Index. Regression analyses were conducted to investigate the impact of the three predictors on subjective insomnia severity and PSG- determined total sleep time. All analyses were adjusted for age, gender, depressive symptoms and group status. The results showed that subjective insomnia severity was associated positively with sleep effort. PSG-determined total sleep time was associated negatively with somatic presleep arousal and dysfunctional beliefs and attitudes about sleep. This pattern of results provides testable hypotheses for prospective studies on the impact of distinct cognitive and somatic variables on subjective insomnia severity and PSG-determined total sleep time. © 2015 European Sleep Research Society.
Felder, Jennifer N; Epel, Elissa S; Coccia, Michael; Puterman, Eli; Prather, Aric A
We examined effects of daily rumination and suppression in response to stressors on objective and subjective sleep among mothers. Participants were 183 mothers, including chronically stressed mothers of children with an autism spectrum disorder (M-ASD; n = 92) and age-matched mothers of neurotypical children (M-NT; n = 91). In an intensive longitudinal design, participants provided reports of daily rumination and suppression, nightly objective actigraphy-defined sleep and nightly subjective sleep quality for seven consecutive days at baseline, 9 months and 18 months. Total sleep time, sleep fragmentation, sleep onset latency, and subjective sleep quality. Among M-NT with above average depressive symptoms, higher daily rumination was associated with shorter total sleep time. Rumination was associated with more sleep fragmentation among M-NT at the trend level. Rumination was not associated with sleep onset latency among M-NT, or with any sleep outcomes among M-ASD. Suppression was not associated with any sleep outcomes. We provide novel evidence of the effect of rumination on objectively measured sleep duration among M-NT. Coping was not related to sleep among M-ASD. Given the prevalence of poor sleep among mothers, future work should examine modifiable factors perpetuating sleep disturbance.
Gumenyuk, Valentina; Korzyukov, Oleg; Roth, Thomas; Bowyer, Susan M; Drake, Christopher L
Chronic sleep loss has been associated with increased daytime sleepiness, as well as impairments in memory and attentional processes. In the present study, we evaluated the neuronal changes of a pre-attentive process of wake auditory sensory gating, measured by brain event-related potential (ERP)--P50 in eight normal sleepers (NS) (habitual total sleep time (TST) 7 h 32 m) vs. eight chronic short sleeping individuals (SS) (habitual TST ≤6 h). To evaluate the effect of sleep extension on sensory gating, the extended sleep condition was performed in chronic short sleeping individuals. Thus, one week of time in bed (6 h 11 m) corresponding to habitual short sleep (hSS), and one week of extended time (∼ 8 h 25 m) in bed corresponding to extended sleep (eSS), were counterbalanced in the SS group. The gating ERP assessment was performed on the last day after each sleep condition week (normal sleep and habitual short and extended sleep), and was separated by one week with habitual total sleep time and monitored by a sleep diary. We found that amplitude of gating was lower in SS group compared to that in NS group (0.3 µV vs. 1.2 µV, at Cz electrode respectively). The results of the group × laterality interaction showed that the reduction of gating amplitude in the SS group was due to lower amplitude over the left hemisphere and central-midline sites relative to that in the NS group. After sleep extension the amplitude of gating increased in chronic short sleeping individuals relative to their habitual short sleep condition. The sleep condition × frontality interaction analysis confirmed that sleep extension significantly increased the amplitude of gating over frontal and central brain areas compared to parietal brain areas.
Full Text Available Chronic sleep loss has been associated with increased daytime sleepiness, as well as impairments in memory and attentional processes. In the present study, we evaluated the neuronal changes of a pre-attentive process of wake auditory sensory gating, measured by brain event-related potential (ERP--P50 in eight normal sleepers (NS (habitual total sleep time (TST 7 h 32 m vs. eight chronic short sleeping individuals (SS (habitual TST ≤6 h. To evaluate the effect of sleep extension on sensory gating, the extended sleep condition was performed in chronic short sleeping individuals. Thus, one week of time in bed (6 h 11 m corresponding to habitual short sleep (hSS, and one week of extended time (∼ 8 h 25 m in bed corresponding to extended sleep (eSS, were counterbalanced in the SS group. The gating ERP assessment was performed on the last day after each sleep condition week (normal sleep and habitual short and extended sleep, and was separated by one week with habitual total sleep time and monitored by a sleep diary. We found that amplitude of gating was lower in SS group compared to that in NS group (0.3 µV vs. 1.2 µV, at Cz electrode respectively. The results of the group × laterality interaction showed that the reduction of gating amplitude in the SS group was due to lower amplitude over the left hemisphere and central-midline sites relative to that in the NS group. After sleep extension the amplitude of gating increased in chronic short sleeping individuals relative to their habitual short sleep condition. The sleep condition × frontality interaction analysis confirmed that sleep extension significantly increased the amplitude of gating over frontal and central brain areas compared to parietal brain areas.
Bronwyn K. Clark
Full Text Available Data from the Australian Longitudinal Study on Women’s Health were used to examine how work was associated with time spent sleeping, sitting and in physical activity (PA, in working women. Young (31–36 years; 2009 and mid-aged (59–64 years; 2010 women reported sleep (categorised as shorter ≤6 h/day and longer ≥8 h/day and sitting time (work, transport, television, non-work computer, and other; summed for total sitting time on the most recent work and non-work day; and moderate and vigorous PA (categorised as meeting/not meeting guidelines in the previous week. Participants reported occupation (manager/professional; clerical/sales; trades/transport/labourer, work hours (part-time; full-time and work pattern (shift/night; not shift/night. The odds of shorter sleep on work days was higher in both cohorts for women who worked shift or night hours. Longer sitting time on work days, made up primarily of sitting for work, was found for managers/professionals, clerical/sales and full-time workers. In the young cohort, clerical/sales workers and in the mid-aged cohort, full-time workers were less likely to meet PA guidelines. These results suggest multiple behaviour interventions tailored to work patterns and occupational category may be useful to improve the sleep, sitting and activity of working women.
Graham, Christopher D; Kyle, Simon D
Functional neurological disorders (FND) are disabling conditions for which there are few empirically-supported treatments. Disturbed sleep appears to be part of the FND context; however, the clinical importance of sleep disturbance (extent, characteristics and impact) remains largely unknown. We described sleep quality in two samples, and investigated the relationship between sleep and FND-related functional impairment. We included a sample recruited online via patient charities (N=205) and a consecutive clinical sample (N=20). Participants completed validated measures of sleep quality and sleep characteristics (e.g. total sleep time, sleep efficiency), mood, and FND-related functional impairment. Poor sleep was common in both samples (89% in the clinical range), which was characterised by low sleep efficiency (M=65.40%) and low total sleep time (M=6.05h). In regression analysis, sleep quality was negatively associated with FND-related functional impairment, accounting for 16% of the variance and remaining significant after the introduction of mood variables. These preliminary analyses suggest that subjective sleep disturbance (low efficiency, short sleep) is common in FND. Sleep quality was negatively associated with the functional impairment attributed to FND, independent of depression. Therefore, sleep disturbance may be a clinically important feature of FND. Copyright © 2017 Elsevier B.V. All rights reserved.
Ursin, Reidun; Bjorvatn, Bjørn; Holsten, Fred
To report the distribution of various sleep parameters in a population-based study. Population-based cross-sectional study with self-administered questionnaires. Conducted as part of the Hordaland Health Study '97-'99 in collaboration with the Norwegian National Health Screening Service. 8860 subjects, aged 40 to 45 years, answered the sleep questionnaire part of the study. N/A. Reports on habitual bedtimes, rise times, subjective sleep need, and various sleep characteristics were used in this study. Mean (+/- SD) nocturnal sleep duration during weekdays in men was 6 hours 52 minutes (+/- 55 minutes); in women 7 hours 11 minutes (+/- 57 minutes). Mean subjective sleep need was 7 hours 16 minutes (+/- 52 minutes) in men; 7 hours 45 minutes (+/- 52 minutes) in women. Sleep duration was shorter in shift workers and longer in married subjects and in those living in rural areas. Subjective sleep need was higher in subjects reporting poor subjective health and in subjects living in rural areas. In total, these variables accounted for only around 3% of the variance in sleep duration and sleep need. Ten percent of the men and 12.2% of the women reported frequent insomnia. The wide distribution of sleep duration and subjective sleep need indicate large interindividual variations in these parameters. There were pronounced sex differences in these variables and in most of the sleep characteristics studied. Shift work, urban-rural living, marital status, and education in men were sources of significant, but small, variations in sleep duration.
Full Text Available It is well established that sleep spindles (bursts of oscillatory brain electrical activity are significant indicators of learning, memory and some disease states. Therefore, many attempts have been made to detect these hallmark patterns automatically. In this pilot investigation, we paid special attention to nonlinear chaotic features of EEG signals (in combination with linear features to investigate the detection and prediction of sleep spindles. These nonlinear features included: Higuchi's, Katz's and Sevcik's Fractal Dimensions, as well as the Largest Lyapunov Exponent and Kolmogorov's Entropy. It was shown that the intensity map of various nonlinear features derived from the constructive interference of spindle signals could improve the detection of the sleep spindles. It was also observed that the prediction of sleep spindles could be facilitated by means of the analysis of these maps. Two well-known classifiers, namely the Multi-Layer Perceptron (MLP and the K-Nearest Neighbor (KNN were used to distinguish between spindle and non-spindle patterns. The MLP classifier produced a~high discriminative capacity (accuracy = 94.93%, sensitivity = 94.31% and specificity = 95.28% with significant robustness (accuracy ranging from 91.33% to 94.93%, sensitivity varying from 91.20% to 94.31%, and specificity extending from 89.79% to 95.28% in separating spindles from non-spindles. This classifier also generated the best results in predicting sleep spindles based on chaotic features. In addition, the MLP was used to find out the best time window for predicting the sleep spindles, with the experimental results reaching 97.96% accuracy.
Ortaç Ersoy, Ebru; Fırat, Hikmet; Akaydın, Sevgi; Özkan, Yeşim; Durusu, Mine; Darılmaz Yüce, Gülbahar; Ergün, Recai; Topeli, Arzu; Ardıç, Sadık
Obstructive sleep apnea (OSA) is associated with cardiovascular morbidity and mortality. Deficiency of nitric oxide (NO) and plasma levels of homocystein have been implicated in the pathogenesis of cardiovascular disease. OSA results in oxygen desaturation and arousal from sleep. Free oxygen radicals can be produced by hypoxia-reoxygenation. To test for the hypothesis that OSA is associated with cardiovascular morbidity, we investigated levels of homocystein, NO and total antioxidant capacity in OSA patients with and without coronary artery disease (CAD) in comparison with normal subjects and patients with CAD without OSA. Polysomnography was performed in 27 patients who had a myocardial infarction and in 25 patients without evidence of CAD. Patients were grouped according their polysomnography results as OSA with CAD (group 1), OSA without CAD (group 2), CAD (group 3), and normal (group 4) . Levels of homocystein, NO and total antioxidant capacity were determined after an overnight fasting. Data were analysed with parametric and non parametric statistical tests. According to apnea-hypopnea index (AHI) 44.4% of CAD patients were OSA. After polysomnographic evaluation, the patients were re-distributed as follows: OSA with CAD (n= 12), OSA without CAD (n= 14), CAD (n= 15), and normal (n= 11). Homocystein levels were higher in 3 groups compared to controls. AHI, MDI and desaturation time was higher in three -vessel disease compared to one and two- vessel diseases (p< 0.05). NO levels were correlated with the period of oxygen desaturation (r: -0.45, p= 0.031). The antioxidant capacity did not differ between OSA and healthy groups. OSA is frequent in CAD. AHI, MDI and desaturation time are higher in patients with severe CAD. It is important to evaluate OSA patients for CAD.
Yasova Barbeau, Daphna; Weiss, Michael D.
The purpose of this review is to serve as an introduction to understanding sleep in the fetus, the preterm neonate and the term neonate. Sleep appears to have numerous important roles, particularly in the consolidation of new information. The sleep cycle changes over time, neonates spend the most time in active sleep and have a progressive shortening of active sleep and lengthening of quiet sleep. Additionally, the sleep cycle is disrupted by many things including disease state and environmen...
Kalolella, Admirabilis Beno
A 49 years old man, known case of bronchial asthma for 43 years, with history of frequent asthmatic attacks, usually responding to double dose of intravenous Aminophylline and double dose of Hydrocortisone was received at medical emergency care unit at midnight with night-time asthma attack. The attack did not settle with Aminophylline single Intravenous injection. He was then admitted and put in supine sleep position for re-evaluation while his asthma symptoms were monitored while waiting for the medical officer's evaluation of his asthma status. After 3 hours of observation, asthma symptoms were relieved, and patient was discharged home and advised to sleep in supine position throughout every night to prevent asthma symptoms. The patient was followed up through nighttime sleep diary for one month. After one month period of monitoring, the patient had significance reduction in asthma symptoms and reduced night time medication, reduced episodes of night awakening due to asthma symptoms, and improved capability for normal works. This case report describes a novel approach of management and prophylaxis of asthmatic episodes through sleeping position that reduces and control asthma symptoms resulting in reduced drug consumption.
Sabra M Abbott
Full Text Available Sleep-wake cycling is controlled by the complex interplay between two brain systems, one which controls vigilance state, regulating the transition between sleep and wake, and the other circadian, which communicates time-of-day. Together, they align sleep appropriately with energetic need and the day-night cycle. Neural circuits connect brain stem sites that regulate vigilance state with the suprachiasmatic nucleus (SCN, the master circadian clock, but the function of these connections has been unknown. Coupling discrete stimulation of pontine nuclei controlling vigilance state with analytical chemical measurements of intra-SCN microdialysates in mouse, we found significant neurotransmitter release at the SCN and, concomitantly, resetting of behavioral circadian rhythms. Depending upon stimulus conditions and time-of-day, SCN acetylcholine and/or glutamate levels were augmented and generated shifts of behavioral rhythms. These results establish modes of neurochemical communication from brain regions controlling vigilance state to the central circadian clock, with behavioral consequences. They suggest a basis for dynamic integration across brain systems that regulate vigilance states, and a potential vulnerability to altered communication in sleep disorders.
Abbott, Sabra M; Arnold, Jennifer M; Chang, Qing; Miao, Hai; Ota, Nobutoshi; Cecala, Christine; Gold, Paul E; Sweedler, Jonathan V; Gillette, Martha U
Sleep-wake cycling is controlled by the complex interplay between two brain systems, one which controls vigilance state, regulating the transition between sleep and wake, and the other circadian, which communicates time-of-day. Together, they align sleep appropriately with energetic need and the day-night cycle. Neural circuits connect brain stem sites that regulate vigilance state with the suprachiasmatic nucleus (SCN), the master circadian clock, but the function of these connections has been unknown. Coupling discrete stimulation of pontine nuclei controlling vigilance state with analytical chemical measurements of intra-SCN microdialysates in mouse, we found significant neurotransmitter release at the SCN and, concomitantly, resetting of behavioral circadian rhythms. Depending upon stimulus conditions and time-of-day, SCN acetylcholine and/or glutamate levels were augmented and generated shifts of behavioral rhythms. These results establish modes of neurochemical communication from brain regions controlling vigilance state to the central circadian clock, with behavioral consequences. They suggest a basis for dynamic integration across brain systems that regulate vigilance states, and a potential vulnerability to altered communication in sleep disorders.
Baig, Mirza M; Antonescu-Turcu, Andrea; Ratarasarn, Kavita
There is growing evidence that demonstrates an important role for telemedicine technologies in enhancing healthcare delivery. A comprehensive sleep telemedicine protocol was implemented at the Veterans Administration Medical Center (VAMC), Milwaukee, WI, in 2008 in an effort to improve access to sleep specialty care. The telemedicine protocol relied heavily on sleep specialist interventions based on chart review (electronic consult [e-consult]). This was done in response to long wait time for sleep clinic visits as well as delayed sleep study appointments. Since 2008 all consults are screened by sleep service to determine the next step in intervention. Based on chart review, the following steps are undertaken: (1) eligibility for portable versus in-lab sleep study is determined, and a sleep study order is placed accordingly, (2) positive airway pressure (PAP) therapy is prescribed for confirmed sleep apnea, and (3) need for in-person evaluation in the sleep clinic is determined, and the visit is scheduled. This study summarizes the 5-year trend in various aspects of access to sleep care after implementation of sleep telemedicine protocol at the Milwaukee VAMC. This is a retrospective system efficiency study. The electronic medical record was interrogated 5 years after starting the sleep telemedicine protocol to study annual trends in the following outcomes: (1) interval between sleep consult and prescription of PAP equipment, (2) total sleep consults, and (3) sleep clinic wait time. Two part-time sleep physicians provided sleep-related care at the Milwaukee VAMC between 2008 and 2012. During this period, the interval between sleep consult and PAP prescription decreased from ≥60 days to ≤7 days. This occurred in spite of an increase in total sleep consults and sleep studies. There was also a significant increase in data downloads, indicating overall improved follow-up. There was no change in clinic wait time of ≥60 days. Implementation of a sleep telemedicine
Full Text Available Michael Linden,1,2 Marie Dietz,1 Christian Veauthier,3 Ingo Fietze3 1Research Group Psychosomatic Rehabilitation, Charité University Medicine Berlin, 2Department of Psychosomatic Medicine, Rehabilitation Centre Seehof, Teltow, 3Interdisciplinary Center of Sleep Medicine, Charité University Medicine Berlin, Berlin, Germany Objective: To elucidate the relationship between subjective complaints and polysomnographical parameters in psychosomatic patients.Method: A convenience sample of patients from a psychosomatic inpatient unit were classified according to the Pittsburgh Sleep Quality Index (PSQI as very poor sleepers (PSQI >10, n=80 and good sleepers (PSQI <6, n=19. They then underwent a polysomnography and in the morning rated their previous night’s sleep using a published protocol (Deutschen Gesellschaft für Schlafforschung und Schlafmedizin morning protocol [MP].Results: In the polysomnography, significant differences were found between very poor and good sleepers according to the PSQI with respect to sleep efficiency and time awake after sleep onset. When comparing objective PSG and subjective MP, the polysomnographical sleep onset latency was significantly positively correlated with the corresponding parameters of the MP: the subjective sleep onset latency in minutes and the subjective evaluation of sleep onset latency (very short, short, normal, long, very long were positively correlated with the sleep latency measured by polysomnography. The polysomnographical time awake after sleep onset (in minutes was positively correlated with the subjective time awake after sleep onset (in minutes, evaluation of time awake after sleep onset (seldom, normal often, and subjective restfulness. The polysomnographical total sleep time (TST was positively correlated with the subjective TST. Conversely, the polysomnographical TST was negatively correlated with the evaluation of TST (high polysomnographical TST was correlated with the subjective
Kong, Il Gyu; Lee, Hyo-Jeong; Kim, So Young; Sim, Songyong; Choi, Hyo Geun
Low physical activity, long leisure sitting time, and short sleep time are risk factors for obesity, but the association with study sitting time is unknown. The objective of this study was to evaluate the association between these factors and obesity.We analyzed the association between physical activity, study sitting time, leisure sitting time, and sleep time and subject weight (underweight, healthy weight, overweight, and obese), using data from a large population-based survey, the 2013 Korea Youth Risk Behavior Web-based Survey. Data from 53,769 participants were analyzed using multinomial logistic regression analyses with complex sampling. Age, sex, region of residence, economic level, smoking, stress level, physical activity, sitting time for study, sitting time for leisure, and sleep time were adjusted as the confounders.Low physical activity (adjusted odds ratios [AORs] = 1.03, 1.12) and long leisure sitting time (AORs = 1.15, 1.32) were positively associated with overweight and obese. Low physical activity (AOR = 1.33) and long leisure sitting time (AOR = 1.12) were also associated with underweight. Study sitting time was negatively associated with underweight (AOR = 0.86) but was unrelated to overweight (AOR = 0.97, 95% confidence interval [CI] = 0.91-1.03) and obese (AOR = 0.94, 95% CI = 0.84-1.04). Sleep time (physical activity, decreasing leisure sitting time, and obtaining sufficient sleep would be beneficial in maintaining a healthy weight. However, study sitting time was not associated with overweight or obese.
Casida, Jesus M; Davis, Jean E; Zalewski, Aaron; Yang, James J
To explore the context and the influence of night-time care routine interactions (NCRIs) on night-time sleep effectiveness (NSE) and daytime sleepiness (DSS) of patients in the cardiac surgery critical-care and progressive-care units of a hospital. There exists a paucity of empirical data regarding the influence of NCRIs on sleep and associated outcomes in hospitalised adult cardiac surgery patients. An exploratory repeated-measures research design was employed on the data provided by 38 elective cardiac surgery patients (mean age 60.0 ± 15.9 years). NCRI forms were completed by the bedside nurses and patients completed a 9-item Visual Analogue Sleep Scale (100-mm horizontal lines measuring NSE and DSS variables). All data were collected during postoperative nights/days (PON/POD) 1 through 5 and analysed with IBM SPSS software. Patient assessment, medication administration and laboratory/diagnostic procedures were the top three NCRIs reported between midnight and 6:00 a.m. During PON/POD 1 through 5, the respective mean NSE and DSS scores ranged from 52.9 ± 17.2 to 57.8 ± 13.5 and from 27.0 ± 22.6 to 45.6 ± 16.5. Repeated-measures ANOVA showed significant changes in DSS scores (p .05). Finally, of 8 NCRIs, only 1 (postoperative exercises) was significantly related to sleep variables (r > .40, p disruptions and daytime sleepiness in adult cardiac surgery. Worldwide, acute and critical-care nurses are well positioned to lead initiatives aimed at improving sleep and clinical outcomes in cardiac surgery. © 2018 John Wiley & Sons Ltd.
Biggs, Sarah N; Meltzer, Lisa J; Tapia, Ignacio E; Traylor, Joel; Nixon, Gillian M; Horne, Rosemary S C; Doyle, Lex W; Asztalos, Elizabeth; Mindell, Jodi A; Marcus, Carole L
To compare sleep/wake patterns in children born preterm in Australia vs Canada and determine cultural differences in the relationship between parental perception of sleep and actual sleep behaviors. Australian and Canadian children born preterm were recruited from the Caffeine for Apnea of Prematurity trial (n = 188, 5-12 y) and underwent 14 days actigraphy monitoring. Parents completed the National Sleep Foundation 2004 Sleep in America questionnaire. Cross-cultural differences in sleep characteristics assessed by actigraphy and parent-reported questionnaire were examined. Correlational analyses determined the associations between parental perceptions of child sleep need and sleep behavior. Actigraphy showed preterm children obtained, on average, 8 h sleep/night, one hour less than population recommendations for their age. There was no difference in total sleep time (TST) between Australian and Canadian cohorts; however, bed and wake times were earlier in Australian children. Bedtimes and TST varied by 60 minutes from night to night in both cohorts. Parent-reported child TST on the National Sleep Foundation questionnaire was 90 minutes longer than recorded by actigraphy. Both bedtime and TST on weekdays and weekends were related to parental perception of child sleep need in the Australian cohort. Only TST on weekdays was related to parental perception of child sleep need in the Canadian cohort. This study suggests that short sleep duration and irregular sleep schedules are common in children born preterm. Cultural differences in the association between parental perception of child sleep need and actual sleep behaviors provide important targets for future sleep health education. © 2016 American Academy of Sleep Medicine.
Full Text Available To test the independent and interactive associations of physical activity (PA and screen time (ST with self-reported mental health and sleep quality among Chinese college students.Data were collected in October, 2013. The gender, age, residential background, body mass index (BMI, perceived family economy and perceived study burden were obtained from a total of 4747 college students (41.6% males and 58.4% females. The outcomes were self-reported PA status, ST, anxiety, depression, psychopathological symptoms and sleep quality. Analyses were conducted with logistic regression models.Overall, 16.3%, 15.9% and 17.3% of the students had psychological problems, such as anxiety, depression and psychopathological symptoms, respectively. The prevalence of poor sleep quality was 9.8%. High ST was significantly positively associated with anxiety (OR=1.38, 95%CI: 1.15-1.65, depression (OR=1.76, 95%CI: 1.47-2.09, psychopathological symptoms (OR=1.69, 95%CI: 1.43-2.01 and poor sleep quality (OR=1.32, 95%CI: 1.06-1.65. High PA was insignificantly negatively associated with anxiety, depression, psychopathological symptoms and poor sleep. Low PA and high ST were independently and interactively associated with increased risks of mental health problems and poor sleep quality (p<0.05 for all.Interventions are needed to reduce ST and increase PA in the lifestyles of young people. Future research should develop and measure the impacts of interventions and their potential consequences on sleep, health, and well being.
A 49 years old man, known case of bronchial asthma for 43 years, with history of frequent asthmatic attacks, usually responding to double dose of intravenous Aminophylline and double dose of Hydrocortisone was received at medical emergency care unit at midnight with night-time asthma attack. The attack did not settle ...
Zohal, Mohammadali; Ghorbani, Azam; Esmailzadehha, Neda; Ziaee, Amir; Mohammadi, Zahrasadat
The aim of this study was to determine the association of sleep quality and sleep quantity with metabolic syndrome in Qazvin, Iran. this cross sectional study was conducted in 1079 residents of Qazvin selected by multistage cluster random sampling method in 2011. Metabolic syndrome was defined according to the criteria proposed by the national cholesterol education program third Adult treatment panel. Sleep was assessed using the Pittsburgh sleep quality index (PSQI). A logistic regression analysis was used to examine the association of sleep status and metabolic syndrome. Mean age was 40.08±10.33years. Of 1079, 578 (52.2%) were female, and 30.6% had metabolic syndrome. The total global PSQI score in the subjects with metabolic syndrome was significantly higher than subjects without metabolic syndrome (6.30±3.20 vs. 5.83±2.76, P=0.013). In logistic regression analysis, sleep disturbances was associated with 1.388 fold increased risk of metabolic syndrome after adjustment for age, gender, and body mass index. Sleep disturbances component was a predictor of metabolic syndrome in the present study. More longitudinal studies are necessary to understand the association of sleep quality and its components with metabolic syndrome. Copyright © 2017 Diabetes India. Published by Elsevier Ltd. All rights reserved.
Yan, Jin H
Motor skill acquisition occurs while practicing (on-line) and when asleep or awake (off-line). However, developmental questions still remain about whether children of various ages benefit similarly or differentially from night- and day-time sleeping. The likely circadian effects (time-of-day) and the possible between-test-interference (order effects) associated with children's off-line motor learning are currently unknown. Therefore, this study examines the contributions of over-night sleeping and mid-day napping to procedural skill learning. One hundred and eight children were instructed to practice a finger sequence task using computer keyboards. After an equivalent 11-h interval in one of the three states (sleep, nap, wakefulness), children performed the same sequence in retention tests and a novel sequence in transfer tests. Changes in the movement time and sequence accuracy were evaluated between ages (6-7, 8-9, 10-11years) during practice, and from skill training to retrievals across three states. Results suggest that night-time sleeping and day-time napping improved the tapping speed, especially for the 6-year-olds. The circadian factor did not affect off-line motor learning in children. The interference between the two counter-balanced retrieval tests was not found for the off-line motor learning. This research offers possible evidence about the age-related motor learning characteristics in children and a potential means for enhancing developmental motor skills. The dynamics between age, experience, memory formation, and the theoretical implications of motor skill acquisition are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.
Balling, Mie; Holmberg, Teresa; Petersen, Christina B
AIMS: This study aimed to test the hypotheses that a high total sitting time and vigorous physical activity in leisure time increase the risk of low back pain and herniated lumbar disc disease. METHODS: A total of 76,438 adults answered questions regarding their total sitting time and physical...... activity during leisure time in the Danish Health Examination Survey 2007-2008. Information on low back pain diagnoses up to 10 September 2015 was obtained from The National Patient Register. The mean follow-up time was 7.4 years. Data were analysed using Cox regression analysis with adjustment...... disc disease. However, moderate or vigorous physical activity, as compared to light physical activity, was associated with increased risk of low back pain (HR = 1.16, 95% CI: 1.03-1.30 and HR = 1.45, 95% CI: 1.15-1.83). Moderate, but not vigorous physical activity was associated with increased risk...
Ocampo-Garcés, Adrián; Hernández, Felipe; Palacios, Adrian G.
Study Objectives: To determine rapid eye movement (REM) sleep phase preference in a crepuscular mammal (Octodon degus) by challenging the specific REM sleep homeostatic response during the diurnal and nocturnal anticrepuscular rest phases. Design: We have investigated REM sleep rebound, recovery, and documented REM sleep propensity measures during and after diurnal and nocturnal selective REM sleep deprivations. Subjects: Nine male wild-captured O. degus prepared for polysomnographic recordings Interventions: Animals were recorded during four consecutive baseline and two separate diurnal or nocturnal deprivation days, under a 12:12 light-dark schedule. Three-h selective REM sleep deprivations were performed, starting at midday (zeitgeber time 6) or midnight (zeitgeber time 18). Measurements and Results: Diurnal and nocturnal REM sleep deprivations provoked equivalent amounts of REM sleep debt, but a consistent REM sleep rebound was found only after nocturnal deprivation. The nocturnal rebound was characterized by a complete recovery of REM sleep associated with an augment in REM/total sleep time ratio and enhancement in REM sleep episode consolidation. Conclusions: Our results support the notion that the circadian system actively promotes REM sleep. We propose that the sleep-wake cycle of O. degus is modulated by a chorus of circadian oscillators with a bimodal crepuscular modulation of arousal and a unimodal promotion of nocturnal REM sleep. Citation: Ocampo-Garcés A; Hernández F; Palacios AG. REM sleep phase preference in the crepuscular Octodon degus assessed by selective REM sleep deprivation. SLEEP 2013;36(8):1247-1256. PMID:23904685
Martin-Ordas, Gema; Call, Josep
Following encoding, memory remains temporarily vulnerable to disruption. Consolidation refers to offline time-dependent processes that continue after encoding and stabilize, transform or enhance the memory trace. Memory consolidation resulting from sleep has been reported for declarative and non-declarative memories in humans. We first investigated the temporal course of memory retrieval in chimpanzees, bonobos and orangutans. We found that the amount of retrieved information was time dependent: apes' performance degraded after 1 and 2 h, stabilized after 4 h, started to increase after 8 and 12 h and fully recovered after 24 h. Second, we show that although memories during wakefulness were highly vulnerable to interference from events similar to those witnessed during the original encoding event, an intervening period of sleep not only stabilized apes' memories into more permanent ones but also protected them against interference.
Tuck Seng Cheng
Full Text Available Plasma 25-hydroxyvitamin D (25OHD deficiency, poor sleep quality, and night-time eating, have been independently associated with adverse pregnancy outcomes, but their inter-relationships are yet to be evaluated. We aimed to investigate the associations between maternal plasma 25OHD status and sleep quality and circadian eating patterns during pregnancy. Data on pregnant women (n = 890 from a prospective cohort (Growing Up in Singapore Towards healthy Outcomes were analyzed. Plasma 25OHD concentration was measured, while the Pittsburgh sleep quality index (PSQI and 24-h dietary recall were administered to women at 26–28 weeks’ gestation. Plasma 25OHD status was defined as sufficient (>75 nmol/L, insufficient (50–75 nmol/L, or deficient (<50 nmol/L. Poor sleep quality was defined by a total global PSQI score >5. Predominantly day-time (pDT and predominantly night-time (pNT were defined according to consumption of greater proportion of calories (i.e., >50% from 07:00–18:59 and from 19:00–06:59, respectively. After adjustment for confounders, women with plasma 25OHD deficiency had higher odds of poor sleep quality (odds ratio (OR 3.49; 95% confidence interval (CI 1.84–6.63 and pNT eating (OR: 1.85; 95% CI 1.00–3.41 than those who were 25OHD sufficient. Our findings show the association of maternal plasma 25OHD deficiency with poor sleep quality and pNT eating at mid-pregnancy.
Brady, M.E.; Hayton, W.L.
The duration of the loss of righting reflex (sleeping time) was determined after intraperitoneal administration of 100 mg(/kg hexobarbital to adult male Sprague--Dawley rats that were exposed to 60 Co γ radiation or sham irradiated. No difference between irradiated and control animals was detected at 1, 3, 5, and 7 days after 850 R. Also, no difference between irradiated and control animals was detected at 5 days after 1000 or 1400 R
Arthur, Kimberly Ann
In previous work with mouse lines selected for resistance (R) and susceptibility (S) to fescue toxicosis, R mice had higher activities of Phase II liver enzymes glutathione S-transferase and uridine diphosphate glucuronosyl-transferase than S mice. Objectives of this study were: 1. to determine whether selection for toxicosis response had also caused divergence between lines in hepatic Phase I enzyme activity (as assessed by sleep time following sodium pentobarbital anesthesia), 2. to determi...
The total lactic acid bacterial community involved in the spontaneous fermentation of malted cowpea fortified cereal weaning food was investigated by phenotypically and cultivation independent method. A total of 74 out of the isolated 178 strains were Lactobacillus plantarum, 32 were Pediococcus acidilactici and over 60% ...
Maski, Kiran; Holbrook, Hannah; Manoach, Dara; Hanson, Ellen; Kapur, Kush; Stickgold, Robert
Examine the role of sleep in the consolidation of declarative memory in children with autism spectrum disorder (ASD). Case-control study. Home-based study with sleep and wake conditions. Twenty-two participants with ASD and 20 control participants between 9 and 16 y of age. Participants were trained to criterion on a spatial declarative memory task and then given a cued recall test. Retest occurred after a period of daytime wake (Wake) or a night of sleep (Sleep) with home-based polysomnography; Wake and Sleep conditions were counterbalanced. Children with ASD had poorer sleep efficiency than controls, but other sleep macroarchitectural and microarchitectural measures were comparable after controlling for age and medication use. Both groups demonstrated better memory consolidation across Sleep than Wake, although participants with ASD had poorer overall memory consolidation than controls. There was no interaction between group and condition. The change in performance across sleep, independent of medication and age, showed no significant relationships with any specific sleep parameters other than total sleep time and showed a trend toward less forgetting in the control group. This study shows that despite their more disturbed sleep quality, children with autism spectrum disorder (ASD) still demonstrate more stable memory consolidation across sleep than in wake conditions. The findings support the importance of sleep for stabilizing memory in children with and without neurodevelopmental disabilities. Our results suggest that improving sleep quality in children with ASD could have direct benefits to improving their overall cognitive functioning. © 2015 Associated Professional Sleep Societies, LLC.
The Sleep Sleeping Patch is a new kind of external patch based on modern sleep medicine research achievements, which uses the internationally advanced transdermal therapeutic system (TTS). The Sleep Sleeping Patch transmits natural sleep inducers such as peppermint and liquorice extracts and melatonin through the skin to induce sleep. Clinical research proves that the Sleep Sleeping Patch can effectively improve insomnia and the quality of sleep. Highly effective: With the modern TTS therapy,
Brunet, Jean-François; Dagenais, Dominique; Therrien, Marc; Gartenberg, Daniel; Forest, Geneviève
Despite its high sensitivity and validity in the context of sleep loss, the Psychomotor Vigilance Test (PVT) could be improved. The aim of the present study was to validate a new smartphone PVT-type application called sleep-2-Peak (s2P) by determining its ability to assess fatigue-related changes in alertness in a context of extended wakefulness. Short 3-min versions of s2P and of the classic PVT were administered at every even hour during a 35-h total sleep deprivation protocol. In addition, subjective measures of sleepiness were collected. The outcomes on these tests were then compared using Pearson product-moment correlations, t tests, and repeated measures within-groups analyses of variance. The results showed that both tests significantly correlated on all outcome variables, that both significantly distinguished between the alert and sleepy states in the same individual, and that both varied similarly through the sleep deprivation protocol as sleep loss accumulated. All outcome variables on both tests also correlated significantly with the subjective measures of sleepiness. These results suggest that a 3-min version of s2P is a valid tool for differentiating alert from sleepy states and is as sensitive as the PVT for tracking fatigue-related changes during extended wakefulness and sleep loss. Unlike the PVT, s2P does not provide feedback to subjects on each trial. We discuss how this feature of s2P raises the possibility that the performance results measured by s2P could be less impacted by motivational confounds, giving this tool added value in particular clinical and/or research settings.
Wagner, David T; Barnes, Christopher M; Lim, Vivien K G; Ferris, D Lance
The Internet is a powerful tool that has changed the way people work. However, the ubiquity of the Internet has led to a new workplace threat to productivity-cyberloafing. Building on the ego depletion model of self-regulation, we examine how lost and low-quality sleep influence employee cyberloafing behaviors and how individual differences in conscientiousness moderate these effects. We also demonstrate that the shift to Daylight Saving Time (DST) results in a dramatic increase in cyberloafing behavior at the national level. We first tested the DST-cyberloafing relation through a national quasi-experiment, then directly tested the relation between sleep and cyberloafing in a closely controlled laboratory setting. We discuss the implications of our findings for theory, practice, and future research.
Bowers, Jennifer M; Moyer, Anne
Research conducted over the past three decades finds that many children and adolescents do not meet recommended sleep guidelines. Lack of sleep is a predictor of a number of consequences, including issues at school such as sleepiness and tardiness. Considering the severity of this public health issue, it is essential to understand more about the factors that may compromise children's and adolescents' sleep. This meta-analysis examined the effects of school start time (SST) on sleep duration of students by aggregating the results of five longitudinal studies and 15 cross-sectional comparison group studies. Results indicated that later starting school times are associated with longer sleep durations. Additionally, later start times were associated with less daytime sleepiness (7 studies) and tardiness to school (3 studies). However, methodological considerations, such as a need for more longitudinal primary research, lead to a cautious interpretation. Overall, this systematic analysis of SST studies suggests that delaying SST is associated with benefits for students' sleep and, thus, their general well-being. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.
Kruger, Jean-Leigh; Gravett, Nadine; Bhagwandin, Adhil; Bennett, Nigel C; Archer, Elizabeth K; Manger, Paul R
The Cape mole rat Georychus capensis is a solitary subterranean rodent found in the western and southern Cape of South Africa. This approximately 200-gram bathyergid rodent shows a nocturnal circadian rhythm, but sleep in this species is yet to be investigated. Using telemetric recordings of the electroencephalogram (EEG) and electromyogram (EMG) in conjunction with video recordings, we were able to show that the Cape mole rat, like all other rodents, has sleep periods composed of both rapid eye movement (REM) and slow-wave (non-REM) sleep. These mole rats spent on average 15.4 h awake, 7.1 h in non-REM sleep and 1.5 h in REM sleep each day. Cape mole rats sleep substantially less than other similarly sized terrestrial rodents but have a similar percentage of total sleep time occupied by REM sleep. In addition, the duration of both non-REM and REM sleep episodes was markedly shorter in the Cape mole rat than has been observed in terrestrial rodents. Interestingly, these features (total sleep time and episode duration) are similar to those observed in another subterranean bathyergid mole rat, i.e. Fukomys mechowii. Thus, there appears to be a bathyergid type of sleep amongst the rodents that may be related to their environment and the effect of this on their circadian rhythm. Investigating further species of bathyergid mole rats may fully define the emerging picture of sleep in these subterranean African rodents. © 2016 S. Karger AG, Basel.
Chambon, Stanislas; Galtier, Mathieu; Arnal, Pierrick; Wainrib, Gilles; Gramfort, Alexandre
Sleep stage classification constitutes an important preliminary exam in the diagnosis of sleep disorders. It is traditionally performed by a sleep expert who assigns to each 30s of signal a sleep stage, based on the visual inspection of signals such as electroencephalograms (EEG), electrooculograms (EOG), electrocardiograms (ECG) and electromyograms (EMG). We introduce here the first deep learning approach for sleep stage classification that learns end-to-end without computing spectrograms or...
Full Text Available Under sleep loss, vigilance is reduced and attentional failures emerge progressively. It becomes difficult to maintain stable performance over time, leading to growing performance variability (i.e. state instability in an individual and among subjects. Task duration plays a major role in the maintenance of stable vigilance levels, such that the longer the task, the more likely state instability will be observed. Vulnerability to sleep-loss-dependent performance decrements is highly individual and is also modulated by a polymorphism in the human clock gene PERIOD3 (PER3. By combining two different protocols, we manipulated sleep-wake history by once extending wakefulness for 40 h (high sleep pressure condition and once by imposing a short sleep-wake cycle by alternating 160 min of wakefulness and 80 min naps (low sleep pressure condition in a within-subject design. We observed that homozygous carriers of the long repeat allele of PER3 (PER35/5 experienced a greater time-on-task dependent performance decrement (i.e., a steeper increase in the number of lapses in the Psychomotor Vigilance Task compared to the carriers of the short repeat allele (PER34/4. These genotype-dependent effects disappeared under low sleep pressure conditions, and neither motivation, nor perceived effort accounted for these differences. Our data thus suggest that greater sleep-loss related attentional vulnerability based on the PER3 polymorphism is mirrored by a greater state instability under extended wakefulness in the short compared to the long allele carriers. Our results undermine the importance of time-on-task related aspects when investigating inter-individual differences in sleep loss-induced behavioural vulnerability.
Basner, Mathias; Rubinstein, Joshua; Fomberstein, Kenneth M; Coble, Matthew C; Ecker, Adrian; Avinash, Deepa; Dinges, David F
To investigate the effects of night work and sleep loss on a simulated luggage screening task (SLST) that mimicked the x-ray system used by airport luggage screeners. We developed more than 5,800 unique simulated x-ray images of luggage organized into 31 stimulus sets of 200 bags each. 25% of each set contained either a gun or a knife with low or high target difficulty. The 200-bag stimuli sets were then run on software that simulates an x-ray screening system (SLST). Signal detection analysis was used to obtain measures of hit rate (HR), false alarm rate (FAR), threat detection accuracy (A'), and response bias (B"(D)). Experimental laboratory study 24 healthy nonprofessional volunteers (13 women, mean age +/- SD = 29.9 +/- 6.5 years). Subjects performed the SLST every 2 h during a 5-day period that included a 35 h period of wakefulness that extended to night work and then another day work period after the night without sleep. Threat detection accuracy A' decreased significantly (P work, while both A' (P = 0.001) and HR decreased (P = 0.008) during day work following sleep loss. There were prominent time-on-task effects on response bias B"(D) (P= 0.002) and response latency (P = 0.004), but accuracy A' was unaffected. Both HR and FAR increased significantly with increasing study duration (both P work and sleep loss adversely affect the accuracy of detecting complex real world objects among high levels of background clutter. If the results can be replicated in professional screeners and real work environments, fatigue in luggage screening personnel may pose a threat for air traffic safety unless countermeasures for fatigue are deployed.
This review examines the biological background to the development of ideas on rapid eye movement sleep (REM sleep), so-called paradoxical sleep (PS), and its relation to dreaming. Aspects of the phenomenon which are discussed include physiological changes and their anatomical location, the effects of total and selective sleep deprivation in the human and animal, and REM sleep behavior disorder, the latter with its clinical manifestations in the human. Although dreaming also occurs in other sleep phases (non-REM or NREM sleep), in the human, there is a contingent relation between REM sleep and dreaming. Thus, REM is taken as a marker for dreaming and as REM is distributed ubiquitously throughout the mammalian class, it is suggested that other mammals also dream. It is suggested that the overall function of REM sleep/dreaming is more important than the content of the individual dream; its function is to place the dreamer protagonist/observer on the topographical world. This has importance for the developing infant who needs to develop a sense of self and separateness from the world which it requires to navigate and from which it is separated for long periods in sleep. Dreaming may also serve to maintain a sense of ‘I’ness or “self” in the adult, in whom a fragility of this faculty is revealed in neurological disorders.
Amanda L Gamble
Full Text Available INTRODUCTION: Electronic devices in the bedroom are broadly linked with poor sleep in adolescents. This study investigated whether there is a dose-response relationship between use of electronic devices (computers, cellphones, televisions and radios in bed prior to sleep and adolescent sleep patterns. METHODS: Adolescents aged 11-17 yrs (n = 1,184; 67.6% female completed an Australia-wide internet survey that examined sleep patterns, sleepiness, sleep disorders, the presence of electronic devices in the bedroom and frequency of use in bed at night. RESULTS: Over 70% of adolescents reported 2 or more electronic devices in their bedroom at night. Use of devices in bed a few nights per week or more was 46.8% cellphone, 38.5% computer, 23.2% TV, and 15.8% radio. Device use had dose-dependent associations with later sleep onset on weekdays (highest-dose computer adjOR = 3.75: 99% CI = 2.17-6.46; cellphone 2.29: 1.22-4.30 and weekends (computer 3.68: 2.14-6.32; cellphone 3.24: 1.70-6.19; TV 2.32: 1.30-4.14, and later waking on weekdays (computer 2.08: 1.25-3.44; TV 2.31: 1.33-4.02 and weekends (computer 1.99: 1.21-3.26; cellphone 2.33: 1.33-4.08; TV 2.04: 1.18-3.55. Only 'almost every night' computer use (: 2.43: 1.45-4.08 was associated with short weekday sleep duration, and only 'almost every night' cellphone use (2.23: 1.26-3.94 was associated with wake lag (waking later on weekends. CONCLUSIONS: Use of computers, cell-phones and televisions at higher doses was associated with delayed sleep/wake schedules and wake lag, potentially impairing health and educational outcomes.
Brinkman, W.M.; Buzink, S.N.; Alevizos, L.; De Hingh, I.H.J.T.; Jakimowicz, J.J.
The benefits of criterion-based laparoscopic training over time-oriented training are unclear. The purpose of this study is to compare these types of training based on training outcome and time efficiency. Methods During four training sessions within 1 week (one session per day) 34 medical interns
Paterson, Jessica L; Reynolds, Amy C; Ferguson, Sally A; Dawson, Drew
Obsessive-compulsive disorder (OCD) is a chronic mental illness that can have a debilitating effect on daily functioning. A body of research reveals altered sleep behaviour in OCD sufferers; however, findings are inconsistent and there is no consensus on the nature of this relationship. Understanding sleep disturbance in OCD is of critical importance given the known negative consequences of disturbed sleep for mood and emotional wellbeing. A systematic literature search was conducted of five databases for studies assessing sleep in adults diagnosed with OCD. Fourteen studies met inclusion criteria and qualitative data analysis methods were used to identify common themes. There was some evidence of reduced total sleep time and sleep efficiency in OCD patients. Many of the sleep disturbances noted were characteristic of depression. However, some OCD sufferers displayed delayed sleep onset and offset and an increased prevalence of delayed sleep phase disorder (DSPD). Severe OCD symptoms were consistently associated with greater sleep disturbance. While the sleep of OCD patients has not been a major focus to date, the existing literature suggests that addressing sleep disturbance in OCD patients may ensure a holistic approach to treatment, enhance treatment efficacy, mitigate relapse and protect against the onset of co-morbid psychiatric illnesses. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.
Lazaratou, E; Dikeos, D; Anagnostopoulos, D; Soldatos, C
The evaluation of sleep habits and sleep related problems in high school adolescent students in the Athens area and the assessment of these problems' relation to demographic and other variables was investigated by the Athens Insomnia Scale - 5 item version (AIS-5), which was administered to 713 adolescent Senior High School students in the Greater Athens Area. Data such as age, sex, school records, and time spent per week in school-related and extracurricular activities were collected. The sample's mean sleep duration was 7,5 hours, mean bedtime 12:20 am and wake-up time 7:15 am. Total sleep time was not affected by gender, but was influenced by time spent in various activities. Sleep complaints were related to delayed sleep, onset latency and insufficient total duration of sleep. Girls complained more than boys, while correlations showed that students with lower academic per formance and those in second grade were more likely to have higher AIS-5 scores. The results show that sleep time of high school students is dependent on practical matters such as school schedule and other activities, while sleep complaints are related to female gender, bad school performance as well as to the second grade. The difference between actual sleep time and sleep complaints should be considered when studying the sleep of adolescents.
Shearer, William T.; Reuben, James M.; Lee, Bang-Ning; Mullington, Janet; Price, Nicholas; Dinges, David F.
Plasma levels of IL-6 and TNF-α are elevated in individuals who are deprived of sleep. TNF-α regulates expression of its soluble receptors, sTNF-αRI and sTNF-αRII. Sleep deprivation (SD) also increases extracellular adenosine that induces sedation and sleep. An antagonist of adenosine, caffeine, raises exogenous adenosine levels, stimulates the expression of IL-6 and inhibits the release of TNF-α. Our objective was to determine the effect of total SD (TSD) or partial SD (PSD) on the levels of these sleep regulatory molecules in volunteers who experienced SD with or without the consumption of caffeine. Plasma levels of IL-6, sTNF-αRI and sTNF-αRII were assayed by ELISA in samples collected at 90-min intervals from each subject over an 88-hour period. The results were analyzed by the repeated measures ANOVA. Whereas only TSD significantly increased sTNF-αRI over time, caffeine suppressed both sTNF-α receptors in TSD and PSD subjects. The selective increase in the expression of sTNF-αRI and not sTNF-αRII in subjects experiencing TSD with caffeine compared with others experiencing PSD with caffeine has not been previously reported. Moreover, caffeine significantly increased IL-6 in TSD subjects compared with those who did not receive caffeine. However, subjects who were permitted intermittent naps (PSD) ablated the effects of caffeine and reduced their level of IL-6 to that of the TSD group. These data further lend support to the hypothesis that the sTNF-αRI and not the sTNF-αRII plays a significant role in sleep regulation by TNF-α. .
Kung, Pei-Ying; Chou, Kuei-Ru; Lin, Kuan-Chia; Hsu, Hsin-Wei; Chung, Min-Huey
Depression has become a severe global health problem, and sleeping difficulties are typically associated with depression. The purpose of this study was to investigate the relationships among subjective sleep quality, objective sleep quality, and the sleep hygiene practices of hospitalized patients with major depressive disorder. Daily sleep logs and actigraphy were used to obtain subjective and objective sleep data. Thirty patients were recruited from a regional teaching hospital in Taipei and completed the Hamilton Rating Scale for Depression and the Sleep Hygiene Practice Scale. Significant differences were found between subjective and objective sleep data in patients with major depressive disorder (MDD). For patients with more severe depression, subjective measurements obtained using sleep logs, such as total sleep time and sleep efficiency, were significantly lower than those obtained using actigraphy by controlling for demographics. The results regarding the differences between subjective and objective sleep data can be a reference for care providers when comforting depression patients who complain of sleep disturbance. Copyright © 2014 Elsevier Inc. All rights reserved.
Dworak, Markus; Kim, Tae; Mccarley, Robert W; Basheer, Radhika
Sleep has been postulated to promote brain energy restoration. It is as yet unknown if increasing the energy availability within the brain reduces sleep need. The guanidine amino acid creatine (Cr) is a well-known energy booster in cellular energy homeostasis. Oral Cr-monohydrate supplementation (CS) increases exercise performance and has been shown to have substantial effects on cognitive performance, neuroprotection and circadian rhythms. The effect of CS on cellular high-energy molecules and sleep-wake behaviour is unclear. Here, we examined the sleep-wake behaviour and brain energy metabolism before and after 4-week-long oral administration of CS in the rat. CS decreased total sleep time and non-rapid eye movement (NREM) sleep significantly during the light (inactive) but not during the dark (active) period. NREM sleep and NREM delta activity were decreased significantly in CS rats after 6 h of sleep deprivation. Biochemical analysis of brain energy metabolites showed a tendency to increase in phosphocreatine after CS, while cellular adenosine triphosphate (ATP) level decreased. Microdialysis analysis showed that the sleep deprivation-induced increase in extracellular adenosine was attenuated after CS. These results suggest that CS reduces sleep need and homeostatic sleep pressure in rats, thereby indicating its potential in the treatment of sleep-related disorders. © 2017 European Sleep Research Society.
Taylor, Daniel J.; Vatthauer, Karlyn E.; Bramoweth, Adam D.; Ruggero, Camilo; Roane, Brandy
Few studies have looked at the predictability of academic performance (i.e., cumulative grade point average [GPA]) using sleep when common nonsleep predictors of academic performance are included. The present project studied psychological, demographic, educational, and sleep risk factors of decreased academic performance in college undergraduates. Subjects (N = 867) completed a questionnaire packet and sleep diary. It was hypothesized that low total sleep time (TST), increased sleep onset lat...
Schlager, R.J.; Wilson, K.G.; Sappey, A.D.
ADA Technologies, Inc., is developing a continuous emissions monitoring system that measures the concentrations of mercury in flue gas. Mercury is emitted as an air pollutant from a number of industrial processes. The largest contributors of these emissions are coal and oil combustion, municipal waste combustion, medical waste combustion, and the thermal treatment of hazardous materials. It is difficult, time consuming, and expensive to measure mercury emissions using current testing methods. Part of the difficulty lies in the fact that mercury is emitted from sources in several different forms, such as elemental mercury and mercuric chloride. The ADA analyzer measures these emissions in real time, thus providing a number of advantages over existing test methods: (1) it will provide a real-time measure of emission rates, (2) it will assure facility operators, regulators, and the public that emissions control systems are working at peak efficiency, and (3) it will provide information as to the nature of the emitted mercury (elemental mercury or speciated compounds). This update presents an overview of the CEM and describes features of key components of the monitoring system--the mercury detector, a mercury species converter, and the analyzer calibration system
Schlager, R.J.; Wilson, K.G.; Sappey, A.D. [ADA Technologies, Inc., Englewood, CO (United States)
ADA Technologies, Inc., is developing a continuous emissions monitoring system that measures the concentrations of mercury in flue gas. Mercury is emitted as an air pollutant from a number of industrial processes. The largest contributors of these emissions are coal and oil combustion, municipal waste combustion, medical waste combustion, and the thermal treatment of hazardous materials. It is difficult, time consuming, and expensive to measure mercury emissions using current testing methods. Part of the difficulty lies in the fact that mercury is emitted from sources in several different forms, such as elemental mercury and mercuric chloride. The ADA analyzer measures these emissions in real time, thus providing a number of advantages over existing test methods: (1) it will provide a real-time measure of emission rates, (2) it will assure facility operators, regulators, and the public that emissions control systems are working at peak efficiency, and (3) it will provide information as to the nature of the emitted mercury (elemental mercury or speciated compounds). This update presents an overview of the CEM and describes features of key components of the monitoring system--the mercury detector, a mercury species converter, and the analyzer calibration system.
Silvio Calgaro Neto
Full Text Available This article is dedicated to explore the field of knowledge related to rural extension. In general, a three complementary perspective is used as theoretical strategy to present this epistemological study. The first perspective, seeks to accomplish a brief archeology of rural extension, identifying the remarkable historical passages. At the second, we look to some theoretical models through the modern epistemological platform. Finally, the third perspective, aims to present a methodological proposal that contemplate this epistemic characteristics, relating with the contemporary transformations observed in the knowledge construction and technological transference for a rural development. Keywords: Total institutions. University.
Brinkman, Willem M.; Buzink, Sonja N.; Alevizos, Leonidas; de Hingh, Ignace H. J. T.; Jakimowicz, Jack J.
Introduction The benefits of criterion-based laparoscopic training over time-oriented training are unclear. The purpose of this study is to compare these types of training based on training outcome and time efficiency. Methods During four training sessions within 1 week (one session per day) 34 medical interns (no laparoscopic experience) practiced on two basic tasks on the Simbionix LAP Mentor virtual-reality (VR) simulator: ‘clipping and grasping’ and ‘cutting’. Group C (criterion-based) (N...
Younes, Magdy; Kuna, Samuel T; Pack, Allan I; Walsh, James K; Kushida, Clete A; Staley, Bethany; Pien, Grace W
The American Academy of Sleep Medicine has published manuals for scoring polysomnograms that recommend time spent in non-rapid eye movement sleep stages (stage N1, N2, and N3 sleep) be reported. Given the well-established large interrater variability in scoring stage N1 and N3 sleep, we determined the range of time in stage N1 and N3 sleep scored by a large number of technologists when compared to reasonably estimated true values. Polysomnograms of 70 females were scored by 10 highly trained sleep technologists, two each from five different academic sleep laboratories. Range and confidence interval (CI = difference between the 5th and 95th percentiles) of the 10 times spent in stage N1 and N3 sleep assigned in each polysomnogram were determined. Average values of times spent in stage N1 and N3 sleep generated by the 10 technologists in each polysomnogram were considered representative of the true values for the individual polysomnogram. Accuracy of different technologists in estimating delta wave duration was determined by comparing their scores to digitally determined durations. The CI range of the ten N1 scores was 4 to 39 percent of total sleep time (% TST) in different polysomnograms (mean CI ± standard deviation = 11.1 ± 7.1 % TST). Corresponding range for N3 was 1 to 28 % TST (14.4 ± 6.1 % TST). For stage N1 and N3 sleep, very low or very high values were reported for virtually all polysomnograms by different technologists. Technologists varied widely in their assignment of stage N3 sleep, scoring that stage when the digitally determined time of delta waves ranged from 3 to 17 seconds. Manual scoring of non-rapid eye movement sleep stages is highly unreliable among highly trained, experienced technologists. Measures of sleep continuity and depth that are reliable and clinically relevant should be a focus of clinical research. © 2018 American Academy of Sleep Medicine
Kolla, Bhanu Prakash; Mansukhani, Subir; Mansukhani, Meghna P
Consumer sleep tracking devices such as fitness trackers and smartphone apps have become increasingly popular. These devices claim to measure the sleep duration of their users and in some cases purport to measure sleep quality and awaken users from light sleep, potentially improving overall sleep. Most of these devices appear to utilize data generated from in-built accelerometers to determine sleep parameters but the exact mechanisms and algorithms are proprietary. The growing literature comparing these devices against polysomnography/actigraphy shows that they tend to underestimate sleep disruptions and overestimate total sleep times and sleep efficiency in normal subjects. In this review, we evaluate the current literature comparing the accuracy of consumer sleep tracking devices against more conventional methods used to measure sleep duration and quality. We discuss the current technology that these devices utilize as well as summarize the value of these devices in clinical evaluations and their potential limitations.
Wolfson, Amy R; Carskadon, Mary A
The present paper reviews and critiques studies assessing the relation between sleep patterns, sleep quality, and school performance of adolescents attending middle school, high school, and/or college. The majority of studies relied on self-report, yet the researchers approached the question with different designs and measures. Specifically, studies looked at (1) sleep/wake patterns and usual grades, (2) school start time and phase preference in relation to sleep habits and quality and academic performance, and (3) sleep patterns and classroom performance (e.g., examination grades). The findings strongly indicate that self-reported shortened total sleep time, erratic sleep/wake schedules, late bed and rise times, and poor sleep quality are negatively associated with academic performance for adolescents from middle school through the college years. Limitations of the current published studies are also discussed in detail in this review.
Shakhlevich, N.V.; Hoogeveen, J.A.; Pinedo, M.L.
We study the special case of the m machine flow shop problem in which the processing time of each operation of job j is equal to pj; this variant of the flow shop problem is known as the proportionate flow shop problem. We show that for any number of machines and for any regular performance
Palchykova, S.; Tobler, I.
It is now well known that daily torpor induces a sleep deficit. Djungarian hamsters emerging from this hypometabolic state spend most of the time in sleep. This sleep is characterized by high initial values of EEG slow-wave activity (SWA) that monotonically decline during recovery sleep. These features resemble the changes seen in numerous species during recovery after prolonged wakefulness or sleep deprivation (SD). When hamsters are totally or partially sleep deprived immediately after emerging from torpor, an additional increase in SWA can be induced. It has been therefore postulated, that these slow- waves are homeostatically regulated, as predicted by the two-process model of sleep regulation, and that during daily torpor a sleep deficit is accumulated as it is during prolonged waking. The predominance of SWA in the frontal EEG observed both after SD and daily torpor provides further evidence for the similarity of these conditions. It has been shown in several animal and human studies that sleep can enhance memory consolidation, and that SD leads to memory impairment. Preliminary data obtained in the Djungarian hamster showed that both SD and daily torpor result in object recognition deficits. Thus, animals subjected to SD immediately after learning, or if they underwent an episode of daily torpor between learning and retention, displayed impaired recognition memory for complex object scenes. The investigation of daily torpor can reveal mechanisms that could have important implications for hypometabolic state induction in other mammalian species, including humans.
Wong, Shi Ngar; Halaki,Mark; Chow,Chin Moi
Shi Ngar Wong, Mark Halaki, Chin Moi ChowDiscipline of Exercise and Sport Science, University of Sydney, Sydney, NSW, AustraliaAbstract: The sleep–wake cycle is a process not only dictated by homeostatic and circadian factors but also by social and environmental influences. Thus, the total sleep time partly reflects sleep need, which is integral to the dynamics of sleep loss recovery. This study explored the nature of the observed oscillations in total sleep time in healthy adults u...
Polos, Peter G; Bhat, Sushanth; Gupta, Divya; O'Malley, Richard J; DeBari, Vincent A; Upadhyay, Hinesh; Chaudhry, Saqib; Nimma, Anitha; Pinto-Zipp, Genevieve; Chokroverty, Sudhansu
This cross-sectional study explored the extent and impact of mobile device-based Sleep Time-Related Information and Communication Technology (STRICT) use among American adolescents (N = 3139, 49.3% female, mean age = 13.3 years). Nearly 62% used STRICT after bedtime, 56.7% texted/tweeted/messaged in bed, and 20.8% awoke to texts. STRICT use was associated with insomnia, daytime sleepiness, eveningness, academic underperformance, later bedtimes and shorter sleep duration. Moderation analysis demonstrated that the association between STRICT use and insomnia increased with age, the association between STRICT use and daytime sleepiness decreased with age, and the association between STRICT use and shorter sleep duration decreased with age and was stronger in girls. Insomnia and daytime sleepiness partially mediated the relationship between STRICT use and academic underperformance. Our results illustrate the adverse interactions between adolescent STRICT use and sleep, with deleterious effects on daytime functioning. These worrisome findings suggest that placing reasonable limitations on adolescent STRICT use may be appropriate. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Tyagi, Shachi; Perera, Subashan; Clarkson, Becky D; Tadic, Stasa D; Resnick, Neil M
Nocturia is common and bothersome in older adults, especially those who are also incontinent. Since nocturnal polyuria is a major contributor, we examined factors associated with nocturnal polyuria in this population to identify those possibly amenable to intervention. We analyzed baseline data from 2 previously completed studies of urge urinary incontinence. The studies involved 284 women (mean age ± SD 72.9 ± 7.9 years) who also completed 3-day voiding diaries. Participants with a nocturnal polyuria index greater than 33% were categorized as having nocturnal polyuria (nocturnal polyuria index = nocturnal urinary volume per 24-hour urine volume). Associations between nocturnal polyuria and various demographic, clinical and sleep related parameters were determined. Overall 55% of the participants had nocturnal polyuria. Multivariable regression analysis revealed that age, body mass index, use of angiotensin converting enzyme inhibitor/angiotensin receptor blocker, time spent in bed and duration of first uninterrupted sleep were independent correlates of nocturnal polyuria. Participants with a larger nocturnal excretion reported a shorter duration of uninterrupted sleep before first awakening to void and worse sleep quality despite spending similar time in bed. Body mass index, use of angiotensin converting enzyme inhibitor/angiotensin receptor blockers, time in bed and duration of uninterrupted sleep before first awakening to void are independently associated with nocturnal polyuria in older women with urge urinary incontinence, and are potentially modifiable. These findings also confirm the association between sleep and nocturnal polyuria. Further studies should explore whether interventions to reduce nocturnal polyuria and/or increase the duration of uninterrupted sleep before first awakening to void would help to improve sleep quality in this population and thereby reduce or eliminate the need for sedative hypnotics. Copyright © 2017 American Urological
Seke Etet, Paul F; Palomba, Maria; Colavito, Valeria; Grassi-Zucconi, Gigliola; Bentivoglio, Marina; Bertini, Giuseppe
Human African trypanosomiasis (HAT), or sleeping sickness, is a severe disease caused by Trypanosoma brucei (T.b.). The disease hallmark is sleep alterations. Brain involvement in HAT is a crucial pathogenetic step for disease diagnosis and therapy. In this study, a rat model of African trypanosomiasis was used to assess changes of sleep-wake, rest-activity, and body temperature rhythms in the time window previously shown as crucial for brain parenchyma invasion by T.b. to determine potential biomarkers of this event. Chronic radiotelemetric monitoring in Sprague-Dawley rats was used to continuously record electroencephalogram, electromyogram, rest-activity, and body temperature in the same animals before (baseline recording) and after infection. Rats were infected with T.b. brucei. Data were acquired from 1 to 20 d after infection (parasite neuroinvasion initiates at 11-13 d post-infection in this model), and were compared to baseline values. Sleep parameters were manually scored from electroencephalographic-electromyographic tracings. Circadian rhythms of sleep time, slow-wave activity, rest-activity, and body temperature were studied using cosinor rhythmometry. Results revealed alterations of most of the analyzed parameters. In particular, sleep pattern and sleep-wake organization plus rest-activity and body temperature rhythms exhibited early quantitative and qualitative alterations, which became marked around the time interval crucial for parasite neuroinvasion or shortly after. Data derived from actigrams showed close correspondence with those from hypnograms, suggesting that rest-activity could be useful to monitor sleep-wake alterations in African trypanosomiasis.
Ong, Adrian A; Gillespie, M Boyd
To review and assess the current selection of sleep analysis smartphone applications (apps) available for download. The iOS and Google Play mobile app store were searched for sleep analysis apps targeted for consumer use. Alarm clock, sleep-aid, snoring and sleep-talking recorder, fitness tracker apps, and apps geared towards health professionals were excluded. App information and features were obtained from in-store descriptions, and the app developer website. A total of 51 unique sleep apps in both iOS and Google Play stores were included. The apps were rated 3.8/5 in both stores, and had an average price of $1.12 in the iOS store and $0.58 in the Google Play store. >65% of sleep apps report on sleep structure, including duration, time awake, and time in light/deep sleep, while reporting of REM was limited. The availability of extra features was variable, ranging from 4% to 73% of apps. There are a variety of sleep analysis apps with a range of functionality. The apps with the most reviews from the each store are featured. Many apps provide data on sleep structure; however the algorithms are not validated by scientific literature or studies. Since patients may inquire about their sleep habits from these apps, it is necessary for physicians to be aware of the most common apps and the features offered and their limitations in order to properly counsel patients.
Hallows, William C; Ptáček, Louis J; Fu, Ying-Hui
Sleep behavior remains one of the most enigmatic areas of life. The unanswered questions range from "why do we sleep?" to "how we can improve sleep in today's society?" Identification of mutations responsible for altered circadian regulation of human sleep lead to unique opportunities for probing these territories. In this review, we summarize causative circadian mutations found from familial genetic studies to date. We also describe how these mutations mechanistically affect circadian function and lead to altered sleep behaviors, including shifted or shortening of sleep patterns. In addition, we discuss how the investigation of mutations can not only expand our understanding of the molecular mechanisms regulating the circadian clock and sleep duration, but also bridge the pathways between clock/sleep and other human physiological conditions and ailments such as metabolic regulation and migraine headaches.
Mai, Fu-Der; Chen, Li-You; Ling, Yong-Chien; Chen, Bo-Jung; Wu, Un-In; Chang, Hung-Ming
Excessive calcium influx in chemosensitive neurons of area postrema (AP) is detrimental for sympathetic activation and participates in the disruption of cardiovascular activities. Since total sleep deprivation (TSD) is a stressful condition known to harm the cardiovascular function, the present study is aimed to determine whether the in vivo calcium expression in AP would significantly alter following TSD by the use of time-of-flight secondary ion mass spectrometry (TOF-SIMS) and calretinin (a specific calcium sensor protein in AP neurons) immunohistochemistry. The results indicated that in normal rats, the calcium intensity was estimated to be 0.5 × 10 5 at m/ z 40.08. However, following TSD, the intensity for calcium ions was greatly increased to 1.2 × 10 5. Molecular imaging revealed that after TSD, various strongly expressed calcium signals were distributed throughout AP with clear identified profiles instead of randomly scattered within this region in normal rats. Immunohistochemical staining corresponded well with ionic image in which a majority of calcium-enriched gathering co-localized with calretinin positive neurons. The functional significance of TSD-induced calcium augmentation was demonstrated by increased heart rate and mean arterial pressure, clinical markers for cardiovascular dysfunction. Considering AP-mediated sympathetic activation is important for cardiovascular regulation, exaggerated calcium influx in AP would render this neurocircuitry more vulnerable to over-excitation, which might serve as the underlying mechanism for the development of TSD-relevant cardiovascular deficiency.
Truong, Kimberly K; Lam, Michael T; Grandner, Michael A; Sassoon, Catherine S; Malhotra, Atul
Physiological and cellular functions operate in a 24-hour cyclical pattern orchestrated by an endogenous process known as the circadian rhythm. Circadian rhythms represent intrinsic oscillations of biological functions that allow for adaptation to cyclic environmental changes. Key clock genes that affect the persistence and periodicity of circadian rhythms include BMAL1/CLOCK, Period 1, Period 2, and Cryptochrome. Remarkable progress has been made in our understanding of circadian rhythms and their role in common medical conditions. A critical review of the literature supports the association between circadian misalignment and adverse health consequences in sepsis, obstructive lung disease, obstructive sleep apnea, and malignancy. Circadian misalignment plays an important role in these disease processes and can affect disease severity, treatment response, and survivorship. Normal inflammatory response to acute infections, airway resistance, upper airway collapsibility, and mitosis regulation follows a robust circadian pattern. Disruption of normal circadian rhythm at the molecular level affects severity of inflammation in sepsis, contributes to inflammatory responses in obstructive lung diseases, affects apnea length in obstructive sleep apnea, and increases risk for cancer. Chronotherapy is an underused practice of delivering therapy at optimal times to maximize efficacy and minimize toxicity. This approach has been shown to be advantageous in asthma and cancer management. In asthma, appropriate timing of medication administration improves treatment effectiveness. Properly timed chemotherapy may reduce treatment toxicities and maximize efficacy. Future research should focus on circadian rhythm disorders, role of circadian rhythm in other diseases, and modalities to restore and prevent circadian disruption.
Chatzitheochari, S; Arber, SL
Sleep is functional for individual and societal well-being, with partial sleep deprivation associated with adverse health and safety consequences. Surprisingly, sleep is absent from work—life balance debates and has remained largely under-researched by sociologists. This article examines the relationship of insufficient sleep duration with occupational circumstances and family responsibilities, providing a contribution to the examination of the health consequences of working patterns in the U...
Full Text Available The aim of the present study was to characterize the temporal patterns of sleep and wakefulness in a sample of the adult subjects from São Paulo city. All subjects filled the Morningness/Eveningness Questionnaire (MEQ and wore an actigraph for at least three consecutive days. A total of 359 subjects were considered for the analyses. The mean age was 43±14 years, the mean body mass index was 26.7±5.7 kg/m2, and 60% were female. The mean MEQ score was 58.0±10.7. The sleep pattern evaluated by the actigraphic analyses showed that 92% had a monophasic sleep pattern, 7% biphasic, and 1% polyphasic sleep pattern. Cluster analysis, based on time to sleep onset, sleep efficiency, sleep latency, and total sleep time, was able to identify three different groups denominated: morning type, evening type, and undefined type. Morning type subjects were more frequent, older, and had higher MEQ scores than evening type subjects. Our results showed that the actigraph objectively assessed the sleep-wake cycle and was able to discriminate between morning and evening type individuals. These findings suggest that the actigraph could be a valuable tool for assessing temporal sleep patterns, including the circadian preferences.
Insana, Salvatore P.; Montgomery-Downs, Hawley E.
The study aim was to compare sleep, sleepiness, fatigue, and neurobehavioral performance among first-time mothers and fathers during their early postpartum period. Participants were 21 first-time postpartum mother-father dyads (N=42) and seven childless control dyads (N=14). Within their natural environment, participants completed one week of wrist actigraphy monitoring, along with multi-day self-administered sleepiness, fatigue, and neurobehavioral performance measures. The assessment week was followed by an objective laboratory based test of sleepiness. Mothers obtained more sleep compared to fathers, but mothers’ sleep was more disturbed by awakenings. Fathers had greater objectively measured sleepiness than mothers. Mothers and fathers did not differ on subjectively measured sleep quality, sleepiness, or fatigue; however, mothers had worse neurobehavioral performance than fathers. Compared to control dyads, postpartum parents experienced greater sleep disturbance, sleepiness, and sleepiness associated impairments. Study results inform social policy, postpartum sleep interventions, and research on postpartum family systems and mechanisms that propagate sleepiness. PMID:22553114
Littlewood, Donna L; Kyle, Simon D; Carter, Lesley-Anne; Peters, Sarah; Pratt, Daniel; Gooding, Patricia
Sleep problems are a modifiable risk factor for suicidal thoughts and behaviors. Yet, sparse research has examined temporal relationships between sleep disturbance, suicidal ideation, and psychological factors implicated in suicide, such as entrapment. This is the first in-the-moment investigation of relationships between suicidal ideation, objective and subjective sleep parameters, and perceptions of entrapment. Fifty-one participants with current suicidal ideation completed week-long ecological momentary assessments. An actigraph watch was worn for the duration of the study, which monitored total sleep time, sleep efficiency, and sleep latency. Daily sleep diaries captured subjective ratings of the same sleep parameters, with the addition of sleep quality. Suicidal ideation and entrapment were measured at six quasi-random time points each day. Multi-level random intercept models and moderation analyses were conducted to examine the links between sleep, entrapment, and suicidal ideation, adjusting for anxiety and depression severity. Analyses revealed a unidirectional relationship whereby short sleep duration (both objective and subjective measures), and poor sleep quality, predicted the higher severity of next-day suicidal ideation. However, there was no significant association between daytime suicidal ideation and sleep the following night. Sleep quality moderated the relationship between pre-sleep entrapment and awakening levels of suicidal ideation. This is the first study to report night-to-day relationships between sleep disturbance, suicidal ideation, and entrapment. Findings suggest that sleep quality may alter the strength of the relationship between pre-sleep entrapment and awakening suicidal ideation. Clinically, results underscore the importance of assessing and treating sleep disturbance when working with those experiencing suicidal ideation.
This article highlights the potential uses that smartphone applications may have for helping those with sleep problems. Applications in smartphones offer the promised possibility of detection of sleep. From the author's own experience, one can also conclude that sleep applications are approximately as good as polysomnography in detection of sleep time, similar to the conventional wearable actimeters. In the future, sleep applications will help to further enhance awareness of sleep health and to distinguish those who actually poorly and only briefly sleep from those who suffer more likely from paradox insomnia. Copyright © 2016 Elsevier Inc. All rights reserved.
Patel, Pious; Kim, Ji Young; Brooks, Lee J
Chronic sleep problems can lead to difficulties for both the individual and society at large, making it important to effectively measure sleep. This study assessed the accuracy of an iPhone application (app) that could potentially be used as a simple, inexpensive means to measure sleep over an extended period of time in the home. Twenty-five subjects from the ages of 2-14 who were undergoing overnight polysomnography (PSG) were recruited. The phone was placed on the mattress, near their pillow, and recorded data simultaneously with the PSG. The data were then downloaded and certain parameters were compared between the app and PSG, including total sleep time, sleep latency, and time spent in various defined "stages." Although there seemed to be a visual relationship between the graphs generated by the app and PSG, this was not confirmed on numerical analysis. There was no correlation between total sleep time or sleep latency between the app and PSG. Sleep latency from the PSG and latency to "deep sleep" from the app had a significant relationship (p = 0.03). No combination of PSG sleep stages corresponded with app "stages" in a meaningful way. The Sleep Cycle App may have value in increasing the user's awareness of sleep issues, but it is not yet accurate enough to be used as a clinical tool.
Shinomiya, Kazuaki; Shigemoto, Yuki; Omichi, Junji; Utsu, Yoshiaki; Mio, Mitsunobu; Kamei, Chiaki
New sleep disturbance model in rats is useful for estimating the characteristics of some hypnotics. The present study was undertaken to investigate the utility of a sleep disturbance model by placing rats on a grid suspended over water using three kinds of hypnotics, that is, short-acting benzodiazepine (triazolam), intermediate-acting benzodiazepine (flunitrazepam) and long-acting barbiturate (phenobarbital). Electrodes for measurement of EEG and EMG were implanted into the frontal cortex and the dorsal neck muscle of rats. EEG and EMG were recorded with an electroencephalogram. SleepSign ver.2.0 was used for EEG and EMG analysis. Total times of wakefulness, non-REM and REM sleep were measured from 0900 to 1500 hours. In rats placed on the grid suspended over water up to 1 cm under the grid surface, not only triazolam but also flunitrazepam and phenobarbital caused a shortening of sleep latency. Both flunitrazepam and phenobarbital were effective in increasing of total non-REM sleep time in rats placed on sawdust or the grid, and the effects of both drugs in rats placed on the grid were larger than those in rats placed on sawdust. Measurement of the hourly non-REM sleep time was useful for investigating the peak time and duration of effect of the three hypnotics. Phenobarbital showed a decrease in total REM sleep time in rats placed on the grid, although both triazolam and flunitrazepam were without effect. The present insomnia model can be used as a sleep disturbance model for testing not only the sleep-inducing effects but also the sleep-maintaining effects including non-REM sleep and REM sleep of hypnotics.
Eliasson, Arne; Eliasson, Anders; King, Joseph; Gould, Ben; Eliasson, Arn
Poor school performance by adolescent students has been attributed in part to insufficient sleep. It is recognized that a number of factors lead to diminished total sleep time and chief among these are early school start times and sleep phase delay in adolescence. Political initiatives are gaining momentum across the United States to require later school start times with the intent of increasing total sleep time and consequently improving school performance. Later school start times come with significant costs and impact other activities of families and communities. The decision to implement later school start times cannot be made lightly and deserves support of well-performed research on the impact of these changes. A study evaluating the association of academic performance and total sleep time was performed in middle school and high school students in a suburban Maryland school system. Preliminary results of this study show no correlation of total sleep time with academic performance. Before mandating costly changes in school schedules, it would be useful to perform further research to determine the effects of increasing sleep time on the behaviors of adolescent students.
Full Text Available This study investigated the effects of inhalation aromatherapy on sleep disturbance in elderly individuals with dementia. In 19 subjects, normal sleep was observed for a 20-day control period, inhalation aromatherapy was then applied for a 20-day intervention period, and the control and intervention periods were compared. During the intervention period, essential oils were placed nightly on towels around the subjects’ pillows. The measured sleep conditions were sleep latency, total sleep time, sleep efficacy, duration of the longest sustained sleep period, wake time after sleep onset, early morning awakening, total daytime sleep, and the Neuropsychiatric Inventory. Total sleep time was significantly longer in the intervention period than in the control period (p<0.05. The duration of the longest sustained sleep period was significantly longer in the intervention period than in the control period (p<0.05. Early morning awakening in the intervention period was significantly less compared to that in the control period (p<0.05. Total daytime sleep could not be adequately measured and was omitted from the analysis. No significant differences in other sleep conditions were observed. These results indicated positive effects of inhalation aromatherapy on symptoms of sleep disturbance in elderly individuals with dementia.
Full Text Available ABSTRACT CONTEXT AND OBJECTIVE: Impaired autonomic cardiac function is an important consequence of obstructive sleep apnea (OSA. This impairment is mainly due to intermittent hypoxia episodes following apneas. However, the impact of apnea severity on autonomic cardiac function remains unclear. The aim of this study was to evaluate the relationship between the severity of sleep apnea and heart rate turbulence (HRT and heart rate variability (HRV in OSA. DESIGN AND SETTING: Observational cross-sectional study conducted in the Departments of Cardiology and Pulmonary Diseases, Afyon Kocatepe University, Turkey. METHODS: 106 patients with OSA and 27 healthy volunteers were enrolled. Based on apnea hypopnea index (AHI values, obstructive sleep apnea severity was classified as follows: mild OSA (AHI ≥ 5 and 30. HRV and HRT parameters were assessed via 24-hour digital Holter electrocardiogram recordings for all subjects. RESULTS: HRV and HRT results were significantly lower among OSA patients than among control subjects (P < 0.05. However, there were no significant differences in HRT and HRV between the three patient subgroups. Correlations did emerge between AHI and the NN-interval parameter RMSSD and between oxygen desaturation and turbulence slope (respectively: r = -0.22, P = 0.037; and r = -0.28, P = 0.025. CONCLUSION: HRT and HRV results deteriorate in OSA. Correlations between apnea severity and these parameters seem to be present.
Urfer-Maurer, Natalie; Weidmann, Rebekka; Brand, Serge; Holsboer-Trachsler, Edith; Grob, Alexander; Weber, Peter; Lemola, Sakari
Sleep plays an essential role for children's well-being. Because children's sleep is associated with parental sleep patterns, it must be considered in the family context. As a first aim of the present study, we test whether parental insomnia symptoms are related to children's in-home sleep-electroencephalography (EEG). Second, we examine the association between parental insomnia symptoms and maternal and paternal perception of children's sleep using actor-partner interdependence models. A total of 191 healthy children enrolled in public school and aged 7-12 years took part in the study. Ninety-six were formerly very preterm born children. Children underwent in-home sleep-EEG, and parents reported children's sleep-related behavior by using the German version of the Children's Sleep Habits Questionnaire. Further, parents completed the Insomnia Severity Index to report their own insomnia symptoms. Maternal but not paternal insomnia symptoms were related to less children's EEG-derived total sleep time, more stage 2 sleep, less slow wave sleep, later sleep onset time, and later awakening time. Mothers' and fathers' own insomnia symptoms were related to their reports of children's bedtime resistance, sleep duration, sleep anxiety, night wakings, and/or daytime sleepiness. Moreover, maternal insomnia symptoms were associated with paternal reports of children's bedtime resistance, sleep anxiety, and sleep-disordered breathing. The associations between parental insomnia symptoms and parents' perception of children's sleep could not be explained by children's objectively measured sleep. Mothers' insomnia symptoms and children's objective sleep patterns are associated. Moreover, the parents' own insomnia symptoms might bias their perception of children's sleep-related behavior problems. Copyright © 2017 Elsevier B.V. All rights reserved.
Full Text Available Background: For the last few years a topic of overwork on nursing posts has given rise to strong discussions. The author has set herself a goal of answering the question if it is a result of real overwork of this particular profession or rather commonly assumed frustration of this professional group. The aim of this paper is to conduct the analysis of working time on chosen nursing positions in relation to measures of time being used as intervals in the course of conducting standard professional activities during one working day. Material and Methods: Research material consisted of documentation of work time on chosen nursing workplaces, compiled between 2007–2012 within the framework of a nursing course at the Pomeranian Medical University in Szczecin. As a method of measurement a photograph of a working day has been used. Measurements were performed in institutions located in 6 voivodeships in Poland. Results: Results suggest that only 6.5% of total of surveyed representatives of nurse profession spends proper amount of time (meaning: a time set by the applicable standards on work intervals during a working day. Conclusions: The scale of the phenomenon indicates excessive workload for nursing positions, which along with a longer period of time, longer working hours may cause decrease in efficiency of work and cause a drop in quality of provided services. Med Pr 2015;66,(2:165–172
Aishworiya, Ramkumar; Chan, Pofun; Kiing, Jennifer; Chong, Shang Chee; Laino, Armi G; Tay, Stacey Kh
Sleep problems are common in all ages, but may be particularly acute in urban Singapore. This study aims to describe the sleep behaviour of, and to identify any sleep problems in, preschool children. This was a cross-sectional questionnaire survey of 372 children attending local childcare centers. The questionnaire was based on the Children's Sleep Habits Questionnaire (CSHQ), a validated parent-report sleep screening questionnaire that contains 54 items identifying sleep behaviours in children. A total of 372 (40.0%) children participated. The mean age was 4.1 (SD 1.3) years (range, 2 to 6 years). Average total sleep duration was 10.8 hours (SD 1.1) with average night-time sleep duration of 8.5 hours (SD 0.6) and average nap duration of 1.6 hours (SD 1.0). Co-sleeping was common; 80.9% of children shared a room with someone else. The most common sleep problems were in the domains of sleep resistance and morning behaviour; namely: requiring company to fall asleep (n = 272, 73.1%), being afraid to sleep alone (n = 228, 61.6%) and diffi culty in waking up (n = 165, 44.4%). Among parents, 84.1 % (n = 313) perceived that their child's sleep duration was adequate. The duration of sleep in the Singaporean preschool population sampled is signifi cantly lower than recommended values and that of previously described Caucasian populations. Parental perception of sleep adequacy deviates from current recommendations. Given the clear relation of sleep duration with cognitive functioning, learning, and physical growth, this sleep deprivation should be addressed with parental education and opportunistic screening of sleep in well-child follow-ups.
Massa, Jennifer; Stone, Katie L; Wei, Esther K; Harrison, Stephanie L; Barrett-Connor, Elizabeth; Lane, Nancy E; Paudel, Misti; Redline, Susan; Ancoli-Israel, Sonia; Orwoll, Eric; Schernhammer, Eva
Maintaining adequate serum levels of vitamin D may be important for sleep duration and quality; however, these associations are not well understood. We examined whether levels of serum 25(OH)D are associated with objective measures of sleep in older men. Cross-sectional study within a large cohort of community-dwelling older men, the MrOS study. Among 3,048 men age 68 years or older, we measured total serum vitamin D. Objective estimates of nightly total sleep time, sleep efficiency, and wake time after sleep onset (WASO) were obtained using wrist actigraphy worn for an average of 5 consecutive 24-h periods. 16.4% of this study population had low levels of vitamin D (sleep duration, (odds ratio [OR] for the highest (≥ 40.06 ng/mL) versus lowest (sleep efficiency of less than 70% (OR, 1.45; 95% CI, 0.97-2.18; Ptrend = 0.004), after controlling for age, clinic, season, comorbidities, body mass index, and physical and cognitive function. Lower vitamin D levels were also associated with increased WASO in age-adjusted, but not multivariable adjusted models. Among older men, low levels of total serum 25(OH)D are associated with poorer sleep including short sleep duration and lower sleep efficiency. These findings, if confirmed by others, suggest a potential role for vitamin D in maintaining healthy sleep. © 2015 Associated Professional Sleep Societies, LLC.
Montagnese, Sara; Middleton, Benita; Skene, Debra J; Morgan, Marsha Y
Sleep-wake abnormalities are common in patients with cirrhosis but their evaluation is time consuming and laborious. The aim of this study was to assess the validity of a simple Sleep Timing and Sleep Quality Screening questionnaire (STSQS) against an established sleep quality questionnaire and daily sleep diaries. The study population comprised 87 patients with cirrhosis and 19 healthy volunteers. All participants completed the STSQS (sleep quality score range 1-9) and the Pittsburgh Sleep Quality Index (PSQI; total score range: 0-21; scores >5 identify 'poor' sleepers); a subgroup of 35 patients and 12 healthy volunteers also kept daily sleep diaries for 2 weeks. Patients slept significantly less well than the healthy volunteers (total PSQI score: 8.4+/-4.9 vs. 4.6+/-2.5, p4: sensitivity 75%, specificity 93%; patients: STSQS sleep quality >3: sensitivity 83%, specificity 70%). The STSQS provided estimates of habitual sleep timing variables which did not significantly differ from the average data recorded in the sleep diaries, although more variability was observed in the patients. The STSQS provides acceptable estimates of sleep quality and sleep timing and could be used to identify patients with cirrhosis whose sleep behaviour might require further assessment.
Full Text Available Shi Ngar Wong, Mark Halaki, Chin Moi ChowDiscipline of Exercise and Sport Science, University of Sydney, Sydney, NSW, AustraliaAbstract: The sleep–wake cycle is a process not only dictated by homeostatic and circadian factors but also by social and environmental influences. Thus, the total sleep time partly reflects sleep need, which is integral to the dynamics of sleep loss recovery. This study explored the nature of the observed oscillations in total sleep time in healthy adults under spontaneous living conditions. Actigraph-measured sleep data for 13 healthy young male adults were collected over 14 consecutive days and analyzed for habitual sleep duration. The total sleep time periodicity was modeled using the cosinor method for each individual across the 14 days. The findings confirm the existence of periodicity in habitual sleep duration as there were clear periodic patterns in the majority of the participants. Although exclusive to each individual, the observed oscillations may be a resultant response of homeostatic sleep need, circadian timing, and/or social and environmental influences. These findings instigate further indepth studies into the periodicity of sleep duration in healthy individuals to provide a better understanding of sleep need in short versus long sleepers, in predicting work performance, and reducing sleepiness-related accidents following shift work, and how this periodicity may impact sleep treatment outcome in clinical populations.Keywords: sleep regulation, homeostasis, habitual sleep, spontaneous living, healthy males
Klukowski, Mark; Wasilewska, Jolanta; Lebensztejn, Dariusz
Autism spectrum disorder (ASD), a neurodevelopmental disorder with a prevalence of 1 in 68 children, commonly presents with comorbid conditions which include sleep disorders. Sleep disorders reported in ASD include, among others, increased bedtime resistance, insomnia, parasomnia, sleep disordered breathing, morning rise problems, and daytime sleepiness. Polysomnography studies show that children with ASD have altered sleep architecture including shorter total sleep time and longer sleep latency than typically developing peers. Sleep-related problems have been shown to affect overall autism scores, social skills decits, stereotypic behavior, and cognitive performance. Additionally, problematic sleep in children with ASD has been associated with higher levels of parental stress. Underlying causes specically related to sleep disorders are not fully known. Gastrointestinal (GI) disorders are commonly associated with sleep problems in these patients. Children with ASD and GI symptoms have been found to have a higher prevalence of sleep disturbances compared with typically developing peers who do not have GI symptoms. Treatment approaches to children with sleep disorders are varied and range from lifestyle modications and behavioral interventions to drug therapies and surgical interventions. Physicians should take into account GI disorders as possible underlying causes of sleep-related problems in children with ASD. Therapeutic interventions should begin with less invasive methods before progressing to more invasive options such as pharmacotherapy and should be based on medical indications in order to provide effective care while minimizing potential adverse health effects. Evidence-based studies concerning GI and sleep disorders in children with ASD are limited and further studies are warranted.
Herrmann, Evan S; Johnson, Patrick S; Bruner, Natalie R; Vandrey, Ryan; Johnson, Matthew W
Use of amphetamine-type stimulants (e.g., methamphetamine) is associated with acute sleep disruptions. No prior reports have characterized the acute effects of methamphetamine on sleep using polysomnography, the gold standard for objective sleep monitoring. Recreational stimulant users (n=19) completed a baseline assessment, which included questionnaires assessing demographic and substance use characteristics, and the Pittsburgh Sleep Quality Index (PSQI), which assesses sleep quality over the past month. Participants were administered 0mg (placebo), 20mg, or 40mg oral methamphetamine at 08:15h on study days, using a double-blind, randomized, within-subjects design. Sleep was monitored using polysomnography from 22:20 that evening until 06:15 the following morning. PSQI scores indicated more than half of participants reported poor sleep quality at baseline. Methamphetamine dose-dependently increased sleep latency, and decreased total sleep time, sleep efficiency, time in NREM 2 sleep, number of REM periods, and total time in REM sleep. Sleep under placebo conditions was consistent with what would be expected from healthy adults. Morning oral administration of methamphetamine produces robust disruptions in nighttime sleep. Future research should examine relations between stimulant use and sleep disruption in naturalistic settings, with regard to both stimulant abuse and licit prescription use. Copyright © 2017. Published by Elsevier B.V.
Mindell, Jodi A; Leichman, Erin S; Walters, Russel M
Initial studies indicate more independent and consolidated sleep in the first few months in infants who sleep separately. Little is known, however, about the relationship of sleep location (separate room, room-sharing, bed-sharing) with sleep outcomes in older infants (ages 6-12 months). It was expected that those who sleep in a separate room would have better parent-perceived sleep outcomes and more positive sleep health behaviors. Parents of 6236 infants (6-12 months) in the United States (US) and 3798 in an international sample (Australia, Brazil, Canada, Great Britain, and New Zealand) completed a smartphone app-based expanded version of the validated Brief Infant Sleep Questionnaire. A total of 37.2% of the infants in the US and 48.4% in the international sample slept in a separate room. In both samples, infants who slept in a separate room as opposed to room-sharing or bed-sharing had parent-perceived sleep outcomes and sleep-related behaviors that reflected earlier bedtimes, shorter time to fall asleep, more nighttime and total sleep, and increased sleep consolidation. They were also more likely to have a consistent bedtime routine and to fall asleep independently, as well as less likely to feed to sleep at bedtime and during the night. In addition, parents of separate room sleepers perceived bedtime to be less difficult and sleep to be better overall. Overall, 6- to 12-month-old infants who slept in a separate room had better reported sleep outcomes and fewer parent-perceived disturbances at bedtime than infants who room-shared with their parents, as well compared to those who slept in their parents' bed. Copyright © 2017 Elsevier B.V. All rights reserved.
Steven M Thurman
Full Text Available There is extensive laboratory research studying the effects of acute sleep deprivation on biological and cognitive functions, yet much less is known about naturalistic patterns of sleep loss and the potential impact on daily or weekly functioning of an individual. Longitudinal studies are needed to advance our understanding of relationships between naturalistic sleep and fluctuations in human health and performance, but it is first necessary to understand the efficacy of current tools for long-term sleep monitoring. The present study used wrist actigraphy and sleep log diaries to obtain daily measurements of sleep from 30 healthy adults for up to 16 consecutive weeks. We used non-parametric Bland-Altman analysis and correlation coefficients to calculate agreement between subjectively and objectively measured variables including sleep onset time, sleep offset time, sleep onset latency, number of awakenings, the amount of wake time after sleep onset, and total sleep time. We also examined compliance data on the submission of daily sleep logs according to the experimental protocol. Overall, we found strong agreement for sleep onset and sleep offset times, but relatively poor agreement for variables related to wakefulness including sleep onset latency, awakenings, and wake after sleep onset. Compliance tended to decrease significantly over time according to a linear function, but there were substantial individual differences in overall compliance rates. There were also individual differences in agreement that could be explained, in part, by differences in compliance. Individuals who were consistently more compliant over time also tended to show the best agreement and lower scores on behavioral avoidance scale (BIS. Our results provide evidence for convergent validity in measuring sleep onset and sleep offset with wrist actigraphy and sleep logs, and we conclude by proposing an analysis method to mitigate the impact of non-compliance and measurement
Vienne, Julie; Spann, Ryanne; Guo, Fang; Rosbash, Michael
Study Objectives: Physiological studies show that aging affects both sleep quality and quantity in humans, and sleep complaints increase with age. Along with knowledge about the negative effects of poor sleep on health, understanding the enigmatic relationship between sleep and aging is important. Because human sleep is similar to Drosophila (fruit fly) sleep in many ways, we addressed the effects of aging on sleep in this model organism. Methods: Baseline sleep was recorded in five different Drosophila genotypes raised at either 21°C or 25°C. The amount of sleep recovered was then investigated after a nighttime of sleep deprivation (12 h) and after chronic sleep deprivation (3 h every night for multiple nights). Finally, the effects of aging on arousal, namely, sensitivity to neuronal and mechanical stimuli, were studied. Results: We show that fly sleep is affected by age in a manner similar to that of humans and other mammals. Not only do older flies of several genotypes have more fragmented sleep and reduced total sleep time compared to young flies, but older flies also fail to recover as much sleep after sleep deprivation. This suggests either lower sleep homeostasis and/or a failure to properly recover sleep. Older flies also show a decreased arousal threshold, i.e., an increased response to neuronal and mechanical wake-promoting stimuli. The reduced threshold may either reflect or cause the reduced recovery sleep of older flies compared to young flies after sleep deprivation. Conclusions: Further studies are certainly needed, but we suggest that the lower homeostatic sleep drive of older flies causes their decreased arousal threshold. Citation: Vienne J, Spann R, Guo F, Rosbash M. Age-related reduction of recovery sleep and arousal threshold in Drosophila. SLEEP 2016;39(8):1613–1624. PMID:27306274
Wang, Xiang-Yun; Qian, Yan-Fei; Gong, Sheng-Cheng; Tan, Mo; Tan, Xin; Yang, Yan; Li, Ling-Di; Huang, Chao-Quan
To study the adverse effects of sleep problems and sleep insufficiency on attention in class and pupils' acadamic achievements. A total of 1138 students from four primary schools at ages of 6-12 years were randomly sampled from four districts of Changsha city, Hunan Province June 2009 to April 2010. The inquired items included sleep problems, sleep time, sleep quality, attention in class and academic achievements. Teachers and parents observed the pupils according to the unified requirements for 3 months and then filled out the questionnaires. The total valid inquiry tables were 1091 with the answering rate of 95.87%, including 549 boys and 542 girls. The sleep quality was more poor in children with sleep problems or sleep insufficiency than in children with normal sleep. The sleep quality was reduced and aggravated along with the increasing sleep problems and the reducing sleep time. The attention in class and academic achievements in children with sleep problems or sleep insufficiency were more poor than in children with normal sleep. The sleep quality index was negatively correlated with attention in class and academic achievements. The attention in class was positively correlated with academic achievements. The decline in sleep quality directly affects the attention in class and reduce the academic achievements in primary school children.
Werner, Kimberly B; Griffin, Michael G; Galovski, Tara E
Sleep disturbance may be the most often endorsed symptom of posttraumatic stress disorder (PTSD). Much of this research is based on subjective reports from trauma survivors; however, objective measures of sleep-related impairment have yielded findings inconsistent with self-report data. More studies investigating subjective and objective assessments concordantly are needed to understand sleep impairment in PTSD. The current study examined PTSD-related sleep disturbance in a female interpersonal violence cohort with full PTSD diagnoses (N=51) assessing subjective (global and daily diary measures) and objective (actigraphy) sleep measures concurrently. PTSD severity was positively associated with global, subjective reports of sleep impairment and insomnia. Subjective measures of sleep (including global sleep impairment, insomnia, and daily sleep diary reports of total sleep time, sleep efficiency, and sleep onset latency) were moderately to strongly correlated. However, no significant correlations between subjective and objective reports of sleep impairment were found in this cohort. Analyses demonstrated an overall elevation in subjectively reported sleep impairment when compared to objective measurement assessed concurrently. Findings demonstrate a lack of agreement between subjective and objective measurements of sleep in a PTSD-positive female cohort, suggesting objective and subjective sleep impairments are distinct sleep parameters that do not necessarily directly co-vary. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Kwon, Jeoung A.; Lee, Minjee; Yoo, Ki-Bong; Park, Eun-Cheol
Allergic rhinitis (AR) is the most common chronic disorder in the pediatric population. Although several studies have investigated the correlation between AR and sleep-related issues, the association between the duration and time of sleep and AR has not been analyzed in long-term national data. This study investigated the relationship between sleep time and duration and AR risk in middle- and high-school students (adolescents aged 12-18). We analyzed national data from the Korea Youth Risk Be...
Sekine, M; Tatsuse, T; Cable, N; Chandola, T; Marmot, M
This study aimed to evaluate (i) whether work, family, behavioral and sleep quality characteristics differ among individuals with different time in bed (TIB), and (ii) whether and how much the U-shaped associations between TIB and health can be explained by these characteristics. Participants were 3510 employees (2371 males and 1139 females) aged 20-65 years working in local government in Japan. They completed a questionnaire regarding work, family, and behavioral characteristics. Sleep quality and physical and mental functioning were evaluated using the Pittsburgh Sleep Quality Index and the Short Form 36. High job demands, long work hours, and high work-family conflict were more prevalent among those with short TIB. Those with long TIB had daily drinking habits. Whereas those with short TIB had poor sleep, mainly due to poor subjective sleep quality and daytime dysfunction, those with long TIB had poor sleep, mainly due to long sleep latency, poor sleep efficiency and sleep disturbances. The U-shaped associations between TIB and poor physical and mental health, with the best health observed in those spending ~8 h in bed, weakened considerably after adjustment for sleep quality, followed by work and family characteristics. After adjusting for behavioral characteristics and long-standing illnesses, the associations hardly changed. The U-shaped associations between TIB and health may be explained by U-shaped associations between TIB and poor sleep and psychosocial stress in work and family life. Copyright © 2014 Elsevier B.V. All rights reserved.
Boesen, H C; Andersen, J H; Bendtsen, A O
. Delirium assessment was done using the confusion assessment method for the intensive care unit (CAM-ICU). RESULTS: Of four patients who were delirium free, only one had identifiable sleep on PSG. Sleep was disrupted with loss of circadian rhythm, and diminished REM sleep. In the remaining three patients...... the PSGs were atypical, meaning that no sleep signs were found, and sleep could not be quantified from the PSGs. Clinical total sleep time (ClinTST) ranged from 2.0-13.1 h in patients without delirium. Six patients with delirium all had atypical PSGs, so sleep could not be quantified. Short periods of REM......BACKGROUND: Sleep deprivation and delirium are major problems in the ICU. We aimed to assess the sleep quality by polysomnography (PSG) in relation to delirium in mechanically ventilated non-sedated ICU patients. METHODS: Interpretation of 24-h PSG and clinical sleep assessment in 14 patients...
Baron, Kelly Glazer; Reid, Kathryn J; Zee, Phyllis C
Exercise improves sleep quality, mood, and quality of life among older adults with insomnia. The purpose of the study was to evaluate the daily bidirectional relationships between exercise and sleep in a sample of women with insomnia. Participants included 11 women (age M = 61.27, SD 4.15) with insomnia who engaged in 30 min of aerobic exercise 3 times per week. Self-reported sleep quality was assessed at baseline and at 16 weeks. Sleep and exercise logs and wrist activity were collected continuously. Sleep variables included subjective sleep quality and objective measures recorded via wrist actigraphy (sleep onset latency [SOL], total sleep time [TST], sleep efficiency [SE], wake after sleep onset [WASO], and fragmentation index [FI]). Age, subjective sleep quality, TST, SOL, and physical fitness at baseline were tested as moderators of the daily effects. TST, SE, and self-reported global sleep quality improved from baseline to 16 weeks (p values exercise session duration (p exercise was not associated with subjective or objective sleep variables during the corresponding night. However, participants had shorter exercise duration following nights with longer SOL (p exercise duration (p exercise was stronger in participants who had shorter TST at baseline. Results suggest that sleep influences next day exercise rather than exercise influencing sleep. The relationship between TST and next day exercise was stronger for those with shorter TST at baseline. These results suggest that improving sleep may encourage exercise participation.
Gander, P. H.; Myhre, G.; Graeber, R. C.; Andersen, H. T.; Lauber, J. K.
Physiological and psychological disruptions caused by transmeridian flights may affect the ability of flight crews to meet operational demands. To study these effects, 9 Royal Norwegian Airforces P3-Orion crewmembers flew from Norway to California (-9 hr), and back (+9 hr). Rectal temperature, heart rate and wrist activity were recorded every 2 min, fatigue and mood were rated every 2 hr during the waking day, and logs were kept of sleep times and ratings. Subjects also completed 4 personality inventories. The time-zone shifts produced negative changes in mood which persisted longer after westward flights. Sleep quality (subjective and objective) and duration were slightly disrupted (more after eastward flights). The circadian rhythms of sleep/wake and temperature both completed the 9-hr delay by day 5 in California, although temperature adjusted more slowly. The size of the delay shift was significantly correlated with scores on extraversion and achievement need personality scales. Response to the 9-hr advance were more variable. One subject exhibited a 15-hr delay in his temperature rhythm, and an atypical sleep/nap pattern. On average, the sleep/wake cycle (but not the temperature rhythm), completed the 9-hr advance by the end of the study. Both rhythms adapted more slowly after the eastward flight.
Matthew William Driller
Full Text Available OBJECTIVE: Differences in sleep results due to the placement of actigraphy devices (non-dominant vs. dominant wrist are yet to be determined. METHODS: 65 nights of data from 13 adult participants was collected while participants wore two actigraphy devices, one on each wrist. Sleep indices including total sleep time (TST, total time in bed (TTB, sleep efficiency (SE%, sleep latency (SL, wake after sleep onset (WASO, sleep onset time (SOT and wake time (WT were assessed between the two devices. RESULTS: There were no significant differences between devices for any of the measured sleep variables (p>0.05. SE%, SL and WASO resulted in high correlations between devices (0.89, 0.89 and 0.76, respectively, with all other sleep variables resulting in very high correlations (>0.90 between devices. CONCLUSIONS: Based on our results, it does not seem critical which wrist the actigraphy device is worn on for measuring key sleep variables.
Yetton, Benjamin D; McDevitt, Elizabeth A; Cellini, Nicola; Shelton, Christian; Mednick, Sara C
The pattern of sleep stages across a night (sleep architecture) is influenced by biological, behavioral, and clinical variables. However, traditional measures of sleep architecture such as stage proportions, fail to capture sleep dynamics. Here we quantify the impact of individual differences on the dynamics of sleep architecture and determine which factors or set of factors best predict the next sleep stage from current stage information. We investigated the influence of age, sex, body mass index, time of day, and sleep time on static (e.g. minutes in stage, sleep efficiency) and dynamic measures of sleep architecture (e.g. transition probabilities and stage duration distributions) using a large dataset of 3202 nights from a non-clinical population. Multi-level regressions show that sex effects duration of all Non-Rapid Eye Movement (NREM) stages, and age has a curvilinear relationship for Wake After Sleep Onset (WASO) and slow wave sleep (SWS) minutes. Bayesian network modeling reveals sleep architecture depends on time of day, total sleep time, age and sex, but not BMI. Older adults, and particularly males, have shorter bouts (more fragmentation) of Stage 2, SWS, and they transition less frequently to these stages. Additionally, we showed that the next sleep stage and its duration can be optimally predicted by the prior 2 stages and age. Our results demonstrate the potential benefit of big data and Bayesian network approaches in quantifying static and dynamic architecture of normal sleep.
Amanda E. Staiano
Full Text Available This cross-sectional study examined differences in children’s health behaviors during school term (ST versus school holiday (SH: June–July and how associations changed when weather characteristics were considered. Children aged 5–18 years (n = 406 from a subtropical climate reported behaviors over 20 months. Multivariable regression models controlling for age, sex, race and body mass index z-score（BMIz ） were used to examine associations between SH and each behavior. A second model included heat index, precipitation and daylight hours. Strenuous activity, moderate activity, total activity and TV viewing were significantly higher during SH than ST. After adjusting for weather characteristics, total activity remained significantly higher during SH, but the association with TV viewing was attenuated. Youth surveyed during high precipitation were significantly less likely to meet physical activity guidelines. There were no significant associations between SH and meeting sleep, physical activity or screen-time guidelines. Weather characteristics influenced associations between SH and youth’s physical activity and TV viewing.
Lampert, Thomas; Plano, Andrea; Austin, Jim; Platt, Bettina
The automatic identification of sleep stages in electroencephalography (EEG) time-series is a long desired goal for researchers concerned with the study of sleep disorders. This paper presents advances towards achieving this goal, with particular application to EEG time-series recorded from mice. Approaches in the literature apply supervised learning classifiers, however, these do not reach the performance levels required for use within a laboratory. In this paper, detection reliability is increased, most notably in the case of REM stage identification, by naturally decomposing the problem and applying a support vector machine (SVM) based classifier to each of the EEG channels. Their outputs are integrated within a multiple classifier system. Furthermore, there exists no general consensus on the ideal choice of parameter values in such systems. Therefore, an investigation into the effects upon the classification performance is presented by varying parameters such as the epoch length; features size; number of training samples; and the method for calculating the power spectral density estimate. Finally, the results of these investigations are brought together to demonstrate the performance of the proposed classification algorithm in two cases: intra-animal classification and inter-animal classification. It is shown that, within a dataset of 10 EEG recordings, and using less than 1% of an EEG as training data, a mean classification errors of Awake 6.45%, NREM 5.82%, and REM 6.65% (with standard deviations less than 0.6%) are achieved in intra-animal analysis and, when using the equivalent of 7% of one EEG as training data, Awake 10.19%, NREM 7.75%, and REM 17.43% are achieved in inter-animal analysis (with mean standard deviations of 6.42%, 2.89%, and 9.69% respectively). A software package implementing the proposed approach will be made available through Cybula Ltd. Copyright © 2015 Elsevier B.V. All rights reserved.
Hermida, Ramón C; Ayala, Diana E; Mojón, Artemio; Fernández, José R
We investigated the prognostic value of clinic and ambulatory BP (ABP) to predict new-onset diabetes and whether risk reduction is related to the progressive decrease of clinic BP or awake or asleep ABP. We prospectively evaluated 2,656 individuals without diabetes, 1,292 men and 1,364 women, 50.6 ± 14.3 years of age, with baseline BP ranging from normotension to hypertension according to ABP criteria. At baseline and annually (more frequently if hypertension treatment was adjusted based on ABP) thereafter, ABP and physical activity (wrist actigraphy) were simultaneously monitored for 48 h to accurately derive the awake and asleep BP means. During a 5.9-year median follow-up, 190 participants developed type 2 diabetes. The asleep systolic ABP mean was the most significant predictor of new-onset diabetes in a Cox proportional-hazard model adjusted for age, waist circumference, glucose, chronic kidney disease (CKD) and hypertension treatment. Daytime clinic BP and awake or 48 h ABP mean had no predictive value when corrected by the asleep ABP mean. Analyses of BP changes during follow-up revealed a 30% reduction in the risk of new-onset diabetes per 1-SD decrease in asleep systolic ABP mean, independent of changes in clinic BP or awake or 48 h ABP means. Sleep-time BP is a highly significant independent prognostic marker for new-onset diabetes. Alteration in sleep-time BP regulation seems to precede, rather than follow, the development of new-onset diabetes. Most important, lowering asleep BP, a novel therapeutic target requiring ABP evaluation, could be a significant method for reducing new-onset diabetes risk.
Buman, Matthew P; Kline, Christopher E; Youngstedt, Shawn D; Phillips, Barbara; Tulio de Mello, Marco; Hirshkowitz, Max
Excess sitting is emerging as a novel risk factor for cardiovascular disease, diabetes, mental illness, and all-cause mortality. Physical activity, distinct from sitting, is associated with better sleep and lower risk for OSA, yet relationships among sitting behaviors and sleep/OSA remain unknown. We examined whether total sitting time and sitting while viewing television were associated with sleep duration and quality, OSA risk, and sleepiness. The 2013 National Sleep Foundation Sleep in America Poll was a cross-sectional study of 1,000 adults aged 23 to 60 years. Total sitting time, time watching television while sitting, sleep duration and quality, OSA risk, and daytime sleepiness were assessed. After adjusting for confounding factors (including BMI and physical activity), each additional hour per day of total sitting was associated with greater odds of poor sleep quality (OR [95% CI] = 1.06 [1.01, 1.11]) but not with other sleep metrics (including sleep duration), OSA risk, or daytime sleepiness. For television viewing while sitting, each additional hour per day was associated with greater odds of long sleep onset latency (≥ 30 min) (OR = 1.15 [1.04, 1.27]), waking up too early in the morning (OR = 1.12 [1.03, 1.23]), poor sleep quality (OR = 1.12 [1.02, 1.24]), and "high risk" for OSA (OR = 1.15 [1.04, 1.28]). Based upon an interaction analysis, regular physical activity was protective against OSA risk associated with television viewing (P = .04). Excess sitting was associated with relatively poor sleep quality. Sitting while watching television was associated with relatively poor sleep quality and OSA risk and may be an important risk factor for sleep disturbance and apnea risk.
Huang, Sha; Deshpande, Aadya; Yeo, Sing-Chen; Lo, June C.; Chee, Michael W.L.; Gooley, Joshua J.
Study Objectives: The ability to recall facts is improved when learning takes place at spaced intervals, or when sleep follows shortly after learning. However, many students cram for exams and trade sleep for other activities. The aim of this study was to examine the interaction of study spacing and time in bed (TIB) for sleep on vocabulary learning in adolescents. Methods: In the Need for Sleep Study, which used a parallel-group design, 56 adolescents aged 15–19 years were randomly assigned to a week of either 5 h or 9 h of TIB for sleep each night as part of a 14-day protocol conducted at a boarding school. During the sleep manipulation period, participants studied 40 Graduate Record Examination (GRE)-type English words using digital flashcards. Word pairs were presented over 4 consecutive days (spaced items), or all at once during single study sessions (massed items), with total study time kept constant across conditions. Recall performance was examined 0 h, 24 h, and 120 h after all items were studied. Results: For all retention intervals examined, recall of massed items was impaired by a greater amount in adolescents exposed to sleep restriction. In contrast, cued recall performance on spaced items was similar between sleep groups. Conclusions: Spaced learning conferred strong protection against the effects of sleep restriction on recall performance, whereas students who had insufficient sleep were more likely to forget items studied over short time intervals. These findings in adolescents demonstrate the importance of combining good study habits and good sleep habits to optimize learning outcomes. Citation: Huang S, Deshpande A, Yeo SC, Lo JC, Chee MW, Gooley JJ. Sleep restriction impairs vocabulary learning when adolescents cram for exams: the Need for Sleep Study. SLEEP 2016;39(9):1681–1690. PMID:27253768
The aim of this study was to investigate the effects of long work hours and poor sleep characteristics on workplace injury. A total of 1891 male employees, aged 18-79 years (mean 45 years), in 296 small- and medium-scale businesses in a suburb of Tokyo were surveyed by means of a self-administered questionnaire during August-December 2002. Work hours and sleep characteristics, including daily sleep hours, subjective sleep sufficiency, sleep quality and easiness to wake up in the morning, were evaluated. Information on workplace injury in the past 1-year period was self-reported. The risk of workplace injury associated with work hours and poor sleep was estimated using multivariate logistic regression with odds ratio (ORs) and 95% confidence intervals as measures of associations. Compared with those working 6-8 h day(-1) with good sleep characteristics, positive interactive effects for workplace injury were found between long work hours (>8-10 h day(-1) or >10 h day(-1) ) and short sleep duration (Long work hours (aOR, 1.31-1.48), subjective insufficient sleep (aOR, 1.49) and sleeping poorly at night (aOR, 1.72) were also independently associated with workplace injury. This study suggests that long work hours coupled with poor sleep characteristics are synergistically associated with increased risk of workplace injury. Greater attention should be paid to manage/treat poor sleep and reduce excessive work hours to improve safety at the workplace. 2011 European Sleep Research Society.
Meerlo, P.; Koehl, M.; van der Borght, K.; Turek, F. W.
Chronic sleep restriction is an increasing problem in many countries and may have many, as yet unknown, consequences for health and well being. Studies in both humans and rats suggest that sleep deprivation may activate the hypothalamic-pituitary-adrenal (HPA) axis, one of the main neuroendocrine stress systems. However, few attempts have been made to examine how sleep loss affects the HPA axis response to subsequent stressors. Furthermore, most studies applied short-lasting total sleep deprivation and not restriction of sleep over a longer period of time, as often occurs in human society. Using the rat as our model species, we investigated: (i) the HPA axis activity during and after sleep deprivation and (ii) the effect of sleep loss on the subsequent HPA response to a novel stressor. In one experiment, rats were subjected to 48 h of sleep deprivation by placing them in slowly rotating wheels. Control rats were placed in nonrotating wheels. In a second experiment, rats were subjected to an 8-day sleep restriction protocol allowing 4 h of sleep each day. To test the effects of sleep loss on subsequent stress reactivity, rats were subjected to a 30-min restraint stress. Blood samples were taken at several time points and analysed for adrenocorticotropic hormone (ACTH) and corticosterone. The results show that ACTH and corticosterone concentrations were elevated during sleep deprivation but returned to baseline within 4 h of recovery. After 1 day of sleep restriction, the ACTH and corticosterone response to restraint stress did not differ between control and sleep deprived rats. However, after 48 h of total sleep deprivation and after 8 days of restricted sleep, the ACTH response to restraint was significantly reduced whereas the corticosterone response was unaffected. These results show that sleep loss not only is a mild activator of the HPA axis itself, but also affects the subsequent response to stress. Alterations in HPA axis regulation may gradually appear under
Chatburn, Alex; Kohler, Mark J; Payne, Jessica D; Drummond, Sean P A
False memory has been claimed to be the result of an associative process of generalisation, as well as to be representative of memory errors. These can occur at any stage of memory encoding, consolidation, or retrieval, albeit through varied mechanisms. The aim of this paper is to experimentally determine: (i) if cognitive dysfunction brought about by sleep loss at the time of stimulus encoding can influence false memory production; and (ii) whether this relationship holds across sensory modalities. Subjects undertook both the Deese-Roedigger-McDermott (DRM) false memory task and a visual task designed to produce false memories. Performance was measured while subjects were well-rested (9h Time in Bed or TIB), and then again when subjects were either sleep restricted (4h TIB for 4 nights) or sleep deprived (30h total SD). Results indicate (1) that partial and total sleep loss produced equivalent effects in terms of false and veridical verbal memory, (2) that subjects performed worse after sleep loss (regardless of whether this was partial or total sleep loss) on cued recognition-based false and veridical verbal memory tasks, and that sleep loss interfered with subjects' ability to recall veridical, but not false memories under free recall conditions, and (3) that there were no effects of sleep loss on a visual false memory task. This is argued to represent the dysfunction and slow repair of an online verbal associative process in the brain following inadequate sleep. Copyright © 2016 Elsevier Inc. All rights reserved.
Watson, Nathaniel F; Martin, Jennifer L; Wise, Merrill S; Carden, Kelly A; Kirsch, Douglas B; Kristo, David A; Malhotra, Raman K; Olson, Eric J; Ramar, Kannan; Rosen, Ilene M; Rowley, James A; Weaver, Terri E; Chervin, Ronald D
During adolescence, internal circadian rhythms and biological sleep drive change to result in later sleep and wake times. As a result of these changes, early middle school and high school start times curtail sleep, hamper a student's preparedness to learn, negatively impact physical and mental health, and impair driving safety. Furthermore, a growing body of evidence shows that delaying school start times positively impacts student achievement, health, and safety. Public awareness of the hazards of early school start times and the benefits of later start times are largely unappreciated. As a result, the American Academy of Sleep Medicine is calling on communities, school boards, and educational institutions to implement start times of 8:30 AM or later for middle schools and high schools to ensure that every student arrives at school healthy, awake, alert, and ready to learn. © 2017 American Academy of Sleep Medicine
Staunton, Craig; Gordon, Brett; Custovic, Edhem; Stanger, Jonathan; Kingsley, Michael
To assess sleep patterns and associations between sleep and match performance in elite Australian female basketball players. Prospective cohort study. Seventeen elite female basketball players were monitored across two consecutive in-season competitions (30 weeks). Total sleep time and sleep efficiency were determined using triaxial accelerometers for Baseline, Pre-match, Match-day and Post-match timings. Match performance was determined using the basketball efficiency statistic (EFF). The effects of match schedule (Regular versus Double-Header; Home versus Away) and sleep on EFF were assessed. The Double-Header condition changed the pattern of sleep when compared with the Regular condition (F (3,48) =3.763, P=0.017), where total sleep time Post-match was 11% less for Double-Header (mean±SD; 7.2±1.4h) compared with Regular (8.0±1.3h; P=0.007). Total sleep time for Double-Header was greater Pre-match (8.2±1.7h) compared with Baseline (7.1±1.6h; P=0.022) and Match-day (7.3±1.5h; P=0.007). Small correlations existed between sleep metrics at Pre-match and EFF for pooled data (r=-0.39 to -0.22; P≥0.238). Relationships between total sleep time and EFF ranged from moderate negative to large positive correlations for individual players (r=-0.37 to 0.62) and reached significance for one player (r=0.60; P=0.025). Match schedule can affect the sleep patterns of elite female basketball players. A large degree of inter-individual variability existed in the relationship between sleep and match performance; nevertheless, sleep monitoring might assist in the optimisation of performance for some athletes. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Laberge, Luc; Ledoux, Élise; Auclair, Julie; Gaudreault, Marco
Adolescents who work while attending school are reported to sleep less than those who do not. This study aimed to identify factors associated with short sleep duration in students who work during the school year. A cross-sectional survey aiming to describe working conditions and occupational safety and health was completed by representative…
... plus indirect costs due to missed days of work, decreased productivity, and other factors. People who have trouble sleeping ... with insomnia or sleep problems caused by shift work or jet lag. Research on the use of ... stress reduction (a type of meditation), yoga, massage therapy, ...
Full Text Available Aims. It is known that sleep has a major role in the regulation of endocrine functions and glucose metabolism. However, it is not clear whether the sleep pattern is affected at or prior to the onset of diabetes, among those with prediabetes. The purpose of this study was to determine the association of sleep patterns and prediabetes in Qazvin, Iran. Methods. A representative sample of residents of Qazvin was selected by multistage cluster random sampling method in 2011. Plasma glucose level and sleep quality were measured cross-sectionally as well as demographic characteristics. A logistic regression analysis was used to examine the association of sleep status and prediabetes. Results. Mean age was 39.3 ± 10.1 years. Of 958, 474 (49.47% were female. Poor sleep quality was associated with 2.197-fold increased risk of prediabetes after adjustment for age, gender, body mass index, and metabolic syndrome. Conclusion. This study provides evidences that subjects with poor sleep quality are more likely to develop prediabetes than people with good sleep quality.
Samuel Alan Stewart
Full Text Available Obstructive sleep apnea is a common condition within the Canadian population. The current gold standard for diagnosis and management of patients is in-laboratory (in-lab polysomnography; however, the limited availability of testing options for patients has led to long wait times and increased disease burden within the population. The Sleep Research Laboratory in Saskatoon (Saskatchewan implemented a home management program to run in parallel with the in-lab system several years ago in an effort to increase their capacity and reduce wait times. The present study was a retrospective analysis of all patients referred to the program between 2009 and 2012. The home management system has improved wait times by diagnosing and managing up to one-half of the referred patient population, reducing the wait for in-lab treatment from a median of 152 days in 2009 to 92 days in 2012 (P<0.0001. Moving forward, home management can provide a viable alternative to in-lab testing for patients who meet strict entry criteria, reducing the in-lab workload and, ultimately, reducing wait times.
Full Text Available Background: Mounting evidence demonstrates that individuals with stroke benefit from sleep to enhance learning of a motor task. While stage NREM2 sleep and REM sleep have been associated with off-line motor skill learning in neurologically-intact individuals, it remains unknown which sleep parameters or specific sleep stages are associated with off-line motor skill learning in individuals with stroke. Methods: Twenty individuals with chronic stroke (> 6 months following stroke and 10 neurologically slept for three consecutive nights in a sleep laboratory with polysomnography. Participants practiced a tracking task the morning before the third night and underwent a retention test the morning following the third night. Off-line learning on the tracking task was assessed. Pearson’s correlations assessed for associations between the magnitude of off-line learning and sleep variables, age, upper extremity motor function, stroke severity, depression and time since stroke occurrence.Results: Individuals with stroke performed with significantly less error on the tracking task following a night of sleep (p=.006 while the control participants did not (p=.816. Increased sleep efficiency (r= -.285, less time spent in stage NREM3 sleep (r=.260, and more time spent in stage REM sleep (r= -.266 was weakly-to-moderately associated with increased magnitude of off-line motor learning. Furthermore, higher upper-extremity motor function (r = -.400, lower stroke severity (r = .360, and less time since stroke occurrence (r=.311 were moderately associated with increased magnitude of off-line motor learning. Conclusion: This study is the first study to provide insight into which sleep stages and individual characteristics may be associated with off-line learning in people with stroke. Future work should continue to understand which factors or combination of factors promote off-line motor learning in people with neurologic injury to best promote motor recovery in
Corser, N C
Physiologic and psychologic changes associated with sleep disturbance decrease the ability of a critically ill child to adapt to hospitalization and thus hamper recovery. Research demonstrates that intensive care settings interfere with sleep of adults, but little is known about the impact of these settings on children's sleep. An exploratory field study was conducted to describe the sleep-wake patterns of 1- and 2-year-old children in intensive care, identify intensive care environmental stimuli associated with sleep and waking states, compare the intensive care sleep-wake pattern to the pre-illness sleep-wake pattern, and determine the time required for children to return to their pre-illness sleep-wake pattern. Twelve children aged 13 to 35 months composed the sample for the study. Pre-illness and postdischarge sleep patterns, sleep patterns during a 12-hour night in the pediatric intensive care unit (PICU), and external and internal environmental stimuli were measured. Prior to hospitalization, subjects demonstrated sleep similar to that documented in healthy children. Children in the PICU experienced a significant loss of sleep, frequent awakenings, and a virtual rapid eye movement (REM) sleep deprivation. External environmental stimuli of light, noise, and caregiver activity were negatively correlated with sleep state. Pain and treatment with benzodiazepines were associated with sleep acquisition. Sleep changes persisted after discharge from the PICU and the hospital. Total sleep time recovered more rapidly than nighttime awakening. Parents perceived that their child's sleep remained different longer than total sleep time and night awakening values demonstrated.
Malone, Susan Kohl
Cognition, memory, safety, mental health, and weight are all affected by inadequate sleep. Biological studies indicate significant changes in sleep architecture during adolescence, such as changes in melatonin secretion, and a need for greater total sleep time. Yet, social contexts and cultural values impinge on these changing biological sleep…
Wirz-Justice, A; Van den Hoofdakker, RH
Manipulations of the sleep-wake cycle, whether of duration (total or partial sleep deprivation [SD]) or timing (partial SD, phase advance), have profound and rapid effects on depressed mood in 60% of all diagnostic subgroups of affective disorders. Relapse after recovery sleep is less when patients
Harvey, Allison G.; Tang, Nicole K. Y.
Insomnia is prevalent, causing severe distress and impairment. This review focuses on illuminating the puzzling finding that many insomnia patients misperceive their sleep. They overestimate their sleep onset latency (SOL) and underestimate their total sleep time (TST), relative to objective measures. This tendency is ubiquitous (although not…
Astill, Rebecca G; Verhoeven, Dorit; Vijzelaar, Romy L; Van Someren, Eus J W
To investigate the effects of real-life stress on the sleep of adolescents, we performed a repeated-measures study on actigraphic sleep estimates and subjective measures during one regular school week, two stressful examination weeks and a week's holiday. Twenty-four adolescents aged 17.63 ± 0.10 years (mean ± standard error of the mean) wore actigraphs and completed diaries on subjective stress, fatigue, sleep quality, number of examinations and consumption of caffeine and alcohol for 4 weeks during their final year of secondary school. The resulting almost 500 assessments were analysed using mixed-effect models to estimate the effects of mere school attendance and additional examination stress on sleep estimates and subjective ratings. Total sleep time decreased from 7:38 h ± 12 min during holidays to 6:40 h ± 12 min during a regular school week. This 13% decrease elicited a partial compensation, as indicated by a 3% increase in sleep efficiency and a 6% decrease in the duration of nocturnal awakenings. During examination weeks total sleep time decreased to 6:23 h ± 8 min, but it was now accompanied by a decrease in sleep efficiency and subjective sleep quality and an increase in wake bout duration. In conclusion, school examination stress affects the sleep of adolescents. The compensatory mechanism of more consolidated sleep, as elicited by the sleep restriction associated with mere school attendance, collapsed during 2 weeks of sustained examination stress. © 2013 European Sleep Research Society.
Full Text Available Xi-Jian Dai,1,2* Chun-Lei Liu,3,4* Ren-Lai Zhou,3 Hong-Han Gong,1 Bin Wu,5 Lei Gao,1 Yi-Xiang J Wang2 1Department of Radiology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China; 2Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, People’s Republic of China; 3Beijing Key Lab of Applied Experimental Psychology, School of Psychology, and National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, People’s Republic of China; 4School of Education, Qufu Normal University, Qufu, Shandong, People’s Republic of China; 5National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, Beijing, People’s Republic of China *These authors have contributed equally to this work Objective: The aim of this study is to use resting-state functional connectivity (rsFC and amplitude of low-frequency fluctuation (ALFF methods to explore intrinsic default-mode network (DMN impairment after sleep deprivation (SD and its relationships with clinical features. Methods: Twelve healthy male subjects underwent resting-state functional magnetic resonance imaging twice: once following rested wakefulness (RW and the other following 72 hours of total SD. Before the scans, all subjects underwent the attention network test (ANT. The independent component analysis (ICA, rsFC, and ALFF methods were used to examine intrinsic DMN impairment. Receiver operating characteristic (ROC curve was used to distinguish SD status from RW status. Results: Compared with RW subjects, SD subjects showed a lower accuracy rate (RW =96.83%, SD =77.67%; P<0.001, a slower reaction time (RW =695.92 ms; SD =799.18 ms; P=0.003, a higher lapse rate (RW =0.69%, SD =19.29%; P<0.001, and a higher intraindividual coefficient of variability in reaction time (RW =0.26, SD =0
Keskin, Necla; Tamam, Lut; Ozpoyraz, Nurgul
Sleep quality is affected in bipolar disorder even in euthymic episodes. The aim of this study was to assess sleep quality in bipolar euthymic patients, determine related clinical characteristics and evaluate its effects on functionality. A total of 122 outpatients were included. Scales were used to confirm that patients were euthymic. Mini Mental Test was performed to exclude patients with a diagnosis of dementia. A data form for socio-demographic features and clinical characteristics of bipolar disorder have been completed. SCID-I and SCID II were used. The general features of sleep were investigated by General Sleep Questionnaire. All patients completed Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and Bipolar Disorder Functioning Questionnaire. 56.5% of our sample had poor sleep quality. Patients with poor sleep had a longer time to fall asleep and more frequent waking after sleep onset. Caffeine use and smoking, history of suicide attempts, seasonality, comorbidity of lifetime anxiety, somatoform and impulse control disorders, using antidepressant medication and administration of electroconvulsive therapy were significantly higher; emotional and intellectual functioning, household relations, taking initiative, self-sufficiency and total functionality were lower in bipolar patients with poor sleep quality (p<0.05). The strongest predictor of sleep quality problem was seasonality, recording an odds ratio of 3.91. Sleep quality is closely related with clinical features of bipolar disorder. Sleep quality is affected negatively in euthymic episodes of bipolar disorder and poor sleep quality cause loss in functionality. Assessment of sleep disturbances routinely in psychiatric interviews and dealing with sleep problems regardless mood episodes may improve sleep quality, thereby functionality and quality of life. Copyright © 2017 Elsevier Inc. All rights reserved.
Choi, Su Jung; Suh, Sooyeon; Ong, Jason; Joo, Eun Yeon
To investigate whether sleep perception (SP), defined by the ratio of subjective and objective total sleep time, and habitual sleep time in various sleep disorders may be based on comorbid insomnia status. We enrolled 420 patients (age 20-79 y) who underwent polysomnography (PSG). They were divided into three groups based on chief complaints: chronic insomnia (CI, n = 69), patients with both obstructive sleep apnea and insomnia (OSA-I, n = 49) or OSA only (OSA, n = 149). Healthy volunteers were also recruited (normal controls [NC], n = 80). We compared differences in PSG parameters and habitual sleep duration and investigated the discrepancy between objective and subjective total sleep time (TST) and sleep latency among four groups. Subjective TST was defined as sleep time perceived by participants the next morning of PSG. SP for TST was highest in the OSA group (median 92.9%), and lowest in the CI group (80.3%). SP of the NC group (91.4%) was higher than the CI, but there was no difference between OSA-I and OSA groups. OSA-I had higher depressive mood compared to the OSA group (p insomnia and arousal index of PSG. Insomnia patients with (OSA-I) or without OSA (CI) reported the smallest discrepancy between habitual sleep duration and objective TST. Patients with OSA with or without insomnia have different PSG profiles, which suggests that objective measures of sleep are an important consideration for differentiating subtypes of insomnia and tailoring proper treatment. A commentary on this articles appears in this issue on page 1437. © 2016 American Academy of Sleep Medicine
Chatterjee, Abhishek; Holubar, Stefan D; Figy, Sean; Chen, Lilian; Montagne, Shirley A; Rosen, Joseph M; Desimone, Joseph P
The relative value unit system relies on subjective measures of physician input in the care of patients. A payment per unit time model incorporates surgeon reimbursement to the total care time spent in the operating room, postoperative in-house, and clinic time to define payment per unit time. We aimed to compare common general surgery operations by using the total care time and payment per unit time method in order to demonstrate a more objective measurement for physician reimbursement. Average total physician payment per case was obtained for 5 outpatient operations and 4 inpatient operations in general surgery. Total care time was defined as the sum of operative time, 30 minutes per hospital day, and 30 minutes per office visit for each operation. Payment per unit time was calculated by dividing the physician reimbursement per case by the total care time. Total care time, physician payment per case, and payment per unit time for each type of operation demonstrated that an average payment per time spent for inpatient operations was $455.73 and slightly more at $467.51 for outpatient operations. Partial colectomy with primary anastomosis had the longest total care time (8.98 hours) and the least payment per unit time ($188.52). Laparoscopic gastric bypass had the highest payment per time ($707.30). The total care time and payment per unit time method can be used as an adjunct to compare reimbursement among different operations on an institutional level as well as on a national level. Although many operations have similar payment trends based on time spent by the surgeon, payment differences using this methodology are seen and may be in need of further review. Copyright © 2012 American College of Surgeons. Published by Elsevier Inc. All rights reserved.
Bertisch, Suzanne M; Pollock, Benjamin D; Mittleman, Murray A; Buysse, Daniel J; Bazzano, Lydia A; Gottlieb, Daniel J; Redline, Susan
To quantify the association between insomnia/poor sleep with objective short sleep and incident cardiovascular disease (CVD) and mortality in the general population. We conducted a time-to-event analysis of Sleep Heart Health Study data. Questionnaires and at-home polysomnography were performed between 1994 -1998. Participants were followed for a median 11.4 years (Q1-Q3, 8.8-12.4 years) until death or last contact. The primary exposure was insomnia or poor sleep with short sleep defined as: difficulty falling asleep, difficulty returning to sleep, early morning awakenings, or sleeping pill use, 16-30 nights/month; and total sleep insomnia/poor sleep with short sleep and CVD, as well as all-cause mortality. Among 4,994 participants (mean age 64.0 ± 11.1 years), 14.1% reported insomnia or poor sleep, of which 50.3% slept insomnia/poor sleep with short sleep group compared with the reference group (HR, 1.29, 95% CI, 1.00, 1.66), but neither the insomnia/poor sleep only nor short sleep only groups were associated with higher incident CVD. Insomnia/poor sleep with objective short sleep was not significantly associated with all-cause mortality (HR, 1.07, 95% CI, 0.86, 1.33). Insomnia/poor sleep with PSG-short sleep was associated with higher risk of incident CVD. Future studies should evaluate the impact of interventions to improve insomnia with PSG-short sleep on CVD.
Chang, Anne-Marie; Aeschbach, Daniel; Duffy, Jeanne F; Czeisler, Charles A
In the past 50 y, there has been a decline in average sleep duration and quality, with adverse consequences on general health. A representative survey of 1,508 American adults recently revealed that 90% of Americans used some type of electronics at least a few nights per week within 1 h before bedtime. Mounting evidence from countries around the world shows the negative impact of such technology use on sleep. This negative impact on sleep may be due to the short-wavelength-enriched light emitted by these electronic devices, given that artificial-light exposure has been shown experimentally to produce alerting effects, suppress melatonin, and phase-shift the biological clock. A few reports have shown that these devices suppress melatonin levels, but little is known about the effects on circadian phase or the following sleep episode, exposing a substantial gap in our knowledge of how this increasingly popular technology affects sleep. Here we compare the biological effects of reading an electronic book on a light-emitting device (LE-eBook) with reading a printed book in the hours before bedtime. Participants reading an LE-eBook took longer to fall asleep and had reduced evening sleepiness, reduced melatonin secretion, later timing of their circadian clock, and reduced next-morning alertness than when reading a printed book. These results demonstrate that evening exposure to an LE-eBook phase-delays the circadian clock, acutely suppresses melatonin, and has important implications for understanding the impact of such technologies on sleep, performance, health, and safety.
de Godoy, Luciana Balester Mello; Luz, Gabriela Pontes; Palombini, Luciana Oliveira; E Silva, Luciana Oliveira; Hoshino, Wilson; Guimarães, Thaís Moura; Tufik, Sergio; Bittencourt, Lia; Togeiro, Sonia Maria
To compare sleep quality and sustained attention of patients with Upper Airway Resistance Syndrome (UARS), mild Obstructive Sleep Apnea (OSA) and normal individuals. UARS criteria were presence of excessive daytime sleepiness (Epworth Sleepiness Scale-ESS-≥ 10) and/or fatigue (Modified Fatigue Impact Scale-MFIS-≥ 38) associated to Apnea/hypopnea index (AHI) ≤ 5 and Respiratory Disturbance Index (RDI) > 5 events/hour of sleep or more than 30% of total sleep time with flow limitation. Mild OSA was considered if the presence of excessive daytime sleepiness (ESS ≥ 10) and/or fatigue (MFIS ≥ 38) associated to AHI ≥ 5 and ≤ 15 events/hour. "Control group" criteria were AHI sleep, clinical, neurological or psychiatric disorder. 115 individuals (34 UARS and 47 mild OSA patients and 34 individuals in "control group"), adjusted for age, gender, body mass index (BMI) and schooling years, performed sleep questionnaires and sustained attention evaluation. Psychomotor Vigilance Task (PVT) was performed five times (each two hours) from 8 a.m. to 4 p.m. UARS patients had worse sleep quality (Functional Outcomes of Sleep Questionnaire-FOSQ-and Pittsburgh Sleep Quality Index-PSQI: p sleep quality, more fatigue and a worse early morning sustained attention compared to mild OSA. These last had a worse sustained attention than controls.
Hirscher, Verena; Unbehaun, Thomas; Feige, Bernd; Nissen, Christoph; Riemann, Dieter; Spiegelhalder, Kai
The validity of sleep laboratory investigations in patients with insomnia is important for researchers and clinicians. The objective of this study was to examine the first-night effect and the reverse first-night effect in patients with chronic primary insomnia compared with good sleeper controls. A retrospective comparison of a well-characterised sample of 50 patients with primary insomnia and 50 good sleeper controls was conducted with respect to 2 nights of polysomnography, and subjective sleep parameters in the sleep laboratory and the home setting. When comparing the first and second sleep laboratory night, a significant first-night effect was observed across both groups in the great majority of the investigated polysomnographic and subjective variables. However, patients with primary insomnia and good sleeper controls did not differ with respect to this effect. Regarding the comparison between the sleep laboratory nights and the home setting, unlike good sleeper controls, patients with primary insomnia reported an increased subjective sleep efficiency on both nights (in part due to a reduced bed time) and an increased subjective total sleep time on the second night. These results suggest that even the second sleep laboratory night does not necessarily provide clinicians and researchers with a representative insight into the sleep perception of patients with primary insomnia. Future studies should investigate whether these findings also hold for other patient populations. © 2015 European Sleep Research Society.
Haynes, Patricia L; Bootzin, Richard R; Smith, Leisha; Cousins, Jennifer; Cameron, Michael; Stevens, Sally
To examine whether change in total sleep time during an integrative, behavioral sleep intervention is associated with aggression. Specifically, we tested whether adolescents who reported experiencing aggressive thoughts or actions after treatment had worse treatment trajectories (e.g., less total sleep time across treatment) than adolescents with no aggressive thoughts or actions after treatment. Nonpharmacologic open trial with 9 weeks of weekly assessment. University of Arizona Sleep Research Laboratory Twenty-three adolescents recently treated for substance abuse in outpatient community centers. Six-week integrative, behavioral sleep intervention. Weekly sleep-summary indexes were calculated from daily sleep diaries and entered as dependent variables in a series of growth-curve analyses. Statistically significant Session x Post-treatment Aggressive Ideation interactions emerged when predicting changes in total sleep time, gamma13 = 9.76 (SE = 4.12), p aggressive ideation and the frequency of substance use, as assessed at baseline. A similar pattern of results was seen for self-reported aggressive actions occurring during conflicts. These pilot data suggest that inadequate sleep in substance-abusing adolescents may contribute to the experiencing of aggressive thoughts and actions. Limitations include a small sample size and a restricted assessment of aggression. Nonetheless, these findings lend preliminary support to the breadth of therapeutic effectiveness of an integrative, behavioral sleep-therapy program for adolescents with a history of substance abuse and related behaviors.
Della Monica, Ciro; Atzori, Giuseppe; Dijk, Derk-Jan
Recently, evidence has emerged that the phases of the moon may modulate subjective sleep quality and polysomnographically assessed sleep structure in humans. We aimed to explore further the putative effects of circa-lunar periodicity (~29.5 days) on subjective and objective parameters of human sleep in a retrospective analysis. The baseline sleep recordings of 205 (91 males and 114 females; mean age = 47.47 years, standard deviation =19.01; range: 20-84 years) healthy and carefully screened participants who participated in two clinical trials in the Surrey Clinical Research Centre were included in the analyses. Sleep was recorded in windowless sleep laboratories. For each study night, we calculated the distance, in days, to the date of the closest full moon phase and based on this distance, classified sleep records in three lunar classes. Univariate analysis of variance with factors lunar class, age and sex was applied to each of 21 sleep parameters. No significant main effect for the factor lunar class was observed for any of the objective sleep parameters and subjective sleep quality but some significant interactions were observed. The interaction between lunar class and sex was significant for total sleep time, Stage 4 sleep and rapid eye movement (REM) sleep. Separate analyses for men and women indicated that in women total sleep time, Stage 4 sleep and REM sleep were reduced when sleep occurred close to full moon, whereas in men REM duration increased around full moon. These data provide limited evidence for an effect of lunar phase on human sleep. © 2015 European Sleep Research Society.
Bathgate, Christina J; Edinger, Jack D; Wyatt, James K; Krystal, Andrew D
To examine the relationship between hypertension prevalence in individuals with insomnia who have short total sleep duration insomnia disorder (MAge = 46.2 y, SDAge = 13.7 y) participated in this study at two large university medical centers. Two nights of polysomnography, 2 w of sleep diaries, questionnaires focused on sleep, medical, psychological, and health history, including presence/absence of hypertension were collected. Logistic regressions assessed the odds ratios of hypertension among persons with insomnia with short sleep duration insomnia with a sleep duration ≥ 6 h, measured both objectively and subjectively. Consistent with previous studies using objective total sleep duration, individuals with insomnia and short sleep duration insomnia with sleep duration ≥ 6 h. Increased risk for hypertension was independent of major confounding factors frequently associated with insomnia or hypertension. No significant risk was observed using subjectively determined total sleep time groups. Receiver operating characteristic curve analysis found that the best balance of sensitivity and specificity using subjective total sleep time was at a 6-h cutoff, but the area under the receiver operating characteristic curve showed low accuracy and did not have good discriminant value. Objectively measured short sleep duration increased the odds of reporting hypertension more than threefold after adjusting for potential confounders; this relationship was not significant for subjectively measured sleep duration. This research supports emerging evidence that insomnia with objective short sleep duration is associated with an increased risk of comorbid hypertension. © 2016 Associated Professional Sleep Societies, LLC.
Full Text Available Alexandra K Gold,1 Louisa G Sylvia,1,2 1Department of Psychiatry, Massachusetts General Hospital, 2Harvard Medical School, Boston, MA, USA Abstract: Bipolar disorder is a serious mental illness characterized by alternating periods of elevated and depressed mood. Sleep disturbances in bipolar disorder are present during all stages of the condition and exert a negative impact on overall course, quality of life, and treatment outcomes. We examine the partnership between circadian system (process C functioning and sleep–wake homeostasis (process S on optimal sleep functioning and explore the role of disruptions in both systems on sleep disturbances in bipolar disorder. A convergence of evidence suggests that sleep problems in bipolar disorder result from dysregulation across both process C and process S systems. Biomarkers of depressive episodes include heightened fragmentation of rapid eye movement (REM sleep, reduced REM latency, increased REM density, and a greater percentage of awakenings, while biomarkers of manic episodes include reduced REM latency, greater percentage of stage I sleep, increased REM density, discontinuous sleep patterns, shortened total sleep time, and a greater time awake in bed. These findings highlight the importance of targeting novel treatments for sleep disturbance in bipolar disorder. Keywords: bipolar disorder, circadian rhythms, sleep–wake homeostasis
Quach, Jon; Price, Anna M H; Bittman, Michael; Hiscock, Harriet
The aim of this study is to use national Australian time-diary data to examine both (1) cross-sectionally and (2) longitudinally whether being late versus early to sleep or wake is associated with poorer child behavior, quality of life, learning, cognition and weight status, and parental mental health. Data from the first three waves of the Longitudinal Study of Australian Children were taken. A national representative sample of 4983 4-5-year-olds, recruited in 2004 from the Australian Medicare database and followed up biennially, was taken; 3631 had analyzable sleep information and a concurrent measure of health and well-being for at least one wave. Parents completed 24-h child time-use diaries for one week and one weekend day at each wave. Using median splits, sleep timing was categorized into early-to-sleep/early-to-wake (EE), early-to-sleep/late-to-wake (EL), late-to-sleep/early-to-wake (LE), and late-to-sleep/late-to-wake (LL) at each wave. The outcomes included parent-reported child behavior, health-related quality of life, maternal/paternal mental health, teacher-reported child language, literacy, mathematical thinking, and approach to learning. The study assessed child body mass index and girth. (1) Using EE as the comparator, linear regression analyses revealed that being late-to-sleep was associated with poorer child quality of life from 6 to 9 years and maternal mental health at 6-7 years. There was inconsistent or no evidence for associations between sleep timing and all other outcomes. (2) Using the count of the number of times (waves) at which a child was categorized as late-to-sleep (range 0-3), longitudinal analyses demonstrated that there was a cumulative effect of late-to-sleep profiles on poorer child and maternal outcomes at the child age of 8-9 years. Examined cross-sectionally, sleep timing is a driver of children's quality of life and maternal depression. Examined longitudinally, there appears to be cumulative and adverse relationships
Berger, Ann M; VonEssen, Susanna; Khun, Brett R; Piper, Barbara F; Farr, Lynne; Agrawal, Sangeeta; Lynch, James C; Higginbotham, Patti
To evaluate the feasibility of an intervention designed to promote sleep and modify fatigue during four cycles of adjuvant breast cancer chemotherapy. Prospective, repeated measures, quasi-experimental feasibility study. Midwestern urban oncology clinics. 25 women between the ages of 40-65 (mean = 54.3) with stage I-II breast cancer receiving doxorubicin-based chemotherapy. Each woman developed, reinforced, and revised an individualized sleep promotion plan (ISPP) with four components: sleep hygiene, relaxation therapy, stimulus control, and sleep restriction techniques. A daily diary, the Pittsburgh Sleep Quality Index, a wrist actigraph, and the Piper Fatigue Scale were used to collect data two days before and seven days after each treatment. Adherence, sleep and wake outcomes, and fatigue. Adherence rates with the components of the ISPP varied during treatments one through four: sleep hygiene (68%-78%), relaxation therapy (57%-67%), stimulus control (46%-67%), and sleep restriction (76%-80%). Mean sleep and wake outcomes at baseline, peak, and rebound times were that (a) sleep latency remained brief (less than 30 minutes per night), (b) time awake after sleep onset exceeded the desired less than 30 minutes per night, (c) sleep efficiency scores remained stable at 85%-90%, (d) total rest time remained stable at 8-10 hours per night, (e) subjective ratings of feelings on arising were stable, and (f) nighttime awakenings were 8-10 per night. Fatigue outcomes were that fatigue was stable two days after each treatment and mean daily fatigue intensity was lower at treatment three than at treatment one but rebounded at treatment four. The intervention was feasible, adherence rates improved over time, and most sleep and wake patterns were consistent with normal values. Revisions will focus on decreasing nighttime awakenings. Adopting behaviors to promote sleep may assist in maintaining sleep and managing fatigue during chemotherapy.
Saadat, Haleh; Bissonnette, Bruno; Tumin, Dmitry; Thung, Arlyne; Rice, Julie; Barry, N'Diris; Tobias, Joseph
A physician's fatigue raises significant concerns regarding personal and patient safety. Effects of sleep deprivation on clinical performance and the quality of patient care are major considerations of today's health care environment. To evaluate the impact of partial sleep deprivation after a 17-h overnight call (3 pm-7 am) on the mood status and cognitive skills of anesthesiologists in an academic clinical hospital setting, as compared to these parameters during regular working hours. Taking circadian rhythm into account, the following measures were assessed in 21 pediatric anesthesiologists at two time points over the course of the study; (i) between 7 and 8 am on a regular non call day, and (ii) between 7 and 8 am after a 17-h in-house call (3 pm-7 am). Six mood states were assessed using the Profile of Mood States. A Total Mood Disturbance (TMD) score was obtained as the sum of all mood scores minus vigor. The total score provides a global estimate of affective state. Simple cognitive tests were similarly administered to assess cognitive skills. A two-tailed paired t-test was used to compare data between regular and post call days. A P sleep deprivation affects the total mood status of anesthesiologists and impacts their cognitive skills. These findings are particularly relevant in a context of increased work expectation, particularly on clinical performance in our modern medical system. Such observations suggest that there may be changes that impact the safety of our patients and the quality of health care that is provided. © 2015 John Wiley & Sons Ltd.
Dubowy, Christine; Moravcevic, Katarina; Yue, Zhifeng; Wan, Joy Y; Van Dongen, Hans P A; Sehgal, Amita
thermogenetic sleep deprivation. Neither of the two genotypes has reduced total baseline sleep. Statistical analysis across all screened lines shows that genotype is a strong predictor of recovery sleep, independent from effects of genotype on baseline sleep. Our data show that rebound sleep following thermogenetic sleep deprivation can be genetically separated from sleep at baseline. This suggests that genetically controlled mechanisms of sleep regulation not manifest under undisturbed conditions contribute to sleep rebound following thermogenetic sleep deprivation. © 2016 Associated Professional Sleep Societies, LLC.
Bei, Bei; Seeman, Teresa E; Carroll, Judith E; Wiley, Joshua F
Variable daily sleep (ie, higher intraindividual variability; IIV) is associated with negative health consequences, but potential physiological mechanisms are poorly understood. This study examined how the IIV of sleep timing, duration, and quality is associated with physiological dysregulation, with diurnal cortisol trajectories as a proximal outcome and allostatic load (AL) as a multisystem distal outcome. Participants are 436 adults (Mage ± standard deviation = 54.1 ± 11.7, 60.3% women) from the Midlife in the United States study. Sleep was objectively assessed using 7-day actigraphy. Diurnal cortisol was measured via saliva samples (four/day for 4 consecutive days). AL was measured using 23 biomarkers from seven systems (inflammatory, hypothalamic-pituitary-adrenal axis, metabolic glucose and lipid, cardiovascular, parasympathetic, sympathetic) using a validated bifactor model. Linear and quadratic effects of sleep IIV were estimated using a validated Bayesian model. Controlling for covariates, more variable sleep timing (p = .04 for risetime, p = .097 for bedtime) and total sleep time (TST; p = .02), but not mean sleep variables, were associated with flatter cortisol diurnal slope. More variable sleep onset latency and wake after sleep onset, later average bedtime, and shorter TST were associated with higher AL adjusting for age and sex (p-values sleep patterns were associated with blunted diurnal cortisol trajectories but not with higher multisystem physiological dysregulation. The associations between sleep IIV and overall health are likely complex, including multiple biopsychosocial determinants and require further investigation. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail email@example.com.
Cobabe, Maurine M; Sessler, Daniel I; Nowacki, Amy S; O'Rourke, Colin; Andrews, Noah; Foldvary-Schaefer, Nancy
Prolonged sleep deprivation activates epileptiform EEG abnormalities and seizures in people with epilepsy. Few studies have addressed the effect of chronic partial sleep deprivation on seizure occurrence in populations with epilepsy. We tested the primary hypothesis that partial sleep deprivation over 24- and 72-hour periods increases seizure occurrence in adults with epilepsy. Forty-four subjects completed a series of self-reported instruments, as well as 1-month sleep and seizure diaries, to characterize their sleep and quality of life. Diaries were used to determine the relationship between seizure occurrence and total sleep time 24 and 72h before seizure occurrence using random effects models and a logistic regression model fit by generalized estimating equations. A total of 237 seizures were recorded during 1295 diary days, representing 5.5±7.0 (mean±SD) seizures per month. Random effects models for 24- and 72-hour total sleep times showed no clinically or statistically significant differences in the total sleep time between preseizure periods and seizure-free periods. The average 24-hour total sleep time during preseizure 24-hour periods was 8min shorter than that during seizure-free periods (p=0.51). The average 72-hour total sleep time during preseizure periods was 20min longer than that during seizure-free periods (p=0.86). The presence of triggers was a significant predictor of seizure occurrence, with stress/anxiety noted most often as a trigger. Mean total sleep time was 9h, and subjects took an average of 12±10 naps per month, having a mean duration of 1.9±1.2h. Daytime sleepiness, fatigue, and insomnia symptoms were commonly reported. Small degrees of sleep loss were not associated with seizure occurrence in our sample of adults with epilepsy. Our results also include valuable observations of the altered sleep times and frequent napping habits of adults with refractory epilepsy and the potential contribution of these habits to quality of life and
Bassett, Sarah M; Lupis, Sarah B; Gianferante, Danielle; Rohleder, Nicolas; Wolf, Jutta M
Given the well-documented deleterious health effects, poor sleep has become a serious public health concern and increasing efforts are directed toward understanding underlying pathways. One potential mechanism may be stress and its biological correlates; however, studies investigating the effects of poor sleep on a body's capacity to deal with challenges are lacking. The current study thus aimed at testing the effects of sleep quality and quantity on cortisol responses to acute psychosocial stress. A total of 73 college-aged adults (44 females) were investigated. Self-reported sleep behavior was assessed via the Pittsburgh Sleep Quality Index and salivary cortisol responses to the Trier Social Stress Test were measured. In terms of sleep quality, we found a significant three-way interaction, such that relative to bad sleep quality, men who reported fairly good or very good sleep quality showed blunted or exaggerated cortisol responses, respectively, while women's stress responses were less dependent on their self-reported sleep quality. Contrarily, average sleep duration did not appear to impact cortisol stress responses. Lastly, participants who reported daytime dysfunctions (i.e. having trouble staying awake or keeping up enthusiasm) also showed a trend to blunted cortisol stress responses compared to participants who did not experience these types of daytime dysfunctions. Overall, the current study suggests gender-specific stress reactivity dysfunctions as one mechanism linking poor sleep with detrimental physical health outcomes. Furthermore, the observed differential sleep effects may indicate that while the body may be unable to maintain normal hypothalamic-pituitary-adrenal functioning in an acute psychosocial stress situation after falling prey to low sleep quality, it may retain capacities to deal with challenges during extended times of sleep deprivation.
Kirby, Matthew; Maggi, Stefania; D'Angiulli, Amedeo
The authors have integrated the major findings on the sleep-wake cycle and its performance correlates in adolescents. Basic research shows that lack of synchronicity between early school start times and the circadian rhythm of adolescents (and the sleep debt accumulated as a result) involves several cognitive correlates that may harm the academic…
Anouk A. M. T. Donners
Full Text Available Reduced immune functioning may have a negative impact on sleep and health, and vice versa. A survey among Dutch young adults (18–35 years old was administered to collect information on perception of reduced immunity and its relationship to sleep disorders, sleep duration, and quality. Sleep disorders were assessed with the SLEEP-50 questionnaire subscales of sleep apnea, insomnia, circadian rhythm disorder, and daily functioning. Dutch young adults (N = 574 completed the survey. Among them, subjects (N = 209; 36.4% reported perceived reduced immunity. Relative to those with a normal immune status, subjects reporting reduced immunity had significantly higher scores (p=0.0001 on sleep apnea (2.6 versus 3.6, insomnia (5.1 versus 6.8, and circadian rhythm disorder (2.1 versus 2.7. Subjects reporting reduced immunity also had significantly poorer daily functioning scores (5.4 versus 7.6, p=0.0001. No differences were observed in total sleep time, but those reporting reduced immunity had significantly poorer ratings of sleep quality (6.8 versus 7.2, p=0.0001. Our findings suggest that perceived reduced immunity is associated with sleep disturbances, impaired daily functioning, and a poorer sleep quality. Experimental studies including the assessment of immune biomarkers and objective measures of sleep (polysomnography should confirm the current observations.
Adrian A. Ong
Full Text Available Objective: To review and assess the current selection of sleep analysis smartphone applications (apps available for download. Methods: The iOS and Google Play mobile app store were searched for sleep analysis apps targeted for consumer use. Alarm clock, sleep-aid, snoring and sleep-talking recorder, fitness tracker apps, and apps geared towards health professionals were excluded. App information and features were obtained from in-store descriptions, and the app developer website. Results: A total of 51 unique sleep apps in both iOS and Google Play stores were included. The apps were rated 3.8/5 in both stores, and had an average price of $1.12 in the iOS store and $0.58 in the Google Play store. >65% of sleep apps report on sleep structure, including duration, time awake, and time in light/deep sleep, while reporting of REM was limited. The availability of extra features was variable, ranging from 4% to 73% of apps. Conclusions: There are a variety of sleep analysis apps with a range of functionality. The apps with the most reviews from the each store are featured. Many apps provide data on sleep structure; however the algorithms are not validated by scientific literature or studies. Since patients may inquire about their sleep habits from these apps, it is necessary for physicians to be aware of the most common apps and the features offered and their limitations in order to properly counsel patients. Keywords: Mobile applications, Smartphone, Apps, Sleep monitor, Actigraphy
Burgess, Helen J; Park, Margaret; Wyatt, James K; Rizvydeen, Muneer; Fogg, Louis F
To compare sleep and circadian variability in adults with delayed sleep-wake phase disorder (DSWPD) to healthy controls. Forty participants (22 DSWPD, 18 healthy controls) completed a ten-day protocol, consisting of DLMO assessments on two consecutive nights, a five-day study break, followed by two more DLMO assessments. All participants were instructed to sleep within one hour of their self-reported average sleep schedule for the last four days of the study break. We analyzed the participants' wrist actigraphy data during these four days to examine intraindividual variability in sleep timing, duration and efficiency. We also examined shifts in the DLMO from before and after the study break. Under the same conditions, people with DSWPD had significantly more variable wake times and total sleep time than healthy controls (p ≤ 0.015). Intraindividual variability in sleep onset time and sleep efficiency was similar between the two groups (p ≥ 0.30). The DLMO was relatively stable across the study break, with only 11% of controls but 27% of DSWPDs showed more than a one hour shift in the DLMO. Only in the DSWPD sample was greater sleep variability associated with a larger shift in the DLMO (r = 0.46, p = 0.03). These results suggest that intraindividual variability in sleep can be higher in DSWPD versus healthy controls, and this may impact variability in the DLMO. DSWPD patients with higher intraindividual variability in sleep are more likely to have a shifting DLMO, which could impact sleep symptoms and the optimal timing of light and/or melatonin treatment for DSWPD. Circadian Phase Assessments at Home, http://clinicaltrials.gov/show/NCT01487252, NCT01487252. Copyright © 2017 Elsevier B.V. All rights reserved.
Eliasson, Arne H; Lettieri, Christopher J; Eliasson, Arn H
Prior studies have placed emphasis on the need for adequate total sleep time for student performance. We sought to investigate the relative importance of total sleep time compared to the timing of sleep and wakefulness for academic performance. We performed a questionnaire-based survey of college students in October 2007. The questionnaire gathered detailed information on sleep habits including naps, reasons for missing sleep, academic performance, study habits, time spent working outside of school, and stimulant use. Compared to those with the lowest academic performance, students with the highest performance had significantly earlier bedtimes (p = 0.05) and wake times (p = 0.008). Napping tended to be more common among high performers (p = 0.07). Of importance, there were no significant differences in total sleep time with or without naps, weekend sleep habits, study time, gender, race, reasons for staying up at night, nor in use of caffeinated beverages, over-the-counter stimulant pills, or use of prescription stimulants. Timing of sleep and wakefulness correlated more closely with academic performance than total sleep time and other relevant factors. These findings have important implications for programs intended to improve academic performance by targeting sleep habits of students.
Peiró-Velert, Carmen; Valencia-Peris, Alexandra; González, Luis M; García-Massó, Xavier; Serra-Añó, Pilar; Devís-Devís, José
Screen media usage, sleep time and socio-demographic features are related to adolescents' academic performance, but interrelations are little explored. This paper describes these interrelations and behavioral profiles clustered in low and high academic performance. A nationally representative sample of 3,095 Spanish adolescents, aged 12 to 18, was surveyed on 15 variables linked to the purpose of the study. A Self-Organizing Maps analysis established non-linear interrelationships among these variables and identified behavior patterns in subsequent cluster analyses. Topological interrelationships established from the 15 emerging maps indicated that boys used more passive videogames and computers for playing than girls, who tended to use mobile phones to communicate with others. Adolescents with the highest academic performance were the youngest. They slept more and spent less time using sedentary screen media when compared to those with the lowest performance, and they also showed topological relationships with higher socioeconomic status adolescents. Cluster 1 grouped boys who spent more than 5.5 hours daily using sedentary screen media. Their academic performance was low and they slept an average of 8 hours daily. Cluster 2 gathered girls with an excellent academic performance, who slept nearly 9 hours per day, and devoted less time daily to sedentary screen media. Academic performance was directly related to sleep time and socioeconomic status, but inversely related to overall sedentary screen media usage. Profiles from the two clusters were strongly differentiated by gender, age, sedentary screen media usage, sleep time and academic achievement. Girls with the highest academic results had a medium socioeconomic status in Cluster 2. Findings may contribute to establishing recommendations about the timing and duration of screen media usage in adolescents and appropriate sleep time needed to successfully meet the demands of school academics and to improve
Full Text Available Screen media usage, sleep time and socio-demographic features are related to adolescents' academic performance, but interrelations are little explored. This paper describes these interrelations and behavioral profiles clustered in low and high academic performance. A nationally representative sample of 3,095 Spanish adolescents, aged 12 to 18, was surveyed on 15 variables linked to the purpose of the study. A Self-Organizing Maps analysis established non-linear interrelationships among these variables and identified behavior patterns in subsequent cluster analyses. Topological interrelationships established from the 15 emerging maps indicated that boys used more passive videogames and computers for playing than girls, who tended to use mobile phones to communicate with others. Adolescents with the highest academic performance were the youngest. They slept more and spent less time using sedentary screen media when compared to those with the lowest performance, and they also showed topological relationships with higher socioeconomic status adolescents. Cluster 1 grouped boys who spent more than 5.5 hours daily using sedentary screen media. Their academic performance was low and they slept an average of 8 hours daily. Cluster 2 gathered girls with an excellent academic performance, who slept nearly 9 hours per day, and devoted less time daily to sedentary screen media. Academic performance was directly related to sleep time and socioeconomic status, but inversely related to overall sedentary screen media usage. Profiles from the two clusters were strongly differentiated by gender, age, sedentary screen media usage, sleep time and academic achievement. Girls with the highest academic results had a medium socioeconomic status in Cluster 2. Findings may contribute to establishing recommendations about the timing and duration of screen media usage in adolescents and appropriate sleep time needed to successfully meet the demands of school academics and
Kalenkoski, Charlene Marie; Wulff Pabilonia, Sabrina
We use detailed time-diary information on high school students’ daily activities from the 2003–2008 American Time Use Surveys (ATUS) to investigate the effects of employment on the time a student spends on homework and other major activities. Time-diary data are more detailed and accurate than data derived from responses to “usual activity” survey questions underlying other analyses and capture the immediate effects of working that may well accumulate over time to affect future outcomes. Our ...
Garcia, Alexandra N; Salloum, Ihsan M
In the United States, approximately 60 million Americans suffer from sleep disorders and about 22 million Americans report substance dependence or use disorders annually. Sleep disturbances are common consequences of substance use disorders and are likely found in primary care as well as in specialty practices. The aim of this review was to evaluate the effects of the most frequently used substances-nicotine, alcohol, opioids, cocaine, caffeine, and cannabis-have on sleep parameters measured by polysomnography (PSG) and related clinical manifestations. We used electronic databases such as PubMED and PsycINFO to search for relevant articles. We only included studies that assessed sleep disturbances using polysomnography and reviewed the effects of these substances on six clinically relevant sleep parameters: Total sleep time, sleep onset latency, rapid-eye movement, REM latency, wake after sleep onset, and slow wave sleep. Our review indicates that these substances have significant impact on sleep and that their effects differ during intoxication, withdrawal, and chronic use. Many of the substance-induced sleep disturbances overlap with those encountered in sleep disorders, medical, and psychiatric conditions. Sleep difficulties also increase the likelihood of substance use disorder relapse, further emphasizing the need for optimizing treatment interventions in these patients. Our review highlights the importance of systematically screening for substance use in patients with sleep disturbances and highlights the need for further research to understand mechanisms underlying substances-induced sleep disturbances and on effective interventions addressing these conditions. © American Academy of Addiction Psychiatry.
Videnovic, Aleksandar; Klerman, Elizabeth B; Wang, Wei; Marconi, Angelica; Kuhta, Teresa; Zee, Phyllis C
Impaired sleep and alertness are some of the most common nonmotor manifestations of Parkinson disease (PD) and currently have only limited treatment options. Light therapy (LT), a widely available treatment modality in sleep medicine, has not been systematically studied in the PD population. To determine the safety and efficacy of LT on excessive daytime sleepiness (EDS) associated with PD. This randomized, placebo-controlled, clinical intervention study was set in PD centers at Northwestern University and Rush University. Participants were 31 patients with PD receiving stable dopaminergic therapy with coexistent EDS, as assessed by an Epworth Sleepiness Scale score of 12 or greater, and without cognitive impairment or primary sleep disorder. Participants were randomized 1:1 to receive bright LT or dim-red LT (controlled condition) twice daily in 1-hour intervals for 14 days. This trial was conducted between March 1, 2007, and October 31, 2012. Data analysis of the intention-to-treat population was conducted from November 1, 2012, through April 30, 2016. The primary outcome measure was the change in the Epworth Sleepiness Scale score comparing the bright LT with the dim-red LT. Secondary outcome measures included the Pittsburgh Sleep Quality Index score, the Parkinson's Disease Sleep Scale score, the visual analog scale score for daytime sleepiness, and sleep log-derived and actigraphy-derived metrics. Among the 31 patients (13 males and 18 females; mean [SD] disease duration, 5.9 [3.6] years), bright LT resulted in significant improvements in EDS, as assessed by the Epworth Sleepiness Scale score (mean [SD], 15.81 [3.10] at baseline vs 11.19 [3.31] after the intervention). Both bright LT and dim-red LT were associated with improvements in sleep quality as captured by mean (SD) scores on the Pittsburg Sleep Quality Index (7.88 [4.11] at baseline vs 6.25 [4.27] after bright LT, and 8.87 [2.83] at baseline vs 7.33 [3.52] after dim-red LT) and the Parkinson's Disease
Wu, Ran; Wang, Guang-Hai; Zhu, Hong; Jiang, Fan; Jiang, Chun-Lei
This study aimed to (1) provide data on normal sleep patterns in Chinese preschool children, (2) identify cross-cultural differences of sleep patterns among children from China and other countries, (3) estimate the prevalence of sleep duration not meeting the optimal amount, and (4) characterize delayed weekend sleep pattern. A population-based sample of 1,610 children aged 3-6 years was recruited from 10 cities across China. Parents completed questions about their child's sleep patterns adapted from the Children's Sleep Habits Questionnaire (CSHQ). The mean bedtime was 9:31 PM, wake time was 7:27 AM, nighttime sleep duration was 9 hours 30 minutes, daytime sleep duration was 1 hour 31 minutes, and total sleep duration was 11 hours 2 minutes. The children had a shorter nighttime sleep duration but longer daytime naps, resulting in no differences in total sleep duration compared with counterparts predominantly in the west. Of the children, 85.3% met the recommended amount of sleep of 10 to 13 hours, and 10.8% slept fewer than 10 hours. The prevalence of sleep less than 10 hours was higher in older children and children from eastern China. Children went to bed and woke up more than 30 minutes later on weekends than weekdays, accounting for 40.1% and 50%, respectively. Children in western China showed longer delay than children in eastern China ( P < .05). Age- and region-specific variability of sleep patterns are reported as well as insufficient sleep and delayed weekend sleep pattern in Chinese preschool children. The cross-cultural difference of sleep patterns was in temporal placement rather than sleep duration. © 2018 American Academy of Sleep Medicine.
McCauley, Peter; Kalachev, Leonid V; Mollicone, Daniel J; Banks, Siobhan; Dinges, David F; Van Dongen, Hans P A
Recent experimental observations and theoretical advances have indicated that the homeostatic equilibrium for sleep/wake regulation--and thereby sensitivity to neurobehavioral impairment from sleep loss--is modulated by prior sleep/wake history. This phenomenon was predicted by a biomathematical model developed to explain changes in neurobehavioral performance across days in laboratory studies of total sleep deprivation and sustained sleep restriction. The present paper focuses on the dynamics of neurobehavioral performance within days in this biomathematical model of fatigue. Without increasing the number of model parameters, the model was updated by incorporating time-dependence in the amplitude of the circadian modulation of performance. The updated model was calibrated using a large dataset from three laboratory experiments on psychomotor vigilance test (PVT) performance, under conditions of sleep loss and circadian misalignment; and validated using another large dataset from three different laboratory experiments. The time-dependence of circadian amplitude resulted in improved goodness-of-fit in night shift schedules, nap sleep scenarios, and recovery from prior sleep loss. The updated model predicts that the homeostatic equilibrium for sleep/wake regulation--and thus sensitivity to sleep loss--depends not only on the duration but also on the circadian timing of prior sleep. This novel theoretical insight has important implications for predicting operator alertness during work schedules involving circadian misalignment such as night shift work.
Ng, Marcus; Pavlova, Milena
Since the formal characterization of sleep stages, there have been reports that seizures may preferentially occur in certain phases of sleep. Through ascending cholinergic connections from the brainstem, rapid eye movement (REM) sleep is physiologically characterized by low voltage fast activity on the electroencephalogram, REMs, and muscle atonia. Multiple independent studies confirm that, in REM sleep, there is a strikingly low proportion of seizures (~1% or less). We review a total of 42 distinct conventional and intracranial studies in the literature which comprised a net of 1458 patients. Indexed to duration, we found that REM sleep was the most protective stage of sleep against focal seizures, generalized seizures, focal interictal discharges, and two particular epilepsy syndromes. REM sleep had an additional protective effect compared to wakefulness with an average 7.83 times fewer focal seizures, 3.25 times fewer generalized seizures, and 1.11 times fewer focal interictal discharges. In further studies REM sleep has also demonstrated utility in localizing epileptogenic foci with potential translation into postsurgical seizure freedom. Based on emerging connectivity data in sleep, we hypothesize that the influence of REM sleep on seizures is due to a desynchronized EEG pattern which reflects important connectivity differences unique to this sleep stage.
Chung, Ka-Fai; Cheung, Miao-Miao
To determine sleep-wake patterns and evaluate sleep disturbance in Hong Kong adolescents; to identify factors that are associated with sleep disturbance; and to examine the relationship of sleep-wake variables and academic performance. A school-based cross-sectional survey. Sample included 1629 adolescents aged 12 to 19 years. Self-report questionnaires, including sleep-wake habit questionnaire, Sleep Quality Index, Morningness/ Eveningness scale, Epworth Sleepiness Scale, Perceived Stress Scale, academic performance, and personal data were administered. The average school-night bedtime was 23:24, and total sleep time was 7.3 hr. During weekends, the average bedtime and rise time was delayed by 64 min and 195 min, respectively. The prevalence of sleep disturbances occurring > or = 3 days per week in the preceding 3 months were: difficulty falling asleep (5.6%), waking up during the night (7.2%), and waking up too early in the morning (10.4%). The prevalence of > or = 1 of these three symptoms was 19.1%. Stepwise regression analyses revealed that circadian phase preference was the most significant predictor for school night bedtime, weekend oversleep, and daytime sleepiness. Perceived stress was the most significant risk factor for sleep disturbance. Students with marginal academic performance reported later bedtimes and shorter sleep during school nights, greater weekend delays in bedtime, and more daytime sleepiness than those with better grades. The prevalence of sleep deprivation and sleep disturbance among Hong Kong adolescents is comparable to those found in other countries. An intervention program for sleep problems in adolescents should be considered.
Philip, Pierre; Sagaspe, Patricia; Prague, Mélanie; Tassi, Patricia; Capelli, Aurore; Bioulac, Bernard; Commenges, Daniel; Taillard, Jacques
To evaluate the effects of acute sleep deprivation and chronic sleep restriction on vigilance, performance, and self-perception of sleepiness. Habitual night followed by 1 night of total sleep loss (acute sleep deprivation) or 5 consecutive nights of 4 hr of sleep (chronic sleep restriction) and recovery night. Eighteen healthy middle-aged male participants (age [(± standard deviation] = 49.7 ± 2.6 yr, range 46-55 yr). Multiple sleep latency test trials, Karolinska Sleepiness Scale scores, simple reaction time test (lapses and 10% fastest reaction times), and nocturnal polysomnography data were recorded. Objective and subjective sleepiness increased immediately in response to sleep restriction. Sleep latencies after the second and third nights of sleep restriction reached levels equivalent to those observed after acute sleep deprivation, whereas Karolinska Sleepiness Scale scores did not reach these levels. Lapse occurrence increased after the second day of sleep restriction and reached levels equivalent to those observed after acute sleep deprivation. A statistical model revealed that sleepiness and lapses did not progressively worsen across days of sleep restriction. Ten percent fastest reaction times (i.e., optimal alertness) were not affected by acute or chronic sleep deprivation. Recovery to baseline levels of alertness and performance occurred after 8-hr recovery night. In middle-aged study participants, sleep restriction induced a high increase in sleep propensity but adaptation to chronic sleep restriction occurred beyond day 3 of restriction. This sleepiness attenuation was underestimated by the participants. One recovery night restores daytime sleepiness and cognitive performance deficits induced by acute or chronic sleep deprivation. Philip P; Sagaspe P; Prague M; Tassi P; Capelli A; Bioulac B; Commenges D; Taillard J. Acute versus chronic partial sleep deprivation in middle-aged people: differential effect on performance and sleepiness. SLEEP 2012;35(7):997-1002.
... include being overweight and having a large neck. Losing even 10 percent of body weight can help reduce the number of times a person with sleep apnea stops breathing during sleep. African-Americans, Pacific ...
Castillo Escario, Y.; Blanco Almazan, D.; Camara Vazquez, M.A.; Jane Campos, R.
Obstructive sleep apnea (OSA) is a highly prevalent chronic disease, especially in elderly and obese population. Despite constituting a huge health and economic problem, most patients remain undiagnosed due to limitations in current strategies. Therefore, it is essential to find cost-effective diagnostic alternatives. One of these novel approaches is the analysis of acoustic snoring signals. Snoring is an early symptom of OSA which carries pathophysiological information of high diagnostic value. For this reason, the main objective of this work is to study the characteristics of single snores of different types, from healthy and OSA subjects. To do that, we analyzed snoring signals from previous databases and developed an experimental protocol to record simulated OSA-related sounds and characterize the response of two commercial tracheal microphones. Automatic programs for filtering, downsampling, event detection and time-frequency analysis were built in MATLAB. We found that time-frequency maps and spectral parameters (central, mean and peak frequency and energy in the 100-500 Hz band) allow distinguishing regular snores of healthy subjects from non-regular snores and snores of OSA subjects. Regarding the two commercial microphones, we found that one of them was a suitable snoring sensor, while the other had a too restricted frequency response. Future work shall include a higher number of episodes and subjects, but our study has contributed to show how important the differences between regular and non-regular snores can be for OSA diagnosis, and how much clinically relevant information can be extracted from time-frequency maps and spectral parameters of single snores. (Author)
Lockley, Steven W; Dressman, Marlene A; Licamele, Louis; Xiao, Changfu; Fisher, Dennis M; Flynn-Evans, Erin E; Hull, Joseph T; Torres, Rosarelis; Lavedan, Christian; Polymeropoulos, Mihael H
Most totally blind people have non-24-hour sleep-wake disorder (non-24), a rare circadian rhythm disorder caused by an inability of light to reset their circadian pacemaker. In two consecutive placebo-controlled trials (SET and RESET), we assessed safety and efficacy (in terms of circadian entrainment and maintenance) of once-daily tasimelteon, a novel dual-melatonin receptor agonist. We undertook the placebo-controlled, randomised, double-masked trials in 27 US and six German clinical research centres and sleep centres. We screened totally blind adults (18-75 years of age), who were eligible for the randomisation phase of SET if they had a non-24-hour circadian period (τ) of 24·25 h or longer (95% CI greater than 24·0 and up to 24·9 h), as calculated from measurements of urinary 6-sulphatoxymelatonin rhythms. For SET, we used block randomisation to assign patients (1:1) to receive tasimelteon (20 mg) or placebo every 24 h at a fixed clock time 1 h before target bedtime for 26 weeks. Patients who entered the open-label group receiving tasimelteon in SET or who did not meet the SET inclusion criteria but did meet the RESET inclusion criteria were screened for RESET. A subset of the patients who entered the open-label group before the RESET study and who had eligible τ values were screened for RESET after completing the open-label treatment. In RESET, we withdrew tasimelteon in a randomised manner (1:1) in patients who responded (ie, entrained) after a tasimelteon run-in period. Entrainment was defined as having τ of 24·1 h or less and a 95% CI that included 24·0 h. In SET, the primary endpoint was the proportion of entrained patients, assessed in the intention-to-treat population. The planned step-down primary endpoint assessed the proportion of patients who had a clinical response (entrainment at month 1 or month 7 plus clinical improvement, measured by the Non-24 Clinical Response Scale). In RESET, the primary endpoint was the proportion of non
Shochat, Tamar; Barker, David H; Sharkey, Katherine M; Van Reen, Eliza; Roane, Brandy M; Carskadon, Mary A
Depressive mood in youth has been associated with distinct sleep dimensions, such as timing, duration and quality. To identify discrete sleep phenotypes, we applied person-centred analysis (latent class mixture models) based on self-reported sleep patterns and quality, and examined associations between phenotypes and mood in high-school seniors. Students (n = 1451; mean age = 18.4 ± 0.3 years; 648 M) completed a survey near the end of high-school. Indicators used for classification included school night bed- and rise-times, differences between non-school night and school night bed- and rise-times, sleep-onset latency, number of awakenings, naps, and sleep quality and disturbance. Mood was measured using the total score on the Center for Epidemiologic Studies-Depression Scale. One-way anova tested differences between phenotype for mood. Fit indexes were split between 3-, 4- and 5-phenotype solutions. For all solutions, between phenotype differences were shown for all indicators: bedtime showed the largest difference; thus, classes were labelled from earliest to latest bedtime as 'A' (n = 751), 'B' (n = 428) and 'C' (n = 272) in the 3-class solution. Class B showed the lowest sleep disturbances and remained stable, whereas classes C and A each split in the 4- and 5-class solutions, respectively. Associations with mood were consistent, albeit small, with class B showing the lowest scores. Person-centred analysis identified sleep phenotypes that differed in mood, such that those with the fewest depressive symptoms had moderate sleep timing, shorter sleep-onset latencies and fewer arousals. Sleep characteristics in these groups may add to our understanding of how sleep and depressed mood associate in teens. © 2017 European Sleep Research Society.
Fuller, Kate L; Juliff, Laura; Gore, Christopher J; Peiffer, Jeremiah J; Halson, Shona L
Actical ® actigraphy is commonly used to monitor athlete sleep. The proprietary software, called Actiware ® , processes data with three different sleep-wake thresholds (Low, Medium or High), but there is no standardisation regarding their use. The purpose of this study was to examine validity and bias of the sleep-wake thresholds for processing Actical ® sleep data in team sport athletes. Validation study comparing actigraph against accepted gold standard polysomnography (PSG). Sixty seven nights of sleep were recorded simultaneously with polysomnography and Actical ® devices. Individual night data was compared across five sleep measures for each sleep-wake threshold using Actiware ® software. Accuracy of each sleep-wake threshold compared with PSG was evaluated from mean bias with 95% confidence limits, Pearson moment-product correlation and associated standard error of estimate. The Medium threshold generated the smallest mean bias compared with polysomnography for total sleep time (8.5min), sleep efficiency (1.8%) and wake after sleep onset (-4.1min); whereas the Low threshold had the smallest bias (7.5min) for wake bouts. Bias in sleep onset latency was the same across thresholds (-9.5min). The standard error of the estimate was similar across all thresholds; total sleep time ∼25min, sleep efficiency ∼4.5%, wake after sleep onset ∼21min, and wake bouts ∼8 counts. Sleep parameters measured by the Actical ® device are greatly influenced by the sleep-wake threshold applied. In the present study the Medium threshold produced the smallest bias for most parameters compared with PSG. Given the magnitude of measurement variability, confidence limits should be employed when interpreting changes in sleep parameters. Copyright © 2017 Sports Medicine Australia. All rights reserved.
Full Text Available Self-imposed short sleep durations are increasingly commonplace in society, and have considerable health and performance implications for individuals. Reduced sleep duration over multiple nights has similar behavioural effects to those observed following acute total sleep deprivation, suggesting that lack of sleep affects brain function cumulatively. A link between habitual sleep patterns and functional connectivity has previously been observed, and the effect of sleep duration on the brain's intrinsic functional architecture may provide a link between sleep status and cognition. However, it is currently not known whether differences in habitual sleep patterns across individuals are related to changes in the brain's white matter, which underlies structural connectivity. In the present study we use diffusion–weighted imaging and a group comparison application of tract based spatial statistics (TBSS to investigate changes to fractional anisotropy (FA and mean diffusivity (MD in relation to sleep duration and quality, hypothesising that white matter metrics would be positively associated with sleep duration and quality. Diffusion weighted imaging data was acquired from a final cohort of 33 (23–29 years, 10 female, mean 25.4 years participants. Sleep patterns were assessed for a 14 day period using wrist actigraphs and sleep diaries, and subjective sleep quality with the Pittsburgh Sleep Quality Index (PSQI. Median splits based on total sleep time and PSQI were used to create groups of shorter/longer and poorer/better sleepers, whose imaging data was compared using TBSS followed by post-hoc correlation analysis in regions identified as significantly different between the groups. There were significant positive correlations between sleep duration and FA in the left orbito-frontal region and the right superior corona radiata, and significant negative correlations between sleep duration and MD in right orbito-frontal white matter and the right
Mah, Cheri D; Mah, Kenneth E; Kezirian, Eric J; Dement, William C
To investigate the effects of sleep extension over multiple weeks on specific measures of athletic performance as well as reaction time, mood, and daytime sleepiness. Stanford Sleep Disorders Clinic and Research Laboratory and Maples Pavilion, Stanford University, Stanford, CA. Eleven healthy students on the Stanford University men's varsity basketball team (mean age 19.4 ± 1.4 years). Subjects maintained their habitual sleep-wake schedule for a 2-4 week baseline followed by a 5-7 week sleep extension period. Subjects obtained as much nocturnal sleep as possible during sleep extension with a minimum goal of 10 h in bed each night. Measures of athletic performance specific to basketball were recorded after every practice including a timed sprint and shooting accuracy. Reaction time, levels of daytime sleepiness, and mood were monitored via the Psychomotor Vigilance Task (PVT), Epworth Sleepiness Scale (ESS), and Profile of Mood States (POMS), respectively. Total objective nightly sleep time increased during sleep extension compared to baseline by 110.9 ± 79.7 min (P sleep extension (16.2 ± 0.61 sec at baseline vs. 15.5 ± 0.54 sec at end of sleep extension, P sleep extension (P sleep extension indicate that optimal sleep is likely beneficial in reaching peak athletic performance.
Loessl, B; Valerius, G; Kopasz, M; Hornyak, M; Riemann, D; Voderholzer, U
Adolescent sleep receives increasing attention. Several studies have shown that adolescents generally do not sleep enough. This survey assessed adolescents' sleep patterns, and results were compared with sleep logs. A total of 818 students aged 12-18 attending three different school types were asked to complete a questionnaire, adapted from the 'School Sleep Habits Survey', and filled in a sleep protocol over 2 weeks. Information on sleep patterns and demographic data were obtained additionally. A total of 601 students completed the questionnaire (i.e. 73.5% return rate), 55.1% female and 44.9% male. Average sleep duration during the week amounted to 8.04+/-0.89 h and 9.51+/-1.65 h on weekends. Sleep duration times on school days decreased from an average 8.64+/-0.83 h for the age category 12-13 years to 7.83+/-0.72 h for students above 16 years. 91.6% of all students slept less than 9.2 h per night during the week. Data from the 153 returned sleep logs showed even lower sleep times (7.75+/-0.82 h for school nights). The main hypothesis that students sleep on average considerably less than the recommended 9 h during weekdays was confirmed. Bedtimes changed throughout the week with the latest on Friday and Saturday nights and the least sleep around midweek. There were no significant group differences regarding school type and environment (rural vs. urban). Interestingly, the majority reported only little daytime sleepiness and no impaired performance. Results regarding the consequences of chronic sleep deprivation in the literature are inconclusive. The impact on physiological parameters, especially metabolic functions, requires further investigations.
Sarah M. Jay
Full Text Available Adequate sleep is fundamental to workplace performance. For volunteer firefighters who work in safety critical roles, poor performance at work can be life threatening. Extended shifts and sleeping conditions negatively impact sleep during multi-day fire suppression campaigns. Having sleep disordered breathing (SDB could contribute further to sleep deficits. Our aim was to investigate whether those with suspected SDB slept and performed more poorly during a fire ground simulation involving sleep restriction. Participants, n = 20 participated in a 3-day-4-night fire ground simulation. Based on oximetry desaturation index data collected during their participation, participants were retrospectively allocated to either a SDB (n = 8 or a non-SDB group (n = 12. The simulation began with an 8 h Baseline sleep (BL followed by two nights of restricted (4 h sleep and an 8 h recovery sleep (R. All sleeps were recorded using a standard electroencephalography (EEG montage as well as oxygen saturation. During the day, participants completed neurobehavioral (response time, lapses and subjective fatigue tasks. Mixed effects ANOVA were used to compare differences in sleep and wake variables. Analyses revealed a main effect of group for Total sleep (TST, REM , wake after sleep onset (WASO and Arousals/h with the SDB group obtaining less TST and REM and greater WASO and Arousals/h. The group × night interaction was significant for N3 with the SDB group obtaining 42 min less during BL. There was a significant main effect of day for RRT, lapses and subjective fatigue and a significant day × group interaction for RRT. Overall, the SDB group slept less, experienced more disturbed sleep and had poorer response time performance, which was exacerbated by the second night of sleep restriction. This could present a safety concern, particularly during longer campaigns and is worthy of further investigation. In addition, we would recommend promotion of awareness of SDB, its
Huang, Sha; Deshpande, Aadya; Yeo, Sing-Chen; Lo, June C; Chee, Michael W L; Gooley, Joshua J
The ability to recall facts is improved when learning takes place at spaced intervals, or when sleep follows shortly after learning. However, many students cram for exams and trade sleep for other activities. The aim of this study was to examine the interaction of study spacing and time in bed (TIB) for sleep on vocabulary learning in adolescents. In the Need for Sleep Study, which used a parallel-group design, 56 adolescents aged 15-19 years were randomly assigned to a week of either 5 h or 9 h of TIB for sleep each night as part of a 14-day protocol conducted at a boarding school. During the sleep manipulation period, participants studied 40 Graduate Record Examination (GRE)-type English words using digital flashcards. Word pairs were presented over 4 consecutive days (spaced items), or all at once during single study sessions (massed items), with total study time kept constant across conditions. Recall performance was examined 0 h, 24 h, and 120 h after all items were studied. For all retention intervals examined, recall of massed items was impaired by a greater amount in adolescents exposed to sleep restriction. In contrast, cued recall performance on spaced items was similar between sleep groups. Spaced learning conferred strong protection against the effects of sleep restriction on recall performance, whereas students who had insufficient sleep were more likely to forget items studied over short time intervals. These findings in adolescents demonstrate the importance of combining good study habits and good sleep habits to optimize learning outcomes. © 2016 Associated Professional Sleep Societies, LLC.
Full Text Available Circadian rhythms and restricted sleep length affect cognitive functions and, consequently, the performance of day to day activities. To date, no more than a few studies have explored the consequences of these factors on oculomotor behaviour. We have implemented a spatial cuing paradigm in an eye tracking experiment conducted four times of the day after one week of rested wakefulness and after one week of chronic partial sleep restriction. Our aim was to verify whether these conditions affect the number of a variety of saccadic task errors. Interestingly, we found that failures in response selection, i.e. premature responses and direction errors, were prone to time of day variations, whereas failures in response execution, i.e. omissions and commissions, were considerably affected by sleep deprivation. The former can be linked to the cue facilitation mechanism, while the latter to wake state instability and the diminished ability of top-down inhibition. Together, these results may be interpreted in terms of distinctive sensitivity of orienting and alerting systems to fatigue. Saccadic eye movements proved to be a novel and effective measure with which to study the susceptibility of attentional systems to time factors, thus, this approach is recommended for future research.
Full Text Available During adolescence, there is a tendency to sleep late andsleep less because of altered psychosocial and life-stylechanges. Recent studies have demonstrated the link betweensleeping less and gaining weight in children, adolescents, andadults. We studied the effect of late sleeping and sleepingless on body mass index (BMI in medical college freshmen.All participants were adolescents (104 male and 38 femaleadolescents, mean age 17.77±0.79 years. After obtaininginformed consent, they filled out a questionnaire about theirsleeping habits. Height and weight were measured after abrief history taking and clinical examination. BMI increasedsignificantly with decrease in total sleep duration and withdelayed bedtime. Late sleeping individuals (after midnighthad significantly less sleep duration (6.78 hours v 7.74 hours,P<0.001, more day time sleepiness (85.2% v 69.3%,P=0.033 and more gap between dinner time and going tosleep (234.16 min v 155.45 min, P<0.001. Increased BMI inlate sleepers may be explained by low physical activity duringthe day caused by excess sleepiness and increased calorieintake with a gap of 5-6 hours between dinner and sleep.Sleep habits of late sleeping and sleeping less contribute toincrease BMI in adolescents.
Lee, Shih-Yu; Wuertz, Caroline; Rogers, Rebecca; Chen, Yu-Ping
To describe the sleep characteristics and examine the associations among perceived stress, sleep disturbances, depressive symptoms, and physical symptoms among female college students. A total of 103 students completed a battery of questionnaires. The students experienced high stress during the school year. The majority of them slept less than 6 hours during weekdays and experienced moderate fatigue. High stress levels are associated with sleep disturbances, less nocturnal total sleep time, higher fatigue severity, and more depressive symptoms. Perceived stress and sleep disturbances are significant predictors for depressive symptoms and physical symptoms. Compared to the good sleepers, the poor sleepers reported more daytime sleepiness, depressive symptoms, and physical symptoms. Interventions to reduce stress and improve sleep are critically needed in college education.
Chung, Ka-Fai; Chan, Man-Sum; Lam, Ying-Yin; Lai, Cindy Sin-Yee; Yeung, Wing-Fai
Insufficient sleep among students is a major school health problem. School-based sleep education programs tailored to reach large number of students may be one of the solutions. A systematic review and meta-analysis was conducted to summarize the programs' effectiveness and current status. Electronic databases were searched up until May 2015. Randomized controlled trials of school-based sleep intervention among 10- to 19-year-old students with outcome on total sleep duration were included. Methodological quality of the studies was assessed using the Cochrane's risk of bias assessment. Seven studies were included, involving 1876 students receiving sleep education programs and 2483 attending classes-as-usual. Four weekly 50-minute sleep education classes were most commonly provided. Methodological quality was only moderate, with a high or an uncertain risk of bias in several domains. Compared to classes-as-usual, sleep education programs produced significantly longer weekday and weekend total sleep time and better mood among students at immediate post-treatment, but the improvements were not maintained at follow-up. Limited by the small number of studies and methodological limitations, the preliminary data showed that school-based sleep education programs produced short-term benefits. Future studies should explore integrating sleep education with delayed school start time or other more effective approaches. © 2017, American School Health Association.
Chambon, Stanislas; Galtier, Mathieu N; Arnal, Pierrick J; Wainrib, Gilles; Gramfort, Alexandre
Sleep stage classification constitutes an important preliminary exam in the diagnosis of sleep disorders. It is traditionally performed by a sleep expert who assigns to each 30 s of the signal of a sleep stage, based on the visual inspection of signals such as electroencephalograms (EEGs), electrooculograms (EOGs), electrocardiograms, and electromyograms (EMGs). We introduce here the first deep learning approach for sleep stage classification that learns end-to-end without computing spectrograms or extracting handcrafted features, that exploits all multivariate and multimodal polysomnography (PSG) signals (EEG, EMG, and EOG), and that can exploit the temporal context of each 30-s window of data. For each modality, the first layer learns linear spatial filters that exploit the array of sensors to increase the signal-to-noise ratio, and the last layer feeds the learnt representation to a softmax classifier. Our model is compared to alternative automatic approaches based on convolutional networks or decisions trees. Results obtained on 61 publicly available PSG records with up to 20 EEG channels demonstrate that our network architecture yields the state-of-the-art performance. Our study reveals a number of insights on the spatiotemporal distribution of the signal of interest: a good tradeoff for optimal classification performance measured with balanced accuracy is to use 6 EEG with 2 EOG (left and right) and 3 EMG chin channels. Also exploiting 1 min of data before and after each data segment offers the strongest improvement when a limited number of channels are available. As sleep experts, our system exploits the multivariate and multimodal nature of PSG signals in order to deliver the state-of-the-art classification performance with a small computational cost.
Swinbourne, Richard; Miller, Joanna; Smart, Daniel; Dulson, Deborah K; Gill, Nicholas
(1) Background: The purpose of the present study was to examine the efficacy of sleep extension in professional rugby players. The aims were to: (i) characterise sleep quantity in elite rugby players and determine changes in immune function and stress hormone secretion during a pre-season training programme; (ii) evaluate the efficacy of a sleep extension intervention in improving sleep, markers of physical stress, immune function and performance. (2) Methods: Twenty five highly trained athletes from a professional rugby team (age (mean ± SD) 25 ± 2.7 years; height 1.87 ± 0.07 m; weight 105 ± 12.1 kg) participated in a six week pre-post control-trial intervention study. Variables of sleep, immune function, sympathetic nervous activity, physiological stress and reaction times were measured. (3) Results: Sleep extension resulted in a moderate improvement in sleep quality scores ([mean; ± 90% confidence limits] −24.8%; ± 54.1%) and small to moderate increases in total sleep time (6.3%; ± 6.3%) and time in bed (7.3%; ± 3.6%). In addition, a small decrease in cortisol (−18.7%; ± 26.4%) and mean reaction times (−4.3%; ± 3.1%) was observed following the intervention, compared to the control. (4) Conclusions: Professional rugby players are at risk of poor sleep during pre-season training, with concomitant rises in physical stress. Implementing a sleep extension programme among professional athletes is recommended to improve sleep, with beneficial changes in stress hormone expression and reaction time performance.
Full Text Available (1 Background: The purpose of the present study was to examine the efficacy of sleep extension in professional rugby players. The aims were to: (i characterise sleep quantity in elite rugby players and determine changes in immune function and stress hormone secretion during a pre-season training programme; (ii evaluate the efficacy of a sleep extension intervention in improving sleep, markers of physical stress, immune function and performance. (2 Methods: Twenty five highly trained athletes from a professional rugby team (age (mean ± SD 25 ± 2.7 years; height 1.87 ± 0.07 m; weight 105 ± 12.1 kg participated in a six week pre-post control-trial intervention study. Variables of sleep, immune function, sympathetic nervous activity, physiological stress and reaction times were measured. (3 Results: Sleep extension resulted in a moderate improvement in sleep quality scores ([mean; ± 90% confidence limits] −24.8%; ± 54.1% and small to moderate increases in total sleep time (6.3%; ± 6.3% and time in bed (7.3%; ± 3.6%. In addition, a small decrease in cortisol (−18.7%; ± 26.4% and mean reaction times (−4.3%; ± 3.1% was observed following the intervention, compared to the control. (4 Conclusions: Professional rugby players are at risk of poor sleep during pre-season training, with concomitant rises in physical stress. Implementing a sleep extension programme among professional athletes is recommended to improve sleep, with beneficial changes in stress hormone expression and reaction time performance.
Ranjbaran, Ziba; Keefer, Laurie; Farhadi, Ashkan; Stepanski, Edward; Sedghi, Shahriar; Keshavarzian, Ali
Normal sleep is paramount for a healthy lifestyle and high quality of life. Sleep modulates the immune system and thus affects the course of several chronic inflammatory conditions. There are no reported studies that address the role of sleep disturbance in the course of inflammatory bowel disease (IBD). The aim of this study was to characterize sleep disturbance in IBD using validated measures of sleep and quality of life. A self-administered, mail-in questionnaire package was sent to 205 subjects after a brief instruction. The questionnaire package was composed of the Pittsburgh Sleep Quality Index (PSQI), a measure of disease severity and the IBD-Quality of Life Questionnaire. A total of 119 subjects were recruited (58% response rate): 80 with inactive IBD, 24 with irritable bowel syndrome (IBS) and 15 healthy controls. The IBD subjects reported significantly prolonged sleep latency, frequent sleep fragmentation, higher rate of using sleeping pills, decreased day-time energy, increased tiredness and poor overall sleep quality compared to healthy controls. The abnormal sleep patterns in IBD subjects were similar to IBS subjects. The reported sleep quality was correlated with IBD disease severity score (r(2) = 0.55, P = 0.02). Both IBD and IBS subjects thought that sleep and their disease status were correlated. The results show that IBD patients have significant sleep disturbance even when their disease is not active. This problem might affect quality of life, gastrointestinal symptoms and coping ability, and might potentially modify disease severity or increase risk of flare-up. Regardless of the primary or secondary origin of this problem, sleep disturbance should be addressed in the clinical management of patients with IBD.
Stringham, James M; Stringham, Nicole T; O'Brien, Kevin J
The dramatic rise in the use of smartphones, tablets, and laptop computers over the past decade has raised concerns about potentially deleterious health effects of increased "screen time" (ST) and associated short-wavelength (blue) light exposure. We determined baseline associations and effects of 6 months' supplementation with the macular carotenoids (MC) lutein, zeaxanthin, and mesozeaxanthin on the blue-absorbing macular pigment (MP) and measures of sleep quality, visual performance, and physical indicators of excessive ST. Forty-eight healthy young adults with at least 6 h of daily near-field ST exposure participated in this placebo-controlled trial. Visual performance measures included contrast sensitivity, critical flicker fusion, disability glare, and photostress recovery. Physical indicators of excessive screen time and sleep quality were assessed via questionnaire. MP optical density (MPOD) was assessed via heterochromatic flicker photometry. At baseline, MPOD was correlated significantly with all visual performance measures ( p eye strain, eye fatigue, and all visual performance measures, versus placebo ( p < 0.05 for all). Increased MPOD significantly improves visual performance and, in turn, improves several undesirable physical outcomes associated with excessive ST. The improvement in sleep quality was not directly related to increases in MPOD, and may be due to systemic reduction in oxidative stress and inflammation.
Van Ryswyk, Emer; Weeks, Richard; Bandick, Laura; O'Keefe, Michaela; Vakulin, Andrew; Catcheside, Peter; Barger, Laura; Potter, Andrew; Poulos, Nick; Wallace, Jarryd; Antic, Nick A
To improve well-being and performance indicators in a group of Australian Football League (AFL) players via a six-week sleep optimisation programme. Prospective intervention study following observations suggestive of reduced sleep and excessive daytime sleepiness in an AFL group. Athletes from the Adelaide Football Club were invited to participate if they had played AFL senior-level football for 1-5 years, or if they had excessive daytime sleepiness (Epworth Sleepiness Scale [ESS] >10), measured via ESS. An initial education session explained normal sleep needs, and how to achieve increased sleep duration and quality. Participants (n = 25) received ongoing feedback on their sleep, and a mid-programme education and feedback session. Sleep duration, quality and related outcomes were measured during week one and at the conclusion of the six-week intervention period using sleep diaries, actigraphy, ESS, Pittsburgh Sleep Quality Index, Profile of Mood States, Training Distress Scale, Perceived Stress Scale and the Psychomotor Vigilance Task. Sleep diaries demonstrated an increase in total sleep time of approximately 20 min (498.8 ± 53.8 to 518.7 ± 34.3; p sleep efficiency (p sleep efficiency, fatigue and vigour indicate that a sleep optimisation programme may improve athletes' well-being. More research is required into the effects of sleep optimisation on athletic performance.
Kalmbach, K.; Booth, V.; Behn, C. G. Diniz
The structure of human sleep changes across development as it consolidates from the polyphasic sleep of infants to the single nighttime sleep period typical in adults. Across this same developmental period, time scales of the homeostatic sleep drive, the physiological drive to sleep that increases with time spent awake, also change and presumably govern the transition from polyphasic to monophasic sleep behavior. Using a physiologically-based, sleep-wake regulatory network model for human sle...
Esbensen, A J; Hoffman, E K; Stansberry, E; Shaffer, R
There is a need for rigorous measures of sleep in children with Down syndrome as sleep is a substantial problem in this population and there are barriers to obtaining the gold standard polysomnography (PSG). PSG is cost-prohibitive when measuring treatment effects in some clinical trials, and children with Down syndrome may not cooperate with undergoing a PSG. Minimal information is available on the validity of alternative methods of assessing sleep in children with Down syndrome, such as actigraphy and parent ratings. Our study examined the concurrent and convergent validity of different measures of sleep, including PSG, actigraphy and parent reports of sleep among children with Down syndrome. A clinic (n = 27) and a community (n = 47) sample of children with Down syndrome were examined. In clinic, children with Down syndrome wore an actigraph watch during a routine PSG. In the community, children with Down syndrome wore an actigraph watch for a week at home at night as part of a larger study on sleep and behaviour. Their parent completed ratings of the child's sleep during that same week. Actigraph watches demonstrated convergent validity with PSG when measuring a child with Down syndrome's total amount of sleep time, total wake time after sleep onset and sleep period efficiency. In contrast, actigraph watches demonstrated poor correlations with parent reports of sleep, and with PSG when measuring the total time in bed and total wake episodes. Actigraphy, PSG and parent ratings of sleep demonstrated poor concurrent validity with clinical diagnosis of obstructive sleep apnoea. Our current data suggest that actigraph watches demonstrate convergent validity and are sensitive to measuring certain sleep constructs (duration, efficiency) in children with Down syndrome. However, parent reports, such as the Children's Sleep Habits Questionnaire, may be measuring other sleep constructs. These findings highlight the importance of selecting measures of sleep related to
Hung, Hsuan-Man; Chiang, Hsiao-Ching
Most women experience the worse sleep quality of their life during pregnancy and the early postpartum period. Although pregnancy typically accounts for a relatively short part of a woman's life, the related sleep disturbances may have a significant and negative impact on her long-term health. Approximately 78-80% of pregnant women experience sleep disturbances, including interruptions in deep sleep, decreased total sleep time, poor subjective sleep quality, frequent night waking, and reduced sleep efficacy. Sleep disturbances during pregnancy start during the first trimester and become prevalent during the third trimester. Related factors include physiological and psychosocial changes and an unhealthy lifestyle. As non-pharmacological interventions have the potential to improve sleep quality in 70% to 80% of patients with insomnia, this is the main approached that is currently used to treat pregnancy-related sleep disturbances. Examples of these non-pharmacological interventions include music therapy, aerobic exercise, massage, progressive muscle relaxation, multi-modal interventions, and the use of a maternity support belt. The efficacy and safety of other related non-pharmacological interventions such as auricular acupressure, cognitive therapy, tai chi, and aromatherapy remain uncertain, with more empirical research required. Additionally, non-pharmacological interventions do not effectively treat sleep disturbances in all pregnant women.
Patel, Salma I; Miller, Bernie W; Kosiorek, Heidi E; Parish, James M; Lyng, Philip J; Krahn, Lois E
To objectively assess whether a dog in the bedroom or bed disturbs sleep. From August 1, 2015, through December 31, 2015, we evaluated the sleep of humans and dogs occupying the same bedroom to determine whether this arrangement was conducive to sleep. The study included 40 healthy adults without sleep disorders and their dogs (no dogs dog a validated dog accelerometer for 7 nights. The mean ± SD age of the participants (88% women) was 44±14 years and body mass index was 25±6. The mean ± SD age of the dogs was 5±3 years and weight was 15±13 kg. Mean ± SD actigraphy data showed 475±101 minutes in bed, 404±99 minutes total sleep time, 81%±7% sleep efficiency, and 71±35 minutes wake time after sleep onset. The dogs' accelerometer activity during the corresponding human sleep period was characterized as mean ± SD minutes at rest, active, and at play of 413±102, 62±43, and 2±4. The dogs had mean ± SD 85%±15% sleep efficiency. Human sleep efficiency was lower if the dog was on the bed as opposed to simply in the room (P=.003). Humans with a single dog in their bedroom maintained good sleep efficiency; however, the dog's position on/off the bed made a difference. A dog's presence in the bedroom may not be disruptive to human sleep, as was previously suspected. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.
McCauley, Peter; Kalachev, Leonid V.; Mollicone, Daniel J.; Banks, Siobhan; Dinges, David F.; Van Dongen, Hans P. A.
Recent experimental observations and theoretical advances have indicated that the homeostatic equilibrium for sleep/wake regulation—and thereby sensitivity to neurobehavioral impairment from sleep loss—is modulated by prior sleep/wake history. This phenomenon was predicted by a biomathematical model developed to explain changes in neurobehavioral performance across days in laboratory studies of total sleep deprivation and sustained sleep restriction. The present paper focuses on the dynamics of neurobehavioral performance within days in this biomathematical model of fatigue. Without increasing the number of model parameters, the model was updated by incorporating time-dependence in the amplitude of the circadian modulation of performance. The updated model was calibrated using a large dataset from three laboratory experiments on psychomotor vigilance test (PVT) performance, under conditions of sleep loss and circadian misalignment; and validated using another large dataset from three different laboratory experiments. The time-dependence of circadian amplitude resulted in improved goodness-of-fit in night shift schedules, nap sleep scenarios, and recovery from prior sleep loss. The updated model predicts that the homeostatic equilibrium for sleep/wake regulation—and thus sensitivity to sleep loss—depends not only on the duration but also on the circadian timing of prior sleep. This novel theoretical insight has important implications for predicting operator alertness during work schedules involving circadian misalignment such as night shift work. Citation: McCauley P; Kalachev LV; Mollicone DJ; Banks S; Dinges DF; Van Dongen HPA. Dynamic circadian modulation in a biomathematical model for the effects of sleep and sleep loss on waking neurobehavioral performance. SLEEP 2013;36(12):1987-1997. PMID:24293775
Prince, Toni-Moi; Wimmer, Mathieu; Choi, Jennifer; Havekes, Robbert; Aton, Sara; Abel, Ted
Sleep deprivation disrupts hippocampal function and plasticity. In particular, long-term memory consolidation is impaired by sleep deprivation, suggesting that a specific critical period exists following learning during which sleep is necessary. To elucidate the impact of sleep deprivation on
BEERSMA, DGM; VANDENHOOFDAKKER, RH
Sleep and mood are clearly interrelated in major depression, as shown by the antidepressive effects of various experiments, such as total sleep deprivation, partial sleep deprivation, REM sleep deprivation, and temporal shifts of the sleep period. The prevailing hypotheses explaining these effects
Beersma, Domien G.M.; Hoofdakker, Rutger H. van den
Sleep and mood are clearly interrelated in major depression, as shown by the antidepressive effects of various experiments, such as total sleep deprivation, partial sleep deprivation, REM sleep deprivation, and temporal shifts of the sleep period. The prevailing hypotheses explaining these effects
Wang, Ji-Bo; Wang, Ming-Zheng; Ji, Ping
In this article, we consider a single machine scheduling problem with a time-dependent learning effect and deteriorating jobs. By the effects of time-dependent learning and deterioration, we mean that the job processing time is defined by a function of its starting time and total normal processing time of jobs in front of it in the sequence. The objective is to determine an optimal schedule so as to minimize the total completion time. This problem remains open for the case of -1 < a < 0, where a denotes the learning index; we show that an optimal schedule of the problem is V-shaped with respect to job normal processing times. Three heuristic algorithms utilising the V-shaped property are proposed, and computational experiments show that the last heuristic algorithm performs effectively and efficiently in obtaining near-optimal solutions.
Swanson, Leslie M; Arnedt, J Todd; Rosekind, Mark R; Belenky, Gregory; Balkin, Thomas J; Drake, Christopher
Chronic sleep deprivation is common among workers, and has been associated with negative work outcomes, including absenteeism and occupational accidents. The objective of the present study is to characterize reciprocal relationships between sleep and work. Specifically, we examined how sleep impacts work performance and how work affects sleep in individuals not at-risk for a sleep disorder; assessed work performance outcomes for individuals at-risk for sleep disorders, including insomnia, obstructive sleep apnea (OSA) and restless legs syndrome (RLS); and characterized work performance impairments in shift workers (SW) at-risk for shift work sleep disorders relative to SW and day workers. One-thousand Americans who work 30 h per week or more were asked questions about employment, work performance and sleep in the National Sleep Foundation's 2008 Sleep in America telephone poll. Long work hours were associated with shorter sleep times, and shorter sleep times were associated with more work impairments. Thirty-seven percent of respondents were classified as at-risk for any sleep disorder. These individuals had more negative work outcomes as compared with those not at-risk for a sleep disorder. Presenteeism was a significant problem for individuals with insomnia symptoms, OSA and RLS as compared with respondents not at-risk. These results suggest that long work hours may contribute to chronic sleep loss, which may in turn result in work impairment. Risk for sleep disorders substantially increases the likelihood of negative work outcomes, including occupational accidents, absenteeism and presenteeism. © 2010 European Sleep Research Society.
Le, Trung Q; Cheng, Changqing; Sangasoongsong, Akkarapol; Wongdhamma, Woranat; Bukkapatnam, Satish T S
Obstructive sleep apnea (OSA) is a common sleep disorder found in 24% of adult men and 9% of adult women. Although continuous positive airway pressure (CPAP) has emerged as a standard therapy for OSA, a majority of patients are not tolerant to this treatment, largely because of the uncomfortable nasal air delivery during their sleep. Recent advances in wireless communication and advanced ("bigdata") preditive analytics technologies offer radically new point-of-care treatment approaches for OSA episodes with unprecedented comfort and afforadability. We introduce a Dirichlet process-based mixture Gaussian process (DPMG) model to predict the onset of sleep apnea episodes based on analyzing complex cardiorespiratory signals gathered from a custom-designed wireless wearable multisensory suite. Extensive testing with signals from the multisensory suite as well as PhysioNet's OSA database suggests that the accuracy of offline OSA classification is 88%, and accuracy for predicting an OSA episode 1-min ahead is 83% and 3-min ahead is 77%. Such accurate prediction of an impending OSA episode can be used to adaptively adjust CPAP airflow (toward improving the patient's adherence) or the torso posture (e.g., minor chin adjustments to maintain steady levels of the airflow).
Noland, Heather; Price, James H; Dake, Joseph; Telljohann, Susan K
Sleep duration affects the health of children and adolescents. Shorter sleep durations have been associated with poorer academic performance, unintentional injuries, and obesity in adolescents. This study extends our understanding of how adolescents perceive and deal with their sleep issues. General education classes were randomly selected from a convenience sample of three high schools in the Midwest. Three hundred eighty-four ninth- to twelfth-grade students (57%) completed a self-administered valid and reliable questionnaire on sleep behaviors and perceptions of sleep. Most respondents (91.9%) obtained inadequate sleep (sleep each week night. The majority indicated that not getting enough sleep had the following effects on them: being more tired during the day (93.7%), having difficulty paying attention (83.6%), lower grades (60.8%), increase in stress (59.0%), and having difficulty getting along with others (57.7%). Some students reported engaging in harmful behaviors to help them sleep: taking sleeping pills (6.0%), smoking a cigarette to relax (5.7%), and drinking alcohol in the evening (2.9%). Students who received fewer hours of sleep were significantly more likely to report being stressed (p = .02) and were more likely to be overweight (p = .04). Inadequate sleep time may be contributing to adolescent health problems such as increased stress and obesity. Findings indicate a need for sleep hygiene education for adolescents and their parents. A long-term solution to chronic sleep deprivation among high school students could include delaying high school start times, such as was done successfully in the Minneapolis Public School District.
Asmussen, Søren; Fiorini, Pierre; Lipsky, Lester
the ready queue, or it may restart the task. The behavior of systems under the first two scenarios is well documented, but the third (RESTART) has resisted detailed analysis. In this paper we derive tight asymptotic relations between the distribution of task times without failures to the total time when...... including failures, for any failure distribution. In particular, we show that if the task time distribution has an unbounded support then the total time distribution H is always heavy-tailed. Asymptotic expressions are given for the tail of H in various scenarios. The key ingredients of the analysis...
Asmussen, Søren; Fiorini, Pierre; Lipsky, Lester
the ready queue, or it may restart the task. The behavior of systems under the first two scenarios is well documented, but the third (RESTART) has resisted detailed analysis. In this paper we derive tight asymptotic relations between the distribution of task times without failures and the total time when...... including failures, for any failure distribution. In particular, we show that if the task-time distribution has an unbounded support, then the total-time distribution H is always heavy tailed. Asymptotic expressions are given for the tail of H in various scenarios. The key ingredients of the analysis...
Arun, R; Pina, P; Rubin, D; Erichsen, D
Childhood obesity is a growing health challenge. Recent studies show that children with late bedtime and late awakening are more obese independent of total sleep time. In adolescents and adults, a delayed sleep phase has been associated with higher caloric intake. Furthermore, an adult study showed a positive correlation between REM sleep and energy balance. This relationship has not been demonstrated in children. However, it may be important as a delayed sleep phase would increase the proportion of REM sleep. This study investigated the relationship between hunger score and sleep physiology in a paediatric population. Thirty-six patients referred for a polysomnogram for suspected obstructive sleep apnoea were enrolled in the study. Sleep stages were recorded as part of the polysomnogram. Hunger scores were obtained using a visual analogue scale. Mean age was 9.6 ± 3.5 years. Mean hunger scores were 2.07 ± 2.78. Hunger scores were positively correlated with percentage of total rapid eye movement (REM) sleep (r = 0.438, P hunger score (r = -0.360, P hunger scores. These findings suggest that delayed bedtime, which increases the proportion of REM sleep and decreases the proportion of SWS, results in higher hunger levels in children. © 2015 World Obesity.
Baumeister, James; Dorrlan, Jillian; Banks, Siobhan; Chatburn, Alex; Smith, Ross T; Carskadon, Mary A; Lushington, Kurt; Thomas, Bruce H
Sleep deprivation is known to have serious deleterious effects on executive functioning and job performance. Augmented reality has an ability to place pertinent information at the fore, guiding visual focus and reducing instructional complexity. This paper presents a study to explore how spatial augmented reality instructions impact procedural task performance on sleep deprived users. The user study was conducted to examine performance on a procedural task at six time points over the course of a night of total sleep deprivation. Tasks were provided either by spatial augmented reality-based projections or on an adjacent monitor. The results indicate that participant errors significantly increased with the monitor condition when sleep deprived. The augmented reality condition exhibited a positive influence with participant errors and completion time having no significant increase when sleep deprived. The results of our study show that spatial augmented reality is an effective sleep deprivation countermeasure under laboratory conditions.
Varga, Andrew W; Kishi, Akifumi; Mantua, Janna; Lim, Jason; Koushyk, Viachaslau; Leibert, David P; Osorio, Ricardo S; Rapoport, David M; Ayappa, Indu
Hippocampal electrophysiology and behavioral evidence support a role for sleep in spatial navigational memory, but the role of particular sleep stages is less clear. Although rodent models suggest the importance of rapid eye movement (REM) sleep in spatial navigational memory, a similar role for REM sleep has never been examined in humans. We recruited subjects with severe obstructive sleep apnea (OSA) who were well treated and adherent with continuous positive airway pressure (CPAP). Restricting CPAP withdrawal to REM through real-time monitoring of the polysomnogram provides a novel way of addressing the role of REM sleep in spatial navigational memory with a physiologically relevant stimulus. Individuals spent two different nights in the laboratory, during which subjects performed timed trials before and after sleep on one of two unique 3D spatial mazes. One night of sleep was normally consolidated with use of therapeutic CPAP throughout, whereas on the other night, CPAP was reduced only in REM sleep, allowing REM OSA to recur. REM disruption via this method caused REM sleep reduction and significantly fragmented any remaining REM sleep without affecting total sleep time, sleep efficiency, or slow-wave sleep. We observed improvements in maze performance after a night of normal sleep that were significantly attenuated after a night of REM disruption without changes in psychomotor vigilance. Furthermore, the improvement in maze completion time significantly positively correlated with the mean REM run duration across both sleep conditions. In conclusion, we demonstrate a novel role for REM sleep in human memory formation and highlight a significant cognitive consequence of OSA. Copyright © 2014 the authors 0270-6474/14/3414571-07$15.00/0.
Full Text Available EEG sleep spindles are short (0.5-2.0 s bursts of activity in the 11-16 Hz band occurring during non-rapid eye movement (NREM sleep. This sporadic activity is thought to play a role in memory consolidation, brain plasticity, and protection of sleep integrity. Many automatic detectors have been proposed to assist or replace experts for sleep spindle scoring. However, these algorithms usually detect too many events making it difficult to achieve a good tradeoff between sensitivity (Se and false detection rate (FDr. In this work, we propose a semi-automatic detector comprising a sensitivity phase based on well-established criteria followed by a specificity phase using spatial and spectral criteria.In the sensitivity phase, selected events are those which amplitude in the 10 – 16 Hz band and spectral ratio characteristics both reject a null hypothesis (p <0.1 stating that the considered event is not a spindle. This null hypothesis is constructed from events occurring during rapid eye movement (REM sleep epochs. In the specificity phase, a hierarchical clustering of the selected candidates is done based on events’ frequency and spatial position along the anterior-posterior axis. Only events from the classes grouping most (at least 80% spindles scored by an expert are kept. We obtain Se = 93.2% and FDr = 93.0% in the first phase and Se = 85.4% and FDr = 86.2% in the second phase. For these two phases, Matthew’s correlation coefficients are respectively 0.228 and 0.324. Results suggest that spindles are defined by specific spatio-spectral properties and that automatic detection methods can be improved by considering these features.
Ramlee, Fatanah; Sanborn, Adam N; Tang, Nicole K Y
We conceptualized sleep quality judgment as a decision-making process and examined the relative importance of 17 parameters of sleep quality using a choice-based conjoint analysis. One hundred participants (50 good sleepers; 50 poor sleepers) were asked to choose between 2 written scenarios to answer 1 of 2 questions: "Which describes a better (or worse) night of sleep?". Each scenario described a self-reported experience of sleep, stringing together 17 possible determinants of sleep quality that occur at different times of the day (day before, pre-sleep, during sleep, upon waking, day after). Each participant answered 48 questions. Logistic regression models were fit to their choice data. Eleven of the 17 sleep quality parameters had a significant impact on the participants' choices. The top 3 determinants of sleep quality were: Total sleep time, feeling refreshed (upon waking), and mood (day after). Sleep quality judgments were most influenced by factors that occur during sleep, followed by feelings and activities upon waking and the day after. There was a significant interaction between wake after sleep onset and feeling refreshed (upon waking) and between feeling refreshed (upon waking) and question type (better or worse night of sleep). Type of sleeper (good vs poor sleepers) did not significantly influence the judgments. Sleep quality judgments appear to be determined by not only what happened during sleep, but also what happened after the sleep period. Interventions that improve mood and functioning during the day may inadvertently also improve people's self-reported evaluation of sleep quality. © Sleep Research Society 2017. Published by Oxford University Press [on behalf of the Sleep Research Society].
Giam, G C
This review discusses the need for sleep, effects of sleep deprivation on behaviour and performance in the military, and sleep management recommendations to optimise combat effectiveness. Most people, regardless of sex or race, prefer 7 to 8 hours of sleep each night. Sleeping during the day is less recuperative. Continuous sleep is more effective than multiple short naps-even when the total hours for naps is more. Ten to 20 minute naps are useful when continuous sleep is not possible. Sleep inertia is the 5 to 30 minute period of sluggishness after awakening and important military tasks should be avoided. Previously, continuous work episodes (CWEs) duration was restricted by limited night vision, unreliable equipment and reduced endurance of military personnel. With improved technology, CWEs are now restricted primarily by endurance which is affected by sleep deprivation. This was one of the experiences noted in recent conflicts (e.g. Desert Storm) by personnel in the air force, army and navy. Since there will be changes in operational requirements, several work-rest-sleep plans must be prepared. Sleeping the preferred 7 to 8 hours per 24 hours the week before an operation may help prepare for optimal performance. Personnel should be familiarised with conditions under which they may sleep. During combat, sleep management should ideally avoid situations where all personnel are exhausted at the same time. As sleep debt accumulates, a person's mood, motivation, attention, alertness, short-term memory, ability to complete routines, task performance (errors of omission more than errors of commission) and physical performance will become more negatively affected. Counter measures must then be taken (e.g. time for sleep or naps, changing routines or rotating jobs). Drugs like caffeine and amphetamine can help personnel stay awake. However, they may also keep them awake when they need to sleep- and on awakening, they could suffer from "hang-overs" and are less efficient
Barber, Larissa K; Cucalon, Maria S
University students often have sleep issues that arise from poor sleep hygiene practices and technology use patterns. Yet, technology-related behaviors are often neglected in sleep hygiene education. This study examined whether the Sleep Treatment Education Program for Students-modified to include information regarding managing technology use (STEPS-TECH)-helps improve both subjective and objective sleep outcomes among university students. Results of an experimental study among 78 university students showed improvements in objective indicators of sleep quantity (total sleep time) and sleep quality (less awakenings) during the subsequent week for students in the STEPS-TECH intervention group compared to a control group. Exploratory analyses indicated that effects were driven by improvements in weekend days immediately following the intervention. There were also no intervention effects on subjective sleep quality or quantity outcomes. In terms of self-reported behavioral responses to educational content in the intervention, there were no group differences in sleep hygiene practices or technology use before bedtime. However, the intervention group reported less technology use during sleep periods than the control group. These preliminary findings suggest that STEPS-TECH may be a useful educational tool to help improve objective sleep and reduce technology use during sleep periods among university students. Copyright © 2017 John Wiley & Sons, Ltd.
Bahammam, Ahmed S; Al-Khairy, Omar K; Al-Taweel, Ahmed A
This study was designed to assess sleep patterns among male medical students at different academic levels. Participants in this study were healthy male medical students in the first (L1), second (L2) and third (L3) academic levels of the College of Medicine, King Saud University, Riyadh, Saudi Arabia. The study was conducted during November 2001. A self-administered questionnaire was distributed to students to assess age, academic level, registered credit hours, sleep-wake schedule, naps, quality of sleep, total sleep time at night, possible factors affecting bedtime, and daytime sleepiness using the Epworth Sleepiness Scale (ESS). The final analysis included 129 students. Total sleep time at night + nap of the whole group was 5.9 +/- 1.6 hours. Twenty-nine students (22.4%) were defined to have excessive daytime sleepiness (EDS) based on ESS score of >10. Also, 83.3% of students reported napping during the daytime more than twice per week. Analysis of the sleep pattern of male medical students revealed that this group is sleep deprived, which in turn may affect their academic performance.
Burda , Michael C; Hamermesh , Daniel S; Weil , Philippe
Using time-diary data from 27 countries, we demonstrate a negative relationship between real GDP per capita and the female-male difference in total work time--the sum of work for pay and work at home. We also show that in rich non-Catholic countries on four continents men and women do the same amount of total work on average. Our survey results demonstrate that labor economists, macroeconomists, sociologists and the general public consistently believe that women perform more total work. The f...
Chennaoui, Mounir; Arnal, Pierrick J; Drogou, Catherine; Sauvet, Fabien; Gomez-Merino, Danielle
Sleep deprivation is known to suppress circulating trophic factors such as insulin-like growth factor (IGF)-I and brain-derived neurotrophic factor (BDNF). This experiment examined the effect of an intervention involving 6 nights of extended sleep before total sleep deprivation on this catabolic profile. In a randomized crossover design, 14 young men (age range: 26-37 years) were either in an extended (EXT; time in bed: 2100-0700 h) or habitual (HAB: 2230-0700 h) sleep condition, followed by 3 days in the laboratory with blood sampling at baseline (B), after 24 h of sleep deprivation (24h-SD), and after 1 night of recovery sleep (R). In the EXT condition compared with the HAB condition, free IGF-I levels were significantly higher at B, 24h-SD, and R (P sleep deprivation was for insulin levels, which were significantly higher after R compared with B. In a healthy adult, additional sleep over 1 week increased blood concentrations of the anabolic factor IGF-I before and during 24 h of sleep deprivation and after the subsequent recovery night without effects on BDNF. With further research, these findings may prove to be important in guiding effective lifestyle modifications to limit physical or cognitive deficits associated with IGF-I decrease with age.
Full Text Available Paraskevi Tsokanaki,1 Despina Moraitou,1 Georgia Papantoniou2 1Section of Cognitive and Experimental Psychology, School of Psychology, Aristotle University of Thessaloniki, Thessaloniki, 2Department of Early Childhood Education, University of Ioannina, Ioannina, Greece Abstract: It is well known that night sleep is a decisive factor for the effective functioning of the human body and mind. In addition to the role of sleep, older adults report that they are “morning types” and that their cognitive and emotional abilities seem to be at a higher level in the morning hours. In this vein, this study is aimed at examining the effect of sleep combined with the “time of day” condition on a specific ability that is crucial for interpersonal communication, namely, emotion recognition, in older adults. Specifically, the study compared older adults’ performance in decoding emotions from ecologically valid, dynamic visual cues, in two conditions: “early in the morning and after night sleep”, and “in the afternoon and after many hours since night sleep”. An emotion recognition task was administered twice to 37 community-dwelling older adults. The results showed a statistically significant higher performance in the morning in decoding all emotions presented, compared to the afternoon condition. Pleasant surprise, sadness, and anxiety were revealed as the most difficult emotions to be recognized in the afternoon condition. Keywords: aging, cognition, emotion recognition
Katsunuma, Ruri; Oba, Kentaro; Kitamura, Shingo; Motomura, Yuki; Terasawa, Yuri; Nakazaki, Kyoko; Hida, Akiko; Moriguchi, Yoshiya; Mishima, Kazuo
Epidemiological studies have shown that sleep debt increases the risk of obesity. Experimental total sleep deprivation (TSD) has been reported to activate the reward system in response to food stimuli, but food-related responses in everyday sleep habits, which could lead to obesity, have not been addressed. Here, we report that habitual sleep time at home among volunteers without any sleep concerns was shorter than their optimal sleep time estimated by the 9-day extended sleep intervention, which indicates that participants had already been in sleep debt in their usual sleep habits. The amygdala and anterior insula, which are responsible for both affective responses and reward prediction, were found to exhibit significantly lowered activity in the optimal sleep condition. Additionally, a subsequent one-night period of TSD reactivated the right anterior insula in response to food images; however, the activity level of amygdala remained lowered. These findings indicate that (1) our brain is at risk of hyperactivation to food triggers in everyday life, which could be a risk factor for obesity and lifestyle diseases, and (2) optimal sleep appears to reduce this hypersensitivity to food stimuli. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail firstname.lastname@example.org.
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Hugo F. Posada-Quintero
Full Text Available We analyzed multiple measures of the autonomic nervous system (ANS based on electrodermal activity (EDA and heart rate variability (HRV for young healthy subjects undergoing 24-h sleep deprivation. In this study, we have utilized the error awareness test (EAT every 2 h (13 runs total, to evaluate the deterioration of performance. EAT consists of trials where the subject is presented words representing colors. Subjects are instructed to press a button (“Go” trials or withhold the response if the word presented and the color of the word mismatch (“Stroop No-Go” trial, or the screen is repeated (“Repeat No-Go” trials. We measured subjects' (N = 10 reaction time to the “Go” trials, and accuracy to the “Stroop No-Go” and “Repeat No-Go” trials. Simultaneously, changes in EDA and HRV indices were evaluated. Furthermore, the relationship between reactiveness and vigilance measures and indices of sympathetic control based on HRV were analyzed. We found the performance improved to a stable level from 6 through 16 h of deprivation, with a subsequently sustained impairment after 18 h. Indices of higher frequencies of EDA related more to vigilance measures, whereas lower frequencies index (skin conductance leve, SCL measured the reactiveness of the subject. We conclude that indices of EDA, including those of the higher frequencies, termed TVSymp, EDASymp, and NSSCRs, provide information to better understand the effect of sleep deprivation on subjects' autonomic response and performance.
Full Text Available Morningness–eveningness is the preference for different times of day for activity and sleep. Here, we addressed the effects of sleep behavior and morningness–eveningness on sociosexuality. Three hundred students (M age = 22.75 years, with 95% between 18 and 28 participated online, answering questions about morningness–eveningness (rMEQ [Reduced Morningness–Eveningness Questionnaire], midpoint of sleep on free days (MSF, sleep duration, and the Sociosexuality Orientation Inventory–Revised (SOI-R. The SOI-R contains three subscales, Behavior, Attitude, and Desire. Evening orientation and short sleep duration were related to a higher total SOI-R and to the three subscales. Based on the linear models, the strongest effect on sociosexuality was produced by gender (27% explained variance while age accounted for 6% of variance. Nonadditive variance explained by sleep–wake behavior was 7% (MSF, 4% (sleep duration, and 4% (rMEQ scores; 3% rMEQ-based typology. Older age was related to less-restricted sociosexuality, and men were less restricted than women in Attitude and Desire. Sleep duration and rMEQ scores were associated with Attitude and Desire; but only MSF was significantly related to Behavior. The data show that sleep–wake variables are associated with sociosexuality, with evening orientation and shorter sleep duration being related to a less-restricted sociosexuality.
Chiu, Hsiao-Yean; Wang, Mei-Yeh; Chang, Cheng-Kuei; Chen, Ching-Min; Chou, Kuei-Ru; Tsai, Jen-Chen; Tsai, Pei-Shan
The relationship between a composite measure of insomnia and occupational or fatal accidents has been investigated previously; however, little is known regarding the effect of various insomnia symptoms on minor non-fatal accidents during work and leisure time. We investigated the predicting role of insomnia symptoms on minor non-fatal accidents during work and leisure time. Data from the 2005 Taiwan Social Development Trend Survey of 36,473 Taiwanese aged ≥18 years were analyzed in 2013. Insomnia symptoms, including difficulty in initiating sleep (DIS), difficulty in maintaining sleep (DMS), early morning awakening (EMA), and nonrestorative sleep (NRS) were investigated. A minor non-fatal accident was defined as any mishap such as forgetting to turn off the gas or faucets, accidental falls, and abrasions or cuts occurring during work and leisure time in the past month that do not require immediate medical attention. Multivariable logistic regression was performed to assess the odds ratios (ORs) and associated 95% confidence interval (CI) of minor non-fatal accidents (as a binary variable) for each insomnia symptom compared with those of people presenting no symptoms, while controlling for possible confounders. EMA and NRS increased the odds of minor non-fatal accidents occurring during work and leisure time (adjusted OR=1.19, 95% CI=1.08-1.32 and adjusted OR=1.27, 95% CI=1.17-1.37, respectively). EMA and NRS are two symptoms that are significantly associated with an increased likelihood of minor non-fatal accidents during work and leisure time after adjusting for of a range of covariates. Copyright © 2014 Elsevier Ltd. All rights reserved.
Depner, Christopher M; Melanson, Edward L; McHill, Andrew W; Wright, Kenneth P
Proteomics holds great promise for understanding human physiology, developing health biomarkers, and precision medicine. However, how much the plasma proteome varies with time of day and is regulated by the master circadian suprachiasmatic nucleus brain clock, assessed here by the melatonin rhythm, is largely unknown. Here, we assessed 24-h time-of-day patterns of human plasma proteins in six healthy men during daytime food intake and nighttime sleep in phase with the endogenous circadian clock (i.e., circadian alignment) versus daytime sleep and nighttime food intake out of phase with the endogenous circadian clock (i.e., circadian misalignment induced by simulated nightshift work). We identified 24-h time-of-day patterns in 573 of 1,129 proteins analyzed, with 30 proteins showing strong regulation by the circadian cycle. Relative to circadian alignment, the average abundance and/or 24-h time-of-day patterns of 127 proteins were altered during circadian misalignment. Altered proteins were associated with biological pathways involved in immune function, metabolism, and cancer. Of the 30 circadian-regulated proteins, the majority peaked between 1400 hours and 2100 hours, and these 30 proteins were associated with basic pathways involved in extracellular matrix organization, tyrosine kinase signaling, and signaling by receptor tyrosine-protein kinase erbB-2. Furthermore, circadian misalignment altered multiple proteins known to regulate glucose homeostasis and/or energy metabolism, with implications for altered metabolic physiology. Our findings demonstrate the circadian clock, the behavioral wake-sleep/food intake-fasting cycle, and interactions between these processes regulate 24-h time-of-day patterns of human plasma proteins and help identify mechanisms of circadian misalignment that may contribute to metabolic dysregulation.
Mohsen Khoshniat Nikoo
Full Text Available Background: Life style Changes during Ramadan month could possibly affect sleep-related behaviors such as total daily sleep time, sleep and wake up time and brain waves. In addition, Spirituality and religiosity have a marvelous influence on mental health and effective solutions against stress are being religious and believe in God. This review discusses the results of all related studies about possible effects of Ramadan fasting on various aspects of sleep pattern and mental health. Methods: Keywords such as ‘Ramadan’, ‘Ramadan Fasting’, ‘Islamic Fasting’, ‘Fasting in Ramadan’ and Fasting along Sleep, Chronotype, Sleep Latency, REM, NREM, Brain Wave, Psychology, Mental health, Religion, Mood, Depression, Social interaction, Depressive illness, Psychomotor performances, Bipolar disorders, Accident, Mania, Anxiety and Stress were searched via PubMed database, Scientific Information Datebas (SID and also some local journals, hence, 103 related articles from 1972 until 2010 were studied. Results: The results of studies about the effects of Ramadan fasting on sleep pattern is not similar and these differences could be due to cultural and life style discrepancy in several countries. Fasting during Ramadan could lead to delay in sleep-wake cycle, decrease in deep sleep and lack of awareness during the day. Conclusion: There are various reasons such as dietary pattern, hormonal changes and also stress which could alter the quantity and quality of sleep during Ramadan. Also, according to the available information, there is a relationship between fasting and mental health.
Bramley, Harry; Henson, Alyssa; Lewis, Mechelle M; Kong, Lan; Stetter, Christy; Silvis, Matthew
Sleep disturbance is a common problem following concussion. A retrospective chart review was conducted at a regional concussion clinic on patients 13 to 18 years of age between 2005 and 2011. Statistical analysis evaluated sleep disturbance and duration of concussion, as well as the use and effectiveness of melatonin. A total of 417 patients met inclusion criteria. One hundred twenty-three (34%) reported disturbance in sleep. There was no difference in sleep disturbance based on age, gender, or past number of concussions. Sleep disturbance was associated with a 3- to 4-fold increase in recovery time. Non-sport-related concussions were more likely to be associated with sleep disturbance compared to sport-related concussions (45% vs 29%, P = .01). Melatonin improved sleep disturbance in 67% of the patients. Evaluating sleep disorders following concussion is an important part of the assessment. These findings will help clinicians provide anticipatory guidance and treatment for adolescents recovering from concussion.
Garde, Anne Helene; Karlson, Bernt; Hansen, Åse Marie
The aim of the present chapter was to analyze whether measures of cortisol in saliva were associated with measures of sleep and to explore if divergent results were related to underlying differences in theoretic assumptions and methods. Measures of sleep quality included sleep duration, overall...... sleep quality, difficulty falling asleep, disturbed sleep, and sleep deprivation. Twenty-three papers were found to fulfill the inclusion criteria. Cortisol measures were grouped into single time points at different times during the day, deviations at different time periods during the day, reactivity...... and recovery after a standardized laboratory test, area under the curve and response to dexamethasone test. A large proportion of the studies included showed non-significant findings, which, in several cases, may be a result of low power. The most consistent results were a positive association between sleep...
Luciana Balester Mello de Godoy
Full Text Available To compare sleep quality and sustained attention of patients with Upper Airway Resistance Syndrome (UARS, mild Obstructive Sleep Apnea (OSA and normal individuals.UARS criteria were presence of excessive daytime sleepiness (Epworth Sleepiness Scale-ESS-≥ 10 and/or fatigue (Modified Fatigue Impact Scale-MFIS-≥ 38 associated to Apnea/hypopnea index (AHI ≤ 5 and Respiratory Disturbance Index (RDI > 5 events/hour of sleep or more than 30% of total sleep time with flow limitation. Mild OSA was considered if the presence of excessive daytime sleepiness (ESS ≥ 10 and/or fatigue (MFIS ≥ 38 associated to AHI ≥ 5 and ≤ 15 events/hour. "Control group" criteria were AHI < 5 events/hour and RDI ≤ 5 events/hour and ESS ≤ 9, without any sleep, clinical, neurological or psychiatric disorder. 115 individuals (34 UARS and 47 mild OSA patients and 34 individuals in "control group", adjusted for age, gender, body mass index (BMI and schooling years, performed sleep questionnaires and sustained attention evaluation. Psychomotor Vigilance Task (PVT was performed five times (each two hours from 8 a.m. to 4 p.m.UARS patients had worse sleep quality (Functional Outcomes of Sleep Questionnaire-FOSQ-and Pittsburgh Sleep Quality Index-PSQI: p < 0.05 and more fatigue than mild OSA patients (p = 0.003 and scored significantly higher in both Beck inventories than "control group" (p < 0.02. UARS patients had more lapses early in the morning (in time 1 compared to the results in the afternoon (time 5 than mild OSA (p = 0.02. Mild OSA patients had more lapses in times 2 than in time 5 compared to "control group" (p = 0.04.UARS patients have a worse sleep quality, more fatigue and a worse early morning sustained attention compared to mild OSA. These last had a worse sustained attention than controls.
Puffer, Ross C; Murphy, Meghan; Maloney, Patrick; Kor, Daryl; Nassr, Ahmad; Freedman, Brett; Fogelson, Jeremy; Bydon, Mohamad
A retrospective review of a consecutive series of spinal fusions comparing patient and procedural characteristics of patients who developed surgical site infections (SSIs) after spinal fusion. It is known that increased surgical time (incision to closure) is associated with a higher rate of postoperative SSIs. We sought to determine whether increased total anesthetic time (intubation to extubation) is a factor in the development of SSIs as well. In spine surgery for deformity and degenerative disease, SSI has been associated with operative time, revealing a nearly 10-fold increase in SSI rates in prolonged surgery. Surgical time is associated with infections in other surgical disciplines as well. No studies have reported whether total anesthetic time (intubation to extubation) has an association with SSIs. Surgical records were searched in a retrospective fashion to identify all spine fusion procedures performed between January 2010 and July 2012. All SSIs during that timeframe were recorded and compared with the list of cases performed between 2010 and 2012 in a case-control design. There were 20 (1.7%) SSIs in this fusion cohort. On univariate analyses of operative factors, there was a significant association between total anesthetic time (Infection 7.6 ± 0.5 hrs vs. no infection -6.0 ± 0.1 hrs, P operative time (infection 5.5 ± 0.4 hrs vs. no infection - 4.4 ± 0.06 hrs, P infections, whereas level of pathology and emergent surgery were not significant. On multivariate logistic analysis, BMI and total anesthetic time remained independent predictors of SSI whereas ASA status and operative time did not. Increasing BMI and total anesthetic time were independent predictors of SSIs in this cohort of over 1000 consecutive spinal fusions. 3.
Gerhart, James I; Burns, John W; Post, Kristina M; Smith, David A; Porter, Laura S; Burgess, Helen J; Schuster, Erik; Buvanendran, Asokumar; Fras, Anne Marie; Keefe, Francis J
Poor sleep quality among people with chronic low back pain appears to be related to worse pain, affect, poor physical function, and pain catastrophizing. The causal direction between poor sleep and pain remains an open question, however, as does whether sleep quality exerts effects on low back pain differently across the course of the day. This daily diary study examined lagged temporal associations between prior night sleep quality and subsequent day pain, affect, physical function and pain catastrophizing, the reverse lagged temporal associations between prior day pain-related factors and subsequent night sleep quality, and whether the time of day during which an assessment was made moderated these temporal associations. Chronic low back pain patients (n = 105) completed structured electronic diary assessments five times per day for 14 days. Items included patient ratings of their pain, affect, physical function, and pain catastrophizing. Collapsed across all observations, poorer sleep quality was significantly related to higher pain ratings, higher negative affect, lower positive affect, poorer physical function, and higher pain catastrophizing. Lagged analyses averaged across the day revealed that poorer prior night sleep quality significantly predicted greater next day patient ratings of pain, and poorer physical function and higher pain catastrophizing. Prior poorer night sleep quality significantly predicted greater reports of pain, and poorer physical function, and higher pain catastrophizing, especially during the early part of the day. Sleep quality × time of day interactions showed that poor sleepers reported high pain, and negative mood and low function uniformly across the day, whereas good sleepers reported relatively good mornings, but showed pain, affect and function levels comparable to poor sleepers by the end of the day. Analyses of the reverse causal pathway were mostly nonsignificant. Sleep quality appears related not only to pain intensity
Philipsen, Alexandra; Feige, Bernd; Al-Shajlawi, Anam; Schmahl, Christian; Bohus, Martin; Richter, Harald; Voderholzer, Ulrich; Lieb, Klaus; Riemann, Dieter
Previous studies have shown depression-like sleep abnormalities in borderline personality disorder (BPD). However, findings in BPD are not unequivocal for REM dysregulation, as well as for a decrement of slow wave sleep and sleep continuity disturbances. Earlier findings in sleep EEG abnormalities in BPD may have been confounded by concomitant depressive symptoms. Twenty unmedicated female BPD patients without current comorbid major depression and 20 sex- and age-matched control subjects entered the study. Conventional polysomnographic parameters and for the first time sleep EEG spectral power analysis was performed on two sleep laboratory nights. Subjective sleep parameters were collected by sleep questionnaires in order to assess the relationship between objective and subjective sleep measurements. BPD patients showed a tendency for shortened REM latency and significantly decreased NonREM sleep (stage 2). Spectral EEG analysis showed increased delta power in total NREM sleep as well as in REM sleep in BPD patients. Subjective ratings documented drastically impaired sleep quality in BPD patients for the two weeks before the study and during the two laboratory nights. Not-depressed BPD patients only showed tendencies for depression-like REM sleep abnormalities. Surprisingly, BPD patients displayed higher levels of delta power in the sleep EEG in NREM sleep than healthy control subjects. There was a marked discrepancy between objective and subjective sleep measurements, which indicates an altered perception of sleep in BPD. The underlying psychological and neurobiological mechanisms of these alterations are still unclear and need to be clarified in future studies including interventions on a pharmacological and cognitive-behavioral level.
Ko, Cheng-Hung; Fang, Ya-Wen; Tsai, Ling-Ling; Hsieh, Shulan
Experimental sleep fragmentation (SF) is characterized by frequent brief arousals without reduced total sleep time and causes daytime sleepiness and impaired neurocognitive processes. This study explored the impact of SF on error monitoring. Thirteen adults underwent auditory stimuli-induced high-level (H) and low-level (L) SF nights. Flanker task performance and electroencephalogram data were collected in the morning following SF nights. Compared to LSF, HSF induced more arousals and stage N1 sleep, decreased slow wave sleep and rapid-eye-movement sleep (REMS), decreased subjective sleep quality, increased daytime sleepiness, and decreased amplitudes of P300 and error-related positivity (Pe). SF effects on N1 sleep were negatively correlated with SF effects on the Pe amplitude. Furthermore, as REMS was reduced by SF, post-error accuracy compensations were greatly reduced. In conclusion, attentional processes and error monitoring were impaired following one night of frequent sleep disruptions, even when total sleep time was not reduced. Copyright © 2014 Elsevier B.V. All rights reserved.
R. Michelle Saré
Full Text Available In patients with fragile X syndrome (FXS, sleep problems are commonly observed but are not well characterized. In animal models of FXS (dfmr1 and Fmr1 knockout (KO/Fxr2 heterozygote circadian rhythmicity is affected, but sleep per se has not been examined. We used a home-cage monitoring system to assess total sleep time in both light and dark phases in Fmr1 KO mice at different developmental stages. Fmr1 KOs at P21 do not differ from controls, but genotype × phase interactions in both adult (P70 and P180 groups are statistically significant indicating that sleep in Fmr1 KOs is reduced selectively in the light phase compared to controls. Our results show the emergence of abnormal sleep in Fmr1 KOs during the later stages of brain maturation. Treatment of adult Fmr1 KO mice with a GABAB agonist, R-baclofen, did not restore sleep duration in the light phase. In adult (P70 Fmr1 KO/Fxr2 heterozygote animals, total sleep time was further reduced, once again in the light phase. Our data highlight the importance of the fragile X genes (Fmr1 and Fxr2 in sleep physiology and confirm the utility of these mouse models in enhancing our understanding of sleep disorders in FXS.
Keilani, Mohammad; Crevenna, Richard; Dorner, Thomas Ernst
Sleeping problems are very common in patients with chronic pain. The aim of the study was to investigate the association between different dimensions of chronic pain and sleep quality in chronic pain patients. In this cross-sectional interview-based questionnaire study, patients from 3 different pain treatment centers in Vienna aged 18-65 years, with pain lasting 3 months or longer were asked to participate. The association between the short-form McGill pain questionnaire (SF-MPQ) and sleep quality (sleep onset latency, interrupted sleep due to pain, sleep duration and recovering effect of sleep) was assessed. In this study 121 patients (male 32, female 89, mean age 49 ± 9 years) could be analyzed. Of the patients 38.8% needed more than 30 min for falling asleep, 63.6% reported sleep fragmentation, 30.6% slept less than 5 h and 60.3% reported no recovering effect of sleep. The strongest associations between pain characteristics and sleep quality were found for pain intensity and affective pain aspects. Logistic regression analyses revealed that one point more in the total score of SF-MPQ increased the odds of needing more than 30 min for falling asleep, waking up more than 3 times due to pain, sleeping less than 5 h, and perceiving the sleep as non-recovering, by 6%. Adjusting for physical and psychological quality of life lowered the odds ratios and the association was no longer significant. The results underline the importance of paying attention to sleep quality in patients with chronic pain. The results also indicate that psychological factors might mediate the association between pain and sleep quality.
Full Text Available Gian Gastone Mascetti Department of General Psychology, University of Padova, Padova, Italy Abstract: Sleep is a behavior characterized by a typical body posture, both eyes' closure, raised sensory threshold, distinctive electrographic signs, and a marked decrease of motor activity. In addition, sleep is a periodically necessary behavior and therefore, in the majority of animals, it involves the whole brain and body. However, certain marine mammals and species of birds show a different sleep behavior, in which one cerebral hemisphere sleeps while the other is awake. In dolphins, eared seals, and manatees, unihemispheric sleep allows them to have the benefits of sleep, breathing, thermoregulation, and vigilance. In birds, antipredation vigilance is the main function of unihemispheric sleep, but in domestic chicks, it is also associated with brain lateralization or dominance in the control of behavior. Compared to bihemispheric sleep, unihemispheric sleep would mean a reduction of the time spent sleeping and of the associated recovery processes. However, the behavior and health of aquatic mammals and birds does not seem at all impaired by the reduction of sleep. The neural mechanisms of unihemispheric sleep are unknown, but assuming that the neural structures involved in sleep in cetaceans, seals, and birds are similar to those of terrestrial mammals, it is suggested that they involve the interaction of structures of the hypothalamus, basal forebrain, and brain stem. The neural mechanisms promoting wakefulness dominate one side of the brain, while those promoting sleep predominates the other side. For cetaceans, unihemispheric sleep is the only way to sleep, while in seals and birds, unihemispheric sleep events are intermingled with bihemispheric and rapid eye movement sleep events. Electroencephalogram hemispheric asymmetries are also reported during bihemispheric sleep, at awakening, and at sleep onset, as well as being associated with a use
Krakow, Barry; Ulibarri, Victor A
Few studies have examined the co-morbidity between insomnia and sleep-disordered breathing in the clinical setting. This study evaluated treatment-seeking insomnia patients and their self-report of sleep breathing complaints. A retrospective chart review was conducted on 1,035 consecutive treatment-seeking, chronic insomnia patients who reported insomnia as their primary problem upon seeking care at a private, community-based sleep medical center. Measurements included the insomnia severity index, standard subjective sleep measures as well as rankings, attributions, and self-reports about sleep breathing disorders, problems, and symptoms. A total of 1,035 adult, treatment-seeking insomnia patients indicated insomnia interfered with daytime functioning, and their average insomnia severity was in the range of a clinically relevant problem: total sleep time (5.50 h, SD = 1.60), sleep efficiency (71.05 %, SD = 18.26), wake time after sleep onset (120.70 min, SD = 92.56), and an insomnia severity index (18.81, SD = 5.09). Of these 1,035 insomnia patients, 42 % also ranked a sleep breathing disorder among their list of reasons for seeking treatment, another 13 % revealed a concern about a sleep breathing problem, and another 26 % reported awareness of sleep breathing symptoms. Only 19 % of this clinical insomnia sample reported no awareness or concerns about sleep breathing disorders, problems, or symptoms. A greater proportion of men than women reported significantly more sleep breathing disorders, problems, or symptoms. Sleep breathing complaints were extremely common among a large sample of treatment-seeking, self-identified, adult chronic insomnia patients. Prospective prevalence research is needed to corroborate or revise these findings, and polysomnography should be considered in appropriate cohorts to determine the clinical relevance of treatment-seeking chronic insomnia patients' sleep breathing complaints.
Bolat, Mustafa Suat; Çınar, Önder; Akdeniz, Ekrem
We aimed to show the effect of retrograde JJ stenting and intraoperative antegrade JJ stenting techniques on operative time in patients who underwent laparoscopic pyeloplasty. A total of 34 patients were retrospectively investigated (15 male and 19 female) with ureteropelvic junction obstruction. Of the patients stentized under local anesthesia preoperatively, as a part of surgery, 15 were retrogradely stentized at the beginning of the procedure (Group 1), and 19 were antegradely stentized during the procedure (Group 2). A transperitoneal dismembered pyeloplasty technique was performed in all patients. The two groups were retrospectively compared in terms of complications, the mean total operative time, and the mean stenting times. The mean ages of the patients were 31.5±15.5 and 33.2±15.5 years (p=0.09), and the mean body mass indexes were 25.8±5.6 and 26.2.3±8.4 kg/m 2 in Group 1 and Group 2, respectively. The mean total operative times were 128.9±38.9 min and 112.7±21.9 min (p=0.04); the mean stenting times were 12.6±5.4 min and 3.5±2.4 min (p=0.02); and the mean rates of catheterization-to-total surgery times were 0.1 and 0.03 (p=0.01) in Group 1 and 2, respectively. The mean hospital stays and the mean anastomosis times were similar between the two groups (p>0.05). Antegrade JJ stenting during laparoscopic pyeloplasty significantly decreased the total operative time.
Hvolby, Allan; Jørgensen, Jan; Bilenberg, Niels
OBJECTIVE: Sleep problems have often been associated with attention deficit/hyperactivity disorder (ADHD). Parents of those with ADHD and children with ADHD report sleep difficulties more frequently than healthy children and their parents. The primary objective of this paper is to describe sleep...... regarding numbers of awakenings per night and total sleep time per night. Comorbid oppositional defiant disorder appeared not to have an added effect on problematic behaviour around bedtime. CONCLUSION: Parents of children with ADHD report that their children do not sleep properly more often than other...
Lira, Fabio Santos; Esteves, Andrea Maculano; Pimentel, Gustavo Duarte; Rosa, José Cesar; Frank, Miriam Kannebley; Mariano, Melise Oliveira; Budni, Josiane; Quevedo, João; Santos, Ronaldo Vagner Dos; de Mello, Marco Túlio
We sought explore the effects of doxorubicin on sleep patterns and locomotor activity. To investigate these effects, two groups were formed: a control group and a Doxorubicin (DOXO) group. Sixteen rats were randomly assigned to either the control or DOXO groups. The sleep patterns were examined by polysomnographic recording and locomotor activity was evaluated in an open-field test. In the light period, the total sleep time and slow wave sleep were decreased, while the wake after sleep onset and arousal were increased in the DOXO group compared with the control group (plocomotor activity.
Verrillo, Elisabetta; Bizzarri,