Neonatal Vitamin D Levels in Relation to Risk of Overweight at 7 Years in the Danish D-Tect Case-Cohort Study

DEFF Research Database (Denmark)

Jensen, Camilla B.; Lundqvist, Marika; Sørensen, Thorkild I. A.

2017-01-01

Background: Vitamin D level in pregnancy may be associated with risk of overweight in the offspring later in life. Methods: In a case-cohort study based on Danish biobanks and registers we examined the association between 25-hydroxy-vitamin D (25(OH)D) level at birth and overweight at 7 years....... Cases of overweight (n = 871) were randomly selected among 7-year-old children from the Copenhagen School Health Records Register (CSHRR) with a BMI above the 90th percentile. The cohort (n = 1,311) was a random sample selected among all Danish children born during the same period. Neonatal 25(OH...

Harmonising measures of knee and hip osteoarthritis in population-based cohort studies

DEFF Research Database (Denmark)

Leyland, K M; Gates, L S; Nevitt, M

2018-01-01

OBJECTIVE: Population-based osteoarthritis (OA) cohorts provide vital data on risk factors and outcomes of OA, however the methods to define OA vary between cohorts. We aimed to provide recommendations for combining knee and hip OA data in extant and future population cohort studies, in order to ...

Stratification for smoking in case-cohort studies of genetic polymorphisms and lung cancer

DEFF Research Database (Denmark)

Sørensen, Mette; López, Ana García; Andersen, Per Kragh

2009-01-01

and adjustment for smoking on the estimated effect of polymorphisms on lung cancer risk was explored in the case-cohort design. We used an empirical and a statistical simulation approach. The stratification strategies were: no smoking stratification, stratification for smoking status and stratification......The risk estimates obtained in studies of genetic polymorphisms and lung cancer differ markedly between studies, which might be due to chance or differences in study design, in particular the stratification/match of comparison group. The effect of different strategies for stratification...... for smoking duration. The study base was a prospective follow-up study with 57,053 participants. In the simulation approach the glutathione S-transferase T1 null polymorphism, as a model of any polymorphism, was added to simulated data in two different ways, assuming either absence or presence of association...

Mother and child characteristics at birth and early age leukemia: a case-cohort population-based study

Directory of Open Access Journals (Sweden)

Rejane de Souza Reis

2017-11-01

Full Text Available Objective: The population-based cancer registries (PBCR and the Information System on Live Births in Brazil (Sistema de Informações sobre Nascidos Vivos [SINASC] have information that enables the test for risk factors associated with leukemia at an early age. The aim of this study was to identify maternal and birth characteristics associated with early-age acute leukemia (EAL in Brazil. Methods: A case-cohort study was performed using secondary dataset information of PBCR and SINASC. The risk association variables were grouped into (i characteristics of the child at birth and (ii characteristics of maternal exposure during pregnancy. The case–control ratio was 1:4. Linkage was performed using R software; odds ratio (OR and 95% confidence interval (CI were calculated by logistic regression models. Results: EAL was associated with maternal occupational exposure to chemicals (agricultural, chemical, and petrochemical industry; adjOR: 2.18, 95% CI: 1.16–4.10 and with birth defects (adjOR: 3.62, 95% CI: 1.19–11.00. Conclusions: The results of this study, with the identification of EAL risk factors in population-based case-cohort study, strengthen the knowledge and improve databases, contributing to investigations on risk factors associated with childhood leukemia worldwide. Resumo: Objetivos: Os registros de câncer de base populacional (RCBP e o Sistema Nacional de Nascidos Vivos (SINASC possuem informações que possibilitam testar hipóteses sobre fatores de riscos associados às leucemias. O objetivo principal deste projeto é identificar quais as características ao nascimento das crianças que estariam associadas ao risco de desenvolver Leucemia Aguda (LA na primeira infância. Métodos: Foram utilizadas informações de 12 RCBP e do Sistema de Informação de Nascidos Vivos das mesmas localidades. Foram elegíveis 272 casos e 1.088 controles no período de 1996 a 2010. As associações de riscos de LA foram agrupadas em, (i caracter

SLE disease patterns in a Danish population-based lupus cohort: an 8-year prospective study

DEFF Research Database (Denmark)

Laustrup, H; Voss, A; Green, A

2009-01-01

In 1995 all systemic lupus erythematosus (SLE) patients in the county of Funen were retrieved from four separate and independent sources as part of an 8-year prospective study to determine the pattern of disease activity and damage accumulation in a community based lupus cohort of predominantly...... Scandinavian ancestry. Incident cases were subsequently identified by surveillance of these sources. Established and new cases underwent annual, structured interviews, clinical examination and blood sampling. The Systemic Lupus Erythematosus Diseases Activity Index SLEDAI and Systemic Lupus International...

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses.

Science.gov (United States)

Keogh, Ruth H; Mangtani, Punam; Rodrigues, Laura; Nguipdop Djomo, Patrick

2016-01-05

Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

Exposure to ambient air pollution and the incidence of dementia: A population-based cohort study.

Science.gov (United States)

Chen, Hong; Kwong, Jeffrey C; Copes, Ray; Hystad, Perry; van Donkelaar, Aaron; Tu, Karen; Brook, Jeffrey R; Goldberg, Mark S; Martin, Randall V; Murray, Brian J; Wilton, Andrew S; Kopp, Alexander; Burnett, Richard T

2017-11-01

Emerging studies have implicated air pollution in the neurodegenerative processes. Less is known about the influence of air pollution, especially at the relatively low levels, on developing dementia. We conducted a population-based cohort study in Ontario, Canada, where the concentrations of pollutants are among the lowest in the world, to assess whether air pollution exposure is associated with incident dementia. The study population comprised all Ontario residents who, on 1 April 2001, were 55-85years old, Canadian-born, and free of physician-diagnosed dementia (~2.1 million individuals). Follow-up extended until 2013. We used population-based health administrative databases with a validated algorithm to ascertain incident diagnosis of dementia as well as prevalent cases. Using satellite observations, land-use regression model, and an optimal interpolation method, we derived long-term average exposure to fine particulate matter (≤2.5μm in diameter) (PM 2.5 ), nitrogen dioxide (NO 2 ), and ozone (O 3 ), respectively at the subjects' historical residences based on a population-based registry. We used multilevel spatial random-effects Cox proportional hazards models, adjusting for individual and contextual factors, such as diabetes, brain injury, and neighborhood income. We conducted various sensitivity analyses, such as lagging exposure up to 10years and considering a negative control outcome for which no (or weaker) association with air pollution is expected. We identified 257,816 incident cases of dementia in 2001-2013. We found a positive association between PM 2.5 and dementia incidence, with a hazard ratio (HR) of 1.04 (95% confidence interval (CI): 1.03-1.05) for every interquartile-range increase in exposure to PM 2.5 . Similarly, NO 2 was associated with increased incidence of dementia (HR=1.10; 95% CI: 1.08-1.12). No association was found for O 3 . These associations were robust to all sensitivity analyses examined. These estimates translate to 6.1% of

Infective Endocarditis and Cancer Risk: A Population-Based Cohort Study.

Science.gov (United States)

Sun, Li-Min; Wu, Jung-Nan; Lin, Cheng-Li; Day, Jen-Der; Liang, Ji-An; Liou, Li-Ren; Kao, Chia-Hung

2016-03-01

This study investigated the possible relationship between endocarditis and overall and individual cancer risk among study participants in Taiwan.We used data from the National Health Insurance program of Taiwan to conduct a population-based, observational, and retrospective cohort study. The case group consisted of 14,534 patients who were diagnosed with endocarditis between January 1, 2000 and December 31, 2010. For the control group, 4 patients without endocarditis were frequency matched to each endocarditis patient according to age, sex, and index year. Competing risks regression analysis was conducted to determine the effect of endocarditis on cancer risk.A large difference was noted in Charlson comorbidity index between endocarditis and nonendocarditis patients. In patients with endocarditis, the risk for developing overall cancer was significant and 119% higher than in patients without endocarditis (adjusted subhazard ratio = 2.19, 95% confidence interval = 1.98-2.42). Regarding individual cancers, in addition to head and neck, uterus, female breast and hematological malignancies, the risks of developing colorectal cancer, and some digestive tract cancers were significantly higher. Additional analyses determined that the association of cancer with endocarditis is stronger within the 1st 5 years after endocarditis diagnosis.This population-based cohort study found that patients with endocarditis are at a higher risk for colorectal cancer and other cancers in Taiwan. The risk was even higher within the 1st 5 years after endocarditis diagnosis. It suggested that endocarditis is an early marker of colorectal cancer and other cancers. The underlying mechanisms must still be explored and may account for a shared risk factor of infection in both endocarditis and malignancy.

Early life risk factors for testicular cancer: a case-cohort study based on the Copenhagen School Health Records Register.

Science.gov (United States)

Piltoft, Johanne Spanggaard; Larsen, Signe Benzon; Dalton, Susanne Oksbjerg; Johansen, Christoffer; Baker, Jennifer L; Cederkvist, Luise; Andersen, Ingelise

2017-02-01

One established risk factors for testicular cancer is cryptorchidism. However, it remains unclear whether cryptorchidism is a risk factor in itself or whether the two conditions share common causes in early life (estrogen hypothesis), such as birth weight and birth order. The objective of this study is to utilize data from the Copenhagen School Health Records Register (CSHRR) to evaluate cryptorchidism, birth weight and birth order as risk factors for testicular cancer. The study population consisted of 408 cases of testicular cancer identified by a government issued identification number linkage of the entire CSHRR with the Danish Cancer Registry and a random subsample of 4819 males from the CSHRR. The study design was case-cohort and the period of follow-up between 2 April 1968 and 31 December 2003. Cryptorchidism was significantly associated with testicular cancer in crude analyses [hazard ratio (HR) = 3.60, 95% CI 2.79-4.65]. Birth weight was inversely associated with testicular cancer and no clear association with birth order was observed. The positive association between cryptorchidism and testicular cancer was only slightly attenuated controlling for birth weight and birth order and stratified on birth cohort (HR = 3.46, 95% CI 2.67-4.48). This study confirmed the robustness of the association between cryptorchidism and testicular cancer even after adjustment for birth weight and birth order. Furthermore, the study showed an inverse association between birth weight and testicular cancer.

Testing independence between two Poisson-generated multinomial variables in case-series and cohort studies.

Science.gov (United States)

Hocine, Mounia; Guillemot, Didier; Tubert-Bitter, Pascale; Moreau, Thierry

2005-12-30

In case-series or cohort studies, we propose a test of independence between the occurrences of two types of recurrent events (such as two repeated infections) related to an intermittent exposure (such as an antibiotic treatment). The test relies upon an extension of a recent method for analysing case-series data, in the presence of one type of recurrent event. The test statistic is derived from a bivariate Poisson generated-multinomial distribution. Simulations for checking the validity of the test concerning the type I error and the power properties are presented. The test is illustrated using data from a cohort on antibiotics bacterial resistance in schoolchildren. Copyright 2005 John Wiley & Sons, Ltd.

Update on the effect of exogenous hormone use on glioma risk in women: a meta-analysis of case-control and cohort studies.

Science.gov (United States)

Lan, Yu-Long; Wang, Xun; Lou, Jia-Cheng; Ma, Bin-Bin; Xing, Jin-Shan; Zou, Shuang; Zhang, Bo

2018-04-01

Various studies have confirmed the important roles of endogenous hormones in the development of gliomas, while the roles of exogenous hormones remain controversial. Based on case-control studies and cohort studies, a meta-analysis was exerted to explore the effect of two exogenous hormones use (HRT: hormone replacement therapy; OC: oral contraceptives) on glioma risk. 16 eligible studies, including 11 case-control studies and 5 cohort studies, containing 8055027 women, were included in our study. All included studies have reported the relative risks (RRs) or odds ratios (ORs), and 95% confidence intervals (CIs). We use the fixed-effects model to calculate the estimated overall risk. In case-control studies, the risk of glioma was lower in women who had ever been treated with an exogenous hormone than in the control group (HRT: OR 0.91, 95% CI 0.84-0.99; OC: OR 0.99, 95% CI 0.91-1.07). In research of cohort studies, similar results have been obtained (HRT: RR 0.95, 95% CI 0.83-1.08; OC: RR 0.75, 95% CI 0.66-0.84). Our study further confirmed that the use of exogenous hormones has an important impact on the risk of glioma in women. However, more prospective studies are needed to further confirm this conclusion.

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses

Directory of Open Access Journals (Sweden)

Ruth H. Keogh

2016-01-01

Full Text Available Abstract Background Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Methods Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. Results The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Conclusions Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

Maternal death audit in Rwanda 2009-2013: a nationwide facility-based retrospective cohort study.

Science.gov (United States)

Sayinzoga, Felix; Bijlmakers, Leon; van Dillen, Jeroen; Mivumbi, Victor; Ngabo, Fidèle; van der Velden, Koos

2016-01-22

Presenting the results of 5 years of implementing health facility-based maternal death audits in Rwanda, showing maternal death classification, identification of substandard (care) factors that have contributed to death, and conclusive recommendations for quality improvements in maternal and obstetric care. Nationwide facility-based retrospective cohort study. All cases of maternal death audited by district hospital-based audit teams between January 2009 and December 2013 were reviewed. Maternal deaths that were not subjected to a local audit are not part of the cohort. 987 audited cases of maternal death. Characteristics of deceased women, timing of onset of complications, place of death, parity, gravida, antenatal clinic attendance, reported cause of death, service factors and individual factors identified by committees as having contributed to death, and recommendations made by audit teams. 987 cases were audited, representing 93.1% of all maternal deaths reported through the national health management information system over the 5-year period. Almost 3 quarters of the deaths (71.6%) occurred at district hospitals. In 44.9% of these cases, death occurred in the post-partum period. Seventy per cent were due to direct causes, with post-partum haemorrhage as the leading cause (22.7%), followed by obstructed labour (12.3%). Indirect causes accounted for 25.7% of maternal deaths, with malaria as the leading cause (7.5%). Health system failures were identified as the main responsible factor for the majority of cases (61.0%); in 30.3% of the cases, the main factor was patient or community related. The facility-based maternal death audit approach has helped hospital teams to identify direct and indirect causes of death, and their contributing factors, and to make recommendations for actions that would reduce the risk of reoccurrence. Rwanda can complement maternal death audits with other strategies, in particular confidential enquiries and near-miss audits, so as to

Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study.

Science.gov (United States)

Lopez-del Burgo, Cristina; Gea, Alfredo; de Irala, Jokin; Martínez-González, Miguel A; Chavarro, Jorge E; Toledo, Estefania

2015-07-27

The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN) cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the cohort. Cases were women reporting difficulty getting pregnant. Controls did not consult due to difficulty conceiving and had at least one child during follow-up. After adjustment for potential confounders, we found no association between self-reported difficulty getting pregnant and the number of alcoholic beverages consumed per week, (Odds Ratio [OR] > 5 drinks/week vs. none = 1.04, 95% Confidence Interval [CI] = 0.72-1.51). No association between types of alcoholic beverage and difficulty conceiving (OR > 5 drinks of wine/week vs. none = 1.16, 95% CI = 0.72-1.88; OR > 5 drinks of beer/week vs. none = 1.06, 95% CI = 0.82-1.37; OR > 5 drinks of spirits/week vs. none = 1.24, 95% CI = 0.84-1.64) was observed. In conclusion, we found no association between alcohol intake and risk of consulting a physician due to difficulty conceiving. More studies are needed to clearly elucidate the effects of alcohol intake on women's fertility. In the meantime, recommendations about alcohol intake to couples trying to conceive have to be given cautiously.

Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study

Directory of Open Access Journals (Sweden)

Cristina Lopez-del Burgo

2015-07-01

Full Text Available The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the cohort. Cases were women reporting difficulty getting pregnant. Controls did not consult due to difficulty conceiving and had at least one child during follow-up. After adjustment for potential confounders, we found no association between self-reported difficulty getting pregnant and the number of alcoholic beverages consumed per week, (Odds Ratio [OR] > 5 drinks/week vs. none = 1.04, 95% Confidence Interval [CI] = 0.72–1.51. No association between types of alcoholic beverage and difficulty conceiving (OR > 5 drinks of wine/week vs. none = 1.16, 95% CI = 0.72–1.88; OR > 5 drinks of beer/week vs. none = 1.06, 95% CI = 0.82–1.37; OR > 5 drinks of spirits/week vs. none = 1.24, 95% CI = 0.84–1.64 was observed. In conclusion, we found no association between alcohol intake and risk of consulting a physician due to difficulty conceiving. More studies are needed to clearly elucidate the effects of alcohol intake on women’s fertility. In the meantime, recommendations about alcohol intake to couples trying to conceive have to be given cautiously.

Cancer in ANCA-Associated Glomerulonephritis: A Registry-Based Cohort Study

Directory of Open Access Journals (Sweden)

Sanjeevan Sriskandarajah

2017-01-01

Full Text Available Background. Immunosuppressive therapy for antineutrophil cytoplasmic antibody-associated vasculitis has been associated with increased malignancy risk. Objectives. To quantify the cancer risk associated with contemporary cyclophosphamide-sparing protocols. Methods. Patients from the Norwegian Kidney Biopsy Registry between 1988 and 2012 who had biopsy-verified pauci-immune glomerulonephritis and positive antineutrophil cytoplasmic antibody (ANCA serology were included. Standardised incidence ratios (SIRs were calculated to compare the study cohort with the general population. Results. The study cohort included 419 patients. During 3010 person-years, cancer developed in 41 patients (9.79%; the expected number of cancer cases was 37.5 (8.95%. The cohort had SIRs as follows: 1.09, all cancer types (95% CI, 0.81 to 1.49; 0.96, all types except nonmelanoma skin cancer (95% CI, 0.69 to 1.34; 3.40, nonmelanoma skin cancer (95% CI, 1.62 to 7.14; 3.52, hematologic cancer (95% CI, 1.32 to 9.37; 2.12, posttransplant cancer (95% CI, 1.01 to 4.44; and 1.53, during the 1–5-year follow-up after diagnosis (95% CI, 1.01 to 2.32. Conclusions. Cancer risk did not increase significantly in this cohort with ANCA-associated glomerulonephritis. However, increased risk of nonmelanoma skin cancer, posttransplant cancer, and hematologic cancer indicates an association between immunosuppression and malignancy.

A shared frailty model for case-cohort samples: parent and offspring relations in an adoption study

DEFF Research Database (Denmark)

Petersen, Liselotte; Sørensen, Thorkild I A; Andersen, Per Kragh

2010-01-01

of their biological and adoptive parents were collected with the purpose of studying the association of survival between the adoptee and his/her biological or adoptive parents. Motivated by this study, we explored how to make inference in a shared frailty model for case-cohort data. Our approach was to use inverse......The Danish adoption register contains data on the 12 301 Danish nonfamilial adoptions during 1924-1947. From that register a case-cohort sample was selected consisting of all case adoptees, that is those adoptees dying before age 70 years, and a random sample of 1683 adoptees. The survival data...... probability weighting to account for the sampling in a conditional, shared frailty Poisson model and to use the robust variance estimator proposed by Moger et al. (Statist. Med. 2008; 27:1062-1074).To explore the performance of the estimation procedure, a simulation study was conducted. We studied situations...

Chronic urinary tract infection and bladder carcinoma risk: a meta-analysis of case-control and cohort studies.

Science.gov (United States)

Akhtar, Saeed; Al-Shammari, Ahmad; Al-Abkal, Jarrah

2018-02-05

This meta-analysis of published case-control and cohort studies sought to quantify the magnitude and direction of association between chronic UTI (defined as the infection of the urinary tract that either does not respond to treatment or keeps recurring) and risk of bladder carcinoma (BCa) (i.e., including mainly urothelial carcinoma, squamous cell carcinoma or adenocarcinoma). A literature search was conducted using Medline, Embase, Ovid, Web of Science, Science Direct and Cochrane Library, which was supplemented with manual search of reference lists of the identified articles. Case-control and cohort studies examining UTI as a predictor of BCa risk published through June 2016 were eligible. Using random-effects models, odds ratios (OR) or relative risks (RR) from eligible studies were combined to synthesize summary effect estimates. The included studies were assessed for methodological quality and potential publication bias. Heterogeneity by study characteristics was examined by sub-group and meta-regression analyses. Eighteen case-control and three cohort studies published between 1963 and 2016 were eligible. Random-effects models showed that UTI was significantly associated with an increased BCa risk both in case-control studies (summary OR RE  = 2.33; 95% CI 1.86, 2.92) and cohort studies (summary RR RE  = 2.88; 95% CI 1.20, 6.89). The observed relationship of UTI with an increased BCa risk was independent of the study characteristics considered. No significant publication bias was detected. Chronic UTI was significantly and independently associated with an increased BCa risk. However, due to the presence of high between-study heterogeneity and inconsistent patterns of adjusted confounding effects, more data are needed to clarify the role of chronic UTI in causation of BCa and if established, prompt and effective treatment of UTI may minimize a substantial proportion of BCa risk.

Breast implants and anaplastic large-cell lymphoma: a danish population-based cohort study.

Science.gov (United States)

Vase, Maja Ølholm; Friis, Søren; Bautz, Andrea; Bendix, Knud; Sørensen, Henrik Toft; d'Amore, Francesco

2013-11-01

A potential link between breast implants and anaplastic large-cell lymphoma (ALCL) has been suggested. We examined lymphoma occurrence in a nationwide cohort of 19,885 Danish women who underwent breast implant surgery during 1973-2010. Standardized incidence ratios (SIR), with 95% confidence intervals (CI), for ALCL and lymphoma overall associated with breast implantation were calculated. During 179,246 person-years of follow-up, we observed 31 cases of lymphoma among cohort members. No cases of ALCL were identified. SIRs for ALCL and lymphoma overall were zero (95% CI, 0-10.3) and 1.20 (95% CI, 0.82-1.70), respectively. In our nationwide cohort study, we did not find an increased risk of lymphoma in general, or ALCL in particular, among Danish women who underwent breast implantation. However, our evaluation of ALCL risk was limited by the rarity of the disease. Our results do not support an association between breast implants and ALCL and are consistent with other studies on cancer risk and breast implants. ©2013 AACR.

Genetic variants in loci 1p13 and 9p21 and fatal coronary heart disease in a Norwegian case-cohort study.

Science.gov (United States)

Jansen, Mona Dverdal; Knudsen, Gun Peggy; Myhre, Ronny; Høiseth, Gudrun; Mørland, Jørg; Næss, Øyvind; Tambs, Kristian; Magnus, Per

2014-05-01

Single nucleotide polymorphisms (SNPs) in loci 1p13 and 9p21 have previously been found to be associated with incident coronary heart disease (CHD). This study aimed to investigate whether these SNPs show associations with fatal CHD in a population-based cohort study after adjustment for socioeconomic- and lifestyle-related CHD risk factors not commonly included in genetic association studies. Using the population-based Cohort of Norway (CONOR), a nested case-cohort study was set up and DNA from 2,953 subjects (829 cases and 2,124 non-cases) were genotyped. The association with fatal CHD was estimated for four SNPs, three from locus 1p13 and one from locus 9p21. Multivariable Cox regression was used to estimate unstratified and gender-stratified hazard ratios while adjusting for major CHD risk factors. The associations between three SNPs from locus 1p13 and non-HDL cholesterol levels were also estimated. Men homozygous for the risk alleles on rs1333049 (9p21) and rs14000 (1p13) were found to have significantly increased hazard ratios in crude and adjusted models, and the hazard ratios remained statistically significant when both genders were analyzed together. Adjustment for additional socioeconomic- and lifestyle-related CHD risk factors influenced the association estimates only slightly. No significant associations were observed between the other two SNPs in loci 1p13 (rs599839 and rs646776) and CHD mortality in either gender. Both rs599839 and rs646776 showed significant, gradual increases in non-HDL cholesterol levels with increasing number of risk alleles. This study confirms the association between 9p21 (rs1333049) and fatal CHD in a Norwegian population-based cohort. The effect was not influenced by several socioeconomic- and lifestyle-related risk factors. Our results show that 1p13 (rs14000) may also be associated with fatal CHD. SNPs at 1p13 (rs599839 and rs646776) were associated with non-HDL cholesterol levels.

The iPSYCH2012 case-cohort sample

DEFF Research Database (Denmark)

Pedersen, C B; Bybjerg-Grauholm, J; Pedersen, M G

2017-01-01

The Integrative Psychiatric Research (iPSYCH) consortium has established a large Danish population-based Case-Cohort sample (iPSYCH2012) aimed at unravelling the genetic and environmental architecture of severe mental disorders. The iPSYCH2012 sample is nested within the entire Danish population ...... and environmental aetiologies of severe mental disorders.Molecular Psychiatry advance online publication, 19 September 2017; doi:10.1038/mp.2017.196....

Development of pancreatic cancer is predictable well in advance using contrast-enhanced CT: a case-cohort study

Energy Technology Data Exchange (ETDEWEB)

Gonoi, Wataru; Hayashi, Takana Yamakawa; Okuma, Hidemi; Ohtomo, Kuni [The University of Tokyo, Department of Radiology, Graduate School of Medicine, Tokyo (Japan); Akahane, Masaaki [The University of Tokyo, Department of Radiology, Graduate School of Medicine, Tokyo (Japan); NTT Medical Centre Tokyo, Department of Radiology, Tokyo (Japan); Nakai, Yousuke; Mizuno, Suguru; Tateishi, Ryosuke; Isayama, Hiroyuki; Koike, Kazuhiko [The University of Tokyo, Department of Gastroenterology, Graduate School of Medicine, Tokyo (Japan)

2017-12-15

To investigate the radiological findings prognostic for the development of pancreatic adenocarcinoma in a cohort of patients with hepatocellular carcinoma, using multiphasic computed tomography (CT). A case-cohort study performed in a single university hospital. A database of patients who received hepatocellular carcinoma (HCC) treatment and trimonthly follow-up with four-phase dynamic CT was used (n = 1848). The cohort group was randomly extracted from the database (n = 103). The case group comprised nine patients from the database who developed pancreatic adenocarcinoma. The radiological findings were assessed during follow-up (average, 32 months). The incidence of pancreatic mass, inhomogeneous parenchyma, loss of fatty marbling and main pancreatic duct dilatation gradually increased from 4 to 13 months before the diagnosis of pancreatic adenocarcinoma. There was a significantly higher incidence of pancreatic mass, inhomogeneous parenchyma and loss of fatty marbling on CT at baseline (average, 34 months before diagnosis) in the case group compared with the cohort group (P values < 0.01) and those findings at baseline were revealed as prognostic factors for pancreatic carcinogenesis, respectively (log-rank test, P values < 0.001). Several radiological findings observed on multiphasic CT can assist in predicting pancreatic carcinogenesis well in advance. (orig.)

Biomarkers in differentiating clinical dengue cases: A prospective cohort study

Directory of Open Access Journals (Sweden)

Gary Kim Kuan Low

2015-12-01

Full Text Available Objective: To evaluate five biomarkers (neopterin, vascular endothelial growth factor-A, thrombomodulin, soluble vascular cell adhesion molecule 1 and pentraxin 3 in differentiating clinical dengue cases. Methods: A prospective cohort study was conducted whereby the blood samples were obtained at day of presentation and the final diagnosis were obtained at the end of patients’ follow-up. All patients included in the study were 15 years old or older, not pregnant, not infected by dengue previously and did not have cancer, autoimmune or haematological disorder. Median test was performed to compare the biomarker levels. A subgroup Mann-Whitney U test was analysed between severe dengue and non-severe dengue cases. Monte Carlo method was used to estimate the 2-tailed probability (P value for independent variables with unequal number of patients. Results: All biomarkers except thrombomodulin has P value < 0.001 in differentiating among the healthy subjects, non-dengue fever, dengue without warning signs and dengue with warning signs/severe dengue. Subgroup analysis for all the biomarkers between severe dengue and non-severe dengue cases was not statistically significant except vascular endothelial growth factor-A (P < 0.05. Conclusions: Certain biomarkers were able to differentiate the clinical dengue cases. This could be potentially useful in classifying and determining the severity of dengue infected patients in the hospital.

Nordic registry-based cohort studies: Possibilities and pitfalls when combining Nordic registry data.

Science.gov (United States)

Maret-Ouda, John; Tao, Wenjing; Wahlin, Karl; Lagergren, Jesper

2017-07-01

All five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) have nationwide registries with similar data structure and validity, as well as personal identity numbers enabling linkage between registries. These resources provide opportunities for medical research that is based on large registry-based cohort studies with long and complete follow-up. This review describes practical aspects, opportunities and challenges encountered when setting up all-Nordic registry-based cohort studies. Relevant articles describing registries often used for medical research in the Nordic countries were retrieved. Further, our experiences of conducting this type of study, including planning, acquiring permissions, data retrieval and data cleaning and handling, and the possibilities and challenges we have encountered are described. Combining data from the Nordic countries makes it possible to create large and powerful cohorts. The main challenges include obtaining all permissions within each country, usually in the local language, and retrieving the data. These challenges emphasise the importance of having experienced collaborators within each country. Following the acquisition of data, data management requires the understanding of the differences between the variables to be used in the various countries. A concern is the long time required between initiation and completion. Nationwide Nordic registries can be combined into cohorts with high validity and statistical power, but the considerable expertise, workload and time required to complete such cohorts should not be underestimated.

Use of fertility drugs and risk of ovarian cancer: Danish Population Based Cohort Study.

Science.gov (United States)

Jensen, Allan; Sharif, Heidi; Frederiksen, Kirsten; Kjaer, Susanne Krüger

2009-02-05

To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women. Population based cohort study. Danish hospitals and private fertility clinics. 54,362 women with infertility problems referred to all Danish fertility clinics during 1963-98. The median age at first evaluation of infertility was 30 years (range 16-55 years), and the median age at the end of follow-up was 47 (range 18-81) years. Included in the analysis were 156 women with invasive epithelial ovarian cancer (cases) and 1241 subcohort members identified in the cohort during follow-up in 2006. Effect of four groups of fertility drugs (gonadotrophins, clomifene citrate, human chorionic gonadotrophin, and gonadotrophin releasing hormone) on overall risk of ovarian cancer after adjustment for potential confounding factors. Analyses within cohort showed no overall increased risk of ovarian cancer after any use of gonadotrophins (rate ratio 0.83, 95% confidence interval 0.50 to 1.37), clomifene (1.14, 0.79 to 1.64), human chorionic gonadotrophin (0.89, 0.62 to 1.29), or gonadotrophin releasing hormone (0.80, 0.42 to 1.51). Furthermore, no associations were found between all four groups of fertility drugs and number of cycles of use, length of follow-up, or parity. No convincing association was found between use of fertility drugs and risk of ovarian cancer.

Predictors of Treatment Outcome for Retreatment Pulmonary Tuberculosis Cases among Tribal People of an Eastern India District: A Prospective Cohort Study

Directory of Open Access Journals (Sweden)

Rajib Saha

2016-01-01

Full Text Available Objective. The study was conducted to assess the treatment outcome of different category retreatment cases with the aim of finding out the important predictors of unfavorable outcomes. Methodology. This hospital based prospective cohort study was conducted in three tuberculosis units (TUs of west Midnapore (a district of Eastern India, covering mostly the tribal populated areas. Patients who were registered for Category II antituberculosis treatment between 1st quarter of 2013 (Jan to Mar and 4th quarter of 2013 (Oct to Dec were considered as our study cohort and they were followed up till December 2014. The study was started with 177 patients but ultimately ended with 165 patients. Results. Unfavorable outcome was observed among 24.8% patients. Among them mostly 51.2% were defaulter, 22% were failure case, and 26.8% died during treatment. Patients, who were minority by religion, were found 4 times more vulnerable for unfavorable outcome. Unfavorable outcome was found 7 times more common among retreatment TB cases who remain sputum positive after completion of initiation phase of Category II treatment. Conclusion. Programmatic approach should be specified to address the minority by religion population and to reduce the load of sputum positive cases after completion of initiation phase treatment by tracking them.

Plasma enterolactone and risk of colon and rectal cancer in a case-cohort study of Danish men and women

DEFF Research Database (Denmark)

Johnsen, Nina; Olsen, Anja; Thomsen, Birthe Lykke

2010-01-01

This case-cohort study examined the association between plasma enterolactone concentration and incidence of colon and rectal cancer in the Diet, Cancer and Health cohort, which enrolled 57,053 participants aged 50-64. Information about diet and lifestyle was obtained by questionnaire, and data on...

Identification and medical utilization of incident cases of alcohol dependence: A population-based case-control study.

Science.gov (United States)

Pan, Chun-Hung; Li, Min-Shan; Yang, Tien-Wey; Huang, Ming-Chyi; Su, Sheng-Shiang; Hung, Yen-Ni; Chen, Chiao-Chicy; Kuo, Chian-Jue

2018-05-05

Patients with alcohol dependence (AD) often seek help from medical professionals due to alcohol-related diseases, but the overall distribution of medical specialties identifying new AD cases is unclear. We investigated how such cases were identified and how medical resources were utilized before the identification of AD in a nationwide cohort. We enrolled a population-based cohort (N = 1,000,000) using the National Health Insurance Research Database of Taiwan; 8181 cases with incident AD were retrieved between January 1, 2000, and December 31, 2010. For this nested case-control study, four controls were matched for age and sex with each case based on risk-set sampling. We measured various dimensions of medical utilization before AD was diagnosed, including department visited, physical comorbidity, and medication used. Conditional logistic regression was used for estimating the variables associated with AD. Patients living in less urbanized areas who were unemployed were more likely to develop AD. The highest proportions (34.2%) of AD cases were identified in the internal medicine department, followed by the emergency (22.3%) and psychiatry (18.7%) departments. AD patients had a higher risk of comorbid chronic hepatic disease (adjusted RR = 2.72, p identification of AD than controls. AD patients also had greater numbers of hospital admissions than controls, including non-psychiatric and psychiatric hospitalizations. Outpatient visit numbers were similar for AD patients and controls. The findings indicate that clinicians providing care in diverse medical settings should be prepared to screen for unhealthy alcohol use and to mitigate its detrimental effects. Copyright © 2018 Elsevier B.V. All rights reserved.

"EMMA Study: a Brazilian community-based cohort study of stroke mortality and morbidity"

Directory of Open Access Journals (Sweden)

Alessandra Carvalho Goulart

Full Text Available ABSTRACT CONTEXT AND OBJECTIVE: Stroke has a high burden of disability and mortality. The aim here was to evaluate epidemiology, risk factors and prognosis for stroke in the EMMA Study (Study of Stroke Mortality and Morbidity. DESIGN AND SETTINGS: Prospective community-based cohort carried out in Hospital Universitário, University of São Paulo, 2006-2014. METHODS: Stroke data based on fatal and non-fatal events were assessed, including sociodemographic data, mortality and predictors, which were evaluated by means of logistic regression and survival analyses. RESULTS: Stroke subtype was better defined in the hospital setting than in the local community. In the hospital phase, around 70% were first events and the ischemic subtype. Among cerebrovascular risk factors, the frequency of alcohol intake was higher in hemorrhagic stroke (HS than in ischemic stroke (IS cases (35.4% versus 12.3%, P < 0.001. Low education was associated with higher risk of death, particularly after six months among IS cases (odds ratio, OR, 4.31; 95% confidence interval, CI, 1.34-13.91. The risk of death due to hemorrhagic stroke was greater than for ischemic stroke and reached its maximum 10 days after the event (OR: 3.31; 95% CI: 1.55-7.05. Four-year survival analysis on 665 cases of first stroke (82.6% ischemic and 17.4% hemorrhagic showed an overall survival rate of 48%. At four years, the highest risks of death were in relation to ischemic stroke and illiteracy (hazard ratio, HR: 1.83; 95% CI: 1.26-2.68 and diabetes (HR: 1.45; 95% CI: 1.07-1.97. Major depression presented worse one-year survival (HR: 4.60; 95% CI: 1.36-15.55. CONCLUSION: Over the long term, the EMMA database will provide additional information for planning resources destined for the public healthcare system.

Sleep disorders increase the risk of burning mouth syndrome: a retrospective population-based cohort study.

Science.gov (United States)

Lee, Chun-Feng; Lin, Kuan-Yu; Lin, Ming-Chia; Lin, Cheng-Li; Chang, Shih-Ni; Kao, Chia-Hung

2014-11-01

Sleep disorders (SD), including apnea and nonapnea, and burning mouth syndrome (BMS) have been mutually associated with systemic diseases. Based on our research, the association between BMS and SD has not been elucidated. We determined whether SD patients have an increased risk of BMS. We used information from health insurance claims obtained from the Taiwanese National Health Insurance (NHI) program. We identified patients newly diagnosed with sleep apnea syndrome between 1998 and 2001 as the apnea SD cohort, and newly diagnosed patients with nonapnea SD as the nonapnea SD cohort. The non-SD cohort was 1:2 frequency matched the case group according to sex, age, and index year. We analyzed the risks of BMS by using Cox proportional hazards regression models. Compared with the non-SD cohort, both of the apnea SD (adjusted HR = 2.56, 95% CI = 1.30-5.05) and nonapnea SD (adjusted HR = 2.89, 95% CI = 2.51-3.34) were associated with a significantly higher risk of BMS. The hazard ratio (HR) increased with increased age in the apnea SD cohort and in the nonapnea SD cohort compared with patients younger than 40 years of age. Female apnea SD patients (IRR = 4.63, 95% CI = 3.82-5.61) had a higher risk of developing BMS than did male patients (IRR = 1.76, 95% CI = 1.39-2.24). Based on our research, SD might increase the risk of BMS. Copyright © 2014 Elsevier B.V. All rights reserved.

"EMMA Study: a Brazilian community-based cohort study of stroke mortality and morbidity".

Science.gov (United States)

Goulart, Alessandra Carvalho

2016-01-01

Stroke has a high burden of disability and mortality. The aim here was to evaluate epidemiology, risk factors and prognosis for stroke in the EMMA Study (Study of Stroke Mortality and Morbidity). Prospective community-based cohort carried out in Hospital Universitário, University of São Paulo, 2006-2014. Stroke data based on fatal and non-fatal events were assessed, including sociodemographic data, mortality and predictors, which were evaluated by means of logistic regression and survival analyses. Stroke subtype was better defined in the hospital setting than in the local community. In the hospital phase, around 70% were first events and the ischemic subtype. Among cerebrovascular risk factors, the frequency of alcohol intake was higher in hemorrhagic stroke (HS) than in ischemic stroke (IS) cases (35.4% versus 12.3%, P hemorrhagic stroke was greater than for ischemic stroke and reached its maximum 10 days after the event (OR: 3.31; 95% CI: 1.55-7.05). Four-year survival analysis on 665 cases of first stroke (82.6% ischemic and 17.4% hemorrhagic) showed an overall survival rate of 48%. At four years, the highest risks of death were in relation to ischemic stroke and illiteracy (hazard ratio, HR: 1.83; 95% CI: 1.26-2.68) and diabetes (HR: 1.45; 95% CI: 1.07-1.97). Major depression presented worse one-year survival (HR: 4.60; 95% CI: 1.36-15.55). Over the long term, the EMMA database will provide additional information for planning resources destined for the public healthcare system.

The incidence and prevalence of pterygium in South Korea: A 10-year population-based Korean cohort study.

Directory of Open Access Journals (Sweden)

Tyler Hyungtaek Rim

Full Text Available Although numerous population-based studies have reported the prevalences and risk factors for pterygium, information regarding the incidence of pterygium is scarce. This population-based cohort study aimed to evaluate the South Korean incidence and prevalence of pterygium. We retrospectively obtained data from a nationally representative sample of 1,116,364 South Koreans in the Korea National Health Insurance Service National Sample Cohort (NHIS-NSC. The associated sociodemographic factors were evaluated using multivariable Cox regression analysis, and the hazard ratios and confidence intervals were calculated. Pterygium was defined based on the Korean Classification of Diseases code, and surgically removed pterygium was defined as cases that required surgical removal. We identified 21,465 pterygium cases and 8,338 surgically removed pterygium cases during the study period. The overall incidences were 2.1 per 1,000 person-years for pterygium and 0.8 per 1,000 person-years for surgically removed pterygium. Among subjects who were ≥40 years old, the incidences were 4.3 per 1,000 person-years for pterygium and 1.7 per 1,000 person-years for surgically removed pterygium. The overall prevalences were 1.9% for pterygium and 0.6% for surgically removed pterygium, and the prevalences increased to 3.8% for pterygium and 1.4% for surgically removed pterygium among subjects who were ≥40 years old. The incidences of pterygium decreased according to year. The incidence and prevalence of pterygium were highest among 60-79-year-old individuals. Increasing age, female sex, and living in a relatively rural area were associated with increased risks of pterygium and surgically removed pterygium in the multivariable Cox regression analysis. Our analyses of South Korean national insurance claims data revealed a decreasing trend in the incidence of pterygium during the study period.

Alzheimer's Disease Sequencing Project discovery and replication criteria for cases and controls: Data from a community-based prospective cohort study with autopsy follow-up.

Science.gov (United States)

Crane, Paul K; Foroud, Tatiana; Montine, Thomas J; Larson, Eric B

2017-12-01

The Alzheimer's Disease Sequencing Project (ADSP) used different criteria for assigning case and control status from the discovery and replication phases of the project. We considered data from a community-based prospective cohort study with autopsy follow-up where participants could be categorized as case, control, or neither by both definitions and compared the two sets of criteria. We used data from the Adult Changes in Thought (ACT) study including Diagnostic and Statistical Manual-IV criteria for dementia status, McKhann et al. criteria for clinical Alzheimer's disease, and Braak and Consortium to Establish a Registry for AD findings on neurofibrillary tangles and neuritic plaques to categorize the 621 ACT participants of European ancestry who died and came to autopsy. We applied ADSP discovery and replication definitions to identify controls, cases, and people who were neither controls nor cases. There was some agreement between the discovery and replication definitions. Major areas of discrepancy included the finding that only 40% of the discovery sample controls had sufficiently low levels of neurofibrillary tangles and neuritic plaques to be considered controls by the replication criteria and the finding that 16% of the replication phase cases were diagnosed with non-AD dementia during life and thus were excluded as cases for the discovery phase. These findings should inform interpretation of genetic association findings from the ADSP. Differences in genetic association findings between the two phases of the study may reflect these different phenotype definitions from the discovery and replication phase of the ADSP. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Tourette syndrome increases risk of bone fractures: a population-based cohort study.

Science.gov (United States)

Lu, Yuan-Yuan; Wang, Ming-Yu; Wei, I-Hua; Lin, Che-Chen; Huang, Chih-Chia

2017-05-01

This study assesses the risk of fractures among children with Tourette syndrome (TS), and identifies the effects of comorbidities and antipsychotics. We randomly sampled the claims data of 1 million enrollees in the National Health Insurance program of Taiwan, and identified 1258 children with TS diagnosed between 2000 and 2010. Additionally, 12,580 children without TS who were frequency matched for sex, age, residential area, parental occupation, and index year were identified for comparison. The children's cases were followed until December 31, 2010, or censored to ascertain incident fractures cases and associations with comorbidities of attention-deficit/hyperactivity disorder (ADHD) or obsessive-compulsive disorder (OCD) and treatments with antipsychotics, antidepressants, or clonidine. The TS cohort had a 1.27-fold higher incidence of fractures than did the comparison cohort (190.37 vs. 149.94 per 10,000 person-years), with an adjusted hazard ratio (HR) of 1.28 [95% confidence interval (CI) 1.06-1.55] based on multivariable Cox regression analysis. This increased risk of fractures was apparent for fractures of the skull, neck, and spine. Comorbid ADHD and OCD did not result in an additional risk of fractures. The children without both ADHD and OCD were also at a higher risk of fractures, indicating that TS alone increases the risk of fractures. The children taking antipsychotics had a reduced risk of fractures, and the adjusted HR decreased to 1.17 (95% CI 0.90-1.52). Children with TS have an increased risk of fractures. ADHD and OCD do not increase the risk further.

Single Nucleotide Polymorphisms in IL1B and the Risk of Acute Coronary Syndrome: A Danish Case-Cohort Study

DEFF Research Database (Denmark)

Stegger, Jakob Gerhard; Schmidt, Erik Berg; Tjonneland, Anne

2012-01-01

Background: Interleukin-1B (IL-1B) is a key pro-inflammatory cytokine that has been associated with the development of atherosclerosis and myocardial infarction. However, the prospective associations between functional single nucleotide polymorphisms (SNPs) in IL1B and incident acute coronary...... and 234 women). All cases were validated by review of medical records, and information on covariates was collected by study technicians. The study was conducted according to a case-cohort study design including ACS cases and a sex-stratified sub cohort of 1663 participants drawn randomly from the entire...... IL1B haplotypes and risk factors, respectively. Conclusions/Significance: Genetic variation in the promoter region of IL1B may not be associated with incident ACS in men or women above the age of 50 years....

Effectiveness of one dose of oral cholera vaccine in response to an outbreak: a case-cohort study.

Science.gov (United States)

Azman, Andrew S; Parker, Lucy A; Rumunu, John; Tadesse, Fisseha; Grandesso, Francesco; Deng, Lul L; Lino, Richard Laku; Bior, Bior K; Lasuba, Michael; Page, Anne-Laure; Ontweka, Lameck; Llosa, Augusto E; Cohuet, Sandra; Pezzoli, Lorenzo; Sodjinou, Dossou Vincent; Abubakar, Abdinasir; Debes, Amanda K; Mpairwe, Allan M; Wamala, Joseph F; Jamet, Christine; Lessler, Justin; Sack, David A; Quilici, Marie-Laure; Ciglenecki, Iza; Luquero, Francisco J

2016-11-01

Oral cholera vaccines represent a new effective tool to fight cholera and are licensed as two-dose regimens with 2-4 weeks between doses. Evidence from previous studies suggests that a single dose of oral cholera vaccine might provide substantial direct protection against cholera. During a cholera outbreak in May, 2015, in Juba, South Sudan, the Ministry of Health, Médecins Sans Frontières, and partners engaged in the first field deployment of a single dose of oral cholera vaccine to enhance the outbreak response. We did a vaccine effectiveness study in conjunction with this large public health intervention. We did a case-cohort study, combining information on the vaccination status and disease outcomes from a random cohort recruited from throughout the city of Juba with that from all the cases detected. Eligible cases were those aged 1 year or older on the first day of the vaccination campaign who sought care for diarrhoea at all three cholera treatment centres and seven rehydration posts throughout Juba. Confirmed cases were suspected cases who tested positive to PCR for Vibrio cholerae O1. We estimated the short-term protection (direct and indirect) conferred by one dose of cholera vaccine (Shanchol, Shantha Biotechnics, Hyderabad, India). Between Aug 9, 2015, and Sept 29, 2015, we enrolled 87 individuals with suspected cholera, and an 898-person cohort from throughout Juba. Of the 87 individuals with suspected cholera, 34 were classified as cholera positive, 52 as cholera negative, and one had indeterminate results. Of the 858 cohort members who completed a follow-up visit, none developed clinical cholera during follow-up. The unadjusted single-dose vaccine effectiveness was 80·2% (95% CI 61·5-100·0) and after adjusting for potential confounders was 87·3% (70·2-100·0). One dose of Shanchol was effective in preventing medically attended cholera in this study. These results support the use of a single-dose strategy in outbreaks in similar epidemiological

Cohort Profile : LifeLines, a three-generation cohort study and biobank

NARCIS (Netherlands)

Scholtens, Salome; Smidt, Nynke; Swertz, Morris A.; Bakker, Stephan J. L.; Dotinga, Aafje; Vonk, Judith M.; van Dijk, Freerk; van Zon, Sander K. R.; Wijmenga, Cisca; Wolffenbuttel, Bruce H. R.; Stolk, Ronald P.

The LifeLines Cohort Study is a large population-based cohort study and biobank that was established as a resource for research on complex interactions between environmental, phenotypic and genomic factors in the development of chronic diseases and healthy ageing. Between 2006 and 2013, inhabitants

Incidence of anogenital warts in Germany: a population-based cohort study

Directory of Open Access Journals (Sweden)

Mikolajczyk Rafael T

2010-12-01

Full Text Available Abstract Background Human papilloma virus (HPV types 6 and 11 account for 90 percent of anogenital warts (AGW. Assessment of a potential reduction of the incidence of AGW following introduction of HPV vaccines requires population-based incidence rates. The aim of this study was to estimate incidence rates of AGW in Germany, stratified by age, sex, and region. Additionally, the medical practitioner (gynaecologist, dermatologist, urologist etc. who made the initial diagnosis of AGW was assessed. Methods Retrospective cohort study in a population aged 10 to 79 years in a population-based healthcare insurance database. The database included more than 14 million insurance members from all over Germany during the years 2004-2006. A case of AGW was considered incident if a disease-free period of twelve months preceded the diagnosis. To assess regional variation, analyses were performed by federal state. Results The estimated incidence rate was 169.5/100,000 person-years for the German population aged 10 to 79 years. Most cases occurred in the 15 to 40 years age group. The incidence rate was higher and showed a peak at younger ages in females than in males. The highest incidence rates for both sexes were observed in the city-states Berlin, Hamburg and Bremen. In females, initial diagnosis of AGW was most frequently made by a gynaecologist (71.7%, whereas in males, AGW were most frequently diagnosed by a dermatologist (44.8% or urologist (25.1%. Conclusions Incidence of AGW in Germany is comparable with findings for other countries. As expected, most cases occurred in the younger age groups. The frequency of diagnoses of AGW differs between sexes and women and men receive treatment by doctors of different specialties.

Fish intake and ovarian cancer risk: a meta-analysis of 15 case-control and cohort studies.

Directory of Open Access Journals (Sweden)

Pei-yue Jiang

Full Text Available BACKGROUND: Previous epidemiological studies have shown that fish consumption may modify the risk of ovarian cancer. However, these studies yielded controversial results. The present meta-analysis was undertaken to evaluate the relationship between fish intake and ovarian cancer risk. METHODS: A literature search was carried out using Pubmed, Embase, and Cochrane Library Central database for all relevant studies up to August 2013. We pooled the relative risks (RR from individual studies using fixed-effect or random-effect model, and carried out heterogeneity and publication bias analyses. RESULTS: A total of 15 (ten case-control, and five cohort studies were included in the present meta-analysis, representing data for 889,033 female subjects and 6,087 ovarian cancer cases. We found that total fish intake was not significantly associated with the risk of ovarian cancer among cohort studies (RR = 1.04 95% CI [0.89, 1.22] as well as case-control studies (RR = 0.90, 95% CI [0.73,1.12]. There was no evidence of publication bias as suggested by Begg's test (P = 0.55 and Egger's test(P = 0.29. CONCLUSIONS: The present meta-analysis showed that total fish consumption was not significantly associated with the risk of ovarian cancer. Further analysis on different fish species and food preparation methods should be conducted in future studies.

Premature death of adult adoptees: analyses of a case-cohort sample.

Science.gov (United States)

Petersen, Liselotte; Andersen, Per Kragh; Sørensen, Thorkild I A

2005-05-01

Genetic and environmental influence on risk of premature death in adulthood was investigated by estimating the associations in total and cause-specific mortality of adult Danish adoptees and their biological and adoptive parents. Among all 14,425 non-familial adoptions formally granted in Denmark during the period 1924 through 1947, we selected the study population according to a case-cohort sampling design. As the case-control design, the case-cohort design has the advantage of economic data collection and little loss in statistical efficiency, but the case-cohort sample has the additional advantages that rate ratio estimates may be obtained, and re-use of the cohort sample in future studies of other outcomes is possible. Analyses were performed using Kalbfleisch and Lawless's estimator for hazard ratio, and robust estimation for variances. In the main analyses the sample was restricted to birth years of the adoptees 1924 and after, and age of transfer to the adoptive parents before 7 years, and age at death was restricted to 16 to 70 years. The results showed a higher mortality among adoptees, whose biological parents died in the age range of 16 to 70 years; this was significant for deaths from natural causes, vascular causes and all causes. No influence was seen from early death of adoptive parents, regardless of cause of death. (c) 2005 Wiley-Liss, Inc.

Methodology Series Module 1: Cohort Studies.

Science.gov (United States)

Setia, Maninder Singh

2016-01-01

Cohort design is a type of nonexperimental or observational study design. In a cohort study, the participants do not have the outcome of interest to begin with. They are selected based on the exposure status of the individual. They are then followed over time to evaluate for the occurrence of the outcome of interest. Some examples of cohort studies are (1) Framingham Cohort study, (2) Swiss HIV Cohort study, and (3) The Danish Cohort study of psoriasis and depression. These studies may be prospective, retrospective, or a combination of both of these types. Since at the time of entry into the cohort study, the individuals do not have outcome, the temporality between exposure and outcome is well defined in a cohort design. If the exposure is rare, then a cohort design is an efficient method to study the relation between exposure and outcomes. A retrospective cohort study can be completed fast and is relatively inexpensive compared with a prospective cohort study. Follow-up of the study participants is very important in a cohort study, and losses are an important source of bias in these types of studies. These studies are used to estimate the cumulative incidence and incidence rate. One of the main strengths of a cohort study is the longitudinal nature of the data. Some of the variables in the data will be time-varying and some may be time independent. Thus, advanced modeling techniques (such as fixed and random effects models) are useful in analysis of these studies.

Methodology series module 1: Cohort studies

Directory of Open Access Journals (Sweden)

Maninder Singh Setia

2016-01-01

Full Text Available Cohort design is a type of nonexperimental or observational study design. In a cohort study, the participants do not have the outcome of interest to begin with. They are selected based on the exposure status of the individual. They are then followed over time to evaluate for the occurrence of the outcome of interest. Some examples of cohort studies are (1 Framingham Cohort study, (2 Swiss HIV Cohort study, and (3 The Danish Cohort study of psoriasis and depression. These studies may be prospective, retrospective, or a combination of both of these types. Since at the time of entry into the cohort study, the individuals do not have outcome, the temporality between exposure and outcome is well defined in a cohort design. If the exposure is rare, then a cohort design is an efficient method to study the relation between exposure and outcomes. A retrospective cohort study can be completed fast and is relatively inexpensive compared with a prospective cohort study. Follow-up of the study participants is very important in a cohort study, and losses are an important source of bias in these types of studies. These studies are used to estimate the cumulative incidence and incidence rate. One of the main strengths of a cohort study is the longitudinal nature of the data. Some of the variables in the data will be time-varying and some may be time independent. Thus, advanced modeling techniques (such as fixed and random effects models are useful in analysis of these studies.

Cohorts and community: a case study of community engagement in the establishment of a health and demographic surveillance site in Malaysia

Science.gov (United States)

Allotey, Pascale; Reidpath, Daniel D.; Devarajan, Nirmala; Rajagobal, Kanason; Yasin, Shajahan; Arunachalam, Dharmalingam; Imelda, Johanna Debora; Soyiri, Ireneous; Davey, Tamzyn; Jahan, Nowrozy

2014-01-01

Background Community engagement is an increasingly important requirement of public health research and plays an important role in the informed consent and recruitment process. However, there is very little guidance about how it should be done, the indicators for assessing effectiveness of the community engagement process and the impact it has on recruitment, retention, and ultimately on the quality of the data collected as part of longitudinal cohort studies. Methods An instrumental case study approach, with data from field notes, policy documents, unstructured interviews, and focus group discussions with key community stakeholders and informants, was used to explore systematically the implementation and outcomes of the community engagement strategy for recruitment of an entire community into a demographic and health surveillance site in Malaysia. Results For a dynamic cohort, community engagement needs to be an ongoing process. The community engagement process has likely helped to facilitate the current response rate of 85% in the research communities. The case study highlights the importance of systematic documentation of the community engagement process to ensure an understanding of the effects of the research on recruitment and the community. Conclusions A critical lesson from the case study data is the importance of relationships in the recruitment process for large population-based studies, and the need for ongoing documentation and analysis of the impact of cumulative interactions between research and community engagement. PMID:24804983

On estimation of time-dependent attributable fraction from population-based case-control studies.

Science.gov (United States)

Zhao, Wei; Chen, Ying Qing; Hsu, Li

2017-09-01

Population attributable fraction (PAF) is widely used to quantify the disease burden associated with a modifiable exposure in a population. It has been extended to a time-varying measure that provides additional information on when and how the exposure's impact varies over time for cohort studies. However, there is no estimation procedure for PAF using data that are collected from population-based case-control studies, which, because of time and cost efficiency, are commonly used for studying genetic and environmental risk factors of disease incidences. In this article, we show that time-varying PAF is identifiable from a case-control study and develop a novel estimator of PAF. Our estimator combines odds ratio estimates from logistic regression models and density estimates of the risk factor distribution conditional on failure times in cases from a kernel smoother. The proposed estimator is shown to be consistent and asymptotically normal with asymptotic variance that can be estimated empirically from the data. Simulation studies demonstrate that the proposed estimator performs well in finite sample sizes. Finally, the method is illustrated by a population-based case-control study of colorectal cancer. © 2017, The International Biometric Society.

A nested case-control study of influenza vaccination was a cost-effective alternative to a full cohort analysis

NARCIS (Netherlands)

Hak, E; Wei, F; Grobbee, D E; Nichol, K L

OBJECTIVE: In the absence of trial results that are applicable to the target population, nested case-control studies might be an alternative to full-cohort analysis. We compared relative and absolute estimates of associations in an influenza vaccine study using both designs. STUDY DESIGN AND

Candida Infective Endocarditis: an Observational Cohort Study with a Focus on Therapy

Science.gov (United States)

Johnson, Melissa; Bayer, Arnold S.; Bradley, Suzanne; Giannitsioti, Efthymia; Miró, José M.; Tornos, Pilar; Tattevin, Pierre; Strahilevitz, Jacob; Spelman, Denis; Athan, Eugene; Nacinovich, Francisco; Fortes, Claudio Q.; Lamas, Cristiane; Barsic, Bruno; Fernández-Hidalgo, Nuria; Muñoz, Patricia; Chu, Vivian H.

2015-01-01

Candida infective endocarditis is a rare disease with a high mortality rate. Our understanding of this infection is derived from case series, case reports, and small prospective cohorts. The purpose of this study was to evaluate the clinical features and use of different antifungal treatment regimens for Candida infective endocarditis. This prospective cohort study was based on 70 cases of Candida infective endocarditis from the International Collaboration on Endocarditis (ICE)-Prospective Cohort Study and ICE-Plus databases collected between 2000 and 2010. The majority of infections were acquired nosocomially (67%). Congestive heart failure (24%), prosthetic heart valve (46%), and previous infective endocarditis (26%) were common comorbidities. Overall mortality was high, with 36% mortality in the hospital and 59% at 1 year. On univariate analysis, older age, heart failure at baseline, persistent candidemia, nosocomial acquisition, heart failure as a complication, and intracardiac abscess were associated with higher mortality. Mortality was not affected by use of surgical therapy or choice of antifungal agent. A subgroup analysis was performed on 33 patients for whom specific antifungal therapy information was available. In this subgroup, 11 patients received amphotericin B-based therapy and 14 received echinocandin-based therapy. Despite a higher percentage of older patients and nosocomial infection in the echinocandin group, mortality rates were similar between the two groups. In conclusion, Candida infective endocarditis is associated with a high mortality rate that was not impacted by choice of antifungal therapy or by adjunctive surgical intervention. Additionally, echinocandin therapy was as effective as amphotericin B-based therapy in the small subgroup analysis. PMID:25645855

Using the entire history in the analysis of nested case cohort samples.

Science.gov (United States)

Rivera, C L; Lumley, T

2016-08-15

Countermatching designs can provide more efficient estimates than simple matching or case-cohort designs in certain situations such as when good surrogate variables for an exposure of interest are available. We extend pseudolikelihood estimation for the Cox model under countermatching designs to models where time-varying covariates are considered. We also implement pseudolikelihood with calibrated weights to improve efficiency in nested case-control designs in the presence of time-varying variables. A simulation study is carried out, which considers four different scenarios including a binary time-dependent variable, a continuous time-dependent variable, and the case including interactions in each. Simulation results show that pseudolikelihood with calibrated weights under countermatching offers large gains in efficiency if compared to case-cohort. Pseudolikelihood with calibrated weights yielded more efficient estimators than pseudolikelihood estimators. Additionally, estimators were more efficient under countermatching than under case-cohort for the situations considered. The methods are illustrated using the Colorado Plateau uranium miners cohort. Furthermore, we present a general method to generate survival times with time-varying covariates. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

[Ethical considerations in genomic cohort study].

Science.gov (United States)

Choi, Eun Kyung; Kim, Ock-Joo

2007-03-01

During the last decade, genomic cohort study has been developed in many countries by linking health data and genetic data in stored samples. Genomic cohort study is expected to find key genetic components that contribute to common diseases, thereby promising great advance in genome medicine. While many countries endeavor to build biobank systems, biobank-based genome research has raised important ethical concerns including genetic privacy, confidentiality, discrimination, and informed consent. Informed consent for biobank poses an important question: whether true informed consent is possible in population-based genomic cohort research where the nature of future studies is unforeseeable when consent is obtained. Due to the sensitive character of genetic information, protecting privacy and keeping confidentiality become important topics. To minimize ethical problems and achieve scientific goals to its maximum degree, each country strives to build population-based genomic cohort research project, by organizing public consultation, trying public and expert consensus in research, and providing safeguards to protect privacy and confidentiality.

Association of atrial fibrillation and cancer: Analysis from two large population-based case-control studies.

Science.gov (United States)

Saliba, Walid; Rennert, Hedy S; Gronich, Naomi; Gruber, Stephen B; Rennert, Gad

2018-01-01

An association between atrial fibrillation (AF) and risk of cancer has been suggested in several studies, including prospective cohort studies. However, the magnitude and the temporal nature of this association remain unclear. Data from two large prospective population-based case-control studies, the Molecular Epidemiology of Colorectal Cancer (MECC, n = 8,383) and the Breast Cancer in Northern Israel Study (BCINIS, n = 11,608), were used to better understand the nature and temporality of a possible association between cancer diagnosis and AF events before and after cancer diagnosis. A case-control study approach was employed to study prior AF as a risk factor for cancer, and a cohort study approach was employed to study incident cancer as a risk factor for AF. AF was associated with a significant reduced odds of cancer as reflected in the case-control approach, with an adjusted OR = 0.77 (95% CI, 0.65-0.91), while cancer was not found to be significantly associated with elevated risk of AF in the cohort approach, with an adjusted HR = 1.10 (0.98-1.23). The immediate period (90 days) after an AF event was associated with a 1.85 times increased risk of cancer, and the immediate period after the diagnosis of cancer was associated with a 3.4 fold increased risk of AF. These findings probably reflect both the effect of acute transient conditions associated with new cancer diagnosis and detection bias. Similar results were identified with colorectal and breast cancer cases. Atrial fibrillation of longer than 90 days duration is associated with reduced odds of new cancer diagnosis. The results of this study suggest that an association observed in prior research may be due to instances related to cancer diagnosis and detection bias rather than a causal relationship. However, there may be bias in the sampling and residual confounding that distort the associations.

Alcohol attributable burden of incidence of cancer in eight European countries based on results from prospective cohort study

NARCIS (Netherlands)

Schuetze, Madlen; Boeing, Heiner; Pischon, Tobias; Rehm, Juergen; Kehoe, Tara; Gmel, Gerrit; Olsen, Anja; Tjonneland, Anne M.; Dahm, Christina C.; Overvad, Kim; Clavel-Chapelon, Francoise; Boutron-Ruault, Marie-Christine; Trichopoulou, Antonia; Benetou, Vasiliki; Zylis, Dimosthenis; Kaaks, Rudolf; Rohrmann, Sabine; Palli, Domenico; Berrino, Franco; Tumino, Rosario; Vineis, Paolo; Rodriguez, Laudina; Agudo, Antonio; Sanchez, Maria-Jose; Dorronsoro, Miren; Chirlaque, Maria-Dolores; Barricarte, Aurelio; Peeters, Petra H.; van Gils, Carla H.; Khaw, Kay-Tee; Wareham, Nick; Allen, Naomi E.; Key, Timothy J.; Boffetta, Paolo; Slimani, Nadia; Jenab, Mazda; Romaguera, Dora; Wark, Petra A.; Riboli, Elio; Bergmann, Manuela M.

2011-01-01

Objective To compute the burden of cancer attributable to current and former alcohol consumption in eight European countries based on direct relative risk estimates from a cohort study. Design Combination of prospective cohort study with representative population based data on alcohol exposure.

Non-cancer morbidity among Estonian Chernobyl cleanup workers: a register-based cohort study.

Science.gov (United States)

Rahu, Kaja; Bromet, Evelyn J; Hakulinen, Timo; Auvinen, Anssi; Uusküla, Anneli; Rahu, Mati

2014-05-14

To examine non-cancer morbidity in the Estonian Chernobyl cleanup workers cohort compared with the population sample with special attention to radiation-related diseases and mental health disorders. Register-based cohort study. Estonia. An exposed cohort of 3680 men (cleanup workers) and an unexposed cohort of 7631 men (population sample) were followed from 2004 to 2012 through the Population Registry and Health Insurance Fund database. Morbidity in the exposed cohort compared with the unexposed controls was estimated in terms of rate ratio (RR) with 95% CIs using Poisson regression models. Elevated morbidity in the exposed cohort was found for diseases of the nervous system, digestive system, musculoskeletal system, ischaemic heart disease and for external causes. The most salient excess risk was observed for thyroid diseases (RR=1.69; 95% CI 1.38 to 2.07), intentional self-harm (RR=1.47; 95% CI 1.04 to 2.09) and selected alcohol-related diagnoses (RR=1.25; 95% CI 1.12 to 1.39). No increase in morbidity for stress reactions, depression, headaches or sleep disorders was detected. No obvious excess morbidity consistent with biological effects of radiation was seen in the exposed cohort, with the possible exception of benign thyroid diseases. Increased alcohol-induced morbidity may reflect alcohol abuse, and could underlie some of the higher morbidity rates. Mental disorders in the exposed cohort were probably under-reported. The future challenge will be to study mental and physical comorbidities in the Chernobyl cleanup workers cohort. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Design and conduct of an internet-based preconception cohort study in North America: Pregnancy Study Online (PRESTO)

Science.gov (United States)

Wise, Lauren A; Rothman, Kenneth J.; Mikkelsen, Ellen M.; Stanford, Joseph B.; Wesselink, Amelia K.; McKinnon, Craig; Gruschow, Siobhan M.; Horgan, Casie E.; Wiley, Aleta S.; Hahn, Kristen A.; Sørensen, Henrik Toft; Hatch, Elizabeth E.

2015-01-01

Background We launched the Boston University Pregnancy Study Online (PRESTO) to assess the feasibility of carrying out an internet-based preconception cohort study in the U.S. and Canada. Methods We recruited female participants age 21–45 and their male partners through internet advertisements, word of mouth, and flyers. Female participants were randomized with 50% probability to receive a subscription to FertilityFriend.com (FF), a web-based program that collects real-time data on menstrual characteristics. We compared recruitment methods within PRESTO, assessed the cost-efficiency of PRESTO relative to its Danish counterpart (Snart-Gravid), and validated retrospectively-reported date of last menstrual period (LMP) against FF data. Results After 99 weeks of recruitment (2013–2015), 2,421 women enrolled; 1,384 (57%) invited their male partners to participate, of whom 693 (50%) enrolled. Baseline characteristics were balanced across randomization groups. Cohort retention was similar among those randomized vs. not randomized to FF (84% vs. 81%). At study enrollment, 56%, 22%, and 22% couples had been trying to conceive for cost per subject enrolled was $146 (2013 $US), which was similar to our companion Danish study and half that of a traditional cohort study. Among FF users who conceived, >97% reported their LMP on the PRESTO questionnaire within 1 day of the LMP recorded via FF. Conclusions Use of the internet as a method of recruitment and follow-up in a North American preconception cohort study was feasible and cost-effective. PMID:26111445

Cardiac-surgery associated acute kidney injury requiring renal replacement therapy. A Spanish retrospective case-cohort study

Directory of Open Access Journals (Sweden)

Garcia-Fernandez Nuria

2009-09-01

Full Text Available Abstract Background Acute kidney injury is among the most serious complications after cardiac surgery and is associated with an impaired outcome. Multiple factors may concur in the development of this disease. Moreover, severe renal failure requiring renal replacement therapy (RRT presents a high mortality rate. Consequently, we studied a Spanish cohort of patients to assess the risk factors for RRT in cardiac surgery-associated acute kidney injury (CSA-AKI. Methods A retrospective case-cohort study in 24 Spanish hospitals. All cases of RRT after cardiac surgery in 2007 were matched in a crude ratio of 1:4 consecutive patients based on age, sex, treated in the same year, at the same hospital and by the same group of surgeons. Results We analyzed the data from 864 patients enrolled in 2007. In multivariate analysis, severe acute kidney injury requiring postoperative RRT was significantly associated with the following variables: lower glomerular filtration rates, less basal haemoglobin, lower left ventricular ejection fraction, diabetes, prior diuretic treatment, urgent surgery, longer aortic cross clamp times, intraoperative administration of aprotinin, and increased number of packed red blood cells (PRBC transfused. When we conducted a propensity analysis using best-matched of 137 available pairs of patients, prior diuretic treatment, longer aortic cross clamp times and number of PRBC transfused were significantly associated with CSA-AKI. Patients requiring RRT needed longer hospital stays, and suffered higher mortality rates. Conclusion Cardiac-surgery associated acute kidney injury requiring RRT is associated with worse outcomes. For this reason, modifiable risk factors should be optimised and higher risk patients for acute kidney injury should be identified before undertaking cardiac surgery.

Candida infective endocarditis: an observational cohort study with a focus on therapy.

Science.gov (United States)

Arnold, Christopher J; Johnson, Melissa; Bayer, Arnold S; Bradley, Suzanne; Giannitsioti, Efthymia; Miró, José M; Tornos, Pilar; Tattevin, Pierre; Strahilevitz, Jacob; Spelman, Denis; Athan, Eugene; Nacinovich, Francisco; Fortes, Claudio Q; Lamas, Cristiane; Barsic, Bruno; Fernández-Hidalgo, Nuria; Muñoz, Patricia; Chu, Vivian H

2015-04-01

Candida infective endocarditis is a rare disease with a high mortality rate. Our understanding of this infection is derived from case series, case reports, and small prospective cohorts. The purpose of this study was to evaluate the clinical features and use of different antifungal treatment regimens for Candida infective endocarditis. This prospective cohort study was based on 70 cases of Candida infective endocarditis from the International Collaboration on Endocarditis (ICE)-Prospective Cohort Study and ICE-Plus databases collected between 2000 and 2010. The majority of infections were acquired nosocomially (67%). Congestive heart failure (24%), prosthetic heart valve (46%), and previous infective endocarditis (26%) were common comorbidities. Overall mortality was high, with 36% mortality in the hospital and 59% at 1 year. On univariate analysis, older age, heart failure at baseline, persistent candidemia, nosocomial acquisition, heart failure as a complication, and intracardiac abscess were associated with higher mortality. Mortality was not affected by use of surgical therapy or choice of antifungal agent. A subgroup analysis was performed on 33 patients for whom specific antifungal therapy information was available. In this subgroup, 11 patients received amphotericin B-based therapy and 14 received echinocandin-based therapy. Despite a higher percentage of older patients and nosocomial infection in the echinocandin group, mortality rates were similar between the two groups. In conclusion, Candida infective endocarditis is associated with a high mortality rate that was not impacted by choice of antifungal therapy or by adjunctive surgical intervention. Additionally, echinocandin therapy was as effective as amphotericin B-based therapy in the small subgroup analysis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The Congenital Heart Disease Genetic Network Study: Cohort description.

Directory of Open Access Journals (Sweden)

Thanh T Hoang

Full Text Available The Pediatric Cardiac Genomics Consortium (PCGC designed the Congenital Heart Disease Genetic Network Study to provide phenotype and genotype data for a large congenital heart defects (CHDs cohort. This article describes the PCGC cohort, overall and by major types of CHDs (e.g., conotruncal defects and subtypes of conotrucal heart defects (e.g., tetralogy of Fallot and left ventricular outflow tract obstructions (e.g., hypoplastic left heart syndrome. Cases with CHDs were recruited through ten sites, 2010-2014. Information on cases (N = 9,727 and their parents was collected through interviews and medical record abstraction. Four case characteristics, eleven parental characteristics, and thirteen parent-reported neurodevelopment outcomes were summarized using counts and frequencies and compared across CHD types and subtypes. Eleven percent of cases had a genetic diagnosis. Among cases without a genetic diagnosis, the majority had conotruncal heart defects (40% or left ventricular outflow tract obstruction (21%. Across CHD types, there were significant differences (p<0.05 in the distribution of all four case characteristics (e.g., sex, four parental characteristics (e.g., maternal pregestational diabetes, and five neurodevelopmental outcomes (e.g., learning disabilities. Several characteristics (e.g., sex were also significantly different across CHD subtypes. The PCGC cohort is one of the largest CHD cohorts available for the study of genetic determinants of risk and outcomes. The majority of cases do not have a genetic diagnosis. This description of the PCGC cohort, including differences across CHD types and subtypes, provides a reference work for investigators who are interested in collaborating with or using publically available resources from the PCGC.

Hyperthyroidism and female urinary incontinence: a population-based cohort study.

Science.gov (United States)

Chung, Shiu-Dong; Chen, Yi-Kuang; Chen, Yi-Hua; Lin, Herng-Ching

2011-11-01

The imbalanced autonomic nervous system present in hyperthyroidism may cause lower urinary tract symptoms. Urinary incontinence (UI) is the most bothersome lower urinary tract symptom; however, in the literature, reports regarding urinary dysfunction and/or incontinence among hyperthyroid patients are scarce. This population-based cohort study aimed to examine the relationship between hyperthyroidism in women and the risk of developing UI in Taiwan. This study used data from the Longitudinal Health Insurance Database. For this study, 10,817 female patients diagnosed with hyperthyroidism from 2001 to 2005 were recruited together with a comparison cohort of 54,085 matched enrollees who did not have a history of hyperthyroidism. All patients were tracked for a 3-year period from their index date to identify those who had a subsequent UI. The stratified Cox proportional hazards models were used to compute the risk of UI between study and comparison cohorts. During the follow-up period, of 64,169 patients, 173 (1·60%) from the hyperthyroidism group and 560 (1·04%) from the comparison group, had a diagnosis of UI. The regression analysis showed that, after adjusting for monthly income, geographic region, urbanization level of the community in which the patient resided, obesity and hysterectomy, patients with hyperthyroidism were more likely to have UI during the 3-year follow-up period than the comparison patients (hazard ratio = 1·54; 95% CI = 1·30-1·83; P hyperthyroidism at the 3-year follow-up. © 2011 Blackwell Publishing Ltd.

Risk of erectile dysfunction in transfusion-naive thalassemia men: a nationwide population-based retrospective cohort study.

Science.gov (United States)

Chen, Yu-Guang; Lin, Te-Yu; Lin, Cheng-Li; Dai, Ming-Shen; Ho, Ching-Liang; Kao, Chia-Hung

2015-04-01

Based on the mechanism of pathophysiology, thalassemia major or transfusion-dependent thalassemia patients may have an increased risk of developing organic erectile dysfunction resulting from hypogonadism. However, there have been few studies investigating the association between erectile dysfunction and transfusion-naive thalassemia populations. We constructed a population-based cohort study to elucidate the association between transfusion-naive thalassemia populations and organic erectile dysfunction. This nationwide population-based cohort study involved analyzing data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified men with transfusion-naive thalassemia and selected a comparison cohort that was frequency-matched with these according to age, and year of diagnosis thalassemia at a ratio of 1 thalassemia man to 4 control men. We analyzed the risks for transfusion-naive thalassemia men and organic erectile dysfunction by using Cox proportional hazards regression models. In this study, 588 transfusion-naive thalassemia men and 2337 controls were included. Total 12 patients were identified within the thalassaemia group and 10 within the control group. The overall risks for developing organic erectile dysfunction were 4.56-fold in patients with transfusion-naive thalassemia men compared with the comparison cohort after we adjusted for age and comorbidities. Our long-term cohort study results showed that in transfusion-naive thalassemia men, there was a higher risk for the development of organic erectile dysfunction, particularly in those patients with comorbidities.

The Danish National Birth Cohort

DEFF Research Database (Denmark)

Andersen, Anne-Marie Nybo; Olsen, Jørn

2011-01-01

, physical exercise, working conditions, medication and infections during pregnancy, and environmental possible toxins. The study designs cover straightforward cohort analyses, case-control studies and sub-cohort analyses with enriched data collection. CONCLUSION: So far, the Danish National Birth Cohort has......INTRODUCTION: In this review a selection of studies published during the period 2002-2010, based on data from the Danish National Birth Cohort linked with other health registers, is described. Illustrative examples of studies addressing perinatal health outcomes (pregnancy complications and fetal...... that this investment in epidemiologic infrastructure was well spent. The existence of the Danish National Birth Cohort together with other cohorts and national registers has given Denmark a leading position in reproductive epidemiology....

Smoking and risk of acute and chronic pancreatitis among women and men: a population-based cohort study

DEFF Research Database (Denmark)

Tolstrup, Janne Schurmann; Kristiansen, Louise; Becker, Ulrik

2009-01-01

BACKGROUND: Alcohol and gallstone disease are the most established risk factors for pancreatitis. Smoking is rarely considered to be a cause despite the fact that a few studies have indicated the opposite. We aimed to assess the independent effects of smoking on the risk of pancreatitis. METHODS......: We used data from an observational, population-based cohort study conducted in Denmark. Participants were 9573 women and 8332 men who were followed up for a mean of 20.2 years. Participants underwent a physical examination and completed self-administered questionnaires about lifestyle habits....... Information on incident cases of acute and chronic pancreatitis were obtained by record linkage with the Danish national registries. RESULTS: A total of 235 cases of pancreatitis occurred during follow-up. A dose-response association between smoking and risk of acute and chronic pancreatitis was observed...

Primary Sjogren's syndrome and the risk of acute pancreatitis: a nationwide cohort study.

Science.gov (United States)

Chang, Chi-Ching; Chang, Yu-Sheng; Wang, Shu-Hung; Lin, Shyr-Yi; Chen, Yi-Hsuan; Chen, Jin Hua

2017-08-11

Studies on the risk of acute pancreatitis in patients with primary Sjogren's syndrome (pSS) are limited. We evaluated the effects of pSS on the risk of acute pancreatitis in a nationwide, population-based cohort in Taiwan. Population-based retrospective cohort study. We studied the claims data of the >97% Taiwan population from 2002 to 2012. We identified 9468 patients with pSS by using the catastrophic illness registry of the National Health Insurance Database in Taiwan. We also selected 37 872 controls that were randomly frequency matched by age (in 5 year bands), sex and index year from the general population. We analysed the risk of acute pancreatitis by using Cox proportional hazards regression models including sex, age and comorbidities. From 23.74 million people in the cohort, 9468 patients with pSS (87% women, mean age=55.6 years) and 37 872 controls were followed-up for 4.64 and 4.74 years, respectively. A total of 44 cases of acute pancreatitis were identified in the pSS cohort versus 105 cases in the non-pSS cohort. Multivariate Cox regression analysis indicated that the incidence rate of acute pancreatitis was significantly higher in the pSS cohort than in the non-pSS cohort (adjusted HR (aHR) 1.48, 95% CI 1.03 to 2.12). Cyclophosphamide use increased the risk of acute pancreatitis (aHR 5.27, 95% CI 1.16 to 23.86). By contrast, hydroxychloroquine reduced the risk of acute pancreatitis (aHR 0.23, 95% CI 0.09 to 0.55). This nationwide, retrospective cohort study demonstrated that the risk of acute pancreatitis was significantly higher in patients with pSS than in the general population. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Risk of lymphoma and leukaemia after bacille Calmette-Guérin and smallpox vaccination: a Danish case-cohort study

DEFF Research Database (Denmark)

Villumsen, Marie; Sørup, Signe; Jess, Tine

2009-01-01

Vaccines may have non-specific effects as suggested mainly in mortality studies from low-income countries. The objective was to examine the effects of BCG and smallpox vaccinations on subsequent risk of lymphoma and leukaemia in a Danish population experiencing rapid out-phasing of these vaccines...... cohort and analysed in a case-cohort design. BCG vaccination reduced the risk of lymphomas (HR=0.49 (95% CI: 0.26-0.93)), whereas smallpox vaccination did not (HR=1.32 (0.56-3.08)). With the small number of leukaemia cases, the analysis of leukaemia had limited power (BCG vaccination HR=0.81 (0.......31-2.16); smallpox vaccination HR=1.32 (0.49-3.53)). The present study with very reliable vaccine history information indicates a beneficial effect of BCG vaccination on the risk of lymphomas....

The case for launch of an international DNA based birth cohort study

Directory of Open Access Journals (Sweden)

Igor Rudan

2011-06-01

Full Text Available The global health agenda beyond 2015 will inevitably need to broaden its focus from mortality reduction to the social determinants of deaths, growing inequities among children and mothers, and ensuring the sustainability of the progress made against the infectious diseases. New research tools, including technologies that enable high-throughput genetic and ‘-omics’ research, could be deployed for better understanding of the aetiology of maternal and child health problems. The research needed to address those challenges will require conceptually different studies than those used in the past. It should be guided by stringent ethical frameworks related to the emerging collections of biological specimens and other health related information. We will aim to establish an international birth cohort which should assist low- and middle-income countries to use emerging genomic research technologies to address the main problems in maternal and child health, which are still major contributors to the burden of disease globally.

Population-based imaging and radiomics. Rational and perspective of the German National Cohort MRI study

International Nuclear Information System (INIS)

Schlett, C.L.; Weckbach, S.; Hendel, T.

2016-01-01

The MRI study within the German National Cohort, a large-scale, population-based, longitudinal study in Germany, comprises comprehensive characterization and phenotyping of a total of 30 000 participants using 3-Tesla whole-body MR imaging. A multi-centric study design was established together with dedicated core facilities for e.g. managing incidental findings or providing quality assurance. As such, the study represents a unique opportunity to substantially impact imaging-based risk stratification leading to personalized and precision medicine. Supported by the developments in the field of computational science, the newly developing scientific field of radiomics has large potential for the future. In the present article we provide an overview on population-based imaging and Radiomics and conceptualize the rationale and design of the MRI study within the German National Cohort.

Recipient Age and Mortality Risk after Liver Transplantation: A Population-Based Cohort Study.

Science.gov (United States)

Chen, Hsiu-Pin; Tsai, Yung-Fong; Lin, Jr-Rung; Liu, Fu-Chao; Yu, Huang-Ping

2016-01-01

The aim of the present large population-based cohort study is to explore the risk factors of age-related mortality in liver transplant recipients in Taiwan. Basic information and data on medical comorbidities for 2938 patients who received liver transplants between July 1, 1998, and December 31, 2012, were extracted from the National Health Insurance Research Database on the basis of ICD-9-codes. Mortality risks were analyzed after adjusting for preoperative comorbidities and compared among age cohorts. All patients were followed up until the study endpoint or death. This study finally included 2588 adults and 350 children [2068 (70.4%) male and 870 (29.6%) female patients]. The median age at transplantation was 52 (interquartile range, 43-58) years. Recipients were categorized into the following age cohorts: recipients (≥60 years), especially dialysis patients, have a higher mortality rate, possibly because they have more medical comorbidities. Our findings should make clinicians aware of the need for better risk stratification among elderly liver transplantation candidates.

Malignant transformation of oral submucous fibrosis in Taiwan: A nationwide population-based retrospective cohort study.

Science.gov (United States)

Yang, Po-Yu; Chen, Yi-Tzu; Wang, Yu-Hsun; Su, Ni-Yu; Yu, Hui-Chieh; Chang, Yu-Chao

2017-11-01

Oral submucous fibrosis (OSF) is one of the well-recognized oral potentially malignant disorders. In this study, we investigated the malignant transformation of OSF in a Taiwanese population. A retrospective cohort study was analyzed from Taiwan's National Health Insurance Research Database. A comparison cohort was randomly frequency-matched with the OSF cohort according to age, sex, and index year. Oral leukoplakia (OL) was further stratified to evaluate for the possible synergistic effects of OSF-associated malignant transformation. In this cohort, 71 (9.13%) of 778 cases of OSF were observed to transform into oral cancer. The malignant transformation rate was 29.26-fold in the OSF cohort than in the comparison cohort after adjustment (95% confidence intervals 20.55-41.67). To further stratify with OL, OSF with OL (52.46%; 95% confidence intervals 34.88-78.91) had higher risk of malignant transformation rate than OSF alone (29.84%; 95% confidence intervals 20.99-42.42). The Kaplan-Meier plot revealed the rate free of malignant transformation was significant over the 13-year follow-up period (log-rank test, Ptransformation was 5.1, 2.7, and 2.2 years for non-OSF, OSF alone, and OSF with OL, respectively. Oral submucous fibrosis patients exhibited a significantly higher risk of malignant transformation than those without OSF. OL could enhance malignant transformation in patients with OSF. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Association of Adiponectin With Cancer and All-Cause Mortality in a Japanese Community-Dwelling Elderly Cohort: A Case-Cohort Study.

Science.gov (United States)

Kojima, Reiji; Ukawa, Shigekazu; Zhao, Wenjing; Suzuki, Koji; Yamada, Hiroya; Tsushita, Kazuyo; Kawamura, Takashi; Okabayashi, Satoe; Wakai, Kenji; Noma, Hisashi; Ando, Masahiko; Tamakoshi, Akiko

2018-03-24

Most studies of plasma adiponectin (APN) and mortality among community-dwelling elderly focus on cardiovascular disease, but data on the relationship between plasma APN and cancer mortality is exiguous. We investigated whether APN is associated with cancer mortality in community-dwelling elderly people. We conducted a case-cohort study within the New Integrated Suburban Seniority Investigation (NISSIN) Project using a randomly drawn sub-cohort of 697 subjects (351 men and 346 women; mean age 64.5 [standard deviation, 0.5] years) among whom we compared cases of all-cause death (n = 269) and cancer death (n = 149) during a mean follow-up duration of 10.8 (standard deviation, 3.7) years. Associations between APN and mortality were assessed using weighted Cox regression analyses. We observed significant positive associations between the APN concentration and cancer death in the first and third APN tertiles compared with the second APN tertile (hazard ratio [HR] T1 vs T2 , 1.67; 95% confidence interval [CI], 1.00-2.79 and HR T3 vs T2 , 2.10; 95% CI, 1.30-3.40). Further adjustment for possible confounders attenuated the association (HR T1 vs T2 , 1.63; 95% CI, 0.93-2.84 and HR T3 vs T2 , 2.10; 95% CI, 1.26-3.50). A similar but weaker association was seen for all-cause mortality (multivariate HR T1 vs T2 , 1.45; 95% CI, 0.95-2.21 and HR T3 vs T2 , 1.51; 95% CI, 1.01-2.25). Plasma APN and cancer mortality have a significant relationship among community-dwelling elderly people, which warrants further study.

Lack of Association Between Maternal or Neonatal Vitamin D Status and Risk of Childhood Type 1 Diabetes: A Scandinavian Case-Cohort Study.

Science.gov (United States)

Thorsen, Steffen U; Mårild, Karl; Olsen, Sjurdur F; Holst, Klaus K; Tapia, German; Granström, Charlotta; Halldorsson, Thorhallur I; Cohen, Arieh S; Haugen, Margaretha; Lundqvist, Marika; Skrivarhaug, Torild; Njølstad, Pål R; Joner, Geir; Magnus, Per; Størdal, Ketil; Svensson, Jannet; Stene, Lars C

2018-06-01

Studies on vitamin D status during pregnancy and risk of type 1 diabetes mellitus (T1D) lack consistency and are limited by small sample sizes or single measures of 25-hydroxyvitamin D (25(OH)D). We investigated whether average maternal 25(OH)D plasma concentrations during pregnancy are associated with risk of childhood T1D. In a case-cohort design, we identified 459 children with T1D and a random sample (n = 1,561) from the Danish National Birth Cohort (n = 97,127) and Norwegian Mother and Child Cohort Study (n = 113,053). Participants were born between 1996 and 2009. The primary exposure was the estimated average 25(OH)D concentration, based on serial samples from the first trimester until delivery and on umbilical cord plasma. We estimated hazard ratios using weighted Cox regression adjusting for multiple confounders. The adjusted hazard ratio for T1D per 10-nmol/L increase in the estimated average 25(OH)D concentration was 1.00 (95% confidence interval: 0.90, 1.10). Results were consistent in both cohorts, in multiple sensitivity analyses, and when we analyzed mid-pregnancy or cord blood separately. In conclusion, our large study demonstrated that normal variation in maternal or neonatal 25(OH)D is unlikely to have a clinically important effect on risk of childhood T1D.

E-learning may improve adherence to alcohol-based hand rubbing: a cohort study

DEFF Research Database (Denmark)

Laustsen, Sussie; Bibby, Bo Martin; Kristensen, Brian

2009-01-01

BACKGROUND: Since 2004, we have promoted alcohol-based hand rubbing (HR) with an e-learning program (ELP) among hospital staff. This study sought to determine whether an ELP improves adherence to correct HR. METHODS: This was a cohort study of staff members at Aarhus University Hospital, Skejby, ...

Incidence of hand eczema in a population-based twin cohort

DEFF Research Database (Denmark)

Lerbaek, A; Kyvik, Kirsten Ohm; Ravn, H

2007-01-01

BACKGROUND: Population-based studies on the incidence of hand eczema are sparse. OBJECTIVES: The aim of this prospective follow-up study was to determine the incidence rate of hand eczema in a population-based twin cohort. Secondly, the role of genetic factors and other potential risk factors...... for hand eczema was investigated. METHODS: A questionnaire on self-reported hand eczema was answered by 5610 and 4128 twin individuals in 1996 and 2005, respectively. Data were analysed in a Poisson regression analysis. RESULTS: The crude incidence rate was 8.8 cases per 1000 person-years (95% confidence...... with an increased risk, whereas no association with age, sex, smoking or alcohol was found...

Trends in Dementia Incidence in a Birth Cohort Analysis of the Einstein Aging Study.

Science.gov (United States)

Derby, Carol A; Katz, Mindy J; Lipton, Richard B; Hall, Charles B

2017-11-01

Trends in dementia incidence rates have important implications for planning and prevention. To better understand incidence trends over time requires separation of age and cohort effects, and few prior studies have used this approach. To examine trends in dementia incidence and concomitant trends in cardiovascular comorbidities among individuals aged 70 years or older who were enrolled in the Einstein Aging Study between 1993 and 2015. In this birth cohort analysis of all-cause dementia incidence in persons enrolled in the Einstein Aging Study from October 20, 1993, through November 17, 2015, a systematically recruited, population-based sample of 1348 participants from Bronx County, New York, who were 70 years or older without dementia at enrollment and at least one annual follow-up was studied. Poisson regression was used to model dementia incidence as a function of age, sex, educational level, race, and birth cohort, with profile likelihood used to identify the timing of significant increases or decreases in incidence. Birth year and age. Incident dementia defined by consensus case conference based on annual, standardized neuropsychological and neurologic examination findings, using criteria from the DSM-IV. Among 1348 individuals (mean [SD] baseline age, 78.5 [5.4] years; 830 [61.6%] female; 915 [67.9%] non-Hispanic white), 150 incident dementia cases developed during 5932 person-years (mean [SD] follow-up, 4.4 [3.4] years). Dementia incidence decreased in successive birth cohorts. Incidence per 100 person-years was 5.09 in birth cohorts before 1920, 3.11 in the 1920 through 1924 birth cohorts, 1.73 in the 1925 through 1929 birth cohorts, and 0.23 in cohorts born after 1929. Change point analyses identified a significant decrease in dementia incidence among those born after July 1929 (95% CI, June 1929 to January 1930). The relative rate for birth cohorts before July 1929 vs after was 0.13 (95% CI, 0.04-0.41). Prevalence of stroke and myocardial infarction

Vegetarianism, low meat consumption and the risk of colorectal cancer in a population based cohort study.

Science.gov (United States)

Gilsing, Anne M J; Schouten, Leo J; Goldbohm, R Alexandra; Dagnelie, Pieter C; van den Brandt, Piet A; Weijenberg, Matty P

2015-08-28

To study how a vegetarian or low meat diet influences the risk of colorectal cancer compared to a high meat diet, and to assess the explanatory role of factors associated with these diets. In the Netherlands Cohort Study - Meat Investigation Cohort (NLCS-MIC) (cohort of 10,210 individuals including 1040 self-defined vegetarians), subjects completed a baseline questionnaire in 1986, based on which they were classified into vegetarians (n = 635), pescetarians (n = 360), 1 day/week- (n = 1259), 2-5 day/week- (n = 2703), and 6-7 day/week meat consumers (n = 5253). After 20.3 years of follow-up, 437 colorectal cancer cases (307 colon, 92 rectal) were available. A non-significantly decreased risk of CRC for vegetarians, pescetarians, and 1 day/week compared to 6-7 day/week meat consumers was observed (age/sex adjusted Hazard Ratios (HR): 0.73(0.47-1.13), 0.80(0.47-1.39), and 0.72(0.52-1.00), respectively). Most of the differences in HR between these groups could be explained by intake of dietary fiber and soy products. Other (non-)dietary factors characteristic for a vegetarian or low meat diet had negligible individual effects, but attenuated the HRs towards the null when combined. Vegetarians, pescetarians, and 1 day/week meat eaters showed a non-significantly decreased risk of colorectal cancer compared to 6-7 day/week meat consumers, mainly due to differences in dietary pattern other than meat intake.

Risk of thyroid cancer in patients with thyroiditis: a population-based cohort study.

Science.gov (United States)

Liu, Chien-Liang; Cheng, Shih-Ping; Lin, Hui-Wen; Lai, Yuen-Liang

2014-03-01

The causative relationship between autoimmune thyroiditis and thyroid cancer remains a controversial issue. The aim of this population-based study was to investigate the risk of thyroid cancer in patients with thyroiditis. From the Longitudinal Health Insurance Database 2005 (LHID2005) of Taiwan, we identified adult patients newly diagnosed with thyroiditis between 2004 and 2009 (n = 1,654). The comparison cohort (n = 8,270) included five randomly selected age- and sex-matched controls for each patient in the study cohort. All patients were followed up from the date of cohort entry until they developed thyroid cancer or to the end of 2010. Multivariate Cox regression was used to assess the risk of developing thyroid cancer. A total of 1,000 bootstrap replicates were created for internal validation. A total of 35 patients developed thyroid cancer during the study period, of whom 24 were from the thyroiditis cohort and 11 were from the comparison cohort (incidence 353 and 22 per 100,000 person-years, respectively). After adjusting for potential confounding factors, the hazard ratio (HR) for thyroid cancer in patients with thyroiditis was 13.24 (95 % CI 6.40-27.39). Excluding cancers occurring within 1 year of follow-up, the HR remained significantly increased (6.64; 95 % CI 2.35-18.75). Hypothyroidism was not an independent factor associated with the occurrence of thyroid cancer. We found an increased risk for the development of thyroid cancer after a diagnosis of thyroiditis, independent of comorbidities.

Cohorts based on decade of death: no evidence for secular trends favoring later cohorts in cognitive aging and terminal decline in the AHEAD study.

Science.gov (United States)

Hülür, Gizem; Infurna, Frank J; Ram, Nilam; Gerstorf, Denis

2013-03-01

Studies of birth-year cohorts examined over the same age range often report secular trends favoring later-born cohorts, who are cognitively fitter and show less steep cognitive declines than earlier-born cohorts. However, there is initial evidence that those advantages of later-born cohorts do not carry into the last years of life, suggesting that pervasive mortality-related processes minimize differences that were apparent earlier in life. Elaborating this work from an alternative perspective on cohort differences, we compared rates of cognitive aging and terminal decline in episodic memory between cohorts based on the year participants had died, earlier (between 1993 and 1999) or later in historical time (between 2000 and 2010). Specifically, we compared trajectories of cognitive decline in 2 death-year cohorts of participants in the Asset and Health Dynamics Among the Oldest Old study that were matched on age at death and education and controlled for a variety of additional covariates. Results revealed little evidence of secular trends favoring later cohorts. To the contrary, the cohort that died in the 2000s showed a less favorable trajectory of age-related memory decline than the cohort that died in the 1990s. In examinations of change in relation to time to death, the cohort dying in the 2000s experienced even steeper terminal declines than the cohort dying in the 1990s. We suggest that secular increases in "manufacturing" survival may exacerbate age- and mortality-related cognitive declines among the oldest old.

Sleep apnea and risk of vertigo: A nationwide population-based cohort study.

Science.gov (United States)

Tsai, Ming-Shao; Lee, Li-Ang; Tsai, Yao-Te; Yang, Yao-Hsu; Liu, Chia-Yen; Lin, Meng-Hung; Hsu, Cheng-Ming; Chen, Chin-Kuo; Li, Hsueh-Yu

2018-03-01

To investigate the risk of vertigo in patients with sleep apnea. Retrospective cohort study. This study used data from the National Health Insurance Research Database of Taiwan, a population-based database. A total of 5,025 patients who were newly diagnosed with sleep apnea between January 1, 1997, and December 31, 2012, were identified from the Longitudinal Health Insurance Database 2000, a nationally representative database of 1 million randomly selected patients. Moreover, 20,100 patients without sleep apnea were matched at a 1:4 ratio by age, sex, socioeconomic status, and urbanization level. Patients were followed up until death or the end of the study period (December 31, 2013). The primary outcome was the occurrence of vertigo. Patients with sleep apnea had a significantly higher cumulative incidence of vertigo than those without sleep apnea (P vertigo (hazard ratio, 1.71; 95% confidence interval [CI], 1.48-1.97; P diabetes mellitus, hypertension, stroke, and obesity. Sleep apnea was demonstrated to be an independent risk factor for vertigo. This is the first nationwide population-based cohort study to investigate the association between sleep apnea and vertigo. The findings strongly support that sleep apnea is an independent risk factor for vertigo. Based on the study results, physicians should be aware of potential vertigo occurrence following sleep apnea. 4. Laryngoscope, 128:763-768, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Impact of organised mammography screening on breast cancer mortality in a case–control and cohort study

Science.gov (United States)

Heinävaara, Sirpa; Sarkeala, Tytti; Anttila, Ahti

2016-01-01

Background: The usefulness of case–control studies has been questioned. Our aim was to evaluate the long-term effect of screening on breast cancer mortality within the population-based mammography programme in Finland using a case–control design, and to compare the analyses with the earlier cohort study. Methods: The cases were women invited to screening, diagnosed and died from breast cancer in 1992–2011 while being 50–84 years at death. We chose 10 controls for each case with non-restrictive eligibility criteria. Our data included 1907 cases and 18 978 matched controls. We analysed associations between the screening participation and the risk of breast cancer death using the conditional Cox proportional hazards model. The effect estimates were corrected for self-selection bias. Results: An overall effect of screening was 0.67 (95% confidence interval (CI): 0.49–0.90), and that remained unchanged over time. Analyses with matching criteria comparable to the cohort study yielded an effect (0.70, 95% CI: 0.49–1.00) in 1992–2003 similar to that of the previous cohort analysis (0.72, 95% CI: 0.56–0.88). Conclusions: Organised mammography screening decreases mortality from breast cancer by 33% among the participants. If made comparable, a case–cohort study can yield effect estimates similar to a cohort study. PMID:27010748

Dementia and Traffic Accidents: A Danish Register-Based Cohort Study.

Science.gov (United States)

Petersen, Jindong Ding; Siersma, Volkert; Nielsen, Connie Thurøe; Vass, Mikkel; Waldorff, Frans Boch

2016-09-27

As a consequence of a rapid growth of an ageing population, more people with dementia are expected on the roads. Little is known about whether these people are at increased risk of road traffic-related accidents. Our study aims to investigate the risk of road traffic-related accidents for people aged 65 years or older with a diagnosis of dementia in Denmark. We will conduct a nationwide population-based cohort study consisting of Danish people aged 65 or older living in Denmark as of January 1, 2008. The cohort is followed for 7 years (2008-2014). Individual's personal data are available in Danish registers and can be linked using a unique personal identification number. A person is identified with dementia if the person meets at least one of the following criteria: (1) a diagnosis of the disease in the Danish National Patient Register or in the Danish Psychiatric Central Research Register, and/or (2) at least one dementia diagnosis-related drug prescription registration in the Danish National Prescription Registry. Police-, hospital-, and emergency room-reported road traffic-related accidents occurred within the study follow-up are defined as the study outcome. Cox proportional hazard regression models are used for the main analysis. Our study protocol has 3 phases including data collection, data analysis, and reporting. The first phase of register-based data collection of 853,228 individual's personal information was completed in August, 2016. The next phase is data analysis, which is expected to be finished before December 2016, and thereafter writing publications based on the findings. The study started in January 2016 and will end in December 2018. This study covers the entire elderly population of Denmark, and thereby will avoid selection bias due to nonparticipation and loss to follow-up. Furthermore, this ensures that the study results are reliable and generalizable. However, underreporting of traffic-related accidents may occur, which will limit estimation

Coffee consumption and incidence of colorectal cancer in two prospective cohort studies of Swedish women and men.

Science.gov (United States)

Larsson, Susanna C; Bergkvist, Leif; Giovannucci, Edward; Wolk, Alicja

2006-04-01

Investigators have reported an inverse association between coffee consumption and risk of colorectal cancer in several case-control studies, but prospective studies, most of them involving small numbers of cases, have not supported such a relation. In this analysis, the authors prospectively examined the association of coffee consumption with colorectal cancer risk among participants from two population-based cohort studies: 61,433 women in the Swedish Mammography Cohort and 45,306 men in the Cohort of Swedish Men. Information about coffee consumption was obtained from food frequency questionnaires in 1987-1990 and 1997 for women and in 1997 for men. The authors used Cox proportional hazards modeling for cohort-specific multivariate analyses, and results were pooled using random-effects models. During 1,240,597 person-years of follow-up, 1,279 incident cases of colorectal cancer were diagnosed. Coffee consumption was not associated with risk of colorectal cancer, colon cancer, or rectal cancer in either women or men. For both cohorts combined, the multivariate rate ratio for colorectal cancer for each additional cup of coffee per day was 1.00 (95% confidence interval: 0.97, 1.04). The associations were not modified by colorectal cancer risk factors. The findings from these two large prospective cohort studies do not support the hypothesis that coffee consumption lowers the risk of colorectal cancer.

Maternal use of fertility drugs and risk of cancer in children--a nationwide population-based cohort study in Denmark

DEFF Research Database (Denmark)

Hargreave, Marie; Jensen, Allan; Nielsen, Thor Schütt Svane

2015-01-01

Large population-based studies are needed to examine the effect of maternal use of fertility drugs on the risk of cancer in children, while taking into account the effect of the underlying infertility. A cohort of 123,322 children born in Denmark between 1964 and 2006 to 68,255 women who had been...... evaluated for infertility was established. We used a case-cohort design and calculated hazard ratios (HRs) for cancer in childhood (0-19 years) and in young adulthood (20-29 years) associated with maternal use of six groups of fertility drugs (clomiphene, gonadotropins [i.e., human menopausal gonadotropins...... and follicle-stimulating hormone], gonadotropin-releasing hormone analogs, human chorionic gonadotropins, progesterone and other fertility drugs). We found no statistically significant association between maternal use of fertility drugs and risk for overall cancer in childhood or young adulthood. However...

Statin adherence and the risk of Parkinson's disease: A population-based cohort study.

Science.gov (United States)

Rozani, Violetta; Giladi, Nir; El-Ad, Baruch; Gurevich, Tanya; Tsamir, Judith; Hemo, Beatriz; Peretz, Chava

2017-01-01

While experimental data provided some compelling evidence on the benefits of statins on dopaminergic neurons, observational studies reported conflicting results regarding the potential of statins to effect the risk of Parkinson's disease (PD). To evaluate the association between changes in statin adherence over time and PD risk. A population-based cohort of new statin users (ages 40-79, years 1999-2012) was derived from a large Israeli healthcare services organization. Data included history of statin purchases and low density lipoprotein cholesterol (LDL-C) levels. Personal statin adherence was measured annually by the proportion of days covered (PDC). PD was detected employing a drug-tracer approach. Stratified (by sex, LDL-C levels at baseline and age) Cox proportional hazards models with time-dependent covariates were used to compute adjusted Hazard Ratio (HR) with 95%CI. The cohort included 232,877 individuals, 49.3% men. Mean age at first statin purchase was 56.5 (±9.8) years for men and 58.7 (±9.2) years for women. PDC distribution for the whole follow up period differed between men and women: medians 58.3% and 54.1% respectively. During a mean follow up of 7.6 (±3.4) years, 2,550 (1.1%) PD cases were identified. In a 1-year lagged analysis, we found no association between annual statin adherence and PD risk in all age-groups regardless of statin type and potency. Age-pooled HR (95%CI) for men and women with LDL-C levels at baseline ≤160mg/dL were: 0.99 (0.99-1.01), 1.01 (1.00-1.02); and for men and women with LDL-C >160mg/dL levels: 0.99 (0.98-1.01), 0.97 (0.98-1.01). Our findings suggest that statin adherence over time does not affect PD risk. Future studies should use large-scale cohorts and refining assessments of long-term profiles in statin adherence.

Use of fertility drugs and risk of ovarian cancer: Danish population based cohort study

OpenAIRE

Jensen, Allan; Sharif, Heidi; Frederiksen, Kirsten; Kj?r, Susanne Kr?ger

2009-01-01

Objective To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women. Design Population based cohort study. Setting Danish hospitals and private fertility clinics. Participants 54?362 women with infertility problems referred to all Danish fertility clinics during 1963-98. The median age at first evaluation of infertility was 30 years (range 16-55 years), and the median age at the end of follow-up was 47 (range 18-81) years. In...

A Population-Based Cohort Study on Peripheral Arterial Disease in Patients with Schizophrenia.

Directory of Open Access Journals (Sweden)

Wen-Yu Hsu

Full Text Available Peripheral arterial disease (PAD is considered the leading cause of atherosclerotic cardiovascular morbidity. Several risk factors of PAD have been observed in patients with schizophrenia. Therefore, we hypothesize that the incidence of PAD is higher in the schizophrenia population than in the general population.The patients in this population-based cohort study were selected from the Taiwanese National Health Insurance Research Database on the basis of the claims data from 2000 to 2011. We compared the incidence of PAD between schizophrenia and nonschizophrenia cohorts. Cox proportional hazard regression models were employed for analyzing the risk of PAD after adjustment for sex, age, and comorbidities.The adjusted hazard ratio (HR for PAD in the schizophrenia cohort was 1.26-fold higher than that in the nonschizophrenia cohort. Furthermore, patients with schizophrenia using atypical antipsychotics exhibited a high adjusted HR for PAD.Compared with the general population, the risk of PAD is higher among patients with schizophrenia. Early diagnosis and intervention can mitigate complications resulting from cardiovascular diseases and lower mortality.

[Establishment of Primary Adult MDS Nested Case-Control Study Cohort and Study of Risk Factors Associated with MDS Evolution to Leukemia].

Science.gov (United States)

Ma, Yan; Chen, Bo-Bin; Wang, Xiao-Qin; Xu, Xiao-Ping; Lin, Guo-Wei

2015-12-01

To establish a nested case-control study cohort in myelodysplastic syndrome (MDS) patients and investigate the clinical characteristics, WHO subtype and risk factors associated with MDS evolution to leukemia of this cohort. All patients, ≥18 years of age, provided by 24 Shanghai hospitals with initial clinical findings consistent with a hematopoietic abnormality between June 2003 and April 2007, were the candidates for inclusion in this study. The blood and bone marrow samples of every patient should be provided at baseline. Diagnosis was made by incorporating morphologic, immunophenotypic, cytogenetic and molecular features according to WHO classification criteria. Cytogenetic analysis was performed using conventional G-banding karyotyping and fluorescence in situ hybridization (FISH) techniques. Cumulative risk of evolution was estimated by Kaplan-Meier method. Prognostic factors were evaluated by univariate Log-rank method and multivariate Cox proportional hazard models. A total of 435 patients were diagnosed as MDS. The median age of MDS onset was 58(18-90) years, with 248 male patients and 187 female patients (male: female 1.33: 1). The percentage of cases with refractory cytopenia with multilineage dysplasia (RCMD) was the highest (65.5%), while that of refraetory anemia (RA) (2.3%), refractory anenia with ring sideroblast (RARS) (1.1%) and 5q-syndrome (0.5%) was lower. Trisomy 8 (+8) was the most common chromosome abnormalities (71 cases, 12.7%). The mean follow-up time was 20.3 (4.2-57.1) months. Cases were patients with evolution by the end of follow-up, while controls were patients without evolution by that time. Case group included 41 patients and control group included 342 patients. Univariate analysis showed that the age, sex, WHO subtype, WBC count, absolute neutrophil count (ANC), IPSS cytogenetic subgroup, IPSS group and bone marrow blast percentage were significant risk factors for leukemia-free survival (LFS). Multivariate analysis of COX model

A community-based prospective cohort study of dengue viral infection in Malaysia: the study protocol.

Science.gov (United States)

Jahan, Nowrozy Kamar; Ahmad, Mohtar Pungut; Dhanoa, Amreeta; Meng, Cheong Yuet; Ming, Lau Wee; Reidpath, Daniel D; Allotey, Pascale; Zaini, Anuar; Phipps, Maude Elvira; Fatt, Quek Kia; Rabu, Aman Bin; Sirajudeen, Rowther; Fatan, Ahmad AbdulBasitz Ahmad; Ghafar, Faidzal Adlee; Ahmad, Hamdan Bin; Othman, Iekhsan; SyedHassan, Sharifah

2016-08-11

Globally, dengue infections constitute a significant public health burden. In recent decades, Malaysia has become a dengue hyper-endemic country with the co-circulation of the four dengue virus serotypes. The cyclical dominance of sub-types contributes to a pattern of major outbreaks. The consequences can be observed in the rising incidence of reported dengue cases and dengue related deaths. Understanding the complex interaction of the dengue virus, its human hosts and the mosquito vectors at the community level may help develop strategies for addressing the problem. A prospective cohort study will be conducted in Segamat district of Johor State in Peninsular Malaysia. Researchers received approval from the Malaysian Medical Research Ethics Committee and Monash University Human Research Ethics Committee. The study will be conducted at a Malaysian based health and demographic surveillance site over a 1 year period in three different settings (urban, semi-urban and rural). The study will recruit healthy adults (male and female) aged 18 years and over, from three ethnic groups (Malay, Chinese and Indian). The sample size calculated using the Fleiss method with continuity correction is 333. Sero-surveillance of participants will be undertaken to identify asymptomatic, otherwise healthy cases; cases with dengue fever who are managed as out-patients; and cases with dengue fever admitted to a hospital. A genetic analysis of the participants will be undertaken to determine whether there is a relationship between genetic predisposition and disease severity. A detailed medical history, past history of dengue infection, vaccination history against other flaviviruses such as Japanese encephalitis and Yellow fever, and the family history of dengue infection will also be collected. In addition, a mosquito surveillance will be carried out simultaneously in recruitment areas to determine the molecular taxonomy of circulating vectors. The research findings will estimate the burden

Vegetarianism, low meat consumption and the risk of colorectal cancer in a population based cohort study

Science.gov (United States)

Gilsing, Anne M. J.; Schouten, Leo J.; Goldbohm, R. Alexandra; Dagnelie, Pieter C.; van den Brandt, Piet A.; Weijenberg, Matty P.

2015-01-01

To study how a vegetarian or low meat diet influences the risk of colorectal cancer compared to a high meat diet, and to assess the explanatory role of factors associated with these diets. In the Netherlands Cohort Study – Meat Investigation Cohort (NLCS-MIC) (cohort of 10,210 individuals including 1040 self-defined vegetarians), subjects completed a baseline questionnaire in 1986, based on which they were classified into vegetarians (n = 635), pescetarians (n = 360), 1 day/week- (n = 1259), 2–5 day/week- (n = 2703), and 6-7 day/week meat consumers (n = 5253). After 20.3 years of follow-up, 437 colorectal cancer cases (307 colon, 92 rectal) were available. A non-significantly decreased risk of CRC for vegetarians, pescetarians, and 1 day/week compared to 6-7 day/week meat consumers was observed (age/sex adjusted Hazard Ratios (HR): 0.73(0.47–1.13), 0.80(0.47–1.39), and 0.72(0.52–1.00), respectively). Most of the differences in HR between these groups could be explained by intake of dietary fiber and soy products. Other (non-)dietary factors characteristic for a vegetarian or low meat diet had negligible individual effects, but attenuated the HRs towards the null when combined. Vegetarians, pescetarians, and 1 day/week meat eaters showed a non-significantly decreased risk of colorectal cancer compared to 6-7 day/week meat consumers, mainly due to differences in dietary pattern other than meat intake. PMID:26316135

Chronic comorbidities in children with type 1 diabetes : a population-based cohort study

NARCIS (Netherlands)

Fazelifarsani, Soulmaz; Souverein, Patrick C|info:eu-repo/dai/nl/243074948; van der Vorst, Marja M J; Knibbe, Catherijne A J; de Boer, Anthonius|info:eu-repo/dai/nl/075097346; Mantel-Teeuwisse, Aukje K|info:eu-repo/dai/nl/266775098

OBJECTIVE: To determine the incidence of chronic comorbidities among children with type 1 diabetes (T1D) and to compare incidences with a group of children without diabetes. DESIGN: Population-based cohort study. SETTING: Dutch PHARMO database (1998-2010). PATIENTS: All patients (<19 years old) with

Testicular cancer risk and maternal parity: a population-based cohort study.

Science.gov (United States)

Westergaard, T; Andersen, P K; Pedersen, J B; Frisch, M; Olsen, J H; Melbye, M

1998-04-01

The aim was to study, in a population-based cohort design, whether first-born sons run a higher risk of testicular cancer than later born sons; to investigate whether this difference in risk was affected by birth cohort, age of the son, maternal age, interval to previous delivery and other reproductive factors; and, finally, to evaluate to what extent changes in women's parity over time might explain the increasing incidence of testicular cancer. By using data from the Civil Registration System, a database was established of all women born in Denmark since 1935 and all their children alive in 1968 or born later. Sons with testicular cancer were identified in the Danish Cancer Registry. Among 1015994 sons followed for 15981 967 person-years, 626 developed testicular cancer (443 non-seminomas, 183 seminomas). Later born sons had a decreased risk of testicular cancer (RR = 0.80, 95% CI = 0.67-0.95) compared with first-born sons. The RR was 0.79 (95% CI = 0.64-0.98) for non-seminomas and 0.81 (95% CI = 0.58-1.13) for seminomas. There was no association between testicular cancer risk and overall parity of the mother, maternal or paternal age at the birth of the son, or maternal age at first birth. The decreased risk of testicular cancer among later born sons was not modified by age, birth cohort, interval to the previous birth, sex of the first-born child, or maternal age at birth of the son or at first birth. The increased proportion of first-borns from birth cohort 1946 to birth cohort 1969 only explained around 3% of an approximated two-fold increase in incidence between the cohorts. Our data document a distinctly higher risk of testicular cancer in first-born compared with later born sons and suggest that the most likely explanation should be sought among exposures in utero. The increase in the proportion of first-borns in the population has only contributed marginally to the increase in testicular cancer incidence.

What's in a Name? The Incorrect Use of Case Series as a Study Design Label in Studies Involving Dogs and Cats.

Science.gov (United States)

Sargeant, J M; O'Connor, A M; Cullen, J N; Makielski, K M; Jones-Bitton, A

2017-07-01

Study design labels are used to identify relevant literature to address specific clinical and research questions and to aid in evaluating the evidentiary value of research. Evidence from the human healthcare literature indicates that the label "case series" may be used inconsistently and inappropriately. Our primary objective was to determine the proportion of studies in the canine and feline veterinary literature labeled as case series that actually corresponded to descriptive cohort studies, population-based cohort studies, or other study designs. Our secondary objective was to identify the proportion of case series in which potentially inappropriate inferential statements were made. Descriptive evaluation of published literature. One-hundred published studies (from 19 journals) labeled as case series. Studies were identified by a structured literature search, with random selection of 100 studies from the relevant citations. Two reviewers independently characterized each study, with disagreements resolved by consensus. Of the 100 studies, 16 were case series. The remaining studies were descriptive cohort studies (35), population-based cohort studies (36), or other observational or experimental study designs (13). Almost half (48.8%) of the case series or descriptive cohort studies, with no control group and no formal statistical analysis, included inferential statements about the efficacy of treatment or statistical significance of potential risk factors. Authors, peer-reviewers, and editors should carefully consider the design elements of a study to accurately identify and label the study design. Doing so will facilitate an understanding of the evidentiary value of the results. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

[Application of cohort study in cancer prevention and control].

Science.gov (United States)

Dai, Min; Bai, Yana; Pu, Hongquan; Cheng, Ning; Li, Haiyan; He, Jie

2016-03-01

Cancer control is a long-term work. Cancer research and intervention really need the support of cohort study. In the recent years, more and more cohort studies on cancer control were conducted in China along with the increased ability of scientific research in China. Since 2010, Cancer Hospital, Chinese Academy of Medical Sciences, collaborated with Lanzhou University and the Worker' s Hospital of Jinchuan Group Company Limited, have carried out a large-scale cohort study on cancer, which covered a population of more than 50 000 called " Jinchang cohort". Since 2012, a National Key Public Health Project, "cancer screening in urban China" , has been conducted in Jinchang, which strengthened the Jinchang cohort study. Based on the Jinchang cohort study, historical cohort study, cross-sectional study and prospective cohort study have been conducted, which would provide a lot of evidence for the cancer control in China.

Comparison of 2 resident learning tools-interactive screen-based simulated case scenarios versus problem-based learning discussions: a prospective quasi-crossover cohort study.

Science.gov (United States)

Rajan, Shobana; Khanna, Ashish; Argalious, Maged; Kimatian, Stephen J; Mascha, Edward J; Makarova, Natalya; Nada, Eman M; Elsharkawy, Hesham; Firoozbakhsh, Farhad; Avitsian, Rafi

2016-02-01

Simulation-based learning is emerging as an alternative educational tool in this era of a relative shortfall of teaching anesthesiologists. The objective of the study is to assess whether screen-based (interactive computer simulated) case scenarios are more effective than problem-based learning discussions (PBLDs) in improving test scores 4 and 8 weeks after these interventions in anesthesia residents during their first neuroanesthesia rotation. Prospective, nonblinded quasi-crossover study. Cleveland Clinic. Anesthesiology residents. Two case scenarios were delivered from the Anesoft software as screen-based sessions, and parallel scripts were developed for 2 PBLDs. Each resident underwent both types of training sessions, starting with the PBLD session, and the 2 cases were alternated each month (ie, in 1 month, the screen-based intervention used case 1 and the PBLD used case 2, and vice versa for the next month). Test scores before the rotation (baseline), immediately after the rotation (4 weeks after the start of the rotation), and 8 weeks after the start of rotation were collected on each topic from each resident. The effect of training method on improvement in test scores was assessed using a linear mixed-effects model. Compared to the departmental standard of PBLD, the simulation method did not improve either the 4- or 8-week mean test scores (P = .41 and P = .40 for training method effect on 4- and 8-week scores, respectively). Resident satisfaction with the simulation module on a 5-point Likert scale showed subjective evidence of a positive impact on resident education. Screen-based simulators were not more effective than PBLD for education during the neuroanesthesia rotation in anesthesia residency. Copyright © 2016 Elsevier Inc. All rights reserved.

Is outdoor work associated with elevated rates of cerebrovascular disease mortality? : a cohort study based on iron-ore mining

OpenAIRE

Björ, Ove; Jonsson, Håkan; Damber, Lena; Burström, Lage; Nilsson, Tohr

2016-01-01

BACKGROUND: A cohort study that examined iron ore mining found negative associations between cumulative working time employed underground and several outcomes, including mortality of cerebrovascular diseases. In this cohort study, and using the same group of miners, we examined whether work in an outdoor environment could explain elevated cerebrovascular disease rates. METHODS: This study was based on a Swedish iron ore mining cohort consisting of 13,000 workers. Poisson regression models wer...

Method for mapping population-based case-control studies: an application using generalized additive models

Directory of Open Access Journals (Sweden)

Aschengrau Ann

2006-06-01

Full Text Available Abstract Background Mapping spatial distributions of disease occurrence and risk can serve as a useful tool for identifying exposures of public health concern. Disease registry data are often mapped by town or county of diagnosis and contain limited data on covariates. These maps often possess poor spatial resolution, the potential for spatial confounding, and the inability to consider latency. Population-based case-control studies can provide detailed information on residential history and covariates. Results Generalized additive models (GAMs provide a useful framework for mapping point-based epidemiologic data. Smoothing on location while controlling for covariates produces adjusted maps. We generate maps of odds ratios using the entire study area as a reference. We smooth using a locally weighted regression smoother (loess, a method that combines the advantages of nearest neighbor and kernel methods. We choose an optimal degree of smoothing by minimizing Akaike's Information Criterion. We use a deviance-based test to assess the overall importance of location in the model and pointwise permutation tests to locate regions of significantly increased or decreased risk. The method is illustrated with synthetic data and data from a population-based case-control study, using S-Plus and ArcView software. Conclusion Our goal is to develop practical methods for mapping population-based case-control and cohort studies. The method described here performs well for our synthetic data, reproducing important features of the data and adequately controlling the covariate. When applied to the population-based case-control data set, the method suggests spatial confounding and identifies statistically significant areas of increased and decreased odds ratios.

ABO and RhD blood groups and gestational hypertensive disorders: a population-based cohort study.

Science.gov (United States)

Lee, B K; Zhang, Z; Wikman, A; Lindqvist, P G; Reilly, M

2012-09-01

To examine the association between ABO and RhD blood groups and gestational hypertensive disorders in a large population-based cohort. Cohort study. Risks of gestational hypertensive disorders, pre-eclampsia, and severe pre-eclampsia, estimated by odds ratios for maternal ABO blood group and RhD status. National health registers of Sweden. All singleton deliveries in Sweden born to first-time mothers during the period 1987-2002 [total n = 641 926; any gestational hypertensive disorders, n = 39 011 (6.1%); pre-eclampsia cases, n = 29 337 (4.6%); severe pre-eclampsia cases, n = 8477 (1.3%)]. Using blood group O as a reference, odds ratios of gestational hypertensive disorders, pre-eclampsia, and severe pre-eclampsia were obtained from logistic regression models adjusted for potential confounding factors. Gestational hypertensive disorders, pre-eclampsia, and severe pre-eclampsia. Compared with blood group O, all non-O blood groups had modest but statistically significantly higher odds of pre-eclampsia. Blood group AB had the highest risk for pre-eclampsia (OR = 1.10, 95% CI 1.04-1.16) and severe pre-eclampsia (OR = 1.18, 95% CI 1.07-1.30). RhD-positive mothers had a small increased risk for pre-eclampsia (OR = 1.07, 95% CI 1.03-1.10). In the largest study on this topic to date, women with AB blood group have the highest risks of gestational hypertensive disorders, pre-eclampsia, and severe pre-eclampsia, whereas women with O blood group have the lowest risks of developing these disorders. Although the magnitude of increased risk is small, this finding may help improve our understanding of the etiology of pre-eclampsia. © 2012 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2012 RCOG.

Accuracy of clinical diagnosis versus the World Health Organization case definition in the Amoy Garden SARS cohort.

Science.gov (United States)

Wong, W N; Sek, Antonio C H; Lau, Rick F L; Li, K M; Leung, Joe K S; Tse, M L; Ng, Andy H W; Stenstrom, Robert

2003-11-01

To compare the diagnostic accuracy of emergency department (ED) physicians with the World Health Organization (WHO) case definition in a large community-based SARS (severe acute respiratory syndrome) cohort. This was a cohort study of all patients from Hong Kong's Amoy Garden complex who presented to an ED SARS screening clinic during a 2-month outbreak. Clinical findings and WHO case definition criteria were recorded, along with ED diagnoses. Final diagnoses were established independently based on relevant diagnostic tests performed after the ED visit. Emergency physician diagnostic accuracy was compared with that of the WHO SARS case definition. Sensitivity, specificity, predictive values and likelihood ratios were calculated using standard formulae. During the study period, 818 patients presented with SARS-like symptoms, including 205 confirmed SARS, 35 undetermined SARS and 578 non-SARS. Sensitivity, specificity and accuracy were 91%, 96% and 94% for ED clinical diagnosis, versus 42%, 86% and 75% for the WHO case definition. Positive likelihood ratios (LR+) were 21.1 for physician judgement and 3.1 for the WHO criteria. Negative likelihood ratios (LR-) were 0.10 for physician judgement and 0.67 for the WHO criteria, indicating that clinician judgement was a much more powerful predictor than the WHO criteria. Physician clinical judgement was more accurate than the WHO case definition. Reliance on the WHO case definition as a SARS screening tool may lead to an unacceptable rate of misdiagnosis. The SARS case definition must be revised if it is to be used as a screening tool in emergency departments and primary care settings.

Association of Neovascular Glaucoma with Risk of Stroke: A Population-Based Cohort Study

Directory of Open Access Journals (Sweden)

Cheng-Wen Su

2017-01-01

Full Text Available Neovascular glaucoma (NVG, caused by ocular ischemia, is a serious ocular disease complicated by intractably increased intraocular pressure. Cerebrovascular accidents are classified into ischemic and hemorrhagic stroke. Based on the similar pathogenic mechanisms of NVG and ischemic stroke, we investigated the relationship between NVG and stroke by using a nationally representative sample. This study included 416 NVG patients and 4160 controls. Medical comorbidities were also evaluated. The cumulative incidence of ischemic stroke was 15.6% higher in the NVG cohort than in the control cohort (p<0.001; the incidence density rates of stroke were 3.80 and 1.19 per 10,000 person-years in the NVG and control cohorts, respectively. According to the multivariable Cox regression results, the estimated adjusted hazard ratio (aHR of stroke was 2.07 (95% confidence interval (CI = 1.41–3.02 for the NVG cohort. Furthermore, the NVG cohort was 2.24-fold more likely to develop ischemic stroke (95% CI = 1.51–3.32. The risk of ischemic stroke was higher in patients with hypertension (aHR = 2.09, 95% CI = 1.55–2.82 and in patients with diabetic retinopathy (aHR = 1.69, 95% CI = 1.05–2.72. Notably, patients with NVG have a higher risk of ischemic stroke, but not hemorrhagic stroke.

Association between diverticular disease and Ehlers-Danlos syndrome: a 13-year nationwide population-based cohort study.

Science.gov (United States)

Leganger, Julie; Søborg, Marie-Louise Kulas; Mortensen, Laura Quitzau; Gregersen, Rasmus; Rosenberg, Jacob; Burcharth, Jakob

2016-12-01

The aim of this study was to examine occurrence and consequences of diverticular disease in patients with Ehlers-Danlos syndrome (EDS) compared with a matched cohort. This nationwide population-based cohort study was conducted using data from medical registers in Denmark from year 2000 to 2012. The EDS cohort was identified using the specific diagnosis code for EDS and was randomly matched in a ratio of 1:20 by sex and date of birth (±1 year) with persons from the Danish general population. The occurrence of diverticular disease and the clinical characteristics of the initial diverticular event were compared between the EDS cohort and the comparison cohort. The first admission with diverticulitis was identified, and severity of diverticulitis, treatment, colonoscopies, length of stay, and 30-day mortality were investigated. We identified 1336 patients with EDS and matched a control cohort of 26,720 patients. The occurrence of diverticular disease in the EDS cohort (2.0 %) and the comparison cohort (0.68 %) differed significantly (p < 0.001). At the first diverticular event, the majority of patients were women (85 % for EDS and 87 % for the comparison cohort). Mean age, localization, and type of contact did not differ significantly. Admission with diverticulitis (1.0 % for EDS and 0.34 % for the comparison cohort) differed significantly (p < 0.001). We found no significant difference in severity of diverticulitis, treatment, length of stay, or 30-day mortality between the EDS and the comparison cohorts. Patients with EDS had an increased occurrence of overall diverticular events and admissions with diverticulitis compared with the general population.

Association of stress and depression with chronic facial pain: A case-control study based on the Northern Finland 1966 Birth Cohort.

Science.gov (United States)

Nevalainen, Netta; Lähdesmäki, Raija; Mäki, Pirjo; Ek, Ellen; Taanila, Anja; Pesonen, Paula; Sipilä, Kirsi

2017-05-01

The aim was to study the association between stress level and chronic facial pain, while controlling for the effect of depression on this association, during a three-year follow-up in a general population-based birth cohort. In the general population-based Northern Finland 1966 Birth Cohort, information about stress level, depression and facial pain were collected using questionnaires at the age of 31 years. Stress level was measured using the Work Ability Index. Depression was assessed using the 13-item depression subscale in the Hopkins Symptom Checklist-25. Three years later, a subsample of 52 subjects (42 women) with chronic facial pain and 52 pain-free controls (42 women) was formed. Of the subjects having high stress level at baseline, 73.3% had chronic facial pain, and 26.7% were pain-free three years later. The univariate logistic regression analysis showed that high stress level at 31 years increased the risk for chronic facial pain (crude OR 6.1, 95%, CI 1.3-28.7) three years later. When including depression in a multivariate model, depression associated statistically significantly with chronic facial pain (adjusted OR 2.5, 95%, CI 1.0-5.8), whereas stress level did not (adjusted OR 2.3, 95%, CI 0.6-8.4). High stress level is connected with increased risk for chronic facial pain. This association seems to mediate through depression.

Use of fertility drugs and risk of ovarian cancer: Danish Population Based Cohort Study

DEFF Research Database (Denmark)

Jensen, Allan; Sharif, Heidi; Frederiksen, Kirsten

2009-01-01

OBJECTIVE: To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women. DESIGN: Population based cohort study. SETTING: Danish hospitals and private fertility clinics. PARTICIPANTS: 54,362 women with infertility problems referred...... confounding factors. RESULTS: Analyses within cohort showed no overall increased risk of ovarian cancer after any use of gonadotrophins (rate ratio 0.83, 95% confidence interval 0.50 to 1.37), clomifene (1.14, 0.79 to 1.64), human chorionic gonadotrophin (0.89, 0.62 to 1.29), or gonadotrophin releasing...... hormone (0.80, 0.42 to 1.51). Furthermore, no associations were found between all four groups of fertility drugs and number of cycles of use, length of follow-up, or parity. CONCLUSION: No convincing association was found between use of fertility drugs and risk of ovarian cancer....

Motives for participating in a web-based nutrition cohort according to sociodemographic, lifestyle, and health characteristics: the NutriNet-Santé cohort study.

Science.gov (United States)

Méjean, Caroline; Szabo de Edelenyi, Fabien; Touvier, Mathilde; Kesse-Guyot, Emmanuelle; Julia, Chantal; Andreeva, Valentina A; Hercberg, Serge

2014-08-07

In traditional epidemiological studies, participants are likely motivated by perceived benefits, feelings of accomplishment, and belonging. No study has explored motives for participation in a Web-based cohort and the associated participant characteristics, although such information is useful for enhancing recruitment and improving cohort retention. We aimed to evaluate the relationships between motives for participation and sociodemographic, health, and lifestyle characteristics of participants in the NutriNet-Santé Web-based cohort, designed to identify nutritional risk or protective factors for chronic diseases. The motives for participation were assessed using a specifically developed questionnaire administered approximately 2 years after baseline. A total of 6352 completed the motives questionnaire (43.34%, 6352/15,000 randomly invited cohort participants). We studied the associations between motives (dependent variables) and individual characteristics with multivariate multinomial logistic regression models providing odds ratios and 95% confidence intervals. In total, 46.45% (2951/6352) of participants reported that they would not have enrolled if the study had not been conducted on the Internet, whereas 28.75% (1826/6352) were not sure. Men (OR 1.21, 95% CI 1.04-1.42), individuals aged 26-35 years (OR 1.51, 95% CI 1.20-1.91), and obese participants (OR 1.30, 95% CI 1.02-1.65) were more inclined to be motivated by the Internet aspect. Compared with younger adults and managerial staff, individuals >55 years (OR 0.60, 95% CI 0.48-0.45) and employees/manual workers were less likely motivated by the Internet aspect (OR 0.77, 95% CI 0.63-0.92). Regarding reasons for participation, 61.37% (3898/6352) reported participating to help advance public health research on chronic disease prevention; 22.24% (1413/6352) to help advance nutrition-focused research; 6.89% (438/6352) in response to the call from the media, after being encouraged by a close friend/associate, or

Risk of Suicide Attempt in Poststroke Patients: A Population-Based Cohort Study.

Science.gov (United States)

Harnod, Tomor; Lin, Cheng-Li; Kao, Chia-Hung

2018-01-10

This nationwide population-based cohort study evaluated the risk of and risk factors for suicide attempt in poststroke patients in Taiwan. The poststroke and nonstroke cohorts consisted of 713 690 patients and 1 426 009 controls, respectively. Adults (aged >18 years) who received new stroke diagnoses according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM ; codes 430-438) between 2000 and 2011 were included in the poststroke cohort. We calculated the adjusted hazard ratio for suicide attempt ( ICD-9-CM codes E950-E959) after adjustment for age, sex, monthly income, urbanization level, occupation category, and various comorbidities. Kaplan-Meier analysis was used to measure the cumulative incidence of suicide attempt, and the Fine and Gray method was used as a competing event when estimating death subhazard ratios and 95% confidence intervals between groups. The cumulative incidence of suicide attempt was higher in the poststroke cohort, and the adjusted hazard ratio of suicide attempt was 2.20 (95% confidence interval, 2.04-2.37) compared with that of the controls. The leading risk factors for poststroke suicide attempt were earning low monthly income (US dollars), living in less urbanized regions, doing manual labor, and having a stroke before age 50 years. The attempted suicide risk did not differ significantly between male and female patients in this study. These results convey crucial information to clinicians and governments for preventing suicide attempt in poststroke patients in Taiwan and other Asian countries. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Prospect-EPIC Utrecht: study design and characteristics of the cohort population. European Prospective Investigation into Cancer and Nutrition.

Science.gov (United States)

Boker, L K; van Noord, P A; van der Schouw, Y T; Koot, N V; Bueno de Mesquita, H B; Riboli, E; Grobbee, D E; Peeters, P H

2001-01-01

The European Prospective Investigation into Cancer and Nutrition (EPIC), which has been established in order to investigate the relations between nutrition and cancer, was initiated in 1990 and involves 10 European countries with heterogeneous dietary patterns and differing cancer incidence rates. This manuscript presents the design, recruitment and baseline characteristics of the Prospect-EPIC cohort co-ordinated in Utrecht, The Netherlands. The cohort is based on volunteers recruited among women participating in a regional breast cancer screening program. It comprises of 17,357 subjects aged 50-69 years at enrolment from Utrecht and vicinity, who have consented to participate in the study and its follow-up. Each participant filled out a general questionnaire and a food frequency questionnaire. Participants were also physically examined and have donated a blood sample. Participation rate was 34.5%. Blood samples were donated by most participants (97.5%) and detailed informed consents were obtained from 87.4% of participants. Mean age at enrolment was 57 years. Anthropometric, lifestyle and morbidity characteristics of the cohort population did not differ largely from those of similar study populations in The Netherlands. Based on the Prospect-EPIC population, we intend to conduct prospective total cohort, nested case-control or case-cohort studies, in order to investigate relations between consumption of certain food groups or nutrients and chronic diseases, including hormone dependant cancers such as breast, colon, endometrial and ovary cancers.

Study protocol: the JEU cohort study--transversal multiaxial evaluation and 5-year follow-up of a cohort of French gamblers.

Science.gov (United States)

Challet-Bouju, Gaëlle; Hardouin, Jean-Benoit; Vénisse, Jean-Luc; Romo, Lucia; Valleur, Marc; Magalon, David; Fatséas, Mélina; Chéreau-Boudet, Isabelle; Gorsane, Mohamed-Ali; Grall-Bronnec, Marie

2014-08-20

There is abundant literature on how to distinguish problem gambling (PG) from social gambling, but there are very few studies of the long-term evolution of gambling practice. As a consequence, the correlates of key state changes in the gambling trajectory are still unknown. The objective of the JEU cohort study is to identify the determinants of key state changes in the gambling practice, such as the emergence of a gambling problem, natural recovery from a gambling problem, resolution of a gambling problem with intermediate care intervention, relapses or care recourse. The present study was designed to overcome the limitations of previous cohort study on PG. Indeed, this longitudinal case-control cohort is the first which plans to recruit enough participants from different initial gambling severity levels to observe these rare changes. In particular, we plan to recruit three groups of gamblers: non-problem gamblers, problem gamblers without treatment and problem gamblers seeking treatment.Recruitment takes place in various gambling places, through the press and in care centers. Cohort participants are gamblers of both sexes who reported gambling on at least one occasion in the previous year and who were aged between 18 and 65. They were assessed through a structured clinical interview and self-assessment questionnaires at baseline and then once a year for five years. Data collection comprises sociodemographic characteristics, gambling habits (including gambling trajectory), the PG section of the DSM-IV, the South Oaks Gambling Screen, the Gambling Attitudes and Beliefs Survey - 23, the Mini International Neuropsychiatric Interview, the Wender-Utah Rating Scale-Child, the Adult ADHD Self-report Scale, somatic comorbidities (especially current treatment and Parkinson disease) and the Temperament and Character Inventory - 125. The JEU cohort study is the first study which proposes to identify the predictive factors of key state changes in gambling practice. This is

Selective Screening Strategies for Gestational Diabetes: A Prospective Cohort Observational Study

Directory of Open Access Journals (Sweden)

Sumaiya Adam

2017-01-01

Full Text Available Aim. We aimed to develop a prediction model for the diagnosis of gestational diabetes and to evaluate the performance of published prediction tools on our population. Methods. We conducted a cohort study on nondiabetic women  10%, 25.6% of cases were detected without the HbA1c, and 25.8% of cases would have been detected with the HbA1c. The 9 published scoring systems performed poorly. Conclusion. We propose a nomogram-based score that can be used at first antenatal visit to identify women at high risk of GDM.

Autism and Convictions for Violent Crimes: Population-Based Cohort Study in Sweden.

Science.gov (United States)

Heeramun, Ragini; Magnusson, Cecilia; Gumpert, Clara Hellner; Granath, Sven; Lundberg, Michael; Dalman, Christina; Rai, Dheeraj

2017-06-01

Recent systematic reviews have highlighted that the relationship between autism and violent offending is still unclear, but some cases have received extensive media scrutiny. We investigated whether autism is associated with convictions for violent crimes, and studied the associated risk and protective factors. We analyzed data from the Stockholm Youth Cohort, a total population-based record-linkage cohort in Stockholm County comprising 295,734 individuals followed up between 15 and 27 years of age. Of these, 5,739 individuals had a recorded autism diagnosis. The main outcome measure was a conviction for violent crimes identified using the Swedish National Crime Register. Individuals with autism, particularly those without intellectual disability, initially appeared to have a higher risk of violent offending (adjusted relative risk = 1.39, 95% CI = 1.23-1.58). However, these associations markedly attenuated after co-occurring attention-deficit/hyperactivity disorder (ADHD) or conduct disorder were taken into account (adjusted relative risk = 0.85, 95% CI = 0.75-0.97). Among individuals with autism, male sex and psychiatric conditions were the strongest predictors of violent criminality, along with parental criminal and psychiatric history and socioeconomic characteristics. There was some evidence that a delayed diagnosis of autism was associated with a greater risk of violent crime. Better school performance and intellectual disability appeared to be protective. An initially observed association between autism and violent crimes at a population level was explained by comorbidity with ADHD and conduct disorder. Better understanding and management of comorbid psychopathology in autism may potentially help preventive action against offending behaviors in people with autism. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

The population-based Occupational and Environmental Health Prospective Cohort Study (AMIGO) in The Netherlands.

Science.gov (United States)

Slottje, Pauline; Yzermans, C Joris; Korevaar, Joke C; Hooiveld, Mariëtte; Vermeulen, Roel C H

2014-11-26

Occupational and environmental exposures remain important modifiable risk factors of public health. Existing cohort studies are often limited by the level of detail of data collected on these factors and health. It is also often assumed that the more healthy group is over-represented in cohort studies, which is of concern for their external validity. In this cohort profile, we describe how we set up the population-based Occupational and Environmental Health Cohort Study (AMIGO) to longitudinally study occupational and environmental determinants of diseases and well-being from a multidisciplinary and life course point of view. Reviewed by the Medical Ethics Research Committee of the University Medical Center Utrecht (protocol 10-268/C). All cohort members participate voluntarily and gave informed consent prior to their inclusion. 14,829 adult cohort members (16% of those invited) consented and filled in the online baseline questionnaire. Determinants include chemical, biological, physical (eg, electromagnetic fields), and psychosocial factors. Priority health outcomes include cancer, neurological, cardiovascular and respiratory diseases and non-specific symptoms. Owing to the recruitment strategy via general practitioners of an established network, we also collect longitudinal data registered in their electronic medical records including symptoms, diagnosis and treatments. Besides the advantage of health outcomes that cannot be easily captured longitudinally by other means, this created a unique opportunity to assess health-related participation bias by comparing general practitioner-registered prevalence rates in the cohort and its source population. We found no indications of such a systematic bias. The major assets of the AMIGO approach are its detailed occupational and environmental determinants in combination with the longitudinal health data registered in general practice besides linkage to cancer and mortality registries and self-reported health. We are now

Statins and Hip Fracture Prevention – A Population Based Cohort Study in Women

Science.gov (United States)

Helin-Salmivaara, Arja; Korhonen, Maarit J.; Lehenkari, Petri; Junnila, Seppo Y. T.; Neuvonen, Pertti J.; Ruokoniemi, Päivi; Huupponen, Risto

2012-01-01

Objective To study the association of long-term statin use and the risk of low-energy hip fractures in middle-aged and elderly women. Design A register-based cohort study. Setting Finland. Participants Women aged 45–75 years initiating statin therapy between 1996 and 2001 with adherence to statins ≥80% during the subsequent five years (n = 40 254), a respective cohort initiating hypertension drugs (n = 41 610), and women randomly selected from the population (n = 62 585). Main Outcome Measures Incidence rate of and hazard ratio (HR) for low-energy hip fracture during the follow-up extending up to 7 years after the 5-year exposure period. Results Altogether 199 low-energy hip fractures occurred during the 135 330 person-years (py) of follow-up in the statin cohort, giving an incidence rate of 1.5 hip fractures per 1000 py. In the hypertension and the population cohorts, the rates were 2.0 per 1000 py (312 fractures per 157 090 py) and 1.0 per 1000 py (212 fractures per 216 329 py), respectively. Adjusting for a propensity score and individual variables strongly predicting the outcome, good adherence to statins for five years was associated with a 29% decreased risk (HR 0.71; 95% CI 0.58–0.86) of a low-energy hip fracture in comparison with adherent use of hypertension drugs. The association was of the same magnitude when comparing the statin users with the population cohort, the HR being 0.69 (0.55–0.87). When women with poor (statins were compared to those with good adherence to hypertension drugs (≥80%) or to the population cohort, the protective effect associated with statin use attenuated with the decreasing level of adherence. Conclusions 5-year exposure to statins is associated with a reduced risk of low-energy hip fracture in women aged 50–80 years without prior hospitalizations for fractures. PMID:23144731

Recurrence risk of low Apgar score among term singletons: a population-based cohort study

NARCIS (Netherlands)

Ensing, Sabine; Schaaf, Jelle M.; Abu-Hanna, Ameen; Mol, Ben W. J.; Ravelli, Anita C. J.

2014-01-01

To examine the risk of recurrence of low Apgar score in a subsequent term singleton pregnancy. Population-based cohort study. The Netherlands. A total of 190,725 women with two subsequent singleton term live births between 1999 and 2007. We calculated the recurrence risk of low Apgar score after

A case-control study of employment status and mortality in a cohort of Australian youth.

Science.gov (United States)

Morrell, S; Taylor, R; Quine, S; Kerr, C; Western, J

1999-08-01

Recent studies have demonstrated a link in young populations between unemployment and ill health. The purpose of this study is to correlate mortality with employment status in two cohorts of young Australian males, aged 17-25 years, from 1984 to 1988. Two youth cohorts consisting of an initially unemployed sample (n = 1424 males) and a population sample (n = 4573 males), were surveyed annually throughout the study period. Those lost to follow-up during the survey period were matched with death registries across Australia. Employment status was determined from weekly diaries and death certificates and was designated as: employed or student; unemployed; not in the work force (excluding students). Conditional logistic regression, using age- and cohort- matched cases (deaths) and controls (alive), was used to estimate the odds ratio (OR) of dying with regard to employment status, taking into account potential confounders such as ethnicity, aboriginality, educational attainment, pre-existing health problems, socio-economic status of parents, and other factors. Twenty three male survey respondents were positively matched to death registry records. Compared to those employed or students (referent group), significantly elevated ORs were found to be associated with neither being in the workforce nor a student for all cause, external cause, and external cause mortality other than suicide. Odds ratios were adjusted for age, survey cohort, ethnicity, pre-existing physical and mental health status, education level, and socio-economic status of parent(s). A statistically significant increasing linear trend in odds ratios of male mortality for most cause groups was found across the employment categories, from those employed or student (lowest ORs), through those unemployed, to those not in the workforce (highest ORs). Suicide was higher, but not statistically significantly, in those unemployed or not in the workforce. Suicide also was associated, though not significantly, with

Do antidepressants increase the risk of mania and bipolar disorder in people with depression? A retrospective electronic case register cohort study

NARCIS (Netherlands)

Patel, Rashmi; Reiss, Peter; Shetty, Hitesh; Broadbent, Matthew; Stewart, Robert; McGuire, Philip; Taylor, Matthew

2015-01-01

Objectives To investigate the association between antidepressant therapy and the later onset of mania/bipolar disorder. Design Retrospective cohort study using an anonymised electronic health record case register. Setting South London and Maudsley National Health Service (NHS) Trust (SLaM), a large

Risk for borderline ovarian tumours after exposure to fertility drugs: results of a population-based cohort study.

Science.gov (United States)

Bjørnholt, Sarah Marie; Kjaer, Susanne Krüger; Nielsen, Thor Schütt Svane; Jensen, Allan

2015-01-01

Do fertility drugs increase the risk for borderline ovarian tumours, overall and according to histological subtype? The use of any fertility drug did not increase the overall risk for borderline ovarian tumours, but an increased risk for serous borderline ovarian tumours was observed after the use of progesterone. Many epidemiological studies have addressed the connection between fertility drugs use and risk for ovarian cancer; most have found no strong association. Fewer studies have assessed the association between use of fertility drugs and risk for borderline ovarian tumours, and the results are inconsistent. A retrospective case-cohort study was designed with data from a cohort of 96 545 Danish women with fertility problems referred to all Danish fertility clinics in the period 1963-2006. All women were followed for first occurrence of a borderline ovarian tumour from the initial date of infertility evaluation until a date of migration, date of death or 31 December 2006, whichever occurred first. The median length of follow-up was 11.3 years. Included in the analyses were 142 women with borderline ovarian tumours (cases) and 1328 randomly selected sub-cohort members identified in the cohort during the follow-up through 2006. Cases were identified by linkage to the Danish Cancer Register and the Danish Register of Pathology by use of personal identification numbers. To obtain information on use of fertility drugs, hospital files and medical records of infertility-associated visits to all Danish fertility clinics were collected and supplemented with information from the Danish IVF register. We used case-cohort techniques to calculate rate ratios (RRs) and corresponding 95% confidence intervals (CIs) for borderline ovarian tumours, overall and according to histological subtype, associated with the use of any fertility drug or five specific groups of fertility drugs: clomiphene citrate, gonadotrophins (human menopausal gonadotrophins and follicle

Exposure to magnetic fields and survival after diagnosis of childhood leukemia: a German cohort study

DEFF Research Database (Denmark)

Svendsen, Anne Louise; Weihkopf, Thomas; Kaatsch, Peter

2007-01-01

Inspired by a recent U.S. study showing poorer survival among children with acute lymphoblastic leukemia (ALL) exposed to magnetic fields above 0.3 microT, we examine this relationship in a German cohort of childhood leukemia cases derived from previous population-based case-control studies...... for prognostic risk group, the hazard for exposures above 0.2 microT increases to HR, 3.0 (95% CI, 0.9-9.8). In conclusion, this study is generally consistent with the previous finding; however, we report the excess risk at field levels lower than those in the U.S. study. In all, the evidence is still based...

The Fender Stratocaster Electric Guitar: A Case Study for both Nontransferable and Transferable Skills Learning in a Generalist Electronic Engineering Cohort

Science.gov (United States)

Joyce, M. J.

2010-01-01

A case-study approach to teaching electronics system design that has been used since 2004 to demonstrate the importance of both nontransferable and transferable design issues to first-year undergraduate students is described. The student cohort of relevance to this work represents a diverse group comprising both students studying for a four-year…

Thyroid cancer incidence among Asian immigrants to Ontario, Canada: A population-based cohort study.

Science.gov (United States)

Shah, Baiju R; Griffiths, Rebecca; Hall, Stephen F

2017-09-01

The highest rates of thyroid cancer are observed in Pacific Island nations as well as Australia and Asian countries bordering the Pacific. The objective of this study was to determine the risk for thyroid cancer among immigrants to Canada from Southeast and East Asia compared with immigrants from other regions and nonimmigrants. This was a population-based, longitudinal cohort study using health care administrative data to examine all residents of Ontario without pre-existing thyroid cancer. Individuals were followed from January 1997 or 5 years after they became eligible for health care coverage in Ontario, whichever came later. Patients were followed until March 2015 for incident-differentiated thyroid cancer, and then for recurrence. The study followed 14,659,733 individuals for a median of 17 years. Thyroid cancer incidence was 43.8 cases per 100,000 person-years among Southeast Asian immigrants, 28.6 cases per 100,000 person-years among East Asian immigrants, 21.5 cases per 100,000 person-years among other immigrants, and 14.5 cases per 100,000 person-years among nonimmigrants. Incidence was highest among immigrants from the Philippines (52.7 cases per 100,000 person-years), South Korea (33.5 cases per 100,000 person-years), and China (30.0 cases per 100,000 person-years). Adjusted hazard ratios for thyroid cancer compared with nonimmigrants were 2.66 (95% confidence interval, 2.48-2.84) for Southeast Asian immigrants, 1.87 (95% confidence interval, 1.75-2.00) for East Asian immigrants, and 1.51 (95% confidence interval, 1.45-1.57) for other immigrants. Immigrants were more likely to have papillary histology and stage I cancer. East Asian immigrants, but not Southeast Asian immigrants, had a lower risk of recurrence (hazard ratio, 0.73 [95% confidence interval, 0.57-0.94] and 1.01 [95% confidence interval, 0.81-1.26], respectively). Immigrants from Southeast and East Asia had markedly higher thyroid cancer incidence than nonimmigrants. At particularly elevated

Placebo cohorts in phase-3 MS treatment trials - predictors for on-trial disease activity 1990-2010 based on a meta-analysis and individual case data.

Directory of Open Access Journals (Sweden)

Jan-Patrick Stellmann

Full Text Available BACKGROUND: Annualized relapse rates (ARR in the placebo cohorts of phase-3 randomized controlled trials (RCT of new treatments for relapsing remitting multiple sclerosis (RRMS have decreased substantially during the last two decades. The causes of these changes are not clear. We consider a better understanding of this phenomenon essential for valuing the effects of new drugs and by designing new trials. OBJECTIVES: To identify predictive factors of on-study ARR in early and recent MS trials. METHODS: ARR, rate of relapse-free patients, trial start dates, baseline demographics, relapse definitions and the use of McDonald criteria were retrieved by literature research of the placebo cohorts from RRMS phase-3 trials. Predictors were estimated by univariate and multivariate regression analyses and random-effects meta-regression. In addition, regression models were calculated by the Sylvia Lawry Centre's (SLC, including individual case data from clinical trials performed until 2000. The most reliable meta-analytic results can be gained from pooled individual case data. In lack of this, random-effects meta-analyses are recommended. RESULTS: Data from 12 published and one unpublished trial show a decrease of ARR from 1988 to 2012 (adjR(2 = 0.807, p<0.0001. Regression models identified McDonald criteria followed by baseline mean age and the pre-study relapse rate as predictors of the ARR. The pooled individual case data (n = 505 confirmed a decrease of ARR over time. The pre-study relapse rate was the best predictor for on-study relapses. Lacking individual case data after implementation of the McDonald criteria excludes a direct comparison concerning McDonald criteria. CONCLUSION: Pre-study relapse rate was the best predictor for on-study relapse rate but failed to explain the decrease of the ARR over time alone. Higher age at baseline and the implementation of McDonald criteria were associated as well with a lowered relapse rate in the random

Sibship structure and risk of infectious mononucleosis: a population-based cohort study.

Science.gov (United States)

Rostgaard, Klaus; Nielsen, Trine Rasmussen; Wohlfahrt, Jan; Ullum, Henrik; Pedersen, Ole; Erikstrup, Christian; Nielsen, Lars Peter; Hjalgrim, Henrik

2014-10-01

Present understanding of increased risk of Epstein-Barr virus (EBV)-related infectious mononucleosis among children of low birth order or small sibships is mainly based on old and indirect evidence. Societal changes and methodological limitations of previous studies call for new data. We used data from the Danish Civil Registration System and the Danish National Hospital Discharge Register to study incidence rates of inpatient hospitalizations for infectious mononucleosis before the age of 20 years in a cohort of 2,543,225 Danes born between 1971 and 2008, taking individual sibship structure into account. A total of 12,872 cases of infectious mononucleosis were observed during 35.3 million person-years of follow-up. Statistical modelling showed that increasing sibship size was associated with a reduced risk of infectious mononucleosis and that younger siblings conferred more protection from infectious mononucleosis than older siblings. In addition to this general association with younger and older siblings, children aged less than 4 years transiently increased their siblings’ infectious mononucleosis risk. Our results were confirmed in an independent sample of blood donors followed up retrospectively for self-reported infectious mononucleosis. Younger siblings, and to a lesser degree older siblings, seem to be important in the transmission of EBV within families. Apparently the dogma of low birth order in a sibship as being at the highest risk of infectious mononucleosis is no longer valid.

Methodology Series Module 2: Case-control Studies.

Science.gov (United States)

Setia, Maninder Singh

2016-01-01

Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same 'study base' as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive - particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases - selection bias and recall bias.

Risk of schizophrenia in second-generation immigrants: a Danish population-based cohort study

DEFF Research Database (Denmark)

Cantor-Graae, Elizabeth; Pedersen, Carsten Bøcker

2007-01-01

Background. Urban birth, a risk factor for schizophrenia, is more frequent among second-generation immigrants. The aim of the current study was to determine whether the increased risk for schizophrenia found in second-generation immigrants is explained by the degree of urbanization of birthplace...... for urbanization of birthplace and parental characteristics reduced these risks slightly. However, urbanization had a lesser effect in second-generation immigrants than in Danes. History of residence abroad was a risk factor for schizophrenia, regardless of whether parents were foreign-born or native Danes...... and/or factors related to parentage, such as geographic origin or history of residence abroad during upbringing.Method. Using data from the Danish Civil Registration System (CRS), we established a population-based cohort of 2.0 million Danes (persons born in Denmark). Schizophrenia in cohort members...

Residential radon and lung cancer: a cohort study in Galicia, Spain

Directory of Open Access Journals (Sweden)

Raquel Barbosa-Lorenzo

Full Text Available Case-control studies show an association between residential radon and lung cancer. The aim of this paper is to investigate this association through a cohort study. We designed an ambispective cohort study using the Galician radon map, Spain, with controls drawn from a previous case-control study. Subjects were recruited between 2002 and 2009. The data were cross-checked to ascertain lung cancer incidence and then analysed using a Cox regression model. A total of 2,127 subjects participated; 24 lung cancer cases were identified; 76.6% of subjects were drawn from the radon map. The adjusted hazard ratio was 1.2 (95%CI: 0.5-2.8 for the category of subjects exposed to 50Bq/m3 or more. This risk rose when subjects from the case-control study were analyzed separately. In conclusion, we did not observe any statistically significant association between residential radon exposure and lung cancer; however, it appears that with a sample of greater median age (such as participants from the case-control study, the risk of lung cancer would have been higher.

Associations between late and moderately preterm birth and smoking, alcohol, drug use and diet: a population-based case-cohort study.

Science.gov (United States)

Smith, Lucy K; Draper, Elizabeth S; Evans, T Alun; Field, David J; Johnson, Samantha J; Manktelow, Bradley N; Seaton, Sarah E; Marlow, Neil; Petrou, Stavros; Boyle, Elaine M

2015-11-01

This study explores the associations between lifestyle factors and late and moderate preterm birth (LMPT: 32(+0)-36(+6) weeks' gestation), a relatively under-researched group. A population-based case-cohort study was undertaken involving 922 LMPT and 965 term (37+ weeks' gestation) singleton live and stillbirths born between 1 September 2009 and 31 December 2010 to women residing in Leicestershire and Nottinghamshire, UK. Poisson multivariable regression models were fitted to estimate relative risks (RR) of LMPT birth associated with maternal smoking, alcohol and recreational drug use, and diet. Women who smoked during pregnancy were at 38% increased risk of LMPT birth compared with non-smokers (RR 1.38, 95% CI (1.04 to 1.84)). Low consumption of fruit and vegetables was associated with a 31% increased risk compared with those who reported eating higher consumption levels (RR 1.31 (1.03 to 1.66)). Women who did not have any aspects of a Mediterranean diet were nearly twice as likely to deliver LMPT compared with those whose diet included more Mediterranean characteristics (RR 1.81 (1.04 to 3.14)). Women who smoked and consumed low levels of fruit and vegetables (5% of women) were at particularly high risk (RR=1.81 (1.29 to 2.55)). There was no significant effect of alcohol or recreational drug use on LMPT birth. Smoking and poor diet during pregnancy, factors that strongly impact on very preterm birth, are also important at later gestations and experienced together are associated with an elevated rate of risk. Our findings suggest early cessation of smoking during pregnancy may be an effective strategy to reduce LMPT births. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Secondary Analysis under Cohort Sampling Designs Using Conditional Likelihood

Directory of Open Access Journals (Sweden)

Olli Saarela

2012-01-01

Full Text Available Under cohort sampling designs, additional covariate data are collected on cases of a specific type and a randomly selected subset of noncases, primarily for the purpose of studying associations with a time-to-event response of interest. With such data available, an interest may arise to reuse them for studying associations between the additional covariate data and a secondary non-time-to-event response variable, usually collected for the whole study cohort at the outset of the study. Following earlier literature, we refer to such a situation as secondary analysis. We outline a general conditional likelihood approach for secondary analysis under cohort sampling designs and discuss the specific situations of case-cohort and nested case-control designs. We also review alternative methods based on full likelihood and inverse probability weighting. We compare the alternative methods for secondary analysis in two simulated settings and apply them in a real-data example.

Increased Risk of Acute Cholecystitis in Patients with Spinal cord injury: A Nationwide Population-Based Cohort Study.

Science.gov (United States)

Hsu, Cherng-Lan; Wang, Mei-Ting; Ho, Yu-Chun; Pan, Shin-Liang

2017-10-31

Retrospective cohort study. To evaluate the risk of acute cholecystitis (AC) in patients with spinal cord injury (SCI) based on a nationwide sample. Prior research evaluating the risk of AC in patients with SCI is limited. Moreover, since most previous studies on the association between AC and SCI used case-series designs, little is known about the relative risk of SCI patients developing AC from a longitudinal follow-up, compared with individuals without SCI. We used the data from Taiwan's National Health Insurance Research Database. The SCI group consisted of 11523 patients with SCI aged between 20 to 90 years. Propensity score matching procedure was employed to minimize potential confounding effects arising from the imbalance in the baseline characteristics. A total of 23046 propensity score-matched patients without SCI were enrolled in the non-SCI group. We compared the incidence of AC between these two groups, and assessed the impact of SCI on the risk of developing AC. In the SCI and non-SCI groups, the respective incidence rates of AC were 36.9 (95% confidence interval [CI], 30.0 to 44.8) and 25.2 (95% CI, 21.2 to 29.8) per 10000 person-years. As compared to the non-SCI group, the hazard ratio for the SCI group of AC was 1.71 (95% CI, 1.22 to 2.41, P = 0.0018); and the cumulative incidence of AC of the SCI group was higher than that of the non-SCI group (P = 0.0036). This population-based cohort study showed that there was an increased risk of AC in patients with SCI. 3.

The Netherlands Cohort Study – Meat Investigation Cohort; a population-based cohort over-represented with vegetarians, pescetarians and low meat consumers

Science.gov (United States)

2013-01-01

Background Vegetarian diets have been associated with lower risk of chronic disease, but little is known about the health effects of low meat diets and the reliability of self-reported vegetarian status. We aimed to establish an analytical cohort over-represented with vegetarians, pescetarians and 1 day/week meat consumers, and to describe their lifestyle and dietary characteristics. In addition, we were able to compare self-reported vegetarians with vegetarians whose status has been confirmed by their response on the extensive food frequency questionnaire (FFQ). Study methods Embedded within the Netherlands Cohort Study (n = 120,852; including 1150 self-reported vegetarians), the NLCS-Meat Investigation Cohort (NLCS-MIC) was defined by combining all FFQ-confirmed-vegetarians (n = 702), pescetarians (n = 394), and 1 day/week meat consumers (n = 1,396) from the total cohort with a random sample of 2–5 days/week- and 6–7 days/week meat consumers (n = 2,965 and 5,648, respectively). Results Vegetarians, pescetarians, and 1 day/week meat consumers had more favorable dietary intakes (e.g. higher fiber/vegetables) and lifestyle characteristics (e.g. lower smoking rates) compared to regular meat consumers in both sexes. Vegetarians adhered to their diet longer than pescetarians and 1 day/week meat consumers. 75% of vegetarians with a prevalent cancer at baseline had changed to this diet after diagnosis. 50% of self-reported vegetarians reported meat or fish consumption on the FFQ. Although the misclassification that occurred in terms of diet and lifestyle when merely relying on self-reporting was relatively small, the impact on associations with disease risk remains to be studied. Conclusion We established an analytical cohort over-represented with persons at the lower end of the meat consumption spectrum which should facilitate prospective studies of major cancers and causes of death using ≥20.3 years of follow-up. PMID:24289207

Unilateral Vocal Fold Paralysis and Risk of Pneumonia: A Nationwide Population-Based Cohort Study.

Science.gov (United States)

Tsai, Ming-Shao; Yang, Yao-Hsu; Liu, Chia-Yen; Lin, Meng-Hung; Chang, Geng-He; Tsai, Yao-Te; Li, Hsueh-Yu; Tsai, Ying-Huang; Hsu, Cheng-Ming

2018-05-01

Objective To investigate pneumonia risk among patients with unilateral vocal fold paralysis (UVFP). Study Design Retrospective population-based cohort study. Setting This study used data from the National Health Insurance Research Database of Taiwan, a nationwide population-based database. Subjects and Methods A total of 419 patients newly diagnosed with UVFP between January 1, 1997, and December 31, 2013, were identified from the Longitudinal Health Insurance Database 2000, a nationally representative database of 1 million randomly selected patients. Moreover, 1676 patients without UVFP were matched to patients with UVFP at a 1:4 ratio based on age, sex, socioeconomic status, urbanization level, and site-specific cancers. Patients were followed up until death or the end of the study period (December 31, 2013). The primary outcome was the occurrence of pneumonia. Results The cumulative incidence of pneumonia was significantly higher for patients with UVFP than those without UFVP ( P < .001). The adjusted Cox proportional hazard model showed that UVFP was significantly associated with a higher incidence of pneumonia (hazard ratio, 1.97; 95% CI, 1.35-2.86; P < .001). Subgroup analyses demonstrated that UVFP was an independent risk factor of pneumonia for 4 subgroups: young (18-50 years), older (≥51 years), male, and cancer. Conclusion This is the first nationwide population-based cohort study to investigate the association between UVFP and pneumonia. The findings indicate that UVFP is an independent risk factor of pneumonia. Given the study results, physicians should be aware of the potential for pneumonia occurrence following UVFP.

The worsening factors of dengue hemorrhagic fever (DHF) based on cohort study with nested case-control in a tertiary hospital

Science.gov (United States)

Lardo, S.; Soesatyo, M. H. N. E.; Juffrie; Umniyati, S. R.

2018-03-01

The clinical pathway of DHF has a broad pathophysiological and pathogenesis spectrum. Clinical and laboratory characteristics are some of the parameters to determine the factors that contribute to the worsening of the disease. The objective of this study is to determine the clinical and laboratory characteristics which contribute to the worsening of DHF. The study had been conducted from January 2012-December 2014 at the general ward of the Internal Medicine Department, Indonesia Army Central Hospital Gatot Soebroto. There were 101 male patients (64.7%) and 55 female patients (35.3 %) ages ranging from 14 - 62 years old. The diagnosis was divided into: 124 patients DHF grade I, 6 DHF grade II, 20 DHF grade III and 6 with dengue shock syndrome (DSS) patients. Clinically and statistically, there were 4 variables apparently found with the severity of DHF, as follows: decreased appetite with p = 0.007 (OR 4.87), hepatomegaly with p = 0.009 (OR 27.00), systolic blood pressure with p = 0.037 (OR 0.95), and initial thrombocyte with p = 0.000 (OR 0.97). This cohort and nested case-control study found that worsening of DHF is related with decreased appetite, hepatomegaly, systolic blood pressure and initial thrombocyte count.

Necrotizing Fasciitis Associated with Pregnancy: a Population-Based Cohort Study.

Science.gov (United States)

Oud, Lavi; Watkins, Phillip

2014-12-01

Necrotizing fasciitis (NF) is a rare complication in pregnant women. There have been no population-level data reported to date on its epidemiology, clinical features, resource utilization, and outcomes. This was a retrospective, population-based cohort study, using the Texas Inpatient Public Use Data File to identify pregnancy-associated hospitalizations for the years 2001-2010. Hospitalizations with a diagnosis of NF were then identified using the International Classification of Diseases, Ninth Revision, Clinical Modification code 728.86. Denominator data for incidence estimates were derived from the Texas Center for Health Statistics reports of live births, abortions and fetal deaths, and previously reported population-based, age-specific linkage data on miscarriage, and were used to estimate the annual total number of pregnancies (TEP). The incidence of pregnancy-associated NF (PANF), hospitalization type, clinical features, resource utilization and outcomes were examined. There were 4,060,201 pregnancy-associated hospitalizations and 148 PANF hospitalizations during study period. Postpartum hospitalizations accounted for 82.4% of all PANF events, and intensive care unit care was required in 61.5%. The key trends noted between 2001-2002 and 2009-2010 included rising incidence of PANF from 1.1 vs. 3.8 per 100,000 TEP-years (P = 0.0001), chronic comorbidities 0% vs. 31.7% (P = 0.0777), and development of organ failure in 9.1% vs. 31.7% (P = 0.0302). There was no significant change in total hospital charges or hospital length of stay. Three patients (2%) died in the hospital and 55% of survivors had routine home discharge. The present cohort of PANF is the largest reported to date. The incidence of PANF rose nearly 3.5-fold over the past decade, with most events developing following delivery hospitalization. Chronic illness has been increasingly present, along with rising severity of illness. The majority of patients required ICU care. Hospital mortality was

Logistics case study based research: Towards higher quality

DEFF Research Database (Denmark)

Pedrosa, Alex; Näslund, Dag; Jasmand, Claudia

2012-01-01

analysis of 134 case study based articles published in six leading logistics and supply chain management (SCM) journals between 1998 and 2010 is used to assess and evaluate the quality of the case study based research approach as documented in these publications. Findings – This research provides...... to address to ensure high quality of the case study based research approach in published articles. Research limitations/implications – This study is limited to the analysis of published articles in six logistics and SCM journals. Further research should investigate different journals in logistics and other...

Chocolate consumption and risk of stroke among men and women: A large population-based, prospective cohort study.

Science.gov (United States)

Dong, Jia-Yi; Iso, Hiroyasu; Yamagishi, Kazumasa; Sawada, Norie; Tsugane, Shoichiro

2017-05-01

Chocolate consumption may have a beneficial effect on cardiovascular health, but evidence from prospective cohort studies is still limited. We aimed to examine the prospective associations between chocolate consumption and risk of stroke among men and women in a large population-based cohort. A total of 38,182 men and 46,415 women aged 44-76 years, and free of cardiovascular disease, diabetes, and cancer at baseline in 1995 and 1998, were followed up until the end of 2009 and 2010, respectively. We obtained data on chocolate consumption for each participant using a self-administrated food frequency questionnaire that included 138 food and beverage items. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) of stroke in relation to chocolate consumption. During a median follow-up of 12.9 years, we identified 3558 incident strokes cases (2146 cerebral infarctions and 1396 hemorrhagic strokes). After adjustment for age, body mass index, life styles, dietary intakes, and other risk factors, chocolate consumption was associated with a significant lower risk of stroke in women (HR = 0.84; 95% CI, 0.71-0.99). However, the association in men was not significant (HR = 0.94; 95% CI, 0.80-1.10). In addition, the association did not vary by stroke subtypes in either men or women. Findings from this large Japanese cohort supported a significant inverse association between chocolate consumption and risk of developing stroke in women. However, residual confounding could not be excluded as an alternative explanation for our findings. Copyright © 2017 Elsevier B.V. All rights reserved.

HIV incidence from the first population-based cohort study in India.

Science.gov (United States)

Dandona, Lalit; Kumar, G Anil; Lakshmi, Vemu; Ahmed, G Md Mushtaq; Akbar, Mohammed; Ramgopal, Sri P; Sudha, Talasila; Alary, Michel; Dandona, Rakhi

2013-07-17

Understanding about who acquires new HIV infection and the determinants of why some persons get infected and others do not is fundamental to controlling HIV in the population. We assess HIV incidence and its associations in the population of a high HIV burden district in Andhra Pradesh state in southern India by a population-based longitudinal cohort study. We re-surveyed a population-based cohort of 12,617 adults in Guntur district of Andhra Pradesh for which we had reported a baseline HIV prevalence of 1.72% (rural 1.64%, urban 1.89%) among the 15-49 years age group in 2004-2005. We conducted interviews to assess risk behaviour and performed HIV testing again in 2010-2011. We assessed the rate of new HIV infection and its associations using multiple logistic regression. The participation rate in the follow-up was 74.9% and 63.9% of the baseline rural and urban samples, respectively. Over a mean follow-up of 5.63 years, the incidence of HIV was 1.26 per 1000 person-years (95% CI 0.83-1.69), after adjusting for slight compositional bias in the follow-up sample. The incidence per 1000 person-years was higher among rural men (1.68) than urban men (0.85), and among rural women (1.28) than urban women (0.54). The strongest association with incidence was a HIV positive spouse in the baseline for both men (odds ratio 266, 95% CI 62-1137) and women (odds ratio 28, 95% CI 9-88). Among men the other significant associations with HIV incidence were frequent use of condom for sex over the past 6 months, non-circumcision, more than one lifetime woman sex partner or ever visited sex worker, and transport-related occupation; for women the other significant associations were having had HIV testing other than antenatal check-up, previously married but currently not, and tobacco use. These first population-based cohort incidence data from India suggest that rural areas of high HIV burden states would need more attention to prevent new HIV infections, and that spouses of HIV

Risk of Periodontal Disease in Patients With Asthma: A Nationwide Population-Based Retrospective Cohort Study.

Science.gov (United States)

Shen, Te-Chun; Chang, Pei-Ying; Lin, Cheng-Li; Wei, Chang-Ching; Tu, Chih-Yen; Hsia, Te-Chun; Shih, Chuen-Ming; Hsu, Wu-Huei; Sung, Fung-Chang; Kao, Chia-Hung

2017-08-01

Studies have reported an association between asthma and oral diseases, including periodontal diseases. The aim of this retrospective study is to investigate risk of periodontal diseases for patients with asthma. Using the claims data of National Health Insurance of Taiwan and patients without a history of periodontal diseases, 19,206 asthmatic patients, who were newly diagnosed from 2000 through 2010, were identified. For each case, four comparison individuals without history of asthma and periodontal disease were randomly selected from the general population and frequency matched (categorical matched) by sex, age, and year of diagnosis (n = 76,824). Both cohorts were followed to the end of 2011 to monitor occurrence of periodontal diseases. Adjusted hazard ratios (aHRs) of periodontal disease were estimated using Cox proportional hazards regression analysis. Overall incidence of periodontal diseases was 1.18-fold greater in the asthma cohort than in the comparison cohort (P periodontal diseases compared with those with a mean of less than one visit. Patients with at least three admissions annually also had a similar aHR (51.8) for periodontal disease. In addition, asthmatic patients on inhaled corticosteroid (ICS) therapy had greater aHRs than non-users (aHR = 1.12; 95% CI = 1.03 to 1.23). In the studied population, asthmatic patients are at an elevated risk of developing periodontal diseases. The risk is much greater for those with emergency medical demands or hospital admissions and those on ICS treatment.

Cardiovascular disease in patients with osteogenesis imperfecta — a nationwide, register-based cohort study

OpenAIRE

Folkestad, Lars; Hald, Jannie Dahl; Gram, Jeppe; Langdahl, Bente L.; Hermann, Anne Pernille; Diederichsen, Axel CP; Abrahamsen, Bo; Brixen, Kim

2016-01-01

BACKGROUND: Osteogenesis imperfecta (OI) is a hereditary connective tissue disease often due to mutations in genes coding for type 1 collagen. Collagen type 1 is important in the development of the heart and vasculature. Little is known about the risk of cardiovascular disease (CVD) in OI.OBJECTIVE: To investigate the risk of symptomatic CVD in OI.DESIGN: A Danish nationwide, population-based and register-based longitudinal open cohort study.PARTICIPANTS: All patients registered with the diag...

Global teaching and training initiatives for emerging cohort studies

Directory of Open Access Journals (Sweden)

Jessica K. Paulus

2012-09-01

Full Text Available A striking disparity exists across the globe, with essentially no large-scale longitudinal studies ongoing in regions that will be significantly affected by the oncoming non-communicable disease epidemic. The successful implementation of cohort studies in most low-resource research environments presents unique challenges that may be aided by coordinated training programs. Leaders of emerging cohort studies attending the First World Cohort Integration Workshop were surveyed about training priorities, unmet needs and potential cross-cohort solutions to these barriers through an electronic pre-workshop questionnaire and focus groups. Cohort studies representing India, Mexico, Nigeria, South Africa, Sweden, Tanzania and Uganda described similar training needs, including on-the-job training, data analysis software instruction, and database and bio-bank management. A lack of funding and protected time for training activities were commonly identified constraints. Proposed solutions include a collaborative cross-cohort teaching platform with web-based content and interactive teaching methods for a range of research personnel. An international network for research mentorship and idea exchange, and modifying the graduate thesis structure were also identified as key initiatives. Cross-cohort integrated educational initiatives will efficiently meet shared needs, catalyze the development of emerging cohorts, speed closure of the global disparity in cohort research, and may fortify scientific capacity development in low-resource settings.

An ADAM33 polymorphism associates with progression of preschool wheeze into childhood asthma: a prospective case-control study with replication in a birth cohort study.

Directory of Open Access Journals (Sweden)

Ester M M Klaassen

Full Text Available The influence of asthma candidate genes on the development from wheeze to asthma in young children still needs to be defined.To link genetic variants in asthma candidate genes to progression of wheeze to persistent wheeze into childhood asthma.In a prospective study, children with recurrent wheeze from the ADEM (Asthma DEtection and Monitoring study were followed until the age of six. At that age a classification (transient wheeze or asthma was based on symptoms, lung function and medication use. In 198 children the relationship between this classification and 30 polymorphisms in 16 asthma candidate genes was assessed by logistic regression. In case of an association based on a p<0.10, replication analysis was performed in an independent birth cohort study (KOALA study, n = 248 included for the present analysis.In the ADEM study, the minor alleles of ADAM33 rs511898 and rs528557 and the ORMDL3/GSDMB rs7216389 polymorphisms were negatively associated, whereas the minor alleles of IL4 rs2243250 and rs2070874 polymorphisms were positively associated with childhood asthma. When replicated in the KOALA study, ADAM33 rs528557 showed a negative association of the CG/GG-genotype with progression of recurrent wheeze into childhood asthma (0.50 (0.26-0.97 p = 0.04 and no association with preschool wheeze.Polymorphisms in ADAM33, ORMDL3/GSDMB and IL4 were associated with childhood asthma in a group of children with recurrent wheeze. The replication of the negative association of the CG/GG-genotype of rs528557 ADAM33 with childhood asthma in an independent birth cohort study confirms that a compromised ADAM33 gene may be implicated in the progression of wheeze into childhood asthma.

Modifiable etiological factors and the burden of stroke from the Rotterdam study: a population-based cohort study.

Directory of Open Access Journals (Sweden)

Michiel J Bos

2014-04-01

Full Text Available BACKGROUND: Stroke prevention requires effective treatment of its causes. Many etiological factors for stroke have been identified, but the potential gain of effective intervention on these factors in terms of numbers of actually prevented strokes remains unclear because of the lack of data from cohort studies. We assessed the impact of currently known potentially modifiable etiological factors on the occurrence of stroke. METHODS AND FINDINGS: This population-based cohort study was based on 6,844 participants of the Rotterdam Study who were aged ≥55 y and free from stroke at baseline (1990-1993. We computed population attributable risks (PARs for individual risk factors and for risk factors in combination to estimate the proportion of strokes that could theoretically be prevented by the elimination of etiological factors from the population. The mean age at baseline was 69.4 y (standard deviation 6.3 y. During follow-up (mean follow-up 12.9 y, standard deviation 6.3 y, 1,020 strokes occurred. The age- and sex-adjusted combined PAR of prehypertension/hypertension, smoking, diabetes mellitus, atrial fibrillation, coronary disease, and overweight/obesity was 0.51 (95% CI 0.41-0.62 for any stroke; hypertension and smoking were the most important etiological factors. C-reactive protein, fruit and vegetable consumption, and carotid intima-media thickness in combination raised the total PAR by 0.06. The PAR was 0.55 (95% CI 0.41-0.68 for ischemic stroke and 0.70 (95% CI 0.45-0.87 for hemorrhagic stroke. The main limitations of our study are that our study population comprises almost exclusively Caucasians who live in a middle and high income area, and that risk factor awareness is higher in a study cohort than in the general population. CONCLUSIONS: About half of all strokes are attributable to established causal and modifiable factors. This finding encourages not only intervention on established etiological factors, but also further study of less

A prospective cohort study on vegetable and fruit consumption and stomach cancer risk in the netherlands

NARCIS (Netherlands)

Botterweck, A.A.M.; Brandt, P.A. van den; Goldbohm, R.A.

1998-01-01

The association between vegetable and fruit consumption and stomach cancer risk was investigated in the Netherlands Cohort Study among 120,852 men and women aged 55-69 years at the start in September 1986. Analyses were based on 282 incident stomach cancer cases after 6.3 years of follow-up. Age-

Cohort-based income gradients in obesity among U.S. adults.

Science.gov (United States)

Heo, Jongho; Beck, Audrey N; Lin, Shih-Fan; Marcelli, Enrico; Lindsay, Suzanne; Karl Finch, Brian

2018-03-01

No studies have focused on socioeconomic disparities in obesity within and between cohorts. Our objectives were to examine income gradients in obesity between birth-cohorts (inter-cohort variations) and within each birth-cohort (intra-cohort variations) by gender and race/ethnicity. Our sample includes 56,820 white and black adults from pooled, cross-sectional National Health and Nutrition Examination Surveys (1971-2012). We fit a series of logistic hierarchical Age-Period-Cohort models to control for the effects of age and period, simultaneously. Predicted probabilities of obesity by poverty-to-income ratio were estimated and graphed for 5-year cohort groups from 1901-1990. We also stratified this relationship for four gender and racial/ethnic subgroups. Obesity disparities due to income were weaker for post-World War I and II generations, specifically the mid-1920s and the mid-1940s to 1950s cohorts, than for other cohorts. In contrast, we found greater income gradients in obesity among cohorts from the 1930s to mid-1940s and mid-1960s to 1970s. Moreover, obesity disparities due to income across cohorts vary markedly by gender and race/ethnicity. White women with higher income consistently exhibited a lower likelihood of obesity than those with lower income since early 1900s cohorts; whereas, black men with higher income exhibited higher risks of obesity than those with lower income in most cohorts. Our findings suggest that strategies that address race and/or gender inequalities in obesity should be cognizant of significant historical factors that may be unique to cohorts. Period-based approaches that ignore life-course experiences captured in significant cohort-based experiences may limit the utility of policies and interventions. © 2017 Wiley Periodicals, Inc.

Secondary depression in severe anxiety disorders: a population-based cohort study in Denmark

Science.gov (United States)

Meier, Sandra M; Petersen, Liselotte; Mattheisen, Manuel; Mors, Ole; Mortensen, Preben B; Laursen, Thomas M

2016-01-01

Summary Background Depression and anxiety disorders are highly comorbid conditions and a worldwide disease burden; however, large-scale studies delineating their association are scarce. In this retrospective study, we aimed to assess the effect of severe anxiety disorders on the risk and course of depression. Methods We did a population-based cohort study with prospectively gathered data in Denmark using data from three Danish population registers: The Danish Civil Registration System, the Danish Psychiatric Central Register, and the Danish National Hospital Registry. We selected the cohort from people born in Denmark between Jan 1, 1955, and Dec 31, 2002, who we followed up from Jan 1, 1994, to Dec 31, 2012. The cohort was restricted to individuals with known parents. First, we investigated the effect of specific anxiety diagnoses on risk of single depressive episodes and recurrent depressive disorder. Second, we investigated the effect of comorbid anxiety on risk of readmission for depression, adjusting for sex, age, calendar year, parental age, place at residence at time of birth, and the interaction of age with sex. Findings We included 3 380 059 individuals in our study cohort. The adjusted incidence rate ratio (IRR) for single depressive episodes was 3·0 (95% CI 2·8–3·1, pdepressive disorder was 5·0 (4·8–5·2) in patients with severe anxiety disorders compared with the general population. Compared with control individuals, the offspring of parents with anxiety disorders were more likely to be diagnosed with single depressive episodes (1·9, 1·8–2·0) or recurrent depressive disorder (2·1, 1·9–2·2). Comorbid anxiety increased the readmission rates in both patients with single depressive episodes and patients with recurrent depressive disorder. Interpretation Severe anxiety constitutes a significant risk factor for depression. Focusing on specific anxiety disorders might help to identify individuals at risk of depression, thereby providing new

Association between adult otitis media and nasopharyngeal cancer: A nationwide population-based cohort study

International Nuclear Information System (INIS)

Huang, Wen-Yen; Lin, Che-Chen; Jen, Yee-Min; Lin, Kuen-Tze; Yang, Muh-Hwa; Chen, Chang-Ming; Chang, Ying-Nan; Sung, Fung-Chang; Kao, Chia-Hung

2012-01-01

Purpose: To determine whether the diagnosis of otitis media (OM) in adults is associated with an increased risk for the subsequent development of nasopharyngeal cancer (NPC) using a nationwide population-based retrospective study. Methods and materials: We selected 13,513 adult patients that had been previously diagnosed with OM between 2000 and 2005 from the Taiwan Longitudinal Health Insurance Database 2000 as the study cohort, and randomly extracted the data of 135,130 participants matched by sex, age, and baseline year for the comparison cohort. The follow-up period was terminated upon developing NPC, withdrawal from the national health insurance system, or the end of 2009. Cumulative incidences and hazard ratios (HRs) of NPC development were determined. Results: The subsequent NPC incidence rates in the OM and comparison cohorts were 6.41 and 0.58 per 10 000 person-years, respectively (adjusted HR, 11.04; 95% CI, 7.68–5.87; P < 0.0001). The NPC risk for males was significantly higher than that for females (adjusted HR = 3.24; 95% CI, 2.16–4.85). In both female and male patients, the diagnosis of OM was associated with a significantly increased risk for NPC (adjusted HR, 11.91 vs. 10.78, respectively). Among the OM cohort, 62 participants were subsequently diagnosed with NPC, with 71% of them occurring within 1 year following the diagnosis of OM. However, even after 5-year follow-up, the OM cohort still displayed a higher risk for NPC (adjusted HR = 2.50). Stratified by the frequency of OM episodes, more than one episode per year had a significantly greater risk of developing NPC, compared with the comparison cohort (HR = 29.22; 95% CI, 20.19–42.27). Conclusion: We found that adult OM is a warning sign for the development of NPC in Taiwan, with approximately an 11-fold higher risk for adult OM patients. We recommend that OM patients undergo follow-up examinations for at least 5 years. To extrapolate our findings, further studies are warranted in other

Anthropometry, physical activity, and endometrial cancer risk: Results from the Netherlands Cohort Study

NARCIS (Netherlands)

Schouten, L.J.; Goldbohm, R.A.; Brandt, P.A. van den

2004-01-01

Although obesity is an established risk factor for endometrial cancer, evidence linking risk to height, weight change since age 20, and physical activity is limited. In this case-cohort study, 62 573 women from The Netherlands Cohort Study on Diet and Cancer were followed up from 1986 to 1995, and

Public perceptions of cohort studies and biobanks in Germany.

Science.gov (United States)

Starkbaum, Johannes; Gottweis, Herbert; Gottweis, Ursula; Kleiser, Christina; Linseisen, Jakob; Meisinger, Christa; Kamtsiuris, Panagiotis; Moebus, Susanne; Jöckel, Karl-Heinz; Börm, Sonja; Wichmann, H-Erich

2014-04-01

Cohort studies and biobank projects have led to public discussions in several European countries in the past. In Germany, many medium-sized studies are currently running successfully in terms of respondent rates. However, EU-wide research on general public perceptions of biobanks and cohort studies have shown that Germany is among those countries where people express the highest reluctance for providing body material and other data for research purposes. Because of early efforts of the just-initiated German National Cohort Study, we are able to begin to investigate in greater detail how various groups of people across Germany reflect and discuss the ongoing implementation of cohort studies and biobanking in Germany. Our research is based on 15 focus group discussions in four German regions, as well as on Eurobarometer poll data on biobanking.

Weight at birth and subsequent fecundability: a prospective cohort study

DEFF Research Database (Denmark)

Nielsen, Cathrine Wildenschild; Hammerich Riis, Anders; Ehrenstein, Vera

2014-01-01

OBJECTIVE: To examine the association between a woman's birth weight and her subsequent fecundability. METHOD: In this prospective cohort study, we included 2,773 Danish pregnancy planners enrolled in the internet-based cohort study "Snart-Gravid", conducted during 2007-2012. Participants were 18...

Cohort-Based Identification of Predictors of Symptomatic Intracerebral Hemorrhage After IV Thrombolysis.

Science.gov (United States)

Asuzu, David; Nyström, Karin; Amin, Hardik; Schindler, Joseph; Wira, Charles; Greer, David; Chi, Nai Fang; Halliday, Janet; Sheth, Kevin N

2015-12-01

Symptomatic intracranial hemorrhage (sICH) is a serious complication of IV rt-PA therapy after acute ischemic stroke. Independent sICH predictors have been previously derived using case-control studies. Here we utilized a novel cohort-based comparison to identify additional independent predictors of sICH. We included 210 patients receiving IV rt-PA therapy from January 2009 through December 2013 at the Yale-New Haven Stroke Center. Clinical parameters were compared using Mann-Whitney tests, two-sample tests of proportions and two-sample t tests. Logistic regression was performed using sICH as the dependent variable. Predictive ability was assessed using areas under the receiver operating characteristic (ROC) curve. sICH rates were lowest from 2010 to 2012 and comprised the low sICH cohort (2.0 % sICH), compared to the high sICH cohort from 2009 to 2013 (9.2 % sICH, P = 0.025). Patients in the low sICH cohort had significantly more visual field deficits (38.6 vs. 24.8 %, P = 0.03) and decreased levels of consciousness (62.4 vs. 39.4 %, P vs. 13.8 %, P = 0.03) and early CT hypodensities (14.9 vs. 29.4 %, P = 0.01). These four parameters together predicted sICH modestly (area under ROC curve 0.66, odds ratio 2.72, P = 0.03) CONCLUSIONS: Using a novel cohort-based approach, we identified two new independent predictors of sICH after IV rt-PA therapy: the presence of the hyperdense MCA sign and early CT hypodensities. Novel methods are needed to reduce the risk of sICH for patients receiving antithrombolytic therapy for ischemic stroke.

1970 British Cohort Study

Directory of Open Access Journals (Sweden)

Matt Brown

2014-10-01

Full Text Available The 1970 British Cohort Study (BCS70 is one of Britain’s world famous national longitudinal birth cohort studies, three of which are run by the Centre for Longitudinal Studies at the Institute of Education, University of London.  BCS70 follows the lives of more than 17,000 people born in England, Scotland and Wales in a single week of 1970. Over the course of cohort members lives, the BCS70 has collected information on health, physical, educational and social development, and economic circumstances among other factors. Since the birth survey in 1970, there have been nine ‘sweeps’ of all cohort members at ages 5, 10, 16, 26, 30, 34, 38 and most recently at 42. Data has been collected from a number of different sources (the midwife present at birth, parents of the cohort members, head and class teachers, school health service personnel and the cohort members themselves. The data has been collected in a variety of ways including via paper and electronic questionnaires, clinical records, medical examinations, physical measurements, tests of ability, educational assessments and diaries. The majority of BCS70 survey data can be accessed by bona fide researchers through the UK Data Service at the University of Essex.

RANTES/CCL5 and risk for coronary events: results from the MONICA/KORA Augsburg case-cohort, Athero-Express and CARDIoGRAM studies.

Directory of Open Access Journals (Sweden)

Christian Herder

Full Text Available The chemokine RANTES (regulated on activation, normal T-cell expressed and secreted/CCL5 is involved in the pathogenesis of cardiovascular disease in mice, whereas less is known in humans. We hypothesised that its relevance for atherosclerosis should be reflected by associations between CCL5 gene variants, RANTES serum concentrations and protein levels in atherosclerotic plaques and risk for coronary events.We conducted a case-cohort study within the population-based MONICA/KORA Augsburg studies. Baseline RANTES serum levels were measured in 363 individuals with incident coronary events and 1,908 non-cases (mean follow-up: 10.2±4.8 years. Cox proportional hazard models adjusting for age, sex, body mass index, metabolic factors and lifestyle factors revealed no significant association between RANTES and incident coronary events (HR [95% CI] for increasing RANTES tertiles 1.0, 1.03 [0.75-1.42] and 1.11 [0.81-1.54]. None of six CCL5 single nucleotide polymorphisms and no common haplotype showed significant associations with coronary events. Also in the CARDIoGRAM study (>22,000 cases, >60,000 controls, none of these CCL5 SNPs was significantly associated with coronary artery disease. In the prospective Athero-Express biobank study, RANTES plaque levels were measured in 606 atherosclerotic lesions from patients who underwent carotid endarterectomy. RANTES content in atherosclerotic plaques was positively associated with macrophage infiltration and inversely associated with plaque calcification. However, there was no significant association between RANTES content in plaques and risk for coronary events (mean follow-up 2.8±0.8 years.High RANTES plaque levels were associated with an unstable plaque phenotype. However, the absence of associations between (i RANTES serum levels, (ii CCL5 genotypes and (iii RANTES content in carotid plaques and either coronary artery disease or incident coronary events in our cohorts suggests that RANTES may not be a

The Misconception of Case-Control Studies in the Plastic Surgery Literature: A Literature Audit.

Science.gov (United States)

Hatchell, Alexandra C; Farrokhyar, Forough; Choi, Matthew

2017-06-01

Case-control study designs are commonly used. However, many published case-control studies are not true case-controls and are in fact mislabeled. The purpose of this study was to identify all case-control studies published in the top three plastic surgery journals over the past 10 years, assess which were truly case-control studies, clarify the actual design of the articles, and address common misconceptions. MEDLINE, Embase, and Web of Science databases were searched for case-control studies in the three highest-impact factor plastic surgery journals (2005 to 2015). Two independent reviewers screened the resulting titles, abstracts, and methods, if applicable, to identify articles labeled as case-control studies. These articles were appraised and classified as true case-control studies or non-case-control studies. The authors found 28 articles labeled as case-control studies. However, only six of these articles (21 percent) were truly case-control designs. Of the 22 incorrectly labeled studies, one (5 percent) was a randomized controlled trial, three (14 percent) were nonrandomized trials, two (9 percent) were prospective comparative cohort designs, 14 (64 percent) were retrospective comparative cohort designs, and two (9 percent) were cross-sectional designs. The mislabeling was worse in recent years, despite increases in evidence-based medicine awareness. The majority of published case-control studies are not in fact case-control studies. This misunderstanding is worsening with time. Most of these studies are actually comparative cohort designs. However, some studies are truly clinical trials and thus a higher level of evidence than originally proposed.

Analysis of 1:1 Matched Cohort Studies and Twin Studies, with Binary Exposures and Binary Outcomes

OpenAIRE

Sjölander, Arvid; Johansson, Anna L. V.; Lundholm, Cecilia; Altman, Daniel; Almqvist, Catarina; Pawitan, Yudi

2012-01-01

To improve confounder adjustments, observational studies are often matched on potential confounders. While matched case-control studies are common and well covered in the literature, our focus here is on matched cohort studies, which are less common and sparsely discussed in the literature. Matched data also arise naturally in twin studies, as a cohort of exposure–discordant twins can be viewed as being matched on a large number of potential confounders. The analysis of twin studies will be g...

Case-control cohort study of patients' perceptions of disability in mastocytosis.

Directory of Open Access Journals (Sweden)

Olivier Hermine

Full Text Available BACKGROUND: Indolent forms of mastocytosis account for more than 90% of all cases, but the types and type and severity of symptoms and their impact on the quality of life have not been well studied. We therefore performed a case-control cohort study to examine self-reported disability and impact of symptoms on the quality of life in patients with mastocytosis. METHODOLOGY/PRINCIPAL FINDINGS: In 2004, 363 mastocytosis patients and 90 controls in France were asked to rate to their overall disability (OPA score and the severity of 38 individual symptoms. The latter was used to calculate a composite score (AFIRMM score. Of the 363 respondents, 262 were part of an ongoing pathophysiological study so that the following data were available: World Health Organization classification, standard measures of physical and psychological disability, existence of the D816V KIT mutation, and serum tryptase level. The mean OPA and AFIRMM scores and the standard measures of disability indicated that most mastocytosis patients suffer from disabilities due to the disease. Surprisingly, the patient's measurable and perceived disabilities did not differ according to disease classification or presence or absence of the D816V KIT mutation or an elevated (> or = 20 ng/mL serum tryptase level. Also, 32 of the 38 AFIRMM symptoms were more common in patients than controls, but there were not substantial differences according to disease classification, presence of the D816V mutation, or the serum tryptase level. CONCLUSIONS: On the basis of these results and for the purposes of treatment, we propose that mastocytosis be first classified as aggressive or indolent and that indolent mastocytosis then be categorized according to the severity of patients' perceived symptoms and their impact on the quality of life. In addition, it appears that mastocytosis patients suffer from more symptoms and greater disability than previously thought, that mastocytosis may therefore be under

Transmissibility of the Ice Bucket Challenge among globally influential celebrities: retrospective cohort study

Science.gov (United States)

Chan, Brandford H Y; Leung, Gabriel M; Lau, Eric H Y; Pang, Herbert

2014-01-01

Objectives To estimate the transmissibility of the Ice Bucket Challenge among globally influential celebrities and to identify associated risk factors. Design Retrospective cohort study. Setting Social media (YouTube, Facebook, Twitter, Instagram). Participants David Beckham, Cristiano Ronaldo, Benedict Cumberbatch, Stephen Hawking, Mark Zuckerberg, Oprah Winfrey, Homer Simpson, and Kermit the Frog were defined as index cases. We included contacts up to the fifth generation seeded from each index case and enrolled a total of 99 participants into the cohort. Main outcome measures Basic reproduction number R0, serial interval of accepting the challenge, and odds ratios of associated risk factors based on fully observed nomination chains; R0 is a measure of transmissibility and is defined as the number of secondary cases generated by a single index in a fully susceptible population. Serial interval is the duration between onset of a primary case and onset of its secondary cases. Results Based on the empirical data and assuming a branching process we estimated a mean R0 of 1.43 (95% confidence interval 1.23 to 1.65) and a mean serial interval for accepting the challenge of 2.1 days (median 1 day). Higher log (base 10) net worth of the participants was positively associated with transmission (odds ratio 1.63, 95% confidence interval 1.06 to 2.50), adjusting for age and sex. Conclusions The Ice Bucket Challenge was moderately transmissible among a group of globally influential celebrities, in the range of the pandemic A/H1N1 2009 influenza. The challenge was more likely to be spread by richer celebrities, perhaps in part reflecting greater social influence. PMID:25514905

Transmissibility of the Ice Bucket Challenge among globally influential celebrities: retrospective cohort study.

Science.gov (United States)

Ni, Michael Y; Chan, Brandford H Y; Leung, Gabriel M; Lau, Eric H Y; Pang, Herbert

2014-12-16

To estimate the transmissibility of the Ice Bucket Challenge among globally influential celebrities and to identify associated risk factors. Retrospective cohort study. Social media (YouTube, Facebook, Twitter, Instagram). David Beckham, Cristiano Ronaldo, Benedict Cumberbatch, Stephen Hawking, Mark Zuckerberg, Oprah Winfrey, Homer Simpson, and Kermit the Frog were defined as index cases. We included contacts up to the fifth generation seeded from each index case and enrolled a total of 99 participants into the cohort. Basic reproduction number R0, serial interval of accepting the challenge, and odds ratios of associated risk factors based on fully observed nomination chains; R0 is a measure of transmissibility and is defined as the number of secondary cases generated by a single index in a fully susceptible population. Serial interval is the duration between onset of a primary case and onset of its secondary cases. Based on the empirical data and assuming a branching process we estimated a mean R0 of 1.43 (95% confidence interval 1.23 to 1.65) and a mean serial interval for accepting the challenge of 2.1 days (median 1 day). Higher log (base 10) net worth of the participants was positively associated with transmission (odds ratio 1.63, 95% confidence interval 1.06 to 2.50), adjusting for age and sex. The Ice Bucket Challenge was moderately transmissible among a group of globally influential celebrities, in the range of the pandemic A/H1N1 2009 influenza. The challenge was more likely to be spread by richer celebrities, perhaps in part reflecting greater social influence. © Ni et al 2014.

Using Case Studies in Calculus-based Physics

Science.gov (United States)

Katz, Debora M.

2006-12-01

Do your students believe that the physics only works in your classroom or laboratory? Or do they see that physics underlies their everyday experience? Case studies in physics help students connect physics principles to their everyday experience. For decades, case studies have been used to teach law, medicine and biology, but they are rarely used in physics. I am working on a calculus-based physics textbook for scientists and engineers. Case studies are woven into each chapter. Stop by and get a case study to test out in your classroom. I would love to get your feedback.

Increased incidence of peptic ulcer disease in central serous chorioretinopathy patients: a population-based retrospective cohort study.

Science.gov (United States)

Chen, San-Ni; Lian, Iebin; Chen, Yi-Chiao; Ho, Jau-Der

2015-02-01

To investigate peptic ulcer disease and other possible risk factors in patients with central serous chorioretinopathy (CSR) using a population-based database. In this population-based retrospective cohort study, longitudinal data from the Taiwan National Health Insurance Research Database were analyzed. The study cohort comprised 835 patients with CSR and the control cohort comprised 4175 patients without CSR from January 2000 to December 2009. Conditional logistic regression was applied to examine the association of peptic ulcer disease and other possible risk factors for CSR, and stratified Cox regression models were applied to examine whether patients with CSR have an increased chance of peptic ulcer disease and hypertension development. The identifiable risk factors for CSR included peptic ulcer disease (adjusted odd ratio: 1.39, P = 0.001) and higher monthly income (adjusted odd ratio: 1.30, P = 0.006). Patients with CSR also had a significantly higher chance of developing peptic ulcer disease after the diagnosis of CSR (adjusted odd ratio: 1.43, P = 0.009). Peptic ulcer disease and higher monthly income are independent risk factors for CSR. Whereas, patients with CSR also had increased risk for peptic ulcer development.

Increased dementia risk predominantly in diabetes mellitus rather than in hypertension or hyperlipidemia: a population-based cohort study.

Science.gov (United States)

Fan, Yen-Chun; Hsu, Jung-Lung; Tung, Hong-Yi; Chou, Chia-Chi; Bai, Chyi-Huey

2017-02-06

The pathophysiology of insulin resistance-induced hypertension and hyperlipidemia might entail differences in dementia risk in cases with hypertension and hyperlipidemia without prior diabetes mellitus (DM). This study investigated whether incident hypertension, incident hyperlipidemia, or both, increased the dementia risk in patients with and without DM. A nationwide retrospective cohort study was conducted. The study sample was obtained from the National Health Insurance Research Database. We enrolled 10,316 patients with a new diagnosis of DM between 2000 and 2002 in the DM cohort. For the same period, we randomly selected 41,264 patients without DM in the non-DM cohort (matched by age and sex at a 1:4 ratio with the DM cohort). Both cohorts were then separately divided into four groups on the basis of incident hypertension or incident hyperlipidemia status. In total, 51,580 patients aged between 20 and 99 years were enrolled. The dementia risk was higher in the DM cohort than in the non-DM cohort (adjusted hazard ratio (HR) = 1.47, 95% confidence interval (CI) = 1.30-1.67, p hypertension and hyperlipidemia did not significantly increase compared with that in those without hypertension and hyperlipidemia (p = 0.529). Similar results were observed in those with either hypertension (p = 0.341) or hyperlipidemia (p = 0.189). In the non-DM cohort, patients with both hypertension and hyperlipidemia had a higher dementia risk (adjusted HR = 1.33, 95% CI = 1.09-1.63, p = 0.006). The results remained largely unchanged in patients with only hypertension (adjusted HR = 1.22, 95% CI = 1.05-1.40, p = 0.008). However, the dementia risk did not increase significantly in patients with only hyperlipidemia (p = 0.187). The development of hypertension, hyperlipidemia, or both, following a diagnosis of incident diabetes is secondary to diabetes onset and likely mediated through insulin resistance associated with diabetes, which

VTE Risk assessment - a prognostic Model: BATER Cohort Study of young women.

Science.gov (United States)

Heinemann, Lothar Aj; Dominh, Thai; Assmann, Anita; Schramm, Wolfgang; Schürmann, Rolf; Hilpert, Jan; Spannagl, Michael

2005-04-18

BACKGROUND: Community-based cohort studies are not available that evaluated the predictive power of both clinical and genetic risk factors for venous thromboembolism (VTE). There is, however, clinical need to forecast the likelihood of future occurrence of VTE, at least qualitatively, to support decisions about intensity of diagnostic or preventive measures. MATERIALS AND METHODS: A 10-year observation period of the Bavarian Thromboembolic Risk (BATER) study, a cohort study of 4337 women (18-55 years), was used to develop a predictive model of VTE based on clinical and genetic variables at baseline (1993). The objective was to prepare a probabilistic scheme that discriminates women with virtually no VTE risk from those at higher levels of absolute VTE risk in the foreseeable future. A multivariate analysis determined which variables at baseline were the best predictors of a future VTE event, provided a ranking according to the predictive power, and permitted to design a simple graphic scheme to assess the individual VTE risk using five predictor variables. RESULTS: Thirty-four new confirmed VTEs occurred during the observation period of over 32,000 women-years (WYs). A model was developed mainly based on clinical information (personal history of previous VTE and family history of VTE, age, BMI) and one composite genetic risk markers (combining Factor V Leiden and Prothrombin G20210A Mutation). Four levels of increasing VTE risk were arbitrarily defined to map the prevalence in the study population: No/low risk of VTE (61.3%), moderate risk (21.1%), high risk (6.0%), very high risk of future VTE (0.9%). In 10.6% of the population the risk assessment was not possible due to lacking VTE cases. The average incidence rates for VTE in these four levels were: 4.1, 12.3, 47.2, and 170.5 per 104 WYs for no, moderate, high, and very high risk, respectively. CONCLUSION: Our prognostic tool - containing clinical information (and if available also genetic data) - seems to be

The association between spinal cord injury and acute myocardial infarction in a nationwide population-based cohort study.

Science.gov (United States)

Yang, Tse-Yen; Chen, Hsuan-Ju; Sung, Fung-Chang; Kao, Chia-Hung

2015-02-01

A spinal cord injury (SCI) retrospective cohort study was derived from the National Health Insurance Research Database of Taiwan. We evaluated risk of acute myocardial infarction (AMI) in patients newly diagnosed with SCI. According to information of the World Health Organization, cardiovascular diseases are the most frequent causes of death in patients with SCI compared with those in the general population. We obtained claims data from the National Health Insurance Research Database for this cohort study. The SCI group comprised 22,197 patients with a diagnosis of SCI. Case and control patients were based on risk-set sampling in a 1:4 ratio, and we excluded patients with a prior diagnosis of AMI. Comorbidities were categorized as the proportion of prior illnesses in the SCI and non-SCI groups. We used the Cox proportion model to explore adjusted hazard ratio (aHR) for developing AMI between case and control patients. Patients with SCI were significantly more likely to exhibit pre-existing illnesses associated with AMI than patients without SCI. Patients with a diagnosis of SCI exhibited significantly higher aHRs for developing AMI than patients without SCI (aHR=1.17; P<0.05). Patients with SCI, compared with patients without SCI, were associated with a subsequent AMI risk (aHR=1.17; P<0.05). Several comorbidities, such as cardiovascular disease (aHR=1.29; P<0.05), chronic obstructive pulmonary disease (aHR=1.51; P<0.05), hypertension (aHR=1.34; P<0.01), and renal disease (aHR=1.76; P<0.05), were associated with an increased AMI risk. Furthermore, T-spine SCI was significantly associated with an AMI risk (aHR=1.38; P<0.05). Patients with as diagnosis of SCI exhibited an increased risk of AMI compared with patients without SCI. These findings have broad implications for surveillance among patients with SCI, and future studies should evaluate whether risk factor modification can decrease AMI risk among patients with SCI. 3.

Hyperthyroidism and thyroid cancer risk: a population-based cohort study.

Science.gov (United States)

Yeh, N-C; Chou, C-W; Weng, S-F; Yang, C-Y; Yen, F-C; Lee, S-Y; Wang, J-J; Tien, K-J

2013-07-01

Thyroid hormones regulate the rate of metabolism and affect the differentiation and growth of many tissues in the body. We investigated the association between hyperthyroidism and cancer risk in Taiwan. A random sample of 1 000 000 individuals from Taiwan's National Health Insurance database was enrolled. We found 17 033 patients to have newly diagnosed hyperthyroidism between 2000 and 2005. These patients were recruited along with a match cohort of 34 066 patients without hyperthyroidism. Starting from index date, we followed up all patients for 4 years to identify those who developed cancer. During the 4-year follow-up study, cancer was diagnosed in 1.23% of patients with hyperthyroidism and 1.02% of the member of the comparison cohort. Regression analysis showed that patients with hyperthyroidism were at greater risk of cancer incidence, especially thyroid cancer, compared the comparison cohort (HR: 1.213; 95% CI: 1.022-1.440; phyperthyroidism remained at increased risk of cancer incidence and thyroid cancer (Adjusted HR: 1.206; 95% CI: 1.015-1.433 and 6.803; 95% CI: 3.584-12.91, respectively) (both phyperthyroidism, the greater the risk of thyroid cancer. This 4-year follow up study suggests that patients with hyperthyroidism are at increased risk of cancer, especially thyroid cancer. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

Factors associated with Clostridium difficile infection: A nested case-control study in a three year prospective cohort.

Science.gov (United States)

Khanafer, Nagham; Vanhems, Philippe; Barbut, Frédéric; Luxemburger, Christine

2017-04-01

Clostridium difficile infection (CDI) is a serious medical condition that is associated with substantial morbidity and mortality. Identification of risk factors associated with CDI and prompt recognition of patients at risk is key to successfully preventing CDI. A 3-year prospective, observational, cohort study was conducted in a French university hospital and a nested case-control study was performed to identify risk factors for CDI. Inpatients aged 18 years or older, suffering from diarrhea suspected to be related to CDI, were asked to participate. A total of 945 patients were included, of which 233 cases had a confirmed CDI. CDI infection was more common in men (58.4%) (P = 0.04) compared with patients with diarrhea not related to C. difficile. Previous hospitalization (P infection control issues. In future, these "high-risk" patients may benefit from novel agents being developed to prevent CDI. Copyright © 2017 Elsevier Ltd. All rights reserved.

Student Response to Remote-Online Case-Based Learning: A Qualitative Study.

Science.gov (United States)

Nicklen, Peter; Keating, Jennifer L; Maloney, Stephen

2016-03-22

Case-based learning (CBL) typically involves face-to-face interaction in small collaborative groups with a focus on self-directed study. To our knowledge, no published studies report an evaluation of Web conferencing in CBL. The primary aim of this study was to explore student perceptions and attitudes in response to a remote-online case-based learning (RO-CBL) experience. This study took place over a 2-week period in 2013 at Monash University, Victoria, Australia. A third year cohort (n=73) of physiotherapy students was invited to participate. Students were required to participate in 2 training sessions, followed by RO-CBL across 2 sessions. The primary outcome of interest was the student feedback on the quality of the learning experience during RO-CBL participation. This was explored with a focus group and a survey. Most students (68/73) completed the postintervention survey (nonparticipation rate 8%). RO-CBL was generally well received by participants, with 59% (40/68) of participates stating that they'd like RO-CBL to be used in the future and 78% (53/68) of participants believing they could meet the CBL's learning objectives via RO-CBL. The 4 key themes relevant to student response to RO-CBL that emerged from the focus groups and open-ended questions on the postintervention survey were how RO-CBL compared to expectations, key benefits of RO-CBL including flexibility and time and cost savings, communication challenges in the online environment compared to face-to-face, and implications of moving to an online platform. Web conferencing may be a suitable medium for students to participate in CBL. Participants were satisfied with the learning activity and felt they could meet the CBL's learning objectives. Further study should evaluate Web conferencing CBL across an entire semester in regard to student satisfaction, perceived depth of learning, and learning outcomes.

Natural history and surgical treatment of chordoma: a retrospective cohort study

Directory of Open Access Journals (Sweden)

Samuel Aguiar Júnior

Full Text Available CONTEXT AND OBJECTIVE: Chordoma is a rare tumor with a high risk of locoregional recurrences. The aim of this study was analyze the long-term results from treating this pathological condition.DESIGN AND SETTING: Cohort study in a single hospital in São Paulo, Brazil.METHODS: This was a retrospective cohort study on 42 patients with chordoma who were treated at Hospital A. C. Camargo between 1980 and 2006. The hospital records were reviewed and a descriptive analysis was performed on the clinical-pathological variables. Survival curves were estimated using the Kaplan-Meier method and these were compared using the log-rank test.RESULTS: Nineteen patients were men and 23 were women. Twenty-five tumors (59.5% were located in the sacrum, eleven (26.2% in the skull base and six (14.3% in the mobile spine. Surgery was performed on 28 patients (66.7%. The resection was considered to have negative margins in 14 cases and positive margins in 14 cases. The five-year overall survival (OS was 45.4%. For surgical patients, the five-year OS was 64.3% (82.2% for negative margins and 51.9% for positive margins. In the inoperable group, OS was 37.7% at 24 months and 0% at five years.CONCLUSION: Complete resection is related to local control and definitively has a positive impact on long-term survival.

Female schizophrenia patients and risk of breast cancer: A population-based cohort study.

Science.gov (United States)

Wu Chou, Ana Isabel; Wang, Yu-Chiao; Lin, Cheng-Li; Kao, Chia-Hung

2017-10-01

Breast cancer is the most common type of cancer in women. This population-based cohort study aimed to examine the association between breast cancer in female schizophrenia patients and its association with the use of antipsychotics drugs. All study subjects were selected from the Taiwan Insurance Claims Data (1998-2008). We compared the risk for breast cancer between female schizophrenia patients receiving antipsychotics (n=29,641) with female patients without any serious mental illnesses nor receiving antipsychotic drugs (n=59,282). We also compared between patients on 1) first-generation antipsychotics (FGAs) alone; 2) combination of first and second generation antipsychotics (SGAs); and 3) SGAs alone. We then stratified those on SGAs into two subgroups according to their prolactin-elevating properties: risperidone (RIS), paliperidone (PAL) or amisulpride (AMI) and all other SGAs. After adjusting for confounding factors, the risk of breast cancer in female schizophrenia patients was 1.94 higher than the non-schizophrenia cohort (aHR: 1.94, 95% CI: 1.43-2.63). Schizophrenia patients receiving a combination of FGAs and SGAs had a slightly higher risk of breast cancer than non-schizophrenic patients (aHR: 2.17, 95% CI: 1.56-3.01). Patients on RIS, PAL, and AMI had a 1.96-fold risk of breast cancer compared to the non-schizophrenic cohort (95% CI: 1.36-2.82). This study raises awareness among both clinicians and patients about the importance of breast cancer screening and the promotion of healthy lifestyle choices. Due to the nature of our database, confounding factors - such as parity, obesity, hormone therapy, and smoking - could not be controlled for. Copyright © 2017 Elsevier B.V. All rights reserved.

Different in the prospective association between individual plasma phospholipid saturated fatty acids and incident type 2 diabetes: the EPIC-InterAct case-cohort study

NARCIS (Netherlands)

Forouhi, N.G.; Koulman, A.; Sharp, S.J.; Groenendijk-van Woudenbergh, G.J.; Feskens, E.J.M.

2014-01-01

Background Conflicting evidence exists regarding the association between saturated fatty acids (SFAs) and type 2 diabetes. In this longitudinal case-cohort study, we aimed to investigate the prospective associations between objectively measured individual plasma phospholipid SFAs and incident type 2

Subsequent vitiligo after hematopoietic stem cell transplantation: A nationwide population-based cohort study from Korea.

Science.gov (United States)

Bae, Jung Min; Choi, Kwang Hyun; Jung, Han Mi; Kim, Sook Young; Kim, Miri; Kim, Gyung Moon; Yu, Dong Soo; Lee, Young Bok

2017-03-01

Subsequent vitiligo after hematopoietic stem cell transplantation (HSCT) has been described sporadically in case series. To investigate the incidence and risk factors of subsequent vitiligo after HSCT. A nationwide, population-based cohort study was performed using the Korean National Health Insurance Claims Database from 2009 to 2013. All HSCT recipients who had undergone HSCT between 2010 and 2011 and not treatment for vitiligo in 2009 (to exclude preexisting active vitiligo) were included in the HSCT recipient group, and an age- and sex-matched control group without HSCT was also established. A total of 2747 HSCT recipients and 8241 controls were enrolled. Newly acquired vitiligo occurred in 1.06% of HSCT recipients between 2010 and 2013, and there was a significant increase (OR 3.130, 95% CI 1.859-5.271) in cases of vitiligo in HSCT recipients compared with controls (0.34%). Allogeneic HSCT (OR 5.593, 95% CI 1.628-19.213) and bone marrow-sourced stem cells (as compared with peripheral blood-sourced stem cells; OR 2.492, 95% CI 1.114-5.576) were independently associated with the development of vitiligo after HSCT. Medical record review was not available. Vitiligo developed at a significantly increased rate after HSCT compared with controls. Allogeneic HSCT and bone marrow-sourced stem cells were independent risk factors. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Dialysis Modality and Readmission Following Hospital Discharge: A Population-Based Cohort Study.

Science.gov (United States)

Perl, Jeffrey; McArthur, Eric; Bell, Chaim; Garg, Amit X; Bargman, Joanne M; Chan, Christopher T; Harel, Shai; Li, Lihua; Jain, Arsh K; Nash, Danielle M; Harel, Ziv

2017-07-01

Readmissions following hospital discharge among maintenance dialysis patients are common, potentially modifiable, and costly. Compared with patients receiving in-center hemodialysis (HD), patients receiving peritoneal dialysis (PD) have fewer routine dialysis clinic encounters and as a result may be more susceptible to a hospital readmission following discharge. Population-based retrospective-cohort observational study. Patients treated with maintenance dialysis who were discharged following an acute-care hospitalization during January 1, 2003, to December 31, 2013, across 164 acute-care hospitals in Ontario, Canada. For those with multiple hospitalizations, we randomly selected a single hospitalization as the index hospitalization. Dialysis modality PD or in-center HD. Propensity scores were used to match each patient on PD therapy to 2 patients on in-center HD therapy to ensure that baseline indicators of health were similar between the 2 groups. All-cause 30-day readmission following the index hospital discharge. 28,026 dialysis patients were included in the study. 4,013 PD patients were matched to 8,026 in-center HD patients. Among the matched cohort, 30-day readmission rates were 7.1 (95% CI, 6.6-7.6) per 1,000 person-days for patients on PD therapy and 6.0 (95% CI, 5.7-6.3) per 1,000 person-days for patients on in-center HD therapy. The risk for a 30-day readmission among patients on PD therapy was higher compared with those on in-center HD therapy (adjusted HR, 1.19; 95% CI, 1.08-1.31). The primary results were consistent across several key prespecified subgroups. Lack of information for the frequency of nephrology physician encounters following discharge from the hospital in both the PD and in-center HD cohorts. Limited validation of International Classification of Diseases, Tenth Revision codes. The risk for 30-day readmission is higher for patients on home-based PD compared to in-center HD therapy. Interventions to improve transitions in care between the

Sociodemographic factors and vestibular schwannoma: a Danish nationwide cohort study

DEFF Research Database (Denmark)

Schüz, Joachim; Steding-Jessen, Marianne; Hansen, Søren

2010-01-01

Vestibular schwannoma (VS) (or acoustic neuroma) accounts for about 5%-6% of all intracranial tumors; little is known about the etiology. We investigated the association between various sociodemographic indicators and VS in a cohort of 3.26 million Danish residents, with 1087 cases identified in 35...... 308 974 person-years under risk, with data accrued from 1993 to 2006. Complete ascertainment of cases was ensured by using population-based and clinical cancer registries. Information on sociodemographic indicators was obtained on an annually updated individual level from Statistics Denmark. Log...

Birth order and mortality: a population-based cohort study.

Science.gov (United States)

Barclay, Kieron; Kolk, Martin

2015-04-01

This study uses Swedish population register data to investigate the relationship between birth order and mortality at ages 30 to 69 for Swedish cohorts born between 1938 and 1960, using a within-family comparison. The main analyses are conducted with discrete-time survival analysis using a within-family comparison, and the estimates are adjusted for age, mother's age at the time of birth, and cohort. Focusing on sibships ranging in size from two to six, we find that mortality risk in adulthood increases with later birth order. The results show that the relative effect of birth order is greater among women than among men. This pattern is consistent for all the major causes of death but is particularly pronounced for mortality attributable to cancers of the respiratory system and to external causes. Further analyses in which we adjust for adult socioeconomic status and adult educational attainment suggest that social pathways only mediate the relationship between birth order and mortality risk in adulthood to a limited degree.

Mortality study of civilian employees exposed to contaminated drinking water at USMC Base Camp Lejeune: a retrospective cohort study

Science.gov (United States)

2014-01-01

Background Two drinking water systems at U.S. Marine Corps Base Camp Lejeune, North Carolina were contaminated with solvents during 1950s-1985. Methods We conducted a retrospective cohort mortality study of 4,647 civilian, full-time workers employed at Camp Lejeune during 1973–1985 and potentially exposed to contaminated drinking water. We selected a comparison cohort of 4,690 Camp Pendleton workers employed during 1973–1985 and unexposed to contaminated drinking water. Mortality follow-up period was 1979-2008. Cause-specific standardized mortality ratios utilized U.S. age-, sex-, race-, and calendar period-specific mortality rates as reference. We used survival analysis to compare mortality rates between Camp Lejeune and Camp Pendleton workers and assess the effects of estimated cumulative contaminant exposures within the Camp Lejeune cohort. Ground water contaminant fate/transport and distribution system models provided monthly estimated contaminant levels in drinking water serving workplaces at Camp Lejeune. The confidence interval (CI) indicated precision of effect estimates. Results Compared to Camp Pendleton, Camp Lejeune workers had mortality hazard ratios (HRs) >1.50 for kidney cancer (HR = 1.92, 95% CI: 0.58, 6.34), leukemias (HR = 1.59, 95% CI: 0.66, 3.84), multiple myeloma (HR = 1.84, 95% CI: 0.45, 7.58), rectal cancer (HR = 1.65, 95% CI: 0.36, 7.44), oral cavity cancers (HR = 1.93, 95% CI: 0.34, 10.81), and Parkinson’s disease (HR = 3.13, 95% CI: 0.76, 12.81). Within the Camp Lejeune cohort, monotonic exposure-response relationships were observed for leukemia and vinyl chloride and PCE, with mortality HRs at the high exposure category of 1.72 (95% CI: 0.33, 8.83) and 1.82 (95% CI: 0.36, 9.32), respectively. Cumulative exposures were above the median for most deaths from cancers of the kidney, esophagus, rectum, prostate, and Parkinson’s disease, but small numbers precluded evaluation of exposure-response relationships. Conclusion The study found

The association between paternal and adolescent depressive symptoms: evidence from two population-based cohorts.

Science.gov (United States)

Lewis, Gemma; Neary, Martha; Polek, Ela; Flouri, Eirini; Lewis, Glyn

2017-12-01

Incidence of depression increases markedly around age 13 years, and nearly three-quarters of adults report that their mental health problems started in adolescence. Although maternal depression is a risk factor for adolescent depression, evidence about the association between paternal and adolescent depression is inconclusive, and many studies have methodological limitations. We aimed to assess the association between paternal and adolescent depressive symptoms in two large population-based cohort studies. We used data for two-parent families from two representative prospective cohorts in Ireland (Growing up in Ireland [GUI]) and the UK (Millennium Cohort Study [MCS]). Parental depressive symptoms were measured with the Centre for Epidemiological Studies Depression Scale in the GUI cohort when children were 9 years old, and the Kessler six-item psychological distress scale in the MCS cohort when children were 7 years old. Adolescent depressive symptoms were measured with the Short Mood and Feelings Questionnaire (SMFQ) at age 13 years in the GUI cohort and age 14 years in the MCS cohort. We analysed data using linear regression models, before and after adjustment for confounders, in both multiply imputed and complete case samples. There were 6070 families in GUI and 7768 in MCS. After all adjustments, a 1 SD (three-point) increase in paternal depressive symptoms was associated with an increase of 0·24 SMFQ points (95% CI 0·03-0·45; p=0·023) in the GUI cohort and 0·18 SMFQ points (0·01-0·36; p=0·041) in the MCS cohort. This association was independent of, and not different in magnitude to, the association between maternal and adolescent depressive symptoms (Wald test p=0·435 in the GUI cohort and 0·470 in the MCS cohort). Our results show an association between depressive symptoms in fathers and depressive symptoms in their adolescent offspring. These findings support the involvement of fathers as well as mothers in early interventions to reduce the

Exposure to sennoside-digoxin interaction and risk of digoxin toxicity: a population-based nested case-control study.

Science.gov (United States)

Wang, Meng-Ting; Li, I-Hsun; Lee, Wan-Ju; Huang, Tien-Yu; Leu, Hsin-Bang; Chan, Agnes L F

2011-11-01

Digoxin is an important medication for heart failure (HF) patients and sennosides are widely used to treat constipation. Recently, safety concerns have been raised about a possible interaction between sennosides and digoxin, an issue that has not been studied empirically. This study therefore aimed to evaluate whether exposure to sennoside-digoxin interaction is associated with an increased risk of digoxin toxicity. This was a population-based nested case-control study that analysed data obtained from the Taiwan National Health Insurance Research Database between 1 January 2001 and 31 December 2004. All HF patients treated with digoxin for the first time were included as the study cohort. Of these, cases were identified as subjects hospitalized for digoxin toxicity (International Classification of Diseases, Ninth Revision, Clinical Modification, ICD-9-CM 972.1), and matched to randomly selected controls. Use of sennosides was compared between the two groups. Odds ratios (ORs) were employed to quantify the risk associated with exposure to sennoside-digoxin interaction by conditional logistic regression. The study cohort comprised 222,527 HF patients, of whom 524 were identified as cases and 2,502 as matched controls. Use of sennosides during the 14 days preceding the index date was found to be associated with a 1.61-fold increased risk of digoxin toxicity [95% confidence interval (CI) = 1.15, 2.25]. Additionally, a greater risk was observed for sennosides prescribed at an average daily dose ≥ 24 mg (adjusted OR = 1.93; 95% CI = 1.27, 2.94). The combined use of sennosides and digoxin was found to be associated with a modest increased risk of digoxin toxicity in HF patients.

How to investigate and adjust for selection bias in cohort studies

DEFF Research Database (Denmark)

Nohr, Ellen A; Liew, Zeyan

2018-01-01

National Birth Cohort (DNBC) as examples on how to quantify selection bias and also understand the underlying selection mechanisms. Although women who chose to participate in the cohort were typically of higher social status, healthier and with less disease than all those eligible for study, differential...... of the presented methods are applicable even with limited data on non-participants and those lost to follow-up, and can also be applied to other study designs such as case-control studies and surveys. This article is protected by copyright. All rights reserved.......Longitudinal cohort studies can provide important evidence about preventable causes of disease, but the success relies heavily on the commitment of their participants, both at recruitment and during follow-up. Initial participation rates have decreased in recent decades as have willingness...

MR imaging of the brain in large cohort studies: feasibility report of the population- and patient-based BiDirect study

International Nuclear Information System (INIS)

Teuber, Anja; Berger, Klaus; Wersching, Heike; Sundermann, Benedikt; Kugel, Harald; Schwindt, Wolfram; Heindel, Walter; Minnerup, Jens; Dannlowski, Udo

2017-01-01

To describe the implementation and protocol of cerebral magnetic resonance imaging (MRI) in the longitudinal BiDirect study and to report rates of study participation as well as management of incidental findings. Data came from the BiDirect study that investigates the relationship between depression and arteriosclerosis and comprises 2258 participants in three cohorts: 999 patients with depression, 347 patients with manifest cardiovascular disease (CVD) and 912 population-based controls. The study program includes MRI of the brain. Reasons for non-participation were systematically collected. Incidental findings were categorized and disclosed according to clinical relevance. At baseline 2176 participants were offered MRI, of whom 1453 (67 %) completed it. Reasons for non-participation differed according to cohort, age and gender with controls showing the highest participation rate of 79 %. Patient cohorts had higher refusal rates and CVD patients a high prevalence of contraindications. In the first follow-up examination 69 % of participating subjects completed MRI. Incidental findings were disclosed to 246 participants (17 %). The majority of incidental findings were extensive white matter hyperintensities requiring further diagnostic work-up. Knowledge about subjects and sensible definition of incidental findings are crucial for large-scale imaging projects. Our data offer practical and concrete information for the design of future studies. (orig.)

MR imaging of the brain in large cohort studies: feasibility report of the population- and patient-based BiDirect study

Energy Technology Data Exchange (ETDEWEB)

Teuber, Anja; Berger, Klaus; Wersching, Heike [University of Muenster, Institute of Epidemiology and Social Medicine, Muenster (Germany); Sundermann, Benedikt; Kugel, Harald; Schwindt, Wolfram; Heindel, Walter [University Hospital Muenster, Department of Clinical Radiology, Muenster (Germany); Minnerup, Jens [University Hospital Muenster, Department of Neurology, Muenster (Germany); Dannlowski, Udo [University of Muenster, Department of Psychiatry, Muenster (Germany); University of Marburg, Department of Psychiatry, Marburg (Germany)

2017-01-15

To describe the implementation and protocol of cerebral magnetic resonance imaging (MRI) in the longitudinal BiDirect study and to report rates of study participation as well as management of incidental findings. Data came from the BiDirect study that investigates the relationship between depression and arteriosclerosis and comprises 2258 participants in three cohorts: 999 patients with depression, 347 patients with manifest cardiovascular disease (CVD) and 912 population-based controls. The study program includes MRI of the brain. Reasons for non-participation were systematically collected. Incidental findings were categorized and disclosed according to clinical relevance. At baseline 2176 participants were offered MRI, of whom 1453 (67 %) completed it. Reasons for non-participation differed according to cohort, age and gender with controls showing the highest participation rate of 79 %. Patient cohorts had higher refusal rates and CVD patients a high prevalence of contraindications. In the first follow-up examination 69 % of participating subjects completed MRI. Incidental findings were disclosed to 246 participants (17 %). The majority of incidental findings were extensive white matter hyperintensities requiring further diagnostic work-up. Knowledge about subjects and sensible definition of incidental findings are crucial for large-scale imaging projects. Our data offer practical and concrete information for the design of future studies. (orig.)

Nutritional rickets in Norway: a nationwide register-based cohort study.

Science.gov (United States)

Meyer, Haakon E; Skram, Kristina; Berge, Ingvill Almås; Madar, Ahmed A; Bjørndalen, Hilde Johanne

2017-05-29

Poor vitamin D status has been reported to be highly prevalent in many non-western immigrant groups living in Norway and other western countries. However, data on rickets are scarce, and the aim of the current study was to identify new cases of nutritional rickets in Norway in the period 2008-2012 among children under the age of 5 years. Register-based cohort study. The Norwegian population from 2008 to 2012. Children with nutritional rickets under the age of 5 years. Nutritional rickets. Patients with ICD10 (International Statistical Classification of Diseases and Related Health Problems, 10th revision) diagnosis code E55.0 (active rickets) treated at all Norwegian hospitals were identified in the Norwegian Patient Registry. We were able to review 85% of the medical records for diagnosis confirmation. In addition, we identified patients with the diagnoses E55.9, E64.3 and E83.3 to identify individuals with rickets who had been given other diagnoses. Nutritional rickets was confirmed in 39 children aged 0-4 years with the diagnosis of E55.0. In addition, three patients with the diagnosis of unspecified vitamin D deficiency (E55.9) were classified as having nutritional rickets, giving a total of 42 patients. Mean age at diagnosis was 1.40 years (range 0.1-3.5 years), and 93% had a non-western immigrant background. The incidence rate of rickets was estimated to be 0.3 per 10 000 person-years in the total Norwegian child population under the age of 5 years and 3.1 per 10 000 person-years in those with an immigrant background from Asia or Africa. The number of children with nutritional rickets in Norway remained low in the period 2008-2012. Nearly all children had a non-western immigrant background. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Interaction between interleukin-10 (IL-10 polymorphisms and dietary fibre in relation to risk of colorectal cancer in a Danish case-cohort study

Directory of Open Access Journals (Sweden)

Andersen Vibeke

2012-05-01

Full Text Available Abstract Background More than 50% of the colorectal cancer (CRC etiology has been attributed to diet. Established or suspected dietary factors modifying risk of CRC are red meat, cereals, fish, and fibre. Diet and lifestyle may be linked to cancer through inflammation. Interleukin-10 (IL-10 is an anti-inflammatory cytokine. We wanted to test if dietary factors and IL10 polymorphisms interact in relation to colorectal carcinogenesis. Methods The functional IL10 polymorphism C-592A (rs1800872 and the marker rs3024505 were assessed in relation to diet and lifestyle in a nested case-cohort study of 378 CRC cases and 775 randomly selected participants from a prospective study of 57,053 persons. Genotyping data on the IL10 polymorphism C-592A, smoking and non-steroidal anti-inflammatory drugs (NSAID was retrieved from Vogel et al. (Mutat Res, 2007; 624:88. Incidence rate ratios (IRR and 95% Confidence Interval (95% CI were calculated. Results No associations were found between the IL10 rs3024505 polymorphism and risk of CRC. There was interaction between rs3024505 and dietary fibre (P-value for interaction = 0.01. IL10 rs3024505 homozygous wildtype carriers were at 27% reduced risk of CRC per 10 g fibre per day (95% CI: 0.60-0.88 whereas variant carriers had no risk reduction by fibre intake. Also, interaction between IL10 C-592A and intake of fibre was found (P-value for interaction = 0.02. Among those eating IL10 polymorphisms and dietary meat, cereal, or fish intake, or between IL10 rs3024505 and smoking or NSAID use were found. Conclusions In this northern Caucasian cohort we found interaction between IL10 and dietary fibre in CRC carcinogenesis. High intake of fibre seems to protect against CRC among individuals with IL10 related genetic susceptibility to CRC. This finding should be evaluated in other prospective and population-based cohorts with different ethnic groups.

Family history of psychiatric illness as a risk factor for schizoaffective disorder: a Danish register-based cohort study

DEFF Research Database (Denmark)

Laursen, Thomas Munk; Labouriau, Rodrigo; Licht, Rasmus W

2005-01-01

BACKGROUND: Schizoaffective disorder may be related to both schizophrenia and bipolar disorders, but no population-based studies, to our knowledge, have investigated this association in families. OBJECTIVES: To determine whether a psychiatric history of schizoaffective disorder, bipolar disorder......, or schizophrenia among parents and siblings is a risk factor for developing a schizoaffective disorder, and whether a specific pattern of family history of psychiatric illness exists in persons with schizoaffective disorder compared with persons with bipolar disorder or schizophrenia. DESIGN: Register-based cohort...... study. SETTING: Denmark. COHORT: The 2.4 million persons born in Denmark after 1952. MAIN OUTCOME MEASURES: Relative risks of the 3 illnesses estimated by Poisson regression. RESULTS: In total, 1925 persons had a schizoaffective disorder, 3721 had a bipolar disorder, and 12 501 had schizophrenia...

Bipolar disorder and the risk of fracture: A nationwide population-based cohort study.

Science.gov (United States)

Su, Jian-An; Cheng, Bi-Hua; Huang, Yin-Cheng; Lee, Chuan-Pin; Yang, Yao-Hsu; Lu, Mong-Liang; Hsu, Chung-Yao; Lee, Yena; McIntyre, Roger S; Chin Lin, Tzu; Chin-Hung Chen, Vincent

2017-08-15

The co-primary aims are: 1) to compare the risk of fracture between adults with bipolar disorder and those without bipolar disorder; and 2) to assess whether lithium, anticonvulsants and antipsychotics reduce risk of fracture among individuals with bipolar disorder. The analysis herein is a population-based retrospective cohort study, utilizing the National Health Insurance (NHI) medical claims data collected between 1997 and 2013 in Taiwan. We identified 3705 cases with incident diagnoses of bipolar disorder during study period and 37,050 matched controls without bipolar diagnoses. Incident diagnosis of fracture was operationalized as any bone fracture after the diagnosis of bipolar disorder or after the matched index date for controls. Bipolar patients had significantly higher risk of facture when compared to matched controls (17.6% versus 11.7%, respectively pbipolar disorder and a prior history of psychiatric hospitalization were had higher risk for bone fracture than those without prior history of psychiatric hospitalization when compared to match controls. Higher cumulative dose of antipsychotics or mood stabilizers did not increase the risk of fracture. The diagnoses of bipolar disorder were not confirmed with structured clinical interview. Drug adherence, exact exposure dosage, smoking, lifestyle, nutrition and exercise habits were unable to be assessed in our dataset. Bipolar disorder is associated with increased risk of fracture, and higher cumulative dose of mood stabilizers and antipsychotics did not further increase the risk of fracture. Copyright © 2017 Elsevier B.V. All rights reserved.

Quantifying the dose-response relationship between circulating folate concentrations and colorectal cancer in cohort studies: a meta-analysis based on a flexible meta-regression model.

Science.gov (United States)

Chuang, Shu-Chun; Rota, Matteo; Gunter, Marc J; Zeleniuch-Jacquotte, Anne; Eussen, Simone J P M; Vollset, Stein Emil; Ueland, Per Magne; Norat, Teresa; Ziegler, Regina G; Vineis, Paolo

2013-10-01

Most epidemiologic studies on folate intake suggest that folate may be protective against colorectal cancer, but the results on circulating (plasma or serum) folate are mostly inconclusive. We conducted a meta-analysis of case-control studies nested within prospective studies on circulating folate and colorectal cancer risk by using flexible meta-regression models to test the linear and nonlinear dose-response relationships. A total of 8 publications (10 cohorts, representing 3,477 cases and 7,039 controls) were included in the meta-analysis. The linear and nonlinear models corresponded to relative risks of 0.96 (95% confidence interval (CI): 0.91, 1.02) and 0.99 (95% CI: 0.96, 1.02), respectively, per 10 nmol/L of circulating folate in contrast to the reference value. The pooled relative risks when comparing the highest with the lowest category were 0.80 (95% CI: 0.61, 0.99) for radioimmunoassay and 1.03 (95% CI: 0.83, 1.22) for microbiological assay. Overall, our analyses suggest a null association between circulating folate and colorectal cancer risk. The stronger association for the radioimmunoassay-based studies could reflect differences in cohorts and study designs rather than assay performance. Further investigations need to integrate more accurate measurements and flexible modeling to explore the effects of folate in the presence of genetic, lifestyle, dietary, and hormone-related factors.

Use of fertility drugs and risk of uterine cancer: results from a large Danish population-based cohort study

DEFF Research Database (Denmark)

Jensen, Allan; Sharif, Heidi; Kjaer, Susanne K

2009-01-01

and 1998. In a case-cohort study, rate ratios and 95% confidence intervals were used to assess the effects of 4 groups of fertility drugs on overall risk of uterine cancer after adjustment for potentially confounding factors. Through mid-2006, 83 uterine cancers were identified. Ever use of any fertility......Some epidemiologic studies have indicated that uterine cancer risk may be increased after use of fertility drugs. To further assess this association, the authors used data from a large cohort of 54,362 women diagnosed with infertility who were referred to Danish fertility clinics between 1965...... drug was not associated with uterine cancer risk (rate ratio (RR) = 1.10, 95% confidence interval (CI): 0.69, 1.76). However, ever use of gonadotropins (follicle-stimulating hormone and human menopausal gonadotropin) increased uterine cancer risk (RR = 2.21, 95% CI: 1.08, 4.50); the risk was primarily...

Cohort studies in health sciences librarianship.

Science.gov (United States)

Eldredge, Jonathan

2002-10-01

What are the key characteristics of the cohort study design and its varied applications, and how can this research design be utilized in health sciences librarianship? The health, social, behavioral, biological, library, earth, and management sciences literatures were used as sources. All fields except for health sciences librarianship were scanned topically for either well-known or diverse applications of the cohort design. The health sciences library literature available to the author principally for the years 1990 to 2000, supplemented by papers or posters presented at annual meetings of the Medical Library Association. A narrative review for the health, social, behavioral, biological, earth, and management sciences literatures and a systematic review for health sciences librarianship literature for the years 1990 to 2000, with three exceptions, were conducted. The author conducted principally a manual search of the health sciences librarianship literature for the years 1990 to 2000 as part of this systematic review. The cohort design has been applied to answer a wide array of theoretical or practical research questions in the health, social, behavioral, biological, and management sciences. Health sciences librarianship also offers several major applications of the cohort design. The cohort design has great potential for answering research questions in the field of health sciences librarianship, particularly evidence-based librarianship (EBL), although that potential has not been fully explored.

Representativeness of the LifeLines Cohort Study

NARCIS (Netherlands)

Klijs, B.; Scholtens, S.; Mandemakers, J.J.; Snieder, H.; Stolk, R.P.; Smidt, N.

2015-01-01

Background LifeLines is a large prospective population-based three generation cohort study in the north of the Netherlands. Different recruitment strategies were adopted: recruitment of an index population via general practitioners, subsequent inclusion of their family members, and online

The role of metformin and statins in the incidence of epithelial ovarian cancer in type 2 diabetes: a cohort and nested case-control study.

Science.gov (United States)

Urpilainen, E; Marttila, M; Hautakoski, A; Arffman, M; Sund, R; Ilanne-Parikka, P; Arima, R; Kangaskokko, J; Puistola, U; Läärä, E; Hinkula, M

2018-02-07

To obtain evidence of the effects of metformin and statins on the incidence of ovarian cancer in women with type 2 diabetes (T2D). A retrospective cohort study and nested case-control study. The data were obtained from a diabetes database (FinDM) combining information from several nationwide registers. A cohort of 137 643 women over 40 years old and diagnosed with T2D during 1996-2011 in Finland. In full cohort analysis Poisson regression was used to estimate the hazard ratios (HR) in relation to ever use of metformin, insulin other oral anti-diabetic medication or statins. In the nested case-control analysis 20 controls were matched to each case of ovarian cancer. Conditional logistic regression was used to estimate HRs in relation to medication use and cumulative use of different medications. The estimates were adjusted for age and duration of T2D. Incidence of ovarian cancer. In all, 303 women were diagnosed with ovarian cancer during the follow up. Compared with other forms of oral anti-diabetic medication, metformin (HR 1.02, 95% CI: 0.72-1.45) was not found to be associated with the incidence of ovarian cancer. Neither was there evidence for statins to affect the incidence (HR 0.99, 95% CI: 0.78-1.25). In nested case-control analysis the results were essentially similar. No evidence of an association between the use of metformin or statins and the incidence of ovarian cancer in women with T2D was found. No evidence found for metformin or statins reducing the incidence of ovarian cancer. © 2018 Royal College of Obstetricians and Gynaecologists.

VTE Risk assessment – a prognostic Model: BATER Cohort Study of young women

Directory of Open Access Journals (Sweden)

Schürmann Rolf

2005-04-01

Full Text Available Abstract Background Community-based cohort studies are not available that evaluated the predictive power of both clinical and genetic risk factors for venous thromboembolism (VTE. There is, however, clinical need to forecast the likelihood of future occurrence of VTE, at least qualitatively, to support decisions about intensity of diagnostic or preventive measures. Materials and methods A 10-year observation period of the Bavarian Thromboembolic Risk (BATER study, a cohort study of 4337 women (18–55 years, was used to develop a predictive model of VTE based on clinical and genetic variables at baseline (1993. The objective was to prepare a probabilistic scheme that discriminates women with virtually no VTE risk from those at higher levels of absolute VTE risk in the foreseeable future. A multivariate analysis determined which variables at baseline were the best predictors of a future VTE event, provided a ranking according to the predictive power, and permitted to design a simple graphic scheme to assess the individual VTE risk using five predictor variables. Results Thirty-four new confirmed VTEs occurred during the observation period of over 32,000 women-years (WYs. A model was developed mainly based on clinical information (personal history of previous VTE and family history of VTE, age, BMI and one composite genetic risk markers (combining Factor V Leiden and Prothrombin G20210A Mutation. Four levels of increasing VTE risk were arbitrarily defined to map the prevalence in the study population: No/low risk of VTE (61.3%, moderate risk (21.1%, high risk (6.0%, very high risk of future VTE (0.9%. In 10.6% of the population the risk assessment was not possible due to lacking VTE cases. The average incidence rates for VTE in these four levels were: 4.1, 12.3, 47.2, and 170.5 per 104 WYs for no, moderate, high, and very high risk, respectively. Conclusion Our prognostic tool – containing clinical information (and if available also genetic data

Leukemia and brain tumors in Norwegian railway workers, a nested case-control study.

Science.gov (United States)

Tynes, T; Jynge, H; Vistnes, A I

1994-04-01

In an attempt to assess whether exposure to electromagnetic fields on Norwegian railways induces brain tumors or leukemia, the authors conducted a nested case-control study of railway workers based on incident cases from the Cancer Registry of Norway in a cohort of 13,030 male Norwegian railway workers who had worked on either electric or non-electric railways. The cohort comprised railway line, outdoor station, and electricity workers. The case series comprised 39 men with brain tumors and 52 men with leukemia (follow-up, 1958-1990). Each case was matched on age with four or five controls selected from the same cohort. The exposure of each study subject to electric and magnetic fields was evaluated from cumulative exposure measures based on present measurements and historical data. Limited information on potential confounders such as creosote, solvents, and herbicides was also collected; information on whether the subject had smoked was obtained by interviews with the subjects or work colleagues. The case-control analysis showed that men employed on electric railways, compared with non-electric ones, had an odds ratio for leukemia of 0.70 (adjusted for smoking) and an odds ratio for brain tumor of 0.87. No significant trend was shown for exposure to either magnetic or electric fields. These results do not support an association between exposure to 16 2/3-Hertz electric or magnetic fields and the risk for leukemia or brain tumors.

Chocolate consumption and risk of atrial fibrillation: Two cohort studies and a meta-analysis.

Science.gov (United States)

Larsson, Susanna C; Drca, Nikola; Jensen-Urstad, Mats; Wolk, Alicja

2018-01-01

Chocolate consumption has been inconsistently associated with risk of atrial fibrillation (AF). We investigated the association between chocolate consumption and risk of AF in Swedish adults from two cohort studies and conducted a meta-analysis to summarize available evidence from cohort studies on this topic. Our study population comprised 40,009 men from the Cohort of Swedish Men and 32,486 women from the Swedish Mammography Cohort. Incident AF cases were ascertained through linkage with the Swedish National Patient Register. Published cohort studies of chocolate consumption in relation to risk of AF were identified by a PubMed search through September 14, 2017. During a mean follow-up of 14.6 years, AF was diagnosed in 9978 Swedish men and women. Compared with non-consumers, the multivariable hazard ratio of AF for those in the highest category of chocolate consumption (≥3-4 servings/week) was 0.96 (95% CI 0.88-1.04). In a random-effects meta-analysis of 5 cohort studies, including 180,454 participants and 16,356 AF cases, the hazard ratios of AF were 0.97 (95% CI 0.94-1.01) per 2 servings/week increase in chocolate consumption and 0.96 (95% CI 0.90-1.03) for the highest versus lowest category of chocolate consumption. Available data provide no evidence of an association of chocolate consumption with risk of AF. Copyright © 2017 Elsevier Inc. All rights reserved.

Risk of Prostate Cancer after Trans Urethral Resection of BPH: A Cohort and Nested Case-Control Study

Directory of Open Access Journals (Sweden)

Beatrice Melin

2011-11-01

Full Text Available Epidemiological and experimental evidence suggests that inflammation plays a role in both prostate cancer (PCa and benign prostate hyperplasia (BPH. This study evaluates the risk of PC after transurethral resection (TURP for BPH and estimates the PCa risk related to presence of inflammation in the resected material. The Pathology Department at the University Hospital of Umeå (Umeå, Sweden identified BPH cases (n = 7,901 that underwent TURP between 1982 and 1997. Using these pathological specimens, we compared the incidence of PCa in the cohort to the population and calculated the standardized incidence and mortality ratios (SIR and SMR. Inflammation, the androgen receptor (AR, and p53 were evaluated in a nested case-control study of 201 cases and controls. Inflammation was graded severe or mild-moderate. In the follow-up period after TURP, cases developed prostate cancer and the controls did not. After TURP, SIR for prostate cancer increased [1.26, CI 95% (1.17–1.35], whereas SMR decreased [0.59, CI 95% (0.47–0.73]. Presence of inflammation at the time of TURP did not differ between cases and controls nor were there differences in p53 or AR staining. The data suggest a small increased risk of PCa after TURP and decreased PCa mortality. Inflammation at the time of TURP is not associated with PCa risk in this material. The increased PCa risk may be attributed to increased surveillance and PSA screening.

Risk of Prostate Cancer after Trans Urethral Resection of BPH: A Cohort and Nested Case-Control Study

International Nuclear Information System (INIS)

Karlsson, Camilla T.; Wiklund, Fredrik; Grönberg, Henrik; Bergh, Anders; Melin, Beatrice

2011-01-01

Epidemiological and experimental evidence suggests that inflammation plays a role in both prostate cancer (PCa) and benign prostate hyperplasia (BPH). This study evaluates the risk of PC after transurethral resection (TURP) for BPH and estimates the PCa risk related to presence of inflammation in the resected material. The Pathology Department at the University Hospital of Umeå (Umeå, Sweden) identified BPH cases (n = 7,901) that underwent TURP between 1982 and 1997. Using these pathological specimens, we compared the incidence of PCa in the cohort to the population and calculated the standardized incidence and mortality ratios (SIR and SMR). Inflammation, the androgen receptor (AR), and p53 were evaluated in a nested case-control study of 201 cases and controls. Inflammation was graded severe or mild-moderate. In the follow-up period after TURP, cases developed prostate cancer and the controls did not. After TURP, SIR for prostate cancer increased [1.26, CI 95% (1.17–1.35) ], whereas SMR decreased [0.59, CI 95% (0.47–0.73) ]. Presence of inflammation at the time of TURP did not differ between cases and controls nor were there differences in p53 or AR staining. The data suggest a small increased risk of PCa after TURP and decreased PCa mortality. Inflammation at the time of TURP is not associated with PCa risk in this material. The increased PCa risk may be attributed to increased surveillance and PSA screening

Risk of Prostate Cancer after Trans Urethral Resection of BPH: A Cohort and Nested Case-Control Study

Energy Technology Data Exchange (ETDEWEB)

Karlsson, Camilla T., E-mail: Camilla.thellenberg@onkologi.umu.se [Department of Radiation Sciences, Oncology, Umeå University, SE-901 87 Umeå (Sweden); Wiklund, Fredrik; Grönberg, Henrik [Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm SE-171 77 (Sweden); Bergh, Anders [Department of Medical Biosciences, Pathology, Umeå University, SE-901 87 Umeå (Sweden); Melin, Beatrice [Department of Radiation Sciences, Oncology, Umeå University, SE-901 87 Umeå (Sweden)

2011-11-08

Epidemiological and experimental evidence suggests that inflammation plays a role in both prostate cancer (PCa) and benign prostate hyperplasia (BPH). This study evaluates the risk of PC after transurethral resection (TURP) for BPH and estimates the PCa risk related to presence of inflammation in the resected material. The Pathology Department at the University Hospital of Umeå (Umeå, Sweden) identified BPH cases (n = 7,901) that underwent TURP between 1982 and 1997. Using these pathological specimens, we compared the incidence of PCa in the cohort to the population and calculated the standardized incidence and mortality ratios (SIR and SMR). Inflammation, the androgen receptor (AR), and p53 were evaluated in a nested case-control study of 201 cases and controls. Inflammation was graded severe or mild-moderate. In the follow-up period after TURP, cases developed prostate cancer and the controls did not. After TURP, SIR for prostate cancer increased [1.26, CI 95% (1.17–1.35) ], whereas SMR decreased [0.59, CI 95% (0.47–0.73) ]. Presence of inflammation at the time of TURP did not differ between cases and controls nor were there differences in p53 or AR staining. The data suggest a small increased risk of PCa after TURP and decreased PCa mortality. Inflammation at the time of TURP is not associated with PCa risk in this material. The increased PCa risk may be attributed to increased surveillance and PSA screening.

Incidence of non-lung solid cancers in Czech uranium miners: a case-cohort study.

Science.gov (United States)

Kulich, M; Reřicha, V; Reřicha, R; Shore, D L; Sandler, D P

2011-04-01

Uranium miners are chronically exposed to radon and its progeny, which are known to cause lung cancer and may be associated with leukemia. This study was undertaken to evaluate risk of non-lung solid cancers among uranium miners in Příbram region, Czech Republic. A retrospective stratified case-cohort study in a cohort of 22,816 underground miners who were employed between 1949 and 1975. All incident non-lung solid cancers were ascertained among miners who worked underground for at least 12 months (n=1020). A subcohort of 1707 subjects was randomly drawn from the same population by random sampling stratified on age. The follow-up period lasted from 1977 to 1996. Relative risks comparing 180 WLM (90th percentile) of cumulative lifetime radon exposure to 3 WLM (10th percentile) were 0.88 for all non-lung solid cancers combined (95% CI 0.73-1.04, n=1020), 0.87 for all digestive cancers (95% CI 0.69-1.09, n=561), 2.39 for gallbladder cancer (95% CI 0.52-10.98, n=13), 0.79 for larynx cancer (95% CI 0.38-1.64, n=62), 2.92 for malignant melanoma (95% CI 0.91-9.42, n=23), 0.84 for bladder cancer (95% CI 0.43-1.65, n=73), and 1.13 for kidney cancer (95% CI 0.62-2.04, n=66). No cancer type was significantly associated with radon exposure; only malignant melanoma and gallbladder cancer showed elevated but non-significant association with radon. Radon was not significantly associated with incidence of any cancer of interest, although a positive association of radon with malignant melanoma and gallbladder cancer cannot be entirely ruled out. Copyright © 2011 Elsevier Inc. All rights reserved.

Maternal thyroid disorder in pregnancy and risk of cerebral palsy in the child: a population-based cohort study.

Science.gov (United States)

Petersen, Tanja Gram; Andersen, Anne-Marie Nybo; Uldall, Peter; Paneth, Nigel; Feldt-Rasmussen, Ulla; Tollånes, Mette Christophersen; Strandberg-Larsen, Katrine

2018-05-31

Cerebral palsy is the most frequent motor disability in childhood, but little is known about its etiology. It has been suggested that cerebral palsy risk may be increased by prenatal thyroid hormone disturbances. The objective of this study was to investigate whether maternal thyroid disorder is associated with increased risk of cerebral palsy. A population-based cohort study using two study populations. 1) 1,270,079 children born in Denmark 1979-2007 identified in nationwide registers, and 2) 192,918 children born 1996-2009 recruited into the Danish National Birth Cohort and The Norwegian Mother and Child Cohort study, combined in the MOthers and BAbies in Norway and Denmark (MOBAND) collaboration cohort. Register-based and self-reported information on maternal thyroid disorder was studied in relation to risk of cerebral palsy and its unilateral and bilateral spastic subtypes using multiple logistic regression. Children were followed from the age of 1 year to the age of 6 years, and cerebral palsy was identified in nationwide registers with verified diagnoses. In register data, hypothyroidism was recognized in 12,929 (1.0%), hyperthyroidism in 9943 (0.8%), and unclassifiable thyroid disorder in 753 (cerebral palsy was 1.0 (95% CI: 0.7-1.5). Maternal thyroid disorder identified during pregnancy was associated with elevated risk of unilateral spastic cerebral palsy (odds ratio 3.1 (95% CI: 1.2-8.4)). In MOBAND, 3042 (1.6%) of the mothers reported a thyroid disorder in pregnancy, which was not associated with cerebral palsy overall (odds ratio 1.2 (95% CI: 0.6-2.4)). Maternal thyroid disorder overall was not related to bilateral spastic cerebral palsy, but maternal thyroid disorder identified in pregnancy was associated with increased risk of unilateral spastic cerebral palsy. These findings should be replicated in studies making use of maternal blood samples.

Determinants of neonatal mortality in rural Northern Ethiopia: A population based nested case control study.

Directory of Open Access Journals (Sweden)

Robel Yirgu

Full Text Available In low income and middle income countries, neonatal mortality remains high despite the gradual reduction in under five mortality. Newborn death contributes for about 38% of all under five deaths. This study has identified the magnitude and independent predictors of neonatal mortality in rural Ethiopia.This population based nested case control study was conducted in rural West Gojam zone, Northern Ethiopia, among a cohort of pregnant women who gave birth between March 2011 and Feb 2012. The cohort was established by Maternal and Newborn Health in Ethiopia Partnership (MaNHEP project in 2010 by recruiting mothers in their third trimester, as identified by trained community volunteers. Once identified, women stayed in the cohort throughout their pregnancy period receiving Community Maternal and Newborn Health (CMNH training by health extension workers and community volunteers till the end of the first 48 hours postpartum. Cases were 75 mothers who lost their newborns to neonatal death and controls were 150 randomly selected mothers with neonates who survived the neonatal period. Data to identify cause of death were collected using the WHO standard verbal autopsy questionnaire after the culturally appropriate 40 days of bereavement period. Binomial logistic regression model was used to identify independent contributors to neonatal mortality.The neonatal mortality rate was AOR(95%CI = 18.6 (14.8, 23.2 per 1000 live births. Neonatal mortality declined with an increase in family size, neonates who were born among a family of more than two had lesser odds of death in the neonatal period than those who were born in a family of two AOR (95% CI = 0.13 (0.02, 0.71. Mothers who gave birth to 2-4 AOR(95%CI = 0.15 (0.05, 0.48 and 5+ children AOR(95%CI = 0.08 (0.02, 0.26 had lesser odds of losing their newborns to neonatal mortality. Previous history of losing a newborn to neonatal death also increased the odds of neonatal mortality during the last birth AOR

Open Access in Higher Education–Strategies for Engaging Diverse Student Cohorts

OpenAIRE

Signor, Luisa; Moore, Catherine

2014-01-01

With growth in online education, students gain tertiary qualifications through a mode more suited to their demographics such as work and life balance, learning styles and geographical accessibility. Inevitably this has led to a growth in diversity within student cohorts.The case study described in this paper illustrates strategies based on informed learning design for educating diverse student cohorts in an online program offered by Swinburne University of Technology. The case, an open-access...

Validation of the German Diabetes Risk Score within a population-based representative cohort.

Science.gov (United States)

Hartwig, S; Kuss, O; Tiller, D; Greiser, K H; Schulze, M B; Dierkes, J; Werdan, K; Haerting, J; Kluttig, A

2013-09-01

To validate the German Diabetes Risk Score within the population-based cohort of the Cardiovascular Disease - Living and Ageing in Halle (CARLA) study. The sample included 582 women and 719 men, aged 45-83 years, who did not have diabetes at baseline. The individual risk of every participant was calculated using the German Diabetes Risk Score, which was modified for 4 years of follow-up. Predicted probabilities and observed outcomes were compared using Hosmer-Lemeshow goodness-of-fit tests and receiver-operator characteristic analyses. Changes in prediction power were investigated by expanding the German Diabetes Risk Score to include metabolic variables and by subgroup analyses. We found 58 cases of incident diabetes. The median 4-year probability of developing diabetes based on the German Diabetes Risk Score was 6.5%. The observed and predicted probabilities of developing diabetes were similar, although estimation was imprecise owing to the small number of cases, and the Hosmer-Lemeshow test returned a poor correlation (chi-squared = 55.3; P = 5.8*10⁻¹²). The area under the receiver-operator characteristic curve (AUC) was 0.70 (95% CI 0.64-0.77), and after excluding participants ≥66 years old, the AUC increased to 0.77 (95% CI 0.70-0.84). Consideration of glycaemic diagnostic variables, in addition to self-reported diabetes, reduced the AUC to 0.65 (95% CI 0.58-0.71). A new model that included the German Diabetes Risk Score and blood glucose concentration (AUC 0.81; 95% CI 0.76-0.86) or HbA(1c) concentration (AUC 0.84; 95% CI 0.80-0.91) was found to peform better. Application of the German Diabetes Risk Score in the CARLA cohort did not reproduce the findings in the European Prospective Investigation into Cancer and Nutrition (EPIC) Potsdam study, which may be explained by cohort differences and model overfit in the latter; however, a high score does provide an indication of increased risk of diabetes. © 2013 The Authors. Diabetic Medicine © 2013 Diabetes

Vegetarianism, low meat consumption and the risk of colorectal cancer in a population based cohort study

NARCIS (Netherlands)

Gilsing, A.M.J.; Schouten, L.J.; Goldbohm, R.A.; Dagnelie, P.C.; Brandt, P.A. van den; Weijenberg, M.P.

2015-01-01

To study how a vegetarian or low meat diet influences the risk of colorectal cancer compared to a high meat diet, and to assess the explanatory role of factors associated with these diets. In the Netherlands Cohort Study – Meat Investigation Cohort (NLCS-MIC) (cohort of 10,210 individuals including

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors’ Offspring

Directory of Open Access Journals (Sweden)

Kotaro Ozasa

2018-04-01

Full Text Available Cohorts of atomic bomb survivors—including those exposed in utero—and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors’ children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young.

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors' Offspring.

Science.gov (United States)

Ozasa, Kotaro; Grant, Eric J; Kodama, Kazunori

2018-04-05

Cohorts of atomic bomb survivors-including those exposed in utero-and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors' children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young.

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors’ Offspring

Science.gov (United States)

Grant, Eric J; Kodama, Kazunori

2018-01-01

Cohorts of atomic bomb survivors—including those exposed in utero—and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors’ children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young. PMID:29553058

No Association between HMOX1 and Risk of Colorectal Cancer and No Interaction with Diet and Lifestyle Factors in a Prospective Danish Case-Cohort Study

Directory of Open Access Journals (Sweden)

Vibeke Andersen

2015-01-01

Full Text Available Red meat is a risk factor for colorectal cancer (CRC. We wanted to evaluate whether a functional polymorphism in the HMOX1 gene encoding heme oxygenase modifies risk of CRC or interacts with diet or lifestyle factors because this would identify heme or heme iron as a risk factor of CRC. The HMOX1 A-413T (rs2071746 was assessed in relation to risk of colorectal cancer (CRC and interactions with diet (red meat, fish, fiber, cereals, fruit and vegetables and lifestyle (use of non-steroidal anti-inflammatory drug and smoking status were assessed in a case-cohort study of 928 CRC cases and a comparison group of 1726 randomly selected participants from a prospective study of 57,053 persons. No association between HMOX1 A-413T and CRC risk was found (TT vs. AA + TA; IRR = 1.15, 95% CI: 0.98–1.36, p = 0.10 for the adjusted estimate. No interactions were found between diet or lifestyle and HMOX1 A-413T. HMOX1 A-413T was not associated with CRC risk and no interactions with diet or lifestyle were identified in this large, prospective cohort with high meat intake. The results reproduced the previous findings from the same cohort and did not support a link between heme or heme iron and colorectal cancer. These results should be sought and replicated in other well-characterized cohorts with high meat intake.

Association of Genetic Risk for Schizophrenia With Nonparticipation Over Time in a Population-Based Cohort Study.

Science.gov (United States)

Martin, Joanna; Tilling, Kate; Hubbard, Leon; Stergiakouli, Evie; Thapar, Anita; Davey Smith, George; O'Donovan, Michael C; Zammit, Stanley

2016-06-15

Progress has recently been made in understanding the genetic basis of schizophrenia and other psychiatric disorders. Longitudinal studies are complicated by participant dropout, which could be related to the presence of psychiatric problems and associated genetic risk. We tested whether common genetic variants implicated in schizophrenia were associated with study nonparticipation among 7,867 children and 7,850 mothers from the Avon Longitudinal Study of Parents and Children (ALSPAC; 1991-2007), a longitudinal population cohort study. Higher polygenic risk scores for schizophrenia were consistently associated with noncompletion of questionnaires by study mothers and children and nonattendance at data collection throughout childhood and adolescence (ages 1-15 years). These associations persisted after adjustment for other potential correlates of nonparticipation. Results suggest that persons at higher genetic risk for schizophrenia are likely to be underrepresented in cohort studies, which will underestimate risk of this and related psychiatric, cognitive, and behavioral phenotypes in the population. Statistical power to detect associations with these phenotypes will be reduced, while analyses of schizophrenia-related phenotypes as outcomes may be biased by the nonrandom missingness of these phenotypes, even if multiple imputation is used. Similarly, in complete-case analyses, collider bias may affect associations between genetic risk and other factors associated with missingness. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

The WISTAH hand study: A prospective cohort study of distal upper extremity musculoskeletal disorders

Directory of Open Access Journals (Sweden)

Garg Arun

2012-06-01

Full Text Available Abstract Background Few prospective cohort studies of distal upper extremity musculoskeletal disorders have been performed. Past studies have provided somewhat conflicting evidence for occupational risk factors and have largely reported data without adjustments for many personal and psychosocial factors. Methods/design A multi-center prospective cohort study was incepted to quantify risk factors for distal upper extremity musculoskeletal disorders and potentially develop improved methods for analyzing jobs. Disorders to analyze included carpal tunnel syndrome, lateral epicondylalgia, medial epicondylalgia, trigger digit, deQuervain’s stenosing tenosynovitis and other tendinoses. Workers have thus far been enrolled from 17 different employment settings in 3 diverse US states and performed widely varying work. At baseline, workers undergo laptop administered questionnaires, structured interviews, two standardized physical examinations and nerve conduction studies to ascertain demographic, medical history, psychosocial factors and current musculoskeletal disorders. All workers’ jobs are individually measured for physical factors and are videotaped. Workers are followed monthly for the development of musculoskeletal disorders. Repeat nerve conduction studies are performed for those with symptoms of tingling and numbness in the prior six months. Changes in jobs necessitate re-measure and re-videotaping of job physical factors. Case definitions have been established. Point prevalence of carpal tunnel syndrome is a combination of paraesthesias in at least two median nerve-served digits plus an abnormal nerve conduction study at baseline. The lifetime cumulative incidence of carpal tunnel syndrome will also include those with a past history of carpal tunnel syndrome. Incident cases will exclude those with either a past history or prevalent cases at baseline. Statistical methods planned include survival analyses and logistic regression. Discussion A

Higher risk of developing a subsequent migraine in adults with nonapnea sleep disorders: A nationwide population-based cohort study.

Science.gov (United States)

Harnod, Tomor; Wang, Yu-Chiao; Kao, Chia-Hung

2015-05-01

This nationwide population-based cohort study evaluated the effect of nonapnea sleep disorders (NSDs) on the subsequent development of a migraine. We identified 46,777 patients aged 20 years and older who were diagnosed with an NSD (ICD-9-CM: 307.4 or 780.5) and without coding for apnea-sleep disorders (ICD-9-CM: 780.51, 780.53, or 780.57) between 2000 and 2002 as the sleep disorder (SD) cohort. A comparison cohort of 93,552 people was enrolled. We calculated the adjusted hazard ratio (aHR) for developing a migraine (ICD-9-CM: 346) after adjusting for age, sex, comorbidity, and drug use. A Kaplan-Meier analysis was used to measure the cumulative incidence of a migraine between 2 curves until the end of 2011. The cumulative incidence of a migraine was significantly higher in the SD cohort. The aHR for developing a migraine in the SD cohort was 3.52 (95% CI=3.28-3.79). The risk of developing a migraine with an NSD was higher in men (aHR=4.31) than in women (aHR=3.35). The age-stratified effect of an NSD on developing a migraine was highest among patients aged 55 years and younger. Higher risks of developing a migraine were observed among the participants without any comorbidity and without any drug treatment for their insomnia. The findings of this population-based cohort study indicate a higher risk of developing a subsequent migraine in patients with an NSD, which could be considered an independent, predisposing factor for developing subsequent a migraine in adulthood. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Application of Probabilistic Multiple-Bias Analyses to a Cohort- and a Case-Control Study on the Association between Pandemrix™ and Narcolepsy.

Directory of Open Access Journals (Sweden)

Kaatje Bollaerts

Full Text Available An increase in narcolepsy cases was observed in Finland and Sweden towards the end of the 2009 H1N1 influenza pandemic. Preliminary observational studies suggested a temporal link with the pandemic influenza vaccine Pandemrix™, leading to a number of additional studies across Europe. Given the public health urgency, these studies used readily available retrospective data from various sources. The potential for bias in such settings was generally acknowledged. Although generally advocated by key opinion leaders and international health authorities, no systematic quantitative assessment of the potential joint impact of biases was undertaken in any of these studies.We applied bias-level multiple-bias analyses to two of the published narcolepsy studies: a pediatric cohort study from Finland and a case-control study from France. In particular, we developed Monte Carlo simulation models to evaluate a potential cascade of biases, including confounding by age, by indication and by natural H1N1 infection, selection bias, disease- and exposure misclassification. All bias parameters were evidence-based to the extent possible.Given the assumptions used for confounding, selection bias and misclassification, the Finnish rate ratio of 13.78 (95% CI: 5.72-28.11 reduced to a median value of 6.06 (2.5th- 97.5th percentile: 2.49-15.1 and the French odds ratio of 5.43 (95% CI: 2.6-10.08 to 1.85 (2.5th-97.5th percentile: 0.85-4.08.We illustrate multiple-bias analyses using two studies on the Pandemrix™-narcolepsy association and advocate their use to better understand the robustness of study findings. Based on our multiple-bias models, the observed Pandemrix™-narcolepsy association consistently persists in the Finnish study. For the French study, the results of our multiple-bias models were inconclusive.

Trend of Cardio-Metabolic Risk Factors in Polycystic Ovary Syndrome: A Population-Based Prospective Cohort Study

OpenAIRE

Ramezani Tehrani, Fahimeh; Montazeri, Seyed Ali; Hosseinpanah, Farhad; Cheraghi, Leila; Erfani, Hadi; Tohidi, Maryam; Azizi, Fereidoun

2015-01-01

Objective To see the changes of cardio-metabolic risk factors overtime in polycystic ovary syndrome vs. control women. Methods This study was conducted on 637 participants (85 PCOS and 552 control reproductive aged, 18–45 years) of Tehran Lipid and Glucose Study (TLGS), an ongoing population-based cohort study with 12 years of follow-up. The cardiovascular risk factors of these groups were assessed in three-year intervals using standard questionnaires, history taking, anthropometric measures,...

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study.

Science.gov (United States)

López Gómez, María Andrée; Durán, Xavier; Zaballa, Elena; Sanchez-Niubo, Albert; Delclos, George L; Benavides, Fernando G

2016-03-07

The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and death. The WORKss cohort originated from the Continuous Working Life Sample (CWLS) generated by the General Directorate for the Organization of the Social Security in Spain. The CWLS contains a 4% representative sample of all individuals in contact with the Social Security system. The WORKss cohort exclusively includes individuals with a labour trajectory from 1981 or later. In 2004, the cohort was initiated with 1,022 ,79 Social Security members: 840,770 (82.2%) contributors and 182,009 (17.8%) beneficiaries aged 16 and older. The WORKss cohort includes demographic characteristics, chronological data about employment history, retirement, permanent disability and death. These data make possible the measurement of incidence of permanent disability, the number of potential years of working life lost, and the number of contracts and inactive periods with the Social Security system. The WORKss cohort was linked to temporary sickness absence registries to study medical diagnoses that lead to permanent disability and consequently to an earlier exit from the labour market in unhealthy conditions. Thanks to its administrative source, the WORKss cohort study will continue follow-up in the coming years, keeping the representativeness of the Spanish population affiliated to the Social Security system. The linkage between the WORKss cohort and temporary sickness absence registries is envisioned to continue. Future plans include the linkage of the cohort with mortality registries. Published by the BMJ

Oxytocin during labour and risk of severe postpartum haemorrhage: a population-based, cohort-nested case–control study

Science.gov (United States)

Belghiti, Jérémie; Kayem, Gilles; Dupont, Corinne; Rudigoz, René-Charles; Bouvier-Colle, Marie-Hélène

2011-01-01

Objectives Postpartum haemorrhage (PPH) is a major cause of maternal mortality and morbidity worldwide. Experimental studies support the hypothesis that oxytocin administration during labour, a common although not evidence-based practice, may increase the risk of atonic PPH. The clinical studies, however, are inconclusive. The objectives of this study was to investigate the association between the level of oxytocin exposure during labour and the risk of severe PPH and to explore whether the prophylactic use of oxytocin after birth modifies this association. Design Population-based, cohort-nested case–control study. Setting 106 French hospitals from December 2004 through November 2006. Participants Women with term singleton vaginal deliveries, after an uncomplicated pregnancy. Cases were 1483 women with severe PPH, defined by peripartum change in haemoglobin of ≥4 g/dl or need for blood transfusion. Controls were 1758 women from a random sample of parturients without PPH. Main outcome measures The independent association between the level of oxytocin during labour and the risk of severe PPH was tested and quantified with ORs through two-level multivariable logistic regression modelling. Results Oxytocin was administered during labour to 73% of cases and 61% of controls (crude OR: 1.7, 95% CI 1.5 to 2.0). After adjustment for all potential confounders, oxytocin during labour was associated with a significantly higher risk of severe PPH (adjusted OR: 1.8, 95% CI 1.3 to 2.6) in women who did not receive prophylactic oxytocin after delivery; the OR for haemorrhage increased from 1 to 5 according to the level of oxytocin exposure. In women who had prophylactic oxytocin after delivery, this association was significant only for the highest exposure categories. Conclusions Oxytocin during labour appears to be an independent risk factor for severe PPH. The results emphasise the need for guidelines clarifying the evidence-based indications for this procedure and the

Intrauterine exposure to carbamazepine and specific congenital malformations : systematic review and case-control study

NARCIS (Netherlands)

Jentink, Janneke; Dolk, Helen; Loane, Maria A.; Morris, Joan K.; Wellesley, Diana; Garne, Ester; de Jong-van den Berg, Lolkje

2010-01-01

Objective To identify specific major congenital malformations associated with use of carbamazepine in the first trimester of pregnancy. Design A review of all published cohort studies to identify key indications and a population based case-control study to test these indications. Setting Review of

Do antidepressants increase the risk of mania and bipolar disorder in people with depression? A retrospective electronic case register cohort study

OpenAIRE

Patel, Rashmi; Reiss, Peter; Shetty, Hitesh; Broadbent, Matthew; Stewart, Robert; McGuire, Philip; Taylor, Matthew

2015-01-01

Objectives To investigate the association between antidepressant therapy and the later onset of mania/bipolar disorder.Design Retrospective cohort study using an anonymised electronic health record case register.Setting South London and Maudsley National Health Service (NHS) Trust (SLaM), a large provider of inpatient and community mental healthcare in the UK.Participants 21 012 adults presenting to SLaM between 1 April 2006 and 31 March 2013 with unipolar depression.Exposure Prior antidepres...

Necrotizing Fasciitis Among Patients With Liver Cirrhosis in Texas, 2001 - 2010: A Population-Based Cohort Study.

Science.gov (United States)

Oud, Lavi; Watkins, Phillip

2016-02-01

Liver cirrhosis is a risk factor for necrotizing fasciitis (NF), and is associated with markedly worse outcomes than for NF among non-cirrhosis patients. Only limited, mostly single-center, data were reported to date on the epidemiology, clinical features, resource utilization and outcomes of NF among patients with cirrhosis. We studied a population-based cohort of adult hospitalizations associated with cirrhosis, who had a diagnosis of NF during the years 2001 - 2010, using the Texas Inpatient Public Use Data File. The annual volume of NF hospitalizations was benchmarked against all annual hospitalizations with a diagnosis of cirrhosis. The patterns of demographics, chronic comorbidities, evolving organ failure, resource utilization and outcomes were examined. There were 371,745 hospitalizations associated with liver cirrhosis, with 381 NF hospitalizations during study period. The annual volume of NF hospitalizations rose 7.9%/year (P = 0.0287), while its incidence among cirrhosis-associated hospitalizations remained unchanged (P = 0.2955). Non-cirrhosis comorbidities were reported in 69.6% and ICU care was required in 67.2% of NF hospitalization. The key changes noted between 2001 - 2003 and 2008 - 2010 among NF hospitalizations included rising mean (SD) Deyo-Charlson index 2.4 (1.5) vs. 3.9 (2.4) (P < 0.0001), development of ≥ 3 organ failures in 9.1% vs. 39.8% (P < 0.0001), and discharge to long-term care facilities 7.8% vs. 21.1% (P = 0.0204). Hospital mortality was unchanged (26% vs. 33.1%; P = 0.3659). Inflation-adjusted total hospital charges did not change (P = 0.1025) during study period. The present cohort of NF associated with liver cirrhosis is the largest reported to date. A rising annual volume of NF events matched a corresponding increase in cirrhosis-associated hospitalizations. There was increasing burden of chronic comorbidity and rising severity of illness, with a majority of patients requiring ICU care. Case fatality was high and there has

The Premenopausal Breast Cancer Collaboration: A pooling project of studies participating in the National Cancer Institute Cohort Consortium

Science.gov (United States)

Nichols, Hazel B.; Schoemaker, Minouk J.; Wright, Lauren B.; McGowan, Craig; Brook, Mark N.; McClain, Kathleen M.; Jones, Michael E.; Adami, Hans-Olov; Agnoli, Claudia; Baglietto, Laura; Bernstein, Leslie; Bertrand, Kimberly A.; Blot, William J.; Boutron-Ruault, Marie-Christine; Butler, Lesley; Chen, Yu; Doody, Michele M.; Dossus, Laure; Eliassen, A. Heather; Giles, Graham G.; Gram, Inger T.; Hankinson, Susan E.; Hoffman-Bolton, Judy; Kaaks, Rudolf; Key, Timothy J.; Kirsh, Victoria A.; Kitahara, Cari M.; Koh, Woon-Puay; Larsson, Susanna C.; Lund, Eiliv; Ma, Huiyan; Merritt, Melissa A.; Milne, Roger L.; Navarro, Carmen; Overvad, Kim; Ozasa, Kotaro; Palmer, Julie R.; Peeters, Petra H.; Riboli, Elio; Rohan, Thomas E.; Sadakane, Atsuko; Sund, Malin; Tamimi, Rulla M.; Trichopoulou, Antonia; Vatten, Lars; Visvanathan, Kala; Weiderpass, Elisabete; Willett, Walter C.; Wolk, Alicja; Zeleniuch-Jacquotte, Anne; Zheng, Wei; Sandler, Dale P.; Swerdlow, Anthony J.

2017-01-01

Breast cancer is a leading cancer diagnosis among premenopausal women around the world. Unlike rates in postmenopausal women, incidence rates of advanced breast cancer have increased in recent decades for premenopausal women. Progress in identifying contributors to breast cancer risk among premenopausal women has been constrained by the limited numbers of premenopausal breast cancer cases in individual studies and resulting low statistical power to subcategorize exposures or to study specific subtypes. The Premenopausal Breast Cancer Collaborative Group was established to facilitate cohort-based analyses of risk factors for premenopausal breast cancer by pooling individual-level data from studies participating in the United States National Cancer Institute Cohort Consortium. This paper describes the Group, including the rationale for its initial aims related to pregnancy, obesity, and physical activity. We also describe the 20 cohort studies with data submitted to the Group by June 2016. The infrastructure developed for this work can be leveraged to support additional investigations. PMID:28600297

Subclinical Hyperthyroidism-A Cohort Study

International Nuclear Information System (INIS)

Hashim, R.; Anwer, M. S.; Khan, F. A.; Ijaz, A.

2013-01-01

Objective: To compare the development of overt hyperthyroidism in a cohort of patients of subclinical hyperthyroidism (SCR) and in subjects with normal thyroid function tests. Study Design: A cohort study. Place and Duration of study: The study was conducted in the department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology, Rawalpindi from Sept 2006 to Sept 2007. Patients and Methods: Fifty patients of SCR and almost equal number of age and sex-matched subjects with normal Thyroid function test (TFT) were included in the study as controls. Subclinical hyperthyroid patients and controls were followed for a period of one year on a six monthly basis. The patients were examined for signs and symptoms of hyperthyroidism and serum TSH, total T3 and free T4 were estimated. The clinical history, physical examination and TFT results were recorded. Five ml of blood was collected for serum thyroid profile in plain tube. Hormonal analysis(TSH, T4 and T3) was done for the patients and the controls enrolled in the study. The TFTs was analyzed using Chemiluminescence Immunoassay technique on Immulite 2000 an automated, random access, immunoassay analyzer. Results: Six (12%) out of 50 cases of the SCR patients and 2 (4%) out of 50 controls developed overt hyperthyroidism. SCR had no significant risk for conversion to overt hyperthyroidism as compared to healthy controls in this study. In addition to initial levels of serum TSH were one of important predictor for conversion of SCR to overt hyperthyroidism. Conclusion: Patients with SCR have no significant risk but showed an increase in frequency of conversion to overt hyperthyroidism (12% in this study) as compared to controls. (author)

Polymorphisms in the xenobiotic transporter Multidrug Resistance 1 (MDR1) and interaction with meat intake in relation to risk of colorectal cancer in a Danish prospective case-cohort study

DEFF Research Database (Denmark)

Andersen, Vibeke; Østergaard, Mette; Christensen, Jane

2009-01-01

(rs5275) polymorphisms in the 3'-untranslated region. The polymorphisms were assessed together with lifestyle factors in a nested case-cohort study of 359 cases and a random cohort sample of 765 participants from the Danish prospective Diet, Cancer and Health study. Results Carriers of the variant......Background The xenobiotic transporters, Multidrug Resistance 1 (MDR1/ABCB1) and Breast Cancer Resistance Protein (BCRP/ABCG2) may restrict intestinal absorption of various carcinogens, including heterocyclic amines (HCA) and polycyclic aromatic hydrocarbons (PAH). Cyclooxygenase-2 (COX-2) derived...... prostaglandins promote gastrointestinal carcinogenesis, affecting angiogenesis, apoptosis, and invasiveness. The aim of this study was to investigate if polymorphisms in these genes were associated with risk of colorectal cancer (CRC), and to investigate possible interactions with lifestyle factors...

Risk of Parkinson's disease following zolpidem use: a retrospective, population-based cohort study.

Science.gov (United States)

Huang, Hui-Chun; Tsai, Chon-Haw; Muo, Chih-Hsin; Lin, Kang-Hsu; Lu, Ming-Kuei; Sung, Fung-Chang; Kao, Chia-Hung

2015-01-01

To evaluate the influence of long-term zolpidem use on the incidence of developing Parkinson's disease. 2,961 subjects who used zolpidem for the first time longer than 3 months between 1998 and 2000 were identified in the National Health Insurance system of Taiwan. Subjects without a history of zolpidem use were randomly selected as a comparison cohort and frequency matched to zolpidem users based on age, sex, and index date. The diagnosis of Parkinson's disease was based on the criteria of the International Classification of Diseases, Ninth Revision, Clinical Modification. Its incidence until the end of 2009 was calculated and its hazard ratios (HRs) and 95% CIs were estimated using Cox proportional hazards regression models and Kaplan-Meier analysis. The overall incidence of Parkinson's disease was greater among zolpidem users than in the comparison cohort (HR = 1.88; 95% CI, 1.45-2.45). However, there was no difference in Parkinson's disease incidence between these 2 cohorts after 5 years of observation. The risk of Parkinson's disease increased with increasing zolpidem dose, with an HR of 0.70 for low-dose users (zolpidem only (HR = 2.35; 95% CI, 1.66-3.33) compared to those using benzodiazepines only (HR = 1.31; 95% CI, 0.91-1.90). By stratified analysis, zolpidem use with concurrent depression (HR = 4.79) increased the risk of Parkinson's disease compared to that of zolpidem users without concurrent depression. Zolpidem use might unmask preclinical Parkinson's disease, especially in patients with depression. However, large population-based, unbiased, randomized trials are warranted to confirm this finding. © Copyright 2015 Physicians Postgraduate Press, Inc.

Incidence of sudden unexpected death in epilepsy in community-based cohort in China.

Science.gov (United States)

Ge, Yan; Ding, Ding; Zhang, Qing; Yang, Bin; Wang, Taiping; Li, Beixu; Wang, Jie; Luo, Jianfeng; Kwan, Patrick; Wang, Wenzhi; Hong, Zhen; Sander, Josemir W

2017-11-01

Sudden unexpected death in epilepsy (SUDEP) is associated with the high premature mortality observed among people with epilepsy. It is, however, considered a rare event in China, probably because of lack of awareness and limitation of studies in the country. We aimed to provide some initial estimation of the burden of SUDEP in China. We established a large Chinese community-based cohort of people with epilepsy between January 2010 and December 2011. For any participant who died during follow-up, detailed information on cause of death was obtained using a specifically designed Verbal Autopsy Questionnaire. All cases were reviewed by a multidisciplinary expert panel and reinvestigated if necessary. Sudden unexpected death in epilepsy incidence rates were estimated and case details provided. The cohort consisted of 1562 people and during a median 5years follow-up, 72 deaths were reported. The all-causes death incidence was 11.23 (95% CI 8.86-14.07) per 1000 person-years. Fifteen died suddenly and unexpectedly in a reasonable state of health in the week preceding death. We recorded detailed information of these 15 deaths. Thirteen were considered to be probable SUDEP and two possible SUDEP. The incidence of probable SUDEP was 2.03 (95% CI 1.13-3.38) per 1000 person-years, and the incidence of all suspected (probable and possible) SUDEP was 2.34 (95% CI 1.36-3.77) per 1000 person-years. The incidence of SUDEP was relatively high among Chinese people with epilepsy when compared with that in previous community-based studies from high-income countries. The burden of SUDEP in China requires further assessments. Copyright © 2017 Elsevier Inc. All rights reserved.

Periodontal Disease and Incident Lung Cancer Risk: A Meta-Analysis of Cohort Studies.

Science.gov (United States)

Zeng, Xian-Tao; Xia, Ling-Yun; Zhang, Yong-Gang; Li, Sheng; Leng, Wei-Dong; Kwong, Joey S W

2016-10-01

Periodontal disease is linked to a number of systemic diseases such as cardiovascular diseases and diabetes mellitus. Recent evidence has suggested periodontal disease might be associated with lung cancer. However, their precise relationship is yet to be explored. Hence, this study aims to investigate the association of periodontal disease and risk of incident lung cancer using a meta-analytic approach. PubMed, Scopus, and ScienceDirect were searched up to June 10, 2015. Cohort and nested case-control studies investigating risk of lung cancer in patients with periodontal disease were included. Hazard ratios (HRs) were calculated, as were their 95% confidence intervals (CIs) using a fixed-effect inverse-variance model. Statistical heterogeneity was explored using the Q test as well as the I(2) statistic. Publication bias was assessed by visual inspection of funnel plots symmetry and Egger's test. Five cohort studies were included, involving 321,420 participants in this meta-analysis. Summary estimates based on adjusted data showed that periodontal disease was associated with a significant risk of lung cancer (HR = 1.24, 95% CI = 1.13 to 1.36; I(2) = 30%). No publication bias was detected. Subgroup analysis indicated that the association of periodontal disease and lung cancer remained significant in the female population. Evidence from cohort studies suggests that patients with periodontal disease are at increased risk of developing lung cancer.

Risk of intracerebral hemorrhage associated with phenprocoumon exposure: a nested case-control study in a large population-based German database.

Science.gov (United States)

Behr, Sigrid; Andersohn, Frank; Garbe, Edeltraut

2010-07-01

Intracerebral hemorrhage (ICH) is the most serious complication of oral anticoagulation. This study investigated the risk of ICH for phenprocoumon which is the most widely used oral anticoagulant in Germany. We conducted a nested case-control study in a cohort of 13.4 million insurants of 4 German statutory health insurances (SHIs) who were continuously enrolled for 6 months prior to cohort entry. Cases were patients hospitalized for ICH. Ten controls were matched to each case by SHI, birth year, and sex using incidence density sampling. Rate ratios (RR) of ICH for current phenprocoumon use as compared to non-use were estimated from odds ratios calculated by conditional logistic regression analyses considering multiple risk factors. Analysis of the full cohort revealed a strong increase in incidence of ICH with increasing age. In the nested case-control study including 8138 cases of ICH and 81,373 matched controls, we observed an increased risk of ICH for current phenprocoumon exposure that varied with age. The phenprocoumon-associated risk of ICH was lower in older age groups with RRs from 4.20 (95% confidence interval (CI) 2.44-7.21) for phenprocoumon users less than 55 years of age to 2.43 (95%CI, 1.81-3.27) for those older than 85 years. Our study confirmed known risk factors of ICH. Phenprocoumon exposure was associated with an increased risk of ICH. The interaction of risk for phenprocoumon with age was unexpected and needs further study. (c) 2010 John Wiley & Sons, Ltd.

An ADAM33 polymorphism associates with progression of preschool wheeze into childhood asthma: a prospective case-control study with replication in a birth cohort study.

Science.gov (United States)

Klaassen, Ester M M; Penders, John; Jöbsis, Quirijn; van de Kant, Kim D G; Thijs, Carel; Mommers, Monique; van Schayck, Constant P; van Eys, Guillaume; Koppelman, Gerard H; Dompeling, Edward

2015-01-01

The influence of asthma candidate genes on the development from wheeze to asthma in young children still needs to be defined. To link genetic variants in asthma candidate genes to progression of wheeze to persistent wheeze into childhood asthma. In a prospective study, children with recurrent wheeze from the ADEM (Asthma DEtection and Monitoring) study were followed until the age of six. At that age a classification (transient wheeze or asthma) was based on symptoms, lung function and medication use. In 198 children the relationship between this classification and 30 polymorphisms in 16 asthma candidate genes was assessed by logistic regression. In case of an association based on a pchildhood asthma. When replicated in the KOALA study, ADAM33 rs528557 showed a negative association of the CG/GG-genotype with progression of recurrent wheeze into childhood asthma (0.50 (0.26-0.97) p = 0.04) and no association with preschool wheeze. Polymorphisms in ADAM33, ORMDL3/GSDMB and IL4 were associated with childhood asthma in a group of children with recurrent wheeze. The replication of the negative association of the CG/GG-genotype of rs528557 ADAM33 with childhood asthma in an independent birth cohort study confirms that a compromised ADAM33 gene may be implicated in the progression of wheeze into childhood asthma.

[Application of nested case-control study on safe evaluation of post-marketing traditional Chinese medicine injection].

Science.gov (United States)

Xiao, Ying; Zhao, Yubin; Xie, Yanming

2011-10-01

The nested case-control study design (or the case-control in a cohort study) is described here as a new study design used in safe evaluation of post-marketing traditional Chinese medicine injection. In the nested case-control study, cases of a disease that occur in a defined cohort are identified and, for each, a specified number of matched controls is selected from among those in the cohort who have not developed the disease by the time of disease occurrence in the case. For many research questions, the nested case-control design potentially offers impressive reductions in costs and efforts of data collection and analysis compared with the full cohort approach, with relatively minor loss in statistical efficiency. The nested case-control design is particularly advantageous for studies in safe evaluation of post-marketing traditional Chinese medicine injection. Some examples of the application of nested case-control study were given.

Malignant transformation of Taiwanese patients with oral leukoplakia: A nationwide population-based retrospective cohort study

Directory of Open Access Journals (Sweden)

Tung-Yuan Wang

2018-05-01

Full Text Available Background/Purpose: Oral leukoplakia (OL is one of the clinically diagnosed oral potentially malignant disorders (OPMDs with an increased risk of oral cancer development. In this study, we investigated the malignant transformation of OL in Taiwanese population. Methods: A retrospective cohort study was analyzed from Taiwan's National Health Insurance Research Database. A comparison cohort was randomly frequency-matched with the OL cohort according to age, sex, and index year. Oral submucous fibrosis (OSF and oral lichen planus (OLP were further stratified to evaluate the possible synergistic effects for OL-associated malignant transformation. Results: In this cohort, 102 (5.374% of 1898 OL patients were observed to transform into oral cancer. The malignant transformation rate was 26.40-fold in the OL cohort than in the comparison cohort after adjustment (95% confidence intervals 18.46–37.77. To further stratify with OSF and OLP, OL with OSF (58.38; 95% confidence intervals 34.61–98.50 and OL with OLP (36.88; 95% confidence intervals 8.90–152.78 had higher risk of malignant transformation rate than OL alone (27.01; 95% confidence intervals 18.91–38.59. The Kaplan–Meier plot revealed the free of malignant transformation rate was significant over the 13 years follow-up period (log-rank test, p < 0.001. Conclusion: OL patients exhibited a significantly higher risk of malignant transformation than those without OL. In addition, both OSF and OLP could enhance malignant transformation in patients with OL. However, further studies are required to identify the histopathological and clinical parameters in the pathogenesis of malignant transformation among OPMDs. Keywords: Oral leukoplakia, Oral submucous fibrosis, Oral lichen planus, Malignant transformation, Nationwide population, Cohort study, Taiwan

Comparison of the effectiveness of two mumps vaccines during an outbreak in Switzerland in 1999 and 2000: A case-cohort study

International Nuclear Information System (INIS)

Richard, Jean-Luc; Zwahlen, Marcel; Feuz, Mirjam; Matter, Hans C.

2003-01-01

In two recent nation-wide outbreaks of mumps in Switzerland two-thirds of young children with clinical mumps had a history of primary vaccination. On average, measles-mumps-rubella (MMR) vaccination coverage is 80%. Two types of vaccine are commonly used: Jeryl-Lynn and Rubini. The effectiveness of the latter has been questioned in several publications. The authors therefore compared Rubini to Jeryl-Lynn in a case-cohort study. The study included 111 young children with clinical mumps who had been reported to the Swiss Federal Office of Public Health (SFOPH) by primary care physicians of the Swiss Sentinel Surveillance Network (SSSN) between January 1999 and May 2000. Sentinel physicians also sampled 661 children from the same birth cohort as the cases. While we found no evidence for the effectiveness of the Rubini strain, vaccination with the Jeryl-Lynn strain was 70% effective against clinical mumps. Furthermore, children vaccinated with the Rubini strain attended primary health care more frequently with clinical mumps than those who had received Jeryl-Lynn (odds ratio: 2.4; 95% confidence interval (CI): 1.3, 4.7). Restricting the analysis to laboratory confirmed cases increased the odds ratio to 18.4 (95% CI: 2.5, 811.2). Our study confirms the low effectiveness of the Rubini strain vaccine in the field. This vaccine should therefore be considered inappropriate for the control and elimination of mumps and its use should be discontinued. As other vaccines with comparable quality and safety standards and a substantially higher effectiveness are available the MMR vaccination program in Switzerland will not be compromised if the use of Rubini is no longer recommended

A case-control study of non-AIDS-defining cancers in a prospective cohort of HIV-infected patients.

Science.gov (United States)

Rodríguez Arrondo, Francisco; von Wichmann, Miguel Ángel; Camino, Xabier; Goenaga, Miguel Ángel; Ibarguren, Maialen; Azcune, Harkaitz; Bustinduy, María Jesús; Ferrero, Oscar; Muñoz, Josefa; Ibarra, Sofía; Aguirrebengoa, Koldo; Goicoetxea, Josune; Bereciartua, Elena; Montejo, Miguel; García, M Asunción; Martínez, Eduardo; Portu, Joseba; Metola, Luis; Silvariño, Rafael; Sarasqueta, Cristina; Arrizabalaga, Julio; Iribarren, Jose Antonio

2018-04-23

We present a case-control study of non-AIDS-defining cancers (NADCs) in a cohort of HIV-infected patients where we value the incidence, survival and prognostic factors of mortality. All NADCs diagnosis conducted from 2007 to 2011 in 7 hospitals were collected prospectively, with a subsequent follow up until December 2013. A control group of 221 HIV patients without a diagnosis of cancer was randomly selected. Two hundred and twenty-one NADCs were diagnosed in an initial cohort of 7,067 HIV-infected patients. The most common were: hepatocellular carcinoma 20.5%, lung 18.7%, head and neck 11.9% and anal 10.5%. The incidence rate of NADCs development was 7.84/1,000 people-year. In addition to aging and smoking, time on ART (OR 1.11; 95% CI 1.05-1.17) and PI use (OR 1.72; 95% CI 1.0-2.96) increased the risk of developing a NADC. During follow-up 53.42% died, with a median survival time of 199.5 days. In the analysis of the prognostic factors of mortality the low values of CD4 at tumour diagnosis (OR 0.99; 95% CI 0.99-1.0; P=.033), and the previous diagnosis of AIDS (OR 2.06; 95% CI 1.08-3.92) were associated with higher mortality. Predictors of NADCs in our cohort were age, smoking, CD4 lymphocytes and time on ART. Mortality is high, with NADC risk factors being low CD4 count and previous diagnosis of AIDS. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

A Cohort Study on Meniscal Lesions among Airport Baggage Handlers

DEFF Research Database (Denmark)

Mikkelsen, Sigurd; Brauer, Charlotte; Pedersen, Ellen Bøtker

2016-01-01

socioeconomic background and less knee-straining work. Baggage handlers lifted suitcases with an average weight of approximately 15 kg, in total approximately five tonnes during a 9-hour workday. The cohort was followed in the National Patient Register and Civil Registration System. The outcome was a first time......Meniscal lesions are common and may contribute to the development of knee arthrosis. A few case-control and cross-sectional studies have identified knee-straining work as risk factors for meniscal lesions, but exposure-response relations and the role of specific exposures are uncertain...... of unskilled men employed at Copenhagen Airport or in other companies in the metropolitan Copenhagen area from 1990 to 2012 (the Copenhagen Airport Cohort). The cohort at risk included 3,307 airport baggage handlers with heavy lifting and kneeling or squatting work tasks and 63,934 referents with a similar...

Cohort profile: the lidA Cohort Study-a German Cohort Study on Work, Age, Health and Work Participation.

Science.gov (United States)

Hasselhorn, Hans Martin; Peter, Richard; Rauch, Angela; Schröder, Helmut; Swart, Enno; Bender, Stefan; du Prel, Jean-Baptist; Ebener, Melanie; March, Stefanie; Trappmann, Mark; Steinwede, Jacob; Müller, Bernd Hans

2014-12-01

The lidA Cohort Study (German Cohort Study on Work, Age, Health and Work Participation) was set up to investigate and follow the effects of work and work context on the physical and psychological health of the ageing workforce in Germany and subsequently on work participation. Cohort participants are initially employed people subject to social security contributions and born in either 1959 (n = 2909) or 1965 (n = 3676). They were personally interviewed in their homes in 2011 and will be visited every 3 years. Data collection comprises socio-demographic data, work and private exposures, work ability, work and work participation attitudes, health, health-related behaviour, personality and attitudinal indicators. Employment biographies are assessed using register data. Subjective health reports and physical strength measures are complemented by health insurance claims data, where permission was given. A conceptual framework has been developed for the lidA Cohort Study within which three confirmatory sub-models assess the interdependencies of work and health considering age, gender and socioeconomic status. The first set of the data will be available to the scientific community by 2015. Access will be given by the Research Data Centre of the German Federal Employment Agency at the Institute for Employment Research (http://fdz.iab.de/en.aspx). © The Author 2014. Published by Oxford University Press on behalf of the International Epidemiological Association.

Outcomes of Acellular Dermal Matrix for Immediate Tissue Expander Reconstruction with Radiotherapy: A Retrospective Cohort Study.

Science.gov (United States)

Craig, Elizabeth S; Clemens, Mark W; Koshy, John C; Wren, James; Hong, Zhang; Butler, Charles; Garvey, Patrick; Selber, Jesse; Kronowitz, Steven

2018-05-24

Despite increasing literature support for the use of acellular dermal matrix (ADM) in expander-based breast reconstruction, the effect of ADM on clinical outcomes in the presence of post-mastectomy radiation therapy (PMRT) has not been well described. To analyze the impact ADM plays on clinical outcomes on immediate tissue expander (ITE) reconstruction undergoing PMRT. We retrospectively reviewed patients who underwent ITE breast reconstruction from 2004 to 2014 at MD Anderson Cancer Center. Patients were categorized into four cohorts: ADM, ADM with PMRT, non-ADM, and non-ADM with PMRT. Outcomes and complications were compared between cohorts. Over ten years, 957 patients underwent ITE reconstruction (683 non-ADM, 113 non-ADM with PMRT, 486 ADM, and 88 ADM with PMRT) with 1,370 reconstructions. Overall complication rates for the ADM and non-ADM cohorts were 39.0 and 16.7%, respectively (p <0.001). Within both cohorts, mastectomy skin flap necrosis (MSFN) was the most common complication, followed by infection. ADM use was associated with a significantly higher rate of infections and seromas in both radiated and non-radiated groups; however, when comparing radiated cohorts, the incidence of explantation was significantly lower with the use of ADM. The decision to use ADM for expander-based breast reconstruction should be performed with caution, given higher overall rates of complications, including infections and seromas. There may, however, be a role for ADM in cases requiring PMRT, as the overall incidence of implant failure is lower than non-ADM cases.

Incidence of non-lung solid cancers in Czech uranium miners: A case-cohort study

International Nuclear Information System (INIS)

Kulich, M.; Rericha, V.; Rericha, R.; Shore, D.L.; Sandler, D.P.

2011-01-01

Objectives: Uranium miners are chronically exposed to radon and its progeny, which are known to cause lung cancer and may be associated with leukemia. This study was undertaken to evaluate risk of non-lung solid cancers among uranium miners in Pribram region, Czech Republic. Methods: A retrospective stratified case-cohort study in a cohort of 22,816 underground miners who were employed between 1949 and 1975. All incident non-lung solid cancers were ascertained among miners who worked underground for at least 12 months (n=1020). A subcohort of 1707 subjects was randomly drawn from the same population by random sampling stratified on age. The follow-up period lasted from 1977 to 1996. Results: Relative risks comparing 180 WLM (90th percentile) of cumulative lifetime radon exposure to 3 WLM (10th percentile) were 0.88 for all non-lung solid cancers combined (95% CI 0.73-1.04, n=1020), 0.87 for all digestive cancers (95% CI 0.69-1.09, n=561), 2.39 for gallbladder cancer (95% CI 0.52-10.98, n=13), 0.79 for larynx cancer (95% CI 0.38-1.64, n=62), 2.92 for malignant melanoma (95% CI 0.91-9.42, n=23), 0.84 for bladder cancer (95% CI 0.43-1.65, n=73), and 1.13 for kidney cancer (95% CI 0.62-2.04, n=66). No cancer type was significantly associated with radon exposure; only malignant melanoma and gallbladder cancer showed elevated but non-significant association with radon. Conclusions: Radon was not significantly associated with incidence of any cancer of interest, although a positive association of radon with malignant melanoma and gallbladder cancer cannot be entirely ruled out. - Research highlights: → Uranium miners are chronically exposed to radon. → We evaluate risk of non-lung solid cancers among uranium miners. → No cancer type was significantly associated with radon exposure. → Malignant melanoma and gallbladder cancer showed non-significant elevated risk.

An Agent-Based Modeling Template for a Cohort of Veterans with Diabetic Retinopathy.

Directory of Open Access Journals (Sweden)

Theodore Eugene Day

Full Text Available Agent-based models are valuable for examining systems where large numbers of discrete individuals interact with each other, or with some environment. Diabetic Veterans seeking eye care at a Veterans Administration hospital represent one such cohort.The objective of this study was to develop an agent-based template to be used as a model for a patient with diabetic retinopathy (DR. This template may be replicated arbitrarily many times in order to generate a large cohort which is representative of a real-world population, upon which in-silico experimentation may be conducted.Agent-based template development was performed in java-based computer simulation suite AnyLogic Professional 6.6. The model was informed by medical data abstracted from 535 patient records representing a retrospective cohort of current patients of the VA St. Louis Healthcare System Eye clinic. Logistic regression was performed to determine the predictors associated with advancing stages of DR. Predicted probabilities obtained from logistic regression were used to generate the stage of DR in the simulated cohort.The simulated cohort of DR patients exhibited no significant deviation from the test population of real-world patients in proportion of stage of DR, duration of diabetes mellitus (DM, or the other abstracted predictors. Simulated patients after 10 years were significantly more likely to exhibit proliferative DR (P<0.001.Agent-based modeling is an emerging platform, capable of simulating large cohorts of individuals based on manageable data abstraction efforts. The modeling method described may be useful in simulating many different conditions where course of disease is described in categorical stages.

Geography, population, demography, socioeconomic, anthropometry, and environmental status in the MAL-ED cohort and case-control study Sites in Fortaleza, Ceará, Brazil.

Science.gov (United States)

Lima, Aldo A M; Oriá, Reinaldo B; Soares, Alberto M; Filho, José Q; de Sousa, Francisco; Abreu, Cláudia B; Bindá, Alexandre; Lima, Ila; Quetz, Josiane; Moraes, Milena; Maciel, Bruna; Costa, Hilda; Leite, Alvaro M; Lima, Noélia L; Mota, Francisco S; Di Moura, Alessandra; Scharf, Rebecca; Barrett, Leah; Guerrant, Richard L

2014-11-01

The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort in the study's Fortaleza, Brazil, catchment area has a population of approximately 82 300 inhabitants. Most of the households (87%) have access to clean water, 98% have electricity, and 69% have access to improved toilet/sanitation. Most childbirths occur at the hospital, and the under-5 mortality rate is 20 per 1000 live births. The MAL-ED case-control study population, identified through the Institute for the Promotion of Nutrition and Human Development (IPREDE), serves 600 000 inhabitants from areas totaling about 42% of the city of Fortaleza. IPREDE receives referrals from throughout the state of Ceará for infant nutrition, and provides services including teaching activities and the training of graduate students and health professionals, while supporting research projects on child nutrition and health. In this article, we describe the geographic, demographic, socioeconomic, anthropometric, and environmental status of the MAL-ED cohort and case-control study populations in Fortaleza, Brazil. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Profiling Consumers Based on Their Beverage Consumption Patterns. A Cross-Cultural Study by Cohorts

NARCIS (Netherlands)

Johan van Berkel; Ana Pertejo; Martin de Boer; Alexandra Kenyon

2012-01-01

The purpose of the research we undertook for this Conference Paper was to investigate whether marketing campaigns for specific types of drinks could be directed towards age cohorts rather than towards intercultural differences between countries. We developed consumer profiles based on drinking

RANTES/CCL5 and risk for coronary events: Results from the MONICA/KORA Augsburg case-cohort, Athero-express and CARDIoGRAM studies

OpenAIRE

Kathiresan, Sekar; Reilly, Muredach; Samani, Nilesh; Schunkert, Heribert; Erdmann, Jeanette; Moll, Frans; Boerwinkle, Eric; Hall, Anne; Hengstenberg, Christian; König, Inke; Laaksonen, Reijo; McPherson, Ruth; Thompson, John; Thorsteinsdottir, Unnur; Ziegler, Andreas

2011-01-01

textabstractBackground: The chemokine RANTES (regulated on activation, normal T-cell expressed and secreted)/CCL5 is involved in the pathogenesis of cardiovascular disease in mice, whereas less is known in humans. We hypothesised that its relevance for atherosclerosis should be reflected by associations between CCL5 gene variants, RANTES serum concentrations and protein levels in atherosclerotic plaques and risk for coronary events. Methods and Findings: We conducted a case-cohort study withi...

Fatherhood status and risk of prostate cancer: nationwide, population-based case-control study.

Science.gov (United States)

Wirén, Sara M; Drevin, Linda I; Carlsson, Sigrid V; Akre, Olof; Holmberg, Erik C; Robinson, David E; Garmo, Hans G; Stattin, Pär E

2013-08-15

Previous studies have shown a decreased risk of prostate cancer for childless men; however, the cause of the association remains to be elucidated. The aim of our study was to assess the risk of prostate cancer by fatherhood status, also considering potential confounding factors. In a case-control study in Prostate Cancer data Base Sweden 2.0, a nationwide, population-based cohort, data on number of children, marital status, education, comorbidity and tumor characteristics obtained through nationwide healthcare registers and demographic databases for 117,328 prostate cancer cases and 562,644 controls, matched on birth year and county of residence, were analyzed. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for prostate cancer overall and by risk category, adjusting for marital status and education. Childless men had a decreased risk of prostate cancer compared to fathers, OR = 0.83 (95% CI = 0.82-0.84), and risk was lower for low-risk prostate cancer, OR = 0.74 (95% CI = 0.72-0.77), than for metastatic prostate cancer, OR = 0.93 (95% CI = 0.90-0.97). Adjustment for marital status and education attenuated the association in the low-risk category, adjusted OR = 0.87 (95% CI = 0.84-0.91), whereas OR for metastatic cancer remained virtually unchanged, adjusted OR = 0.92 (95% CI = 0.88-0.96). Our data indicate that the association between fatherhood status and prostate cancer to a large part is due to socioeconomic factors influencing healthcare-seeking behavior including testing of prostate-specific antigen levels. Copyright © 2013 UICC.

Is schizophrenia associated with an increased risk of chronic kidney disease? A nationwide matched-cohort study.

Science.gov (United States)

Tzeng, Nian-Sheng; Hsu, Yung-Ho; Ho, Shinn-Ying; Kuo, Yu-Ching; Lee, Hua-Chin; Yin, Yun-Ju; Chen, Hong-An; Chen, Wen-Liang; Chu, William Cheng-Chung; Huang, Hui-Ling

2015-01-27

The impact of schizophrenia on vital diseases, such as chronic kidney disease (CKD), has not as yet been verified. This study aims to establish whether there is an association between schizophrenia and CKD. A nationwide matched cohort study. Taiwan's National Health Insurance Research Database. A total of 2338 patients with schizophrenia, and 7014 controls without schizophrenia (1:3), matched cohort for sex, age group, geography, urbanisation and monthly income, between 1 January 2003 and 31 December 2007, based on the International Classifications of Disease Ninth Edition (ICD-9), Clinical Modification codes. After making adjustments for confounding risk factors, a Cox proportional hazards model was used to compare the risk of developing CKD during a 3-year follow-up period from the index date. Of the 2338-subject case cohort, 163 (6.97%) developed a CKD, as did 365 (5.20%) of the 7014 control participants. Cox proportional hazards regression analysis revealed that patients with schizophrenia were more likely to develop CKD (HR=1.36, 95% CI 1.13 to 1.63; pschizophrenia was 1.25 (95% CI 1.04 to 1.50; prisk of CKD in patients with schizophrenia. The findings from this population-based retrospective cohort study suggest that schizophrenia is associated with a 25% increase in the risk of developing CKD within only a 3-year follow-up period. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Gonorrhoea and Syphilis Epidemiology in Flemish General Practice 2009–2013: Results from a Registry-based Retrospective Cohort Study Compared with Mandatory Notification

Directory of Open Access Journals (Sweden)

Christoph Schweikardt

2016-09-01

Full Text Available Background: The number of newly diagnosed gonorrhoea and syphilis cases has increased in Flanders in recent years. Our aim was to investigate, to which extent these diagnoses were registered by general practitioners (GPs, and to examine opportunities and limits of the Intego database in this regard. Methods: Data from a retrospective cohort study based on the Flemish Intego general practice database was analyzed for the years 2009–2013. Case definitions were applied. Due to small case numbers obtained, cases were pooled and averaged over the observation period. Frequencies were compared with those calculated from figures of mandatory notification. Results: A total of 91 gonorrhoea and 23 syphilis cases were registered. The average Intego annual frequency of gonorrhoea cases obtained was 11.9 (95% Poisson confidence interval (CI 9.6; 14.7 per 100,000 population, and for syphilis 3.0 (CI 1.9; 4.5, respectively, while mandatory notification was calculated at 14.0 (CI: 13.6, 14.4 and 7.0 (CI: 6.7, 7.3, respectively. Conclusion: In spite of limitations such as small numbers and different case definitions, comparison with mandatory notification suggests that the GP was involved in the large majority of gonorrhoea cases, while the majority of new syphilis cases did not come to the knowledge of the GP.

Acromegaly incidence, prevalence, complications and long-term prognosis: a nationwide cohort study.

Science.gov (United States)

Dal, Jakob; Feldt-Rasmussen, Ulla; Andersen, Marianne; Kristensen, Lars Ø; Laurberg, Peter; Pedersen, Lars; Dekkers, Olaf M; Sørensen, Henrik Toft; Jørgensen, Jens Otto L

2016-09-01

Valid data on acromegaly incidence, complications and mortality are scarce. The Danish Health Care System enables nationwide studies with complete follow-up and linkage among health-related databases to assess acromegaly incidence, prevalence, complications and mortality in a population-based cohort study. All incident cases of acromegaly in Denmark (1991-2010) were identified from health registries and validated by chart review. We estimated the annual incidence rate of acromegaly per 10(6) person-years (py) with 95% confidence intervals (95% CIs). For every patient, 10 persons were sampled from the general population as a comparison cohort. Cox regression and hazard ratios (HRs) with 95% confidence intervals (95% CIs) were used. Mean age at diagnosis (48.7 years (CI: 95%: 47.2-50.1)) and annual incidence rate (3.8 cases/10(6) persons (95% CI: 3.6-4.1)) among the 405 cases remained stable. The prevalence in 2010 was 85 cases/10(6) persons. The patients were at increased risk of diabetes mellitus (HR: 4.0 (95% CI: 2.7-5.8)), heart failure (HR: 2.5 (95% CI: 1.4-4.5)), venous thromboembolism (HR: 2.3 (95% CI: 1.1-5.0)), sleep apnoea (HR: 11.7 (95% CI: 7.0-19.4)) and arthropathy (HR: 2.1 (95% CI: 1.6-2.6)). The complication risk was also increased before the diagnosis of acromegaly. Overall mortality risk was elevated (HR: 1.3 (95% CI: 1.0-1.7)) but uninfluenced by treatment modality. (i) The incidence rate and age at diagnosis of acromegaly have been stable over decades, and the prevalence is higher than previously reported. (ii) The risk of complications is very high even before the diagnosis. (iii) Mortality risk remains elevated but uninfluenced by mode of treatment. © 2016 European Society of Endocrinology.

Increased risk of organic erectile dysfunction in patients with chronic fatigue syndrome: a nationwide population-based cohort study.

Science.gov (United States)

Chao, C-H; Chen, H-J; Wang, H-Y; Li, T-C; Kao, C-H

2015-07-01

Chronic fatigue syndrome (CFS) is a complex disorder characterized by profound and persistent fatigue and several comorbidities. CFS was previously reported to be associated with female sexual dysfunction. We propose that CFS might also be associated with organic erectile dysfunction (organic ED). We conducted a retrospective cohort study by using data from the National Health Insurance (NHI) Research Database. We identified 2156 male patients who were newly diagnosed with CFS between January 1, 2003 and December 31, 2006. After excluding those younger than 20 years and prevalent cases, 1976 patients were subjected to analysis, and 7904 people served as healthy controls. All study subjects were followed up from the index date to the date of organic ED diagnosis, withdrawal from the NHI program, or the end of 2011. Compared with the non-CFS cohort, the incidence density rate of organic ED was 1.88-fold higher than that in the CFS cohort (3.23 vs. 1.73 per 1000 person-years) with an adjusted hazard ratio (HR) of 1.88 (95% CI = 1.26-2.81) when adjusting for sex and comorbidities. The combined impacts of patients with CFS and cardiovascular disease (CVD), diabetes mellitus (DM), chronic kidney disease (CKD), depression, and anxiety showed a significant by joint association with organic ED risk compared with patients with no CFS and no counterpart comorbidity. The greatest magnitude of adjusted HR of ED for CFS was observed in individuals without any comorbidity (3.87, 1.95-7.66). The incidence of organic ED is higher among males aged 40 years and over for both CFS and non-CFS cohorts. As the number of comorbidity increases, the incidence of organic ED increases in males without CFS. Higher incidence of organic ED was observed in males with CVD, DM, CKD, depression, or anxiety for both CFS and non-CFS cohorts. © 2015 American Society of Andrology and European Academy of Andrology.

Risk of sexual transmitted infection following bipolar disorder: a nationwide population-based cohort study.

Science.gov (United States)

Lee, Shyh-Chyang; Hu, Chang-Kuo; Hung, Jeng-Hsiu; Yang, Albert C; Tsai, Shih-Jen; Huang, Min-Wei; Hu, Li-Yu; Shen, Cheng-Che

2018-04-03

Bipolar disorder is a severe mental disorder associated with functional and cognitive impairment. Numerous studies have investigated associations between sexually transmitted infections (STIs) and psychiatric illnesses. However, the results of these studies are controversial. We explored the association between bipolar disorder and the subsequent development of STIs, including human immunodeficiency virus infection; primary, secondary, and latent syphilis; genital warts; gonorrhea; chlamydial infection; and trichomoniasis. The bipolar cohort consisted of 1293 patients, and the comparison cohort consisted of 5172 matched control subjects without bipolar disorder. The incidence of subsequent STIs (hazard ratio (HR) = 2.23, 95% confidence interval (CI) 1.68-2.96) was higher among the patients with bipolar disorder than in the comparison cohort. Furthermore, female gender is a risk factor for acquisition of STIs (HR = 2.36, 95% CI 1.73-4.89) among patients with bipolar disorder. For individual STIs, the results indicated that the patients with bipolar disorder exhibited a markedly higher risk for subsequently contracting syphilis, genital warts, and trichomoniasis. Bipolar disorder might increase the risk of subsequent newly diagnosed STIs, including syphilis, genital warts, and trichomoniasis. Clinicians should pay particular attention to STIs in patients with bipolar disorder. Patients with bipolar disorder, especially those with a history of high-risk sexual behaviors, should be routinely screened for STIs. We identified patients who were diagnosed with bipolar disorder in the Taiwan National Health Insurance Research Database. A comparison cohort was constructed of patients without bipolar disorder who were matched with the bipolar cohort according to age and gender. The occurrence of subsequent new-onset STIs was evaluated in both cohorts.

Risk Factors for Loss to Follow-Up among People Who Inject Drugs in a Risk Reduction Program at Karachi, Pakistan. A Case-Cohort Study.

Directory of Open Access Journals (Sweden)

Rab Nawaz Samo

Full Text Available Retention of male people who inject drugs (PWIDs is a major challenge for harm reduction programs that include sterile needle/syringe exchange in resource-limited settings like Pakistan. We assessed the risk factors for loss to follow-up among male PWIDs enrolled in a risk reduction program in Karachi, Pakistan.We conducted a prospective cohort study among 636 HIV-uninfected male PWIDs enrolled during March-June 2009 in a harm reduction program for the estimation of incidence rate. At 24 months post-enrollment, clients who had dropped out of the program were defined as lost to follow-up and included as cases for case-cohort study.The median age of the participants was 29 years (interquartile range: 23-36. Active outreach accounted for 76% (483/636 of cohort recruits. Loss to follow-up at 24 months was 25.5% (162/636. In multivariable logistic regression, younger age (AOR: 0.97, 95% CI: 0.92-0.99, p = 0.028, clients from other provinces than Sindh (AOR: 1.49, 95% CI: 1.01-2.22, p = 0.046, having no formal education (AOR: 3.44, 95% CI: 2.35-4.90, p<0.001, a history of incarceration (AOR: 1.68, 95% CI: 1.14-2.46, p<0.008, and being homeless (AOR: 1.47, 95% CI: 1.00-2.19, p<0.049 were associated with loss to follow-up.Our cohort retained 74.5% of male PWIDs in Karachi for 24 months. Its loss to follow up rate suggested substantial ongoing programmatic challenges. Programmatic enhancements are needed for the highest risk male PWIDs, i.e., younger men, men not from Sindh Province, men who are poorly educated, formerly incarcerated, and/or homeless.

Migraine and risk of cardiovascular diseases: Danish population based matched cohort study.

Science.gov (United States)

Adelborg, Kasper; Szépligeti, Szimonetta Komjáthiné; Holland-Bill, Louise; Ehrenstein, Vera; Horváth-Puhó, Erzsébet; Henderson, Victor W; Sørensen, Henrik Toft

2018-01-31

To examine the risks of myocardial infarction, stroke (ischaemic and haemorrhagic), peripheral artery disease, venous thromboembolism, atrial fibrillation or atrial flutter, and heart failure in patients with migraine and in a general population comparison cohort. Nationwide, population based cohort study. All Danish hospitals and hospital outpatient clinics from 1995 to 2013. 51 032 patients with migraine and 510 320 people from the general population matched on age, sex, and calendar year. Comorbidity adjusted hazard ratios of cardiovascular outcomes based on Cox regression analysis. Higher absolute risks were observed among patients with incident migraine than in the general population across most outcomes and follow-up periods. After 19 years of follow-up, the cumulative incidences per 1000 people for the migraine cohort compared with the general population were 25 v 17 for myocardial infarction, 45 v 25 for ischaemic stroke, 11 v 6 for haemorrhagic stroke, 13 v 11 for peripheral artery disease, 27 v 18 for venous thromboembolism, 47 v 34 for atrial fibrillation or atrial flutter, and 19 v 18 for heart failure. Correspondingly, migraine was positively associated with myocardial infarction (adjusted hazard ratio 1.49, 95% confidence interval 1.36 to 1.64), ischaemic stroke (2.26, 2.11 to 2.41), and haemorrhagic stroke (1.94, 1.68 to 2.23), as well as venous thromboembolism (1.59, 1.45 to 1.74) and atrial fibrillation or atrial flutter (1.25, 1.16 to 1.36). No meaningful association was found with peripheral artery disease (adjusted hazard ratio 1.12, 0.96 to 1.30) or heart failure (1.04, 0.93 to 1.16). The associations, particularly for stroke outcomes, were stronger during the short term (0-1 years) after diagnosis than the long term (up to 19 years), in patients with aura than in those without aura, and in women than in men. In a subcohort of patients, the associations persisted after additional multivariable adjustment for body mass index and smoking

Associations Between Antiretroviral Treatment and Avascular Bone Necrosis: The Swiss HIV Cohort Study

Science.gov (United States)

Bayard, Cornelia; Ledergerber, Bruno; Flepp, Markus; Lecompte, Thanh; Moulin, Estelle; Hoffmann, Matthias; Weber, Rainer; Staehelin, Cornelia; Di Benedetto, Caroline; Fux, Christoph A; Tarr, Philip E; Aubert, V; Battegay, M; Bernasconi, E; Böni, J; Braun, DL; Bucher, HC; Calmy, A; Cavassini, M; Ciuffi, A; Dollenmaier, G; Egger, M; Elzi, L; Fehr, J; Fellay, J; Furrer, H; Fux, CA; Günthard, HF; Haerry, D; Hasse, B; Hirsch, HH; Hoffmann, M; Hösli, I; Kahlert, C; Kaiser, L; Keiser, O; Klimkait, T; Kouyos, RD; Kovari, H; Ledergerber, B; Martinetti, G; Martinez de Tejada, B; Marzolini, C; Metzner, KJ; Müller, N; Nicca, D; Pantaleo, G; Paioni, P; Rauch, A; Rudin, C; Scherrer, AU; Schmid, P; Speck, R; Stöckle, M; Tarr, P; Trkola, A; Vernazza, P; Wandeler, G; Weber, R; Yerly, S

2017-01-01

Abstract Background HIV-infected individuals have an increased risk of avascular bone necrosis (AVN). Antiretroviral therapy (ART) and particularly protease inhibitors (PI) have been implicated as a risk factor. We aimed to study the associations of ART with the occurrence of AVN among Swiss HIV Cohort Study participants (SHCS). Methods We used incidence density sampling to perform a case control study within the Swiss HIV Cohort Study (SHCS) comparing prospectively collected AVN cases and controls by conditional logistic regression analysis. To evaluate the effect of ART, multivariable models were adjusted for HIV transmission risk group, age, alcohol consumption, use of corticosteroids, CD4 nadir, maximum viral load, and pancreatitis. Results We compared 74 AVN cases and 145 controls. Associations with AVN were shown for heterosexual HIV acquisition (odds ratio [OR], 3.4; 95% confidence interval [CI], 1.1–10), alcohol consumption (OR, 2.7; 95% CI, 1.3–5.7), and hyperlipidemia (OR, 3.6; 95% CI, 1.4–9.6). After adding ART substances to the multivariable base model, there was evidence of an association for treatment with tenofovir (TDF) >1 year (OR, 4.4; 95% CI, 1.4–14) with AVN. Neither exposure to specific frequently prescribed ART combinations or ART drug classes nor cumulative ART exposure showed any associations with AVN. Conclusions In the HIV-infected population, a combination of risk factors such as heterosexual HIV acquisition, moderate to severe alcohol intake, and hyperlipidemia seem to contribute to AVN. ART does not seem to be a relevant risk factor for AVN. The association of prolonged TDF exposure with AVN needs to be confirmed. PMID:29026869

Is outdoor work associated with elevated rates of cerebrovascular disease mortality? A cohort study based on iron-ore mining.

Science.gov (United States)

Björ, Ove; Jonsson, Håkan; Damber, Lena; Burström, Lage; Nilsson, Tohr

2016-01-01

A cohort study that examined iron ore mining found negative associations between cumulative working time employed underground and several outcomes, including mortality of cerebrovascular diseases. In this cohort study, and using the same group of miners, we examined whether work in an outdoor environment could explain elevated cerebrovascular disease rates. This study was based on a Swedish iron ore mining cohort consisting of 13,000 workers. Poisson regression models were used to generate smoothed estimates of standardized mortality ratios and adjusted rate ratios, both models by cumulative exposure time in outdoor work. The adjusted rate ratio between employment classified as outdoor work ≥25 years and outdoor work 0-4 years was 1.62 (95 % CI 1.07-2.42). The subgroup underground work ≥15 years deviated most in occurrence of cerebrovascular disease mortality compared with the external reference population: SMR (0.70 (95 % CI 0.56-0.85)). Employment in outdoor environments was associated with elevated rates of cerebrovascular disease mortality. In contrast, work in tempered underground employment was associated with a protecting effect.

Feasibility and quality of cardiovascular disease prevention within a community-based health insurance program in rural Nigeria: an operational cohort study

NARCIS (Netherlands)

Hendriks, Marleen E.; Bolarinwa, Oladimeji A.; Wit, Ferdinand W. N. W.; Brewster, Lizzy M.; Odusola, Aina O.; Rosendaal, Nicole T. A.; Bindraban, Navin R.; Adenusi, Peju; Agbede, Kayode; Lange, Joep M. A.; Akande, Tanimola M.; Schultsz, Constance

2015-01-01

To assess the feasibility of providing guideline-based cardiovascular disease (CVD) prevention care within the context of a community-based health insurance program (CBHI) in rural Nigeria. A prospective operational cohort study was conducted in a primary healthcare clinic in rural Nigeria,

Maternal use of fertility drugs and risk of cancer in children--a nationwide population-based cohort study in Denmark.

Science.gov (United States)

Hargreave, Marie; Jensen, Allan; Nielsen, Thor Schütt Svane; Colov, Emilie Palmgren; Andersen, Klaus Kaae; Pinborg, Anja; Kjaer, Susanne Krüger

2015-04-15

Large population-based studies are needed to examine the effect of maternal use of fertility drugs on the risk of cancer in children, while taking into account the effect of the underlying infertility. A cohort of 123,322 children born in Denmark between 1964 and 2006 to 68,255 women who had been evaluated for infertility was established. We used a case-cohort design and calculated hazard ratios (HRs) for cancer in childhood (0-19 years) and in young adulthood (20-29 years) associated with maternal use of six groups of fertility drugs (clomiphene, gonadotropins [i.e., human menopausal gonadotropins and follicle-stimulating hormone], gonadotropin-releasing hormone analogs, human chorionic gonadotropins, progesterone and other fertility drugs). We found no statistically significant association between maternal use of fertility drugs and risk for overall cancer in childhood or young adulthood. However, with regard to specific cancers in childhood, our results showed that maternal use of progesterone before childbirth markedly increased the risks of their offspring for acute lymphocytic leukemia (any use: HR, 4.95; 95% CI, 1.69-14.54; ≥ three cycles of use: HR, 9.96; 95% CI, 2.63-37.77) and for sympathetic nervous system tumors (any use: HR, 5.79; 95% CI, 1.23-27.24; ≥ three cycles of use: HR, 8.51; 95% CI, 1.72-42.19). These findings show that maternal use of progesterone may increase the risk for specific cancers in the offspring. Additional large epidemiological studies are urgently needed to confirm our finding. © 2014 UICC.

Physical activity and risk of Amyotrophic Lateral Sclerosis in a prospective cohort study

NARCIS (Netherlands)

Gallo, Valentina; Vanacore, Nicola; Bueno-de-Mesquita, H Bas; Vermeulen, Roel; Brayne, Carol; Pearce, Neil; Wark, Petra A; Ward, Heather A; Ferrari, Pietro; Jenab, Mazda; Andersen, Peter M; Wennberg, Patrik; Wareham, Nicholas; Katzke, Verena; Kaaks, Rudolf; Weiderpass, Elisabete; Peeters, Petra H; Mattiello, Amalia; Pala, Valeria; Barricante, Aurelio; Chirlaque, Maria-Dolores; Travier, Noémie; Travis, Ruth C; Sanchez, Maria-Jose; Pessah-Rasmussen, Hélène; Petersson, Jesper; Tjønneland, Anne; Tumino, Rosario; Quiros, Jose Ramon; Trichopoulou, Antonia; Kyrozis, Andreas; Oikonomidou, Despoina; Masala, Giovanna; Sacerdote, Carlotta; Arriola, Larraitz; Boeing, Heiner; Vigl, Matthaeus; Claver-Chapelon, Francoise; Middleton, Lefkos; Riboli, Elio; Vineis, Paolo

Previous case-control studies have suggested a possible increased risk of Amyotrophic Lateral Sclerosis (ALS) with physical activity (PA), but this association has never been studied in prospective cohort studies. We therefore assessed the association between PA and risk of death from ALS in the

Mental vulnerability, Helicobacter pylori, and incidence of hospital-diagnosed peptic ulcer over 28 years in a population-based cohort

DEFF Research Database (Denmark)

Levenstein, Susan; Jacobsen, Rikke Kart; Rosenstock, Steffen J

2017-01-01

Objective: To examine whether mental vulnerability, an enduring personality characteristic, predicts incident hospital-diagnosed ulcer over three decades. Materials and methods: A population-based cohort study enrolled 3365 subjects with no ulcer history, ages 30–60, in 1982–3. Mental vulnerabili......: A vulnerable personality raises risk for hospital-diagnosed peptic ulcer, in part because of an association with health risk behaviors. Its impact is seen in ‘idiopathic’ and Helicobacter pylori-associated ulcers, and in acute surgical cases.......Objective: To examine whether mental vulnerability, an enduring personality characteristic, predicts incident hospital-diagnosed ulcer over three decades. Materials and methods: A population-based cohort study enrolled 3365 subjects with no ulcer history, ages 30–60, in 1982–3. Mental vulnerability......, Helicobacter pylori IgG antibodies, socioeconomic status, and sleep duration were determined at baseline; non-steroidal antiinflammatory drug use, smoking, leisure time physical activity, and alcohol consumption both at baseline and in 1993–4. Hospital diagnoses of incident ulcer through 2011 were detected...

Long-term oxygen therapy in COPD patients: population-based cohort study on mortality.

Science.gov (United States)

Pavlov, Nikolay; Haynes, Alan Gary; Stucki, Armin; Jüni, Peter; Ott, Sebastian Robert

2018-01-01

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide and is associated with a growing and substantial socioeconomic burden. Long-term oxygen therapy (LTOT), recommended by current treatment guidelines for COPD patients with severe chronic hypoxemia, has shown to reduce mortality in this population. The aim of our study was to assess the standardized mortality ratios of incident and prevalent LTOT users and to identify predictors of mortality. We conducted a 2-year follow-up population-based cohort study comprising all COPD patients receiving LTOT in the canton of Bern, Switzerland. Comparing age- and sex-adjusted standardized mortality ratios, we examined associations between all-cause mortality and patient characteristics at baseline. To avoid immortal time bias, data for incident (receiving LTOT <6 months) and prevalent users were analyzed separately. At baseline, 475 patients (20% incident users, n=93) were receiving LTOT because of COPD (48/100,000 inhabitants). Mortality of incident and prevalent LTOT users was 41% versus 27%, respectively, p <0.007, and standardized mortality ratios were 8.02 (95% CI: 5.64-11.41) versus 5.90 (95% CI: 4.79-7.25), respectively. Type 2 respiratory failure was associated with higher standardized mortality ratios among incident LTOT users (60.57, 95% CI: 11.82-310.45, p =0.038). Two-year mortality rate of COPD patients on incident LTOT was somewhat lower in our study than in older cohorts but remained high compared to the general population, especially in younger patients receiving LTOT <6 months. Type 2 respiratory failure was associated with mortality.

Does perceived stress increase the risk of atrial fibrillation? A population-based cohort study in Denmark

DEFF Research Database (Denmark)

Graff, Simon; Prior, Anders; Fenger-Grøn, Morten

2017-01-01

Background Psychological stress is associated with increased risk of acute cardiovascular diseases, as myocardial infarction. We recently found a higher risk of atrial fibrillation following an acute stressful life event, but it remains unknown whether this also applies to common and less acute....... Conclusions This large population-based cohort study did not reveal a higher risk of atrial fibrillation among persons with a high degree of perceived stress after adjustment for participants' baseline characteristics....

Organochlorine exposures influence on breast cancer risk and survival according to estrogen receptor status: a Danish cohort-nested case-control study

International Nuclear Information System (INIS)

Høyer, Annette P; Jørgensen, Torben; Rank, Fritz; Grandjean, Philippe

2001-01-01

The relationship between breast cancer and organochlorine exposure is controversial and complex. As estrogen receptor positive and negative breast cancer may represent different entities of the disease, this study was undertaken to evaluate organochlorines influence on breast cancer risk and survival according to receptor status. The background material stems from the Copenhagen City Heart Study (Denmark 1976-78). The breast cancer risk was investigated in a cohort nested case-control design including 161 cases and twice as many breast cancer free controls. The cases served as a cohort in the survival analysis. Serum organochlorine concentrations were determined by gaschromotography. The observed increased breast cancer risk associated with exposure to dieldrin derived from women who developed an estrogen receptor negative (ERN) tumor (Odds ratio [OR] I vs. IV quartile, 7.6, 95% confidence interval [95% CI] 1.4-46.1, p-value for linear trend 0.01). Tumors in women with the highest dieldrin serum level were larger and more often spread at the time of diagnosis than ERP tumors. The risk of dying was for the remaining evaluated compounds higher among patients with ERP breast cancer when compared to those with ERN. In the highest quartile of polychlorinated biphenyls (ΣPCB) it was more than 2-fold increased (Relative risk [RR] I vs. IV quartile, 2.5, 95% CI 1.1-5.7), but no dose-response relation was apparent. The results do not suggest that exposure to potential estrogenic organochlorines leads to development of an ERP breast cancer. A possible adverse effect on prognosis of hormone-responsive breast cancers needs to be clarified

High dengue case capture rate in four years of a cohort study in Nicaragua compared to national surveillance data.

Directory of Open Access Journals (Sweden)

Katherine Standish

Full Text Available Dengue is a major public health problem in tropical and subtropical regions; however, under-reporting of cases to national surveillance systems hinders accurate knowledge of disease burden and costs. Laboratory-confirmed dengue cases identified through the Nicaraguan Pediatric Dengue Cohort Study (PDCS were compared to those reported from other health facilities in Managua to the National Epidemiologic Surveillance (NES program of the Nicaraguan Ministry of Health. Compared to reporting among similar pediatric populations in Managua, the PDCS identified 14 to 28 (average 21.3 times more dengue cases each year per 100,000 persons than were reported to the NES. Applying these annual expansion factors to national-level data, we estimate that the incidence of confirmed pediatric dengue throughout Nicaragua ranged from 300 to 1000 cases per 100,000 persons. We have estimated a much higher incidence of dengue than reported by the Ministry of Health. A country-specific expansion factor for dengue that allows for a more accurate estimate of incidence may aid governments and other institutions calculating disease burden, costs, resource needs for prevention and treatment, and the economic benefits of drug and vaccine development.

Elevated plasma vitamin B12 levels and risk of venous thromboembolism among cancer patients: A population-based cohort study

DEFF Research Database (Denmark)

Arendt, Johan Frederik Håkonsen; Farkas, Dora Kormendine; Pedersen, Lars

2017-01-01

INTRODUCTION: Both venous thromboembolism (VTE) and high plasma vitamin B12 levels (cobalamin, Cbl) are markers of occult cancer and aggressive cancer with a poor prognosis. In this population-based cohort study, we assessed VTE risk among cancer patients with high plasma Cbl levels. MATERIALS...

Establishing the Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS): Operationalizing Community-based Research in a Large National Quantitative Study.

Science.gov (United States)

Loutfy, Mona; Greene, Saara; Kennedy, V Logan; Lewis, Johanna; Thomas-Pavanel, Jamie; Conway, Tracey; de Pokomandy, Alexandra; O'Brien, Nadia; Carter, Allison; Tharao, Wangari; Nicholson, Valerie; Beaver, Kerrigan; Dubuc, Danièle; Gahagan, Jacqueline; Proulx-Boucher, Karène; Hogg, Robert S; Kaida, Angela

2016-08-19

Community-based research has gained increasing recognition in health research over the last two decades. Such participatory research approaches are lauded for their ability to anchor research in lived experiences, ensuring cultural appropriateness, accessing local knowledge, reaching marginalized communities, building capacity, and facilitating research-to-action. While having these positive attributes, the community-based health research literature is predominantly composed of small projects, using qualitative methods, and set within geographically limited communities. Its use in larger health studies, including clinical trials and cohorts, is limited. We present the Canadian HIV Women's Sexual and Reproductive Health Cohort Study (CHIWOS), a large-scale, multi-site, national, longitudinal quantitative study that has operationalized community-based research in all steps of the research process. Successes, challenges and further considerations are offered. Through the integration of community-based research principles, we have been successful in: facilitating a two-year long formative phase for this study; developing a novel survey instrument with national involvement; training 39 Peer Research Associates (PRAs); offering ongoing comprehensive support to PRAs; and engaging in an ongoing iterative community-based research process. Our community-based research approach within CHIWOS demanded that we be cognizant of challenges managing a large national team, inherent power imbalances and challenges with communication, compensation and volunteering considerations, and extensive delays in institutional processes. It is important to consider the iterative nature of community-based research and to work through tensions that emerge given the diverse perspectives of numerous team members. Community-based research, as an approach to large-scale quantitative health research projects, is an increasingly viable methodological option. Community-based research has several

Ischemic heart disease in HIV-infected and HIV-uninfected individuals: a population-based cohort study

DEFF Research Database (Denmark)

Obel, N; Thomsen, Henrik F.; Kronborg, G

2007-01-01

BACKGROUND: There are concerns about highly active antiretroviral therapy (HAART) causing a progressive increase in the risk of ischemic heart disease. We examined this issue in a nationwide cohort study of patients with human immunodeficiency virus (HIV) infection and a population-based control...... group. METHODS: We determined the rate of first hospitalization for ischemic heart disease in all Danish patients with HIV infection (3953 patients) from 1 January 1995 through 31 December 2004 and compared this rate with that for 373,856 subjects in a population-based control group. Data on first...... hospitalization for ischemic heart disease and comorbidity were obtained from the Danish National Hospital Registry for all study participants. We used Cox's regression to compute the hospitalization rate ratio as an estimate of relative risk, adjusting for comorbidity. RESULTS: Although the difference...

Developing a dashboard to help measure and achieve the triple aim: a population-based cohort study.

Science.gov (United States)

Seow, Hsien-Yeang; Sibley, Lyn M

2014-08-30

Health system planners aim to pursue the three goals of Triple Aim: 1) reduce health care costs; 2) improve population health; and 3) improve the care experience. Moreover, they also need measures that can reliably predict future health care needs in order to manage effectively the health system performance. Yet few measures exist to assess Triple Aim and predict future needs at a health system level. The purpose of this study is to explore the novel application of a case-mix adjustment method in order to measure and help improve the Triple Aim of health system performance. We applied a case-mix adjustment method to a population-based analysis to assess its usefulness as a measure of health system performance and Triple Aim. The study design was a retrospective, cohort study of adults from Ontario, Canada using administrative databases: individuals were assigned a predicted illness burden score using a case-mix adjustment system from diagnoses and health utilization data in 2008, and then followed forward to assess the actual health care utilization and costs in the following year (2009). We applied the Johns Hopkins Adjusted Clinical Group (ACG) Case-Mix System to categorize individuals into 60 levels of healthcare need, called ACGs. The outcomes were: 1) Number of individuals per ACG; 2) Total system costs per ACG; and 3) Mean cost per person per ACG, which together formed a health system "dashboard". We identified 11.4 million adults. 16.1% were aged 65 or older, 3.2 million (28%) did not use health care services that year, and 45,000 (0.4%) were in the highest acuity ACG category using 12 times more than an average adult. The sickest 1%, 5% and 15% of the population use about 10%, 30% and 50% of total health system costs respectively. The dashboard measures 2 dimensions of Triple Aim: 1) reduced costs: when total system costs per ACG or when average costs per person is reduced; and 2) improved population health: when more people move into healthier rather than

Malignant transformation of Taiwanese patients with oral leukoplakia: A nationwide population-based retrospective cohort study.

Science.gov (United States)

Wang, Tung-Yuan; Chiu, Yu-Wei; Chen, Yi-Tzu; Wang, Yu-Hsun; Yu, Hui-Chieh; Yu, Chuan-Hang; Chang, Yu-Chao

2018-05-01

Oral leukoplakia (OL) is one of the clinically diagnosed oral potentially malignant disorders (OPMDs) with an increased risk of oral cancer development. In this study, we investigated the malignant transformation of OL in Taiwanese population. A retrospective cohort study was analyzed from Taiwan's National Health Insurance Research Database. A comparison cohort was randomly frequency-matched with the OL cohort according to age, sex, and index year. Oral submucous fibrosis (OSF) and oral lichen planus (OLP) were further stratified to evaluate the possible synergistic effects for OL-associated malignant transformation. In this cohort, 102 (5.374%) of 1898 OL patients were observed to transform into oral cancer. The malignant transformation rate was 26.40-fold in the OL cohort than in the comparison cohort after adjustment (95% confidence intervals 18.46-37.77). To further stratify with OSF and OLP, OL with OSF (58.38; 95% confidence intervals 34.61-98.50) and OL with OLP (36.88; 95% confidence intervals 8.90-152.78) had higher risk of malignant transformation rate than OL alone (27.01; 95% confidence intervals 18.91-38.59). The Kaplan-Meier plot revealed the free of malignant transformation rate was significant over the 13 years follow-up period (log-rank test, p < 0.001). OL patients exhibited a significantly higher risk of malignant transformation than those without OL. In addition, both OSF and OLP could enhance malignant transformation in patients with OL. However, further studies are required to identify the histopathological and clinical parameters in the pathogenesis of malignant transformation among OPMDs. Copyright © 2018. Published by Elsevier B.V.

The Korea Nurses' Health Study: A Prospective Cohort Study.

Science.gov (United States)

Kim, Oksoo; Ahn, Younjhin; Lee, Hea-Young; Jang, Hee Jung; Kim, Sue; Lee, Jung Eun; Jung, Heeja; Cho, Eunyoung; Lim, Joong-Yeon; Kim, Min-Ju; Willett, Walter C; Chavarro, Jorge E; Park, Hyun-Young

2017-08-01

The Korea Nurses' Health Study (KNHS) is a prospective cohort study of female nurses, focusing on the effects of occupational, environmental, and lifestyle risk factors on the health of Korean women. Female registered nurses aged 20-45 years and living in the Republic of Korea were invited to join the study, which began in July 2013. They were asked to complete a web-based baseline survey. The study protocols and questionnaires related to the KNHS are based on the Nurses' Health Study 3 (NHS3) in the United States, although they were modified to reflect the Korean lifestyle. Participants were asked about demographic, lifestyle factors, disease history, occupational exposure, reproductive factors, and dietary habits during their adolescence: Follow-up questionnaires were/will be completed at 6-8 month intervals after the baseline survey. If a participant became pregnant, she answered additional questionnaires containing pregnancy-related information. Among 157,569 eligible female nurses, 20,613 (13.1%) completed the web-based baseline questionnaire. The mean age of the participants was 29.4 ± 5.9 years, and more than half of them were in their 20s. Eighty-eight percent of the participants had worked night shifts as a nurse (mean, 5.3 ± 4.3 nights per month). Approximately 80% of the participants had a body mass index below 23 kg/m 2 . Gastrointestinal diseases were the most prevalent health issues (25.9%). The findings from this prospective cohort study will help to identify the effects of lifestyle-related and occupational factors on reproductive health and development of chronic diseases in Korean women.

Epilepsy Among Children and Adolescents with Autism Spectrum Disorders: A Population-Based Study

Science.gov (United States)

Jokiranta, Elina; Sourander, Andre; Suominen, Auli; Timonen-Soivio, Laura; Brown, Alan S.; Sillanpää, Matti

2014-01-01

The present population-based study examines associations between epilepsy and autism spectrum disorders (ASD). The cohort includes register data of 4,705 children born between 1987 and 2005 and diagnosed as cases of childhood autism, Asperger's syndrome or pervasive developmental disorders--not otherwise specified. Each case was matched to four…

Incense use and respiratory tract carcinomas: a prospective cohort study

DEFF Research Database (Denmark)

Yuan, J.M.; Wang, R.; Koh, W.P.

2008-01-01

of cancer and ages 45 to 74 years completed a comprehensive interview regarding living conditions and dietary and lifestyle factors. Through linkage to population-based registries, the cohort was followed through 2005 and cancer occurrence determined. The relative risk for these cancers associated......BACKGROUND: Incense use is an integral part of daily life in large parts of Asia. The burning of incense is a powerful producer of particulate matter and the smoke contains a multitude of well-characterized carcinogens. However, to the authors' knowledge, no convincing association has been reported...... between exposure to incense smoke and the development of cancer. Therefore, the relation between incense use and the risk of respiratory tract carcinomas was analyzed in a prospective cohort study. METHODS: Between 1993 and 1998, a population-based cohort of 61,320 Singapore Chinese who were free...

A Review of Case-Based Learning Practices in an Online MBA Program: A Program-Level Case Study

Science.gov (United States)

Lee, Seung-hee; Lee, Jieun; Liu, Xiaojing; Bonk, Curt J.; Magjuka, Richard J.

2009-01-01

This study examines how a case-based learning approach was used and facilitated in online business education. Perceptions of students and instructors regarding the practices of case-based learning in online environments are explored in terms of instructional design, facilitation, and technology support. This study finds case-based learning to be a…

Nonsteroidal anti-inflammatory drugs and the risk of developing breast cancer in a population-based prospective cohort study in Washington County, MD.

Science.gov (United States)

Gallicchio, Lisa; Visvanathan, Kala; Burke, Alyce; Hoffman, Sandra C; Helzlsouer, Kathy J

2007-07-01

The objective of this study was to examine the association between nonsteroidal anti-inflammatory drug (NSAID) use and the development of breast cancer, and to assess whether this association differed by estrogen receptor (ER) subtype. Data were analyzed from 15,651 women participating in CLUE II, a cohort study initiated in 1989 in Washington County, MD. Medication data were collected at baseline in 1989 and in 1996. Incident cases of invasive breast cancer occurring from baseline to March 27, 2006 were identified through linkage of cohort participants with the Washington County Cancer Registry and the Maryland State Cancer Registry. Cox proportional hazards modeling was used to calculate the risk ratios (RR) and 95% confidence intervals (95% CI) for breast cancer associated with medication use. Among women in the CLUE II cohort, 418 invasive breast cancer cases were identified during the follow-up period. The results showed that self-reported use of NSAIDs in both 1989 and in 1996 was associated with a 50% reduction in the risk of developing invasive breast cancer compared with no NSAID use in either 1989 or 1996 (RR = 0.50; 95% CI 0.28, 0.91). The protective association between NSAID use and the risk of developing breast cancer was consistent among ER-positive and ER-negative breast cancers, although only the RR for ER-positive breast cancer was statistically significant. Overall, findings from this study indicate that NSAID use is associated with a decrease in breast cancer risk and that the reduction in risk is similar for ER-positive and ER-negative tumors.

A Java-Web-Based-Learning Methodology, Case Study ...

African Journals Online (AJOL)

A Java-Web-Based-Learning Methodology, Case Study : Waterborne diseases. The recent advances in web technologies have opened new opportunities for computer-based-education. One can learn independently of time and place constraints, and have instantaneous access to relevant updated material at minimal cost.

Analyzing age-specific genetic effects on human extreme age survival in cohort-based longitudinal studies

DEFF Research Database (Denmark)

Tan, Qihua; Jacobsen, Rune; Sørensen, Mette

2013-01-01

The analysis of age-specific genetic effects on human survival over extreme ages is confronted with a deceleration pattern in mortality that deviates from traditional survival models and sparse genetic data available. As human late life is a distinct phase of life history, exploring the genetic...... effects on extreme age survival can be of special interest to evolutionary biology and health science. We introduce a non-parametric survival analysis approach that combines population survival information with individual genotype data in assessing the genetic effects in cohort-based longitudinal studies...

Retrospective benzene exposure assessment for a multi-center case-cohort study of benzene-exposed workers in China.

Science.gov (United States)

Portengen, Lützen; Linet, Martha S; Li, Gui-Lan; Lan, Qing; Dores, Graça M; Ji, Bu-Tian; Hayes, Richard B; Yin, Song-Nian; Rothman, Nathaniel; Vermeulen, Roel

2016-01-01

Quality of exposure assessment has been shown to be related to the ability to detect risk of lymphohematopoietic disorders in epidemiological investigations of benzene, especially at low levels of exposure. We set out to build a statistical model for reconstructing exposure levels for 2898 subjects from 501 factories that were part of a nested case-cohort study within the NCI-CAPM cohort of more than 110,000 workers. We used a hierarchical model to allow for clustering of measurements by factory, workshop, job, and date. To calibrate the model we used historical routine monitoring data. Measurements below the limit of detection were accommodated by constructing a censored data likelihood. Potential non-linear and industry-specific time-trends and predictor effects were incorporated using regression splines and random effects. A partial validation of predicted exposures in 2004/2005 was performed through comparison with full-shift measurements from an exposure survey in facilities that were still open. Median cumulative exposure to benzene at age 50 for subjects that ever held an exposed job (n=1175) was 509 mg/m(3) years. Direct comparison of model estimates with measured full-shift personal exposure in the 2004/2005 survey showed moderate correlation and a potential downward bias at low (<1 mg/m(3)) exposure estimates. The modeling framework enabled us to deal with the data complexities generally found in studies using historical exposure data in a comprehensive way and we therefore expect to be able to investigate effects at relatively low exposure levels.

Tuberculosis screening and follow-up of asylum seekers in Norway: a cohort study

Directory of Open Access Journals (Sweden)

Garåsen Helge

2009-05-01

Full Text Available Abstract Background About 80% of new tuberculosis cases in Norway occur among immigrants from high incidence countries. On arrival to the country all asylum seekers are screened with Mantoux test and chest x-ray aimed to identify cases of active tuberculosis and, in the case of latent tuberculosis, to offer follow-up or prophylactic treatment. We assessed a national programme for screening, treatment and follow-up of tuberculosis infection and disease in a cohort of asylum seekers. Methods Asylum seekers ≥ 18 years who arrived at the National Reception Centre from January 2005 to June 2006, were included as the total cohort. Those with a Mantoux test ≥ 6 mm or positive x-ray findings were included in a study group for follow-up. Data were collected from public health authorities in the municipality to where the asylum seekers had moved, and from hospital based internists in case they had been referred to specialist care. Individual subjects included in the study group were matched with the Norwegian National Tuberculosis Register which receive reports of everybody diagnosed with active tuberculosis, or who had started treatment for latent tuberculosis. Results The total cohort included 4643 adult asylum seekers and 97.5% had a valid Mantoux test. At least one inclusion criterion was fulfilled by 2237 persons. By end 2007 municipal public health authorities had assessed 758 (34% of them. Altogether 328 persons had been seen by an internist. Of 314 individuals with positive x-rays, 194 (62% had seen an internist, while 86 of 568 with Mantoux ≥ 15, but negative x-rays (16% were also seen by an internist. By December 31st 2006, 23 patients were diagnosed with tuberculosis (prevalence 1028/100 000 and another 11 were treated for latent infection. Conclusion The coverage of screening was satisfactory, but fewer subjects than could have been expected from the national guidelines were followed up in the community and referred to an internist. To

Methodological aspects of the 1993 Pelotas (Brazil) Birth Cohort Study

Science.gov (United States)

Victora, Cesar Gomes; Araújo, Cora Luiza Pavin; Menezes, Ana Maria Batista; Hallal, Pedro Curi; Vieira, Maria de Fátima; Neutzling, Marilda Borges; Gonçalves, Helen; Valle, Neiva Cristina; Lima, Rosangela Costa; Anselmi, Luciana; Behague, Dominique; Gigante, Denise Petrucci; Barros, Fernando Celso

2010-01-01

This paper describes the main methodological aspects of a cohort study, with emphasis on its recent phases, which may be relevant to investigators planning to carry out similar studies. In 1993, a population based study was launched in Pelotas, Southern Brazil. All 5,249 newborns delivered in the city’s hospitals were enrolled, and sub-samples were visited at the ages of one, three and six months and of one and four years. In 2004-5 it was possible to trace 87.5% of the cohort at the age of 10-12 years. Sub-studies are addressing issues related to oral health, psychological development and mental health, body composition, and ethnography. Birth cohort studies are essential for investigating the early determinants of adult disease and nutritional status, yet few such studies are available from low and middle-income countries where these determinants may differ from those documented in more developed settings. PMID:16410981

No evidence of a causal relationship between hypothyroidism and glaucoma: A Danish nationwide register-based cohort study.

Science.gov (United States)

Thvilum, Marianne; Brandt, Frans; Brix, Thomas Heiberg; Hegedüs, Laszlo

2018-01-01

An interrelationship between hypothyroidism and glaucoma, due to a shared autoimmune background or based on deposition of mucopolysaccharides in the trabecular meshwork in the eye, has been suggested but is at present unsubstantiated. Therefore, our objective was to investigate, at a nationwide and population-based level, whether there is such an association. Observational cohort study using record-linkage data from nationwide Danish health registers. 121,799 individuals diagnosed with a first episode of hypothyroidism were identified and were matched with 4 non-hypothyroid controls according to age and sex. Prevalence of glaucoma was recorded and cases and controls were followed over a mean of 7.1 years (range 0-17). Logistic and Cox regression models were used to assess the risk of glaucoma before and after the diagnosis of hypothyroidism, respectively. Overall, we found a higher prevalence of glaucoma in subjects with hypothyroidism as compared to controls (4.6% vs. 4.3%, p glaucoma [1.09; 95% confidence interval (CI): 1.04-1.13]. Based on the Cox regression model, there was no increased risk of glaucoma after the diagnosis of hypothyroidism [hazard ratio (HR) 1.00; 95% CI: 0.96-1.06], and the HR decreased further after adjusting for pre-existing co-morbidity (0.88; 95% CI: 0.84-0.93). There was an increased risk of glaucoma before but not after the diagnosis of hypothyroidism, suggesting that screening for glaucoma in hypothyroid individuals is unwarranted.

Impact of preoperative chronic renal failure on liver transplantation: a population-based cohort study

Science.gov (United States)

Chung, Peter Chi-Ho; Chen, Hsiu-Pin; Lin, Jr-Rung; Liu, Fu-Chao; Yu, Huang-Ping

2016-01-01

Purpose The purpose of this study was to assess whether preoperative chronic renal failure (CRF) affects the rates of postoperative complications and survival after liver transplantation. Methods This population-based retrospective cohort study included 2,931 recipients of liver transplantation performed between 1998 and 2012, enrolled from the Taiwan National Health Insurance Research Database. Patients were divided into two groups, based on the presence or absence of preoperative CRF. Results The overall estimated survival rate of liver transplantation recipients (LTRs) with preoperative CRF was significantly lower than that of patients without preoperative CRF (P=0.0085). There was no significant difference between the groups in terms of duration of intensive care unit stay, total hospital stay, bacteremia, postoperative bleeding, and pneumonia during hospitalization. Long-term adverse effects, including cerebrovascular disease and coronary heart disease, were not different between patients with versus without CRF. Conclusion These findings suggest that LTRs with preoperative CRF have a higher rate of mortality. PMID:28008264

Risk of Nongenitourinary Cancers in Patients With Spinal Cord Injury: A Population-based Cohort Study.

Science.gov (United States)

Kao, Chia-Hong; Sun, Li-Min; Chen, Yueh-Sheng; Lin, Cheng-Li; Liang, Ji-An; Kao, Chia-Hung; Weng, Ming-Wei

2016-01-01

Little information is available regarding the risk of nongenitourinary (GU) cancers in patients with spinal cord injury (SCI). The authors conducted a nationwide population-based study to investigate whether a higher risk of non-GU cancer is seen among patients with SCI.Data retrieved from the National Health Insurance Research Database of Taiwan were used in this study. A total of 41,900 patients diagnosed with SCI between 2000 and 2011 were identified from the National Health Insurance Research Database and comprised the SCI cohort. Each of these patients was randomly frequency matched with 4 people from the general population (without SCI) according to age, sex, comorbidities, and index year. Cox proportional hazards regression analysis was used to calculate adjusted hazard ratios and 95% confidence intervals and determine how SCI affected non-GU cancer risk.No significant difference in overall non-GU cancer risk was observed between the SCI and control groups. The patients with SCI exhibited a significantly higher risk of developing esophageal, liver, and hematologic malignancies compared with those without SCI. By contrast, the SCI cohort had a significantly lower risk of colorectal cancer compared with the non-SCI cohort (adjusted hazard ratio = 0.80, 95% confidence interval = 0.69-0.93). Additional stratified analyses by sex, age, and follow-up duration revealed various correlations between SCI and non-GU cancer risk.The patients with SCI exhibited higher risk of esophageal, liver, and hematologic malignancies but a lower risk of colorectal cancer compared with those without SCI. The diverse patterns of cancer risk among the patients with SCI may be related to the complications of chronic SCI.

Immunological and cardiometabolic risk factors in the prediction of type 2 diabetes and coronary events: MONICA/KORA Augsburg case-cohort study.

Directory of Open Access Journals (Sweden)

Christian Herder

Full Text Available BACKGROUND: This study compares inflammation-related biomarkers with established cardiometabolic risk factors in the prediction of incident type 2 diabetes and incident coronary events in a prospective case-cohort study within the population-based MONICA/KORA Augsburg cohort. METHODS AND FINDINGS: Analyses for type 2 diabetes are based on 436 individuals with and 1410 individuals without incident diabetes. Analyses for coronary events are based on 314 individuals with and 1659 individuals without incident coronary events. Mean follow-up times were almost 11 years. Areas under the receiver-operating characteristic curve (AUC, changes in Akaike's information criterion (ΔAIC, integrated discrimination improvement (IDI and net reclassification index (NRI were calculated for different models. A basic model consisting of age, sex and survey predicted type 2 diabetes with an AUC of 0.690. Addition of 13 inflammation-related biomarkers (CRP, IL-6, IL-18, MIF, MCP-1/CCL2, IL-8/CXCL8, IP-10/CXCL10, adiponectin, leptin, RANTES/CCL5, TGF-β1, sE-selectin, sICAM-1; all measured in nonfasting serum increased the AUC to 0.801, whereas addition of cardiometabolic risk factors (BMI, systolic blood pressure, ratio total/HDL-cholesterol, smoking, alcohol, physical activity, parental diabetes increased the AUC to 0.803 (ΔAUC [95% CI] 0.111 [0.092-0.149] and 0.113 [0.093-0.149], respectively, compared to the basic model. The combination of all inflammation-related biomarkers and cardiometabolic risk factors yielded a further increase in AUC to 0.847 (ΔAUC [95% CI] 0.044 [0.028-0.066] compared to the cardiometabolic risk model. Corresponding AUCs for incident coronary events were 0.807, 0.825 (ΔAUC [95% CI] 0.018 [0.013-0.038] compared to the basic model, 0.845 (ΔAUC [95% CI] 0.038 [0.028-0.059] compared to the basic model and 0.851 (ΔAUC [95% CI] 0.006 [0.003-0.021] compared to the cardiometabolic risk model, respectively. CONCLUSIONS: Inclusion of multiple

A Canadian naturalistic study of a community-based cohort treated for bipolar disorder

Directory of Open Access Journals (Sweden)

Chandresena Ranjith

2010-03-01

Full Text Available Abstract Background Bipolar illness is associated with significant psychosocial morbidity and health resource utilization. Second generation antipsychotics, used alone or in combination with mood stabilizers are effective in treating acute mania in community settings. This study was designed to compare the change in clinical parameters and resource utilization at one month in a group of patients who required treatment intervention for exacerbation of mania. The clinical response at one year was also evaluated. Methods 496 patients were enrolled at 75 psychiatric practices across Canada. The Olanzapine cohort (n = 287 included patients who had olanzapine added to their medication regimen or the dose of olanzapine increased. The Other cohort (n = 209 had a medication other than olanzapine added or the dose adjusted. Changes from baseline in the Young Mania Rating Scale (YMRS, Montgomery Asberg Depression Rating Scale, Beck Anxiety Inventory and SF-12 Health Survey were compared at one month using ANCOVA. Categorical variables at one month for health resource utilization, employment status, abuse/dependency, and the number of suicide attempts were compared using Fisher's Exact test. Patients were followed for one year and a subgroup was evaluated. Results At one month, patients in the Olanzapine cohort recorded a mean reduction in the YMRS of 11.5, significantly greater than the mean reduction in the Other cohort of 9.7 (ANCOVA P = 0.002. The Olanzapine cohort was significantly improved compared to the Other cohort on the scales for depression and anxiety and did not experience the deterioration in physical functioning seen in the Other cohort. No significant differences were detected in health-related quality-of-life measures, employment status, drug abuse/dependency, number of suicide attempts, mental functioning, emergency room visits or inpatient psychiatric hospitalizations. In a subgroup treated for 12 months with a single second generation

Risk of Cerebrovascular Accidents and Ischemic Heart Disease in Cutaneous Lupus Erythematosus: A Population-Based Cohort Study.

Science.gov (United States)

Singh, Abha G; Crowson, Cynthia S; Singh, Siddharth; Denis, Mark; Davis, P; Maradit-Kremers, Hilal; Matteson, Eric L; Chowdhary, Vaidehi R

2016-11-01

It is unclear whether isolated cutaneous lupus erythematosus (CLE) affects cardiovascular risk. We estimated the cumulative incidence and mortality of cardiovascular diseases in a population-based CLE cohort and compared the risk with a matched non-CLE cohort. All incident cases of CLE in Olmsted County, Minnesota, between 1965 and 2005 were followed until December 2013. The cumulative incidence of cerebrovascular accidents (CVAs [including stroke and transient ischemic attack]), ischemic heart disease (IHD [including coronary artery disease, myocardial infarction, and angina pectoris]), heart failure, and peripheral arterial disease (PAD) was derived and compared to an age-, sex-, and calendar year-matched non-CLE cohort using Cox models. There were 155 patients with CLE (mean ± SD age at diagnosis 48 ± 16 years, 65% female, mean ± SD BMI 26.3 ± 7.1 kg/m 2 , 40% smokers, 9% with diabetes mellitus). During a median followup of 14.6 years, 41 CLE patients had cardiovascular events (15 patients with CVAs, 32 patients with IHD), with a 20-year cumulative incidence of 31.6%. As compared to non-CLE subjects, the risk of CVAs (smoking-adjusted hazard ratio [HR] 2.97 [95% confidence interval (95% CI) 1.13-7.78]) and PAD (HR 2.06 [95% CI 0.99-4.32]) was increased in patients with CLE, but the risk of IHD was not increased (HR 0.94 [95% CI 0.57-1.54]). There was no increase in cardiovascular mortality (HR 1.68 [95% CI 0.76-3.75]). The magnitude of risk for any cardiovascular outcome was not significantly influenced by the extent of cutaneous involvement. CLE may be associated with an increased risk of CVAs and PAD, but not IHD. Factors contributing to increased CVA risk in patients with CLE merit evaluation. © 2016, American College of Rheumatology.

The Use of Hypnotics and Mortality--A Population-Based Retrospective Cohort Study.

Directory of Open Access Journals (Sweden)

Tzuo-Yun Lan

Full Text Available Sleep disorders, especially chronic insomnia, have become major health problem worldwide and, as a result, the use of hypnotics is steadily increasing. However, few studies with a large sample size and long-term observation have been conducted to investigate the relationship between specific hypnotics and mortality.We conducted this retrospective cohort study using data from the National Health Insurance Research Database in Taiwan. Information from claims data including basic characteristics, the use of hypnotics, and survival from 2000 to 2009 for 1,320,322 individuals were included. The use of hypnotics was divided into groups using the defined daily dose and the cumulative length of use. Hazard ratios (HRs were calculated from a Cox proportional hazards model, with two different matching techniques to examine the associations.Compared to the non-users, both users of benzodiazepines (HR = 1.81; 95% confidence interval [CI] = 1.78-1.85 and mixed users (HR = 1.44; 95% CI = 1.42-1.47 had a higher risk of death, whereas the users of other non-benzodiazepines users showed no differences. Zolpidem users (HR = 0.73; 95% CI = 0.71-0.75 exhibited a lower risk of mortality in the adjusted models. This pattern remained similar in both matching techniques. Secondary analysis indicated that zolpidem users had a reduced risk of major cause-specific mortality except cancer, and that this protective effect was dose-responsive, with those using for more than 1 year having the lowest risk.The effects of different types of hypnotics on mortality were diverse in this large cohort with long-term follow-up based on representative claims data in Taiwan. The use of zolpidem was associated with a reduced risk of mortality.

The Use of Hypnotics and Mortality--A Population-Based Retrospective Cohort Study.

Science.gov (United States)

Lan, Tzuo-Yun; Zeng, Ya-Fang; Tang, Gau-Jun; Kao, Hui-Chuan; Chiu, Hsien-Jane; Lan, Tsuo-Hung; Ho, Hsiao-Feng

2015-01-01

Sleep disorders, especially chronic insomnia, have become major health problem worldwide and, as a result, the use of hypnotics is steadily increasing. However, few studies with a large sample size and long-term observation have been conducted to investigate the relationship between specific hypnotics and mortality. We conducted this retrospective cohort study using data from the National Health Insurance Research Database in Taiwan. Information from claims data including basic characteristics, the use of hypnotics, and survival from 2000 to 2009 for 1,320,322 individuals were included. The use of hypnotics was divided into groups using the defined daily dose and the cumulative length of use. Hazard ratios (HRs) were calculated from a Cox proportional hazards model, with two different matching techniques to examine the associations. Compared to the non-users, both users of benzodiazepines (HR = 1.81; 95% confidence interval [CI] = 1.78-1.85) and mixed users (HR = 1.44; 95% CI = 1.42-1.47) had a higher risk of death, whereas the users of other non-benzodiazepines users showed no differences. Zolpidem users (HR = 0.73; 95% CI = 0.71-0.75) exhibited a lower risk of mortality in the adjusted models. This pattern remained similar in both matching techniques. Secondary analysis indicated that zolpidem users had a reduced risk of major cause-specific mortality except cancer, and that this protective effect was dose-responsive, with those using for more than 1 year having the lowest risk. The effects of different types of hypnotics on mortality were diverse in this large cohort with long-term follow-up based on representative claims data in Taiwan. The use of zolpidem was associated with a reduced risk of mortality.

Costs and Efficiency of Online and Offline Recruitment Methods: A Web-Based Cohort Study

Science.gov (United States)

Riis, Anders H; Hatch, Elizabeth E; Wise, Lauren A; Nielsen, Marie G; Rothman, Kenneth J; Toft Sørensen, Henrik; Mikkelsen, Ellen M

2017-01-01

Background The Internet is widely used to conduct research studies on health issues. Many different methods are used to recruit participants for such studies, but little is known about how various recruitment methods compare in terms of efficiency and costs. Objective The aim of our study was to compare online and offline recruitment methods for Internet-based studies in terms of efficiency (number of recruited participants) and costs per participant. Methods We employed several online and offline recruitment methods to enroll 18- to 45-year-old women in an Internet-based Danish prospective cohort study on fertility. Offline methods included press releases, posters, and flyers. Online methods comprised advertisements placed on five different websites, including Facebook and Netdoktor.dk. We defined seven categories of mutually exclusive recruitment methods and used electronic tracking via unique Uniform Resource Locator (URL) and self-reported data to identify the recruitment method for each participant. For each method, we calculated the average cost per participant and efficiency, that is, the total number of recruited participants. Results We recruited 8252 study participants. Of these, 534 were excluded as they could not be assigned to a specific recruitment method. The final study population included 7724 participants, of whom 803 (10.4%) were recruited by offline methods, 3985 (51.6%) by online methods, 2382 (30.8%) by online methods not initiated by us, and 554 (7.2%) by other methods. Overall, the average cost per participant was €6.22 for online methods initiated by us versus €9.06 for offline methods. Costs per participant ranged from €2.74 to €105.53 for online methods and from €0 to €67.50 for offline methods. Lowest average costs per participant were for those recruited from Netdoktor.dk (€2.99) and from Facebook (€3.44). Conclusions In our Internet-based cohort study, online recruitment methods were superior to offline methods in terms

Vegetable and fruit consumption and prostate cancer risk: A cohort study in the Netherlands

NARCIS (Netherlands)

Schuurman, A.G.; Goldbohm, R.A.; Dorant, E.; Brandt, P.A. van den

1998-01-01

The association between 21 vegetables and eight fruits and prostate cancer risk was assessed in the Netherlands Cohort Study among 58,279 men of ages 55-69 years at baseline in 1986. After 6.3 years of follow-up, 610 cases with complete vegetable data and 642 cases with complete fruit data were

The natural course of eczema from birth to age 7 years and the association with asthma and allergic rhinitis: a population-based birth cohort study.

Science.gov (United States)

Shen, Chian-Yin; Lin, Ming-Chih; Lin, Heng-Kuei; Lin, Ching-Heng; Fu, Lin-Shien; Fu, Yun-Chin

2013-01-01

Although "atopic march" is a popular concept, the relationship between eczema and subsequent asthma is far from clear. However, some cohort studies have shown the possibility of two different allergic phenotypes in those who present with early eczema in terms of their persistency. We checked the cohort data from 308,849 children born in 2000 in Taiwan, to evaluate the different courses of eczema and their relationships to subsequent asthma and allergic rhinitis (AR) at age 7 years. We examined the age prevalence of eczema, asthma, and AR up to 7 years of age. We grouped all cases according to their course of eczema, as well as wheezing, and determined the rates of asthma and AR at age 7 years. We checked the adjusted risk factors by multiple logistic regression model. We also examined the distributions of wheezing types in different eczema groups. We found the "atopic march" pattern of allergic diseases based on their age prevalence. Early eczema was associated with asthma and AR at the age of 7 years. Those with eczema symptoms persisting after 36 months of age had a higher risk than those with transient eczema. Early wheeze also contributed to asthma and AR later in childhood. In addition, late-onset eczema had a completely different wheeze distribution compared with other groups and also had a higher risk for asthma and AR than transient eczema. In conclusion, different eczema phenotypes could be found in this population-based cohort. This article emphasizes the special attention to the persistency and late-onset eczema in clinical practice.

Risk of prostate and bladder cancers in patients with spinal cord injury: a population-based cohort study.

Science.gov (United States)

Lee, Wen-Yuan; Sun, Li-Min; Lin, Cheng-Li; Liang, Ji-An; Chang, Yen-Jung; Sung, Fung-Chang; Kao, Chia-Hung

2014-01-01

To evaluate the risk of prostate and bladder cancers in patients with spinal cord injury (SCI). We used data obtained from the National Health Insurance system of Taiwan for this study. The SCI cohort contained 54,401 patients with SCI, and each patient was randomly frequency matched with 4 people from the general population (without SCI) based on age, sex, and index date. Incidence rates, SCI cohort to non-SCI cohort rate ratios, and hazard ratios were measured to evaluate the cancer risks. Patients with SCI showed a significantly lower risk of developing prostate cancer compared with subjects without SCI (adjusted hazard ratio = 0.73; 95% confidence interval = 0.59, 0.90), after accounting for the competing risk of death. No significant difference in the risk of bladder cancer emerged between the SCI and control groups. Further analyses found a higher spinal level of SCI tended to predict a lower risk for prostate cancer. Patients with SCI incurred a lower risk for prostate cancer compared with people without SCI. The risk for bladder cancer did not differ between people with or without SCI. Copyright © 2014 Elsevier Inc. All rights reserved.

Risk of psychiatric disorders following polycystic ovary syndrome: a nationwide population-based cohort study.

Directory of Open Access Journals (Sweden)

Jeng-Hsiu Hung

Full Text Available BACKGROUND: Polycystic ovary syndrome (PCOS is one of the most common endocrine disorders among women of reproductive age. A higher prevalence of psychiatric comorbidities, including depressive disorder, anxiety disorder, and bipolar disorder has been proved in patients with PCOS. However, a clear temporal causal relationship between PCOS and psychiatric disorders has not been well established. OBJECTIVE: We explored the relationship between PCOS and the subsequent development of psychiatric disorders including schizophrenia, bipolar disorder, depressive disorder, anxiety disorder, and sleep disorder. METHODS: We identified patients who were diagnosed with PCOS by an obstetrician-gynecologist in the Taiwan National Health Insurance Research Database. A comparison cohort was constructed of patients without PCOS who were matched according to age and sex. The occurrence of subsequent new-onset psychiatric disorders was evaluated in both cohorts based on diagnoses made by psychiatrists. RESULTS: The PCOS cohort consisted of 5431 patients, and the comparison cohort consisted of 21,724 matched control patients without PCOS. The incidence of depressive disorder (hazard ratio [HR] 1.296, 95% confidence interval [CI] 1.084-.550, anxiety disorder (HR 1.392, 95% CI 1.121-1.729, and sleep disorder (HR 1.495, 95% CI 1.176-1.899 were higher among the PCOS patients than among the patients in the comparison cohort. In addition, a higher incidence of newly diagnosed depressive disorder, anxiety disorder, and sleep disorder remained significantly increased in all of the stratified follow-up durations (0-1, 1-5, ≥5 y. CONCLUSIONS: PCOS might increase the risk of subsequent newly diagnosed depressive disorder, anxiety disorder, and sleep disorder. The risk of newly diagnosed bipolar disorder, which has often been reported in the literature to be comorbid with PCOS, was not significantly elevated.

Effect of periodontitis on the development of osteoporosis: results from a nationwide population-based cohort study (2003-2013).

Science.gov (United States)

Choi, Jung-Kyu; Kim, Young-Taek; Kweon, Hye-In; Park, Eun-Cheol; Choi, Seong-Ho; Lee, Jae-Hong

2017-09-11

The prevalence of osteoporosis associated with the aging process is anticipated to increase along with the rising aging population. Periodontitis that the most common chronic infections of humankind is considered the risk factor for osteoporosis. The aim of this study was to identify the association between osteoporosis and periodontitis using a population-based cohort. The case group was defined as patients diagnosed with periodontitis and treated with subgingival curettage, root conditioning, periodontal flap operation, bone grafting for alveolar bone defects, and guided tissue regeneration. Case and control groups matched for gender, age, household income, type of social security, disability, and residential area were generated. A Cox proportional hazard model was constructed to examine the difference in the development of osteoporosis between the case and control groups. The final sample included 13,464 participants. The incidence of osteoporosis was 1.1% in males and 15.8% in females during a 10-year period. The risk factors for osteoporosis in males were increasing age and Charlson Comorbidity Index score. Periodontitis was not associated with the development of osteoporosis in males. The risk factors for osteoporosis in females were increasing age, body mass index, Charlson Comorbidity Index score, diabetes, and periodontitis. Women with periodontitis were more likely to also develop osteoporosis (HR: 1.22, 95% CI: 1.01-1.48). Periodontitis has an effect on the development of osteoporosis in females. Managing good teeth is required for the prevention and delay of osteoporosis. This includes dental examinations, regular cleanings and gum treatment.

Global incidence and case fatality rate of pulmonary embolism following major surgery: a protocol for a systematic review and meta-analysis of cohort studies.

Science.gov (United States)

Temgoua, Mazou N; Tochie, Joel Noutakdie; Noubiap, Jean Jacques; Agbor, Valirie Ndip; Danwang, Celestin; Endomba, Francky Teddy A; Nkemngu, Njinkeng J

2017-12-04

Pulmonary embolism (PE) is a life-threatening condition common after major surgery. Although the high incidence (0.3-30%) and mortality rate (16.9-31%) of PE in patients undergoing major surgical procedures is apparent from findings of contemporary observational studies, there is a lack of a summary and meta-analysis data on the epidemiology of postoperative PE in this same regard. Hence, we propose to conduct the first systematic review to summarise existing data on the global incidence, determinants and case fatality rate of PE following major surgery. Electronic databases including MEDLINE, EMBASE, SCOPUS, WHO global health library (including LILACS), Web of Science and Google scholar from inception to April 30, 2017, will be searched for cohort studies reporting on the incidence, determinants and case fatality rate of PE occurring after major surgery. Data from grey literature will also be assessed. Two investigators will independently perform study selection and data extraction. Included studies will be evaluated for risk of bias. Appropriate meta-analytic methods will be used to pool incidence and case fatality rate estimates from studies with identical features, globally and by subgroups of major surgical procedures. Random-effects and risk ratio with 95% confidence interval will be used to summarise determinants and predictors of mortality of PE in patients undergoing major surgery. This systematic review and meta-analysis will provide the most up-to-date epidemiology of PE in patients undergoing major surgery to inform health authorities and identify further research topics based on the remaining knowledge gaps. PROSPERO CRD42017065126.

Multicenter cohort association study of SLC2A1 single nucleotide polymorphisms and age-related macular degeneration

Science.gov (United States)

Baas, Dominique C.; Ho, Lintje; Tanck, Michael W.T.; Fritsche, Lars G.; Merriam, Joanna E.; van het Slot, Ruben; Koeleman, Bobby P.C.; Gorgels, Theo G.M.F.; van Duijn, Cornelia M.; Uitterlinden, André G.; de Jong, Paulus T.V.M.; Hofman, Albert; ten Brink, Jacoline B.; Vingerling, Johannes R.; Klaver, Caroline C.W.; Dean, Michael; Weber, Bernhard H. F.; Allikmets, Rando; Hageman, Gregory S.

2012-01-01

Purpose Age-related macular degeneration (AMD) is a major cause of blindness in older adults and has a genetically complex background. This study examines the potential association between single nucleotide polymorphisms (SNPs) in the glucose transporter 1 (SLC2A1) gene and AMD. SLC2A1 regulates the bioavailability of glucose in the retinal pigment epithelium (RPE), which might influence oxidative stress–mediated AMD pathology. Methods Twenty-two SNPs spanning the SLC2A1 gene were genotyped in 375 cases and 199 controls from an initial discovery cohort (the Amsterdam-Rotterdam-Netherlands study). Replication testing was performed in The Rotterdam Study (the Netherlands) and study populations from Würzburg (Germany), the Age Related Eye Disease Study (AREDS; United States), Columbia University (United States), and Iowa University (United States). Subsequently, a meta-analysis of SNP association was performed. Results In the discovery cohort, significant genotypic association between three SNPs (rs3754219, rs4660687, and rs841853) and AMD was found. Replication in five large independent (Caucasian) cohorts (4,860 cases and 4,004 controls) did not yield consistent association results. The genotype frequencies for these SNPs were significantly different for the controls and/or cases among the six individual populations. Meta-analysis revealed significant heterogeneity of effect between the studies. Conclusions No overall association between SLC2A1 SNPs and AMD was demonstrated. Since the genotype frequencies for the three SLC2A1 SNPs were significantly different for the controls and/or cases between the six cohorts, this study corroborates previous evidence that population dependent genetic risk heterogeneity in AMD exists. PMID:22509097

Academic performance in adolescents born after ART-a nationwide registry-based cohort study.

Science.gov (United States)

Spangmose, A L; Malchau, S S; Schmidt, L; Vassard, D; Rasmussen, S; Loft, A; Forman, J; Pinborg, A

2017-02-01

Is academic performance in adolescents aged 15-16 years and conceived after ART, measured as test scores in ninth grade, comparable to that for spontaneously conceived (SC) adolescents? ART singletons had a significantly lower mean test score in the adjusted analysis when compared with SC singletons, yet the differences were small and probably not of clinical relevance. Previous studies have shown similar intelligence quotient (IQ) levels in ART and SC children, but only a few have been on adolescents. Academic performance measured with standardized national tests has not previously been explored in a complete national cohort of adolescents conceived after ART. A Danish national registry-based cohort including all 4766 ART adolescents (n = 2836 singletons and n = 1930 twins) born in 1995-1998 were compared with two SC control cohorts: a randomly selected singleton population (n = 5660) and all twins (n = 7064) born from 1995 to 1998 in Denmark. Nine children who died during the follow-up period were excluded from the study. Mean test scores on a 7-point-marking scale from -3 to 12 were compared, and adjustments were made for relevant reproductive and socio-demographic covariates including occupational and educational level of the parents. The crude mean test score was higher in both ART singletons and ART twins compared with SC adolescents. The crude mean differences were +0.41 (95% CI 0.30-0.53) and +0.45 (95% CI 0.28-0.62) between ART and SC singletons and between ART and SC twins, respectively. However, the adjusted mean overall test score was significantly lower for ART singletons compared with SC singletons (adjusted mean difference -0.15 (95% CI -0.29-(-0.02))). For comparison, the adjusted mean difference was +2.05 (95% CI 1.82-2.28) between the highest and the lowest parental educational level, suggesting that the effect of ART is weak compared with the conventional predictors. The adjusted analyses showed significantly lower mean test scores in mathematics

A web-based endodontic case difficulty assessment tool.

Science.gov (United States)

Shah, P K; Chong, B S

2018-01-25

To develop a web-based tool to facilitate identification, evaluation and management of teeth requiring endodontic treatment. Following a literature search and thorough analysis of existing case difficulty assessment forms, the web-based tool was developed using an online survey builder (Qualtrics, Qualtrics Lab, UT, USA). Following feedback from a pilot study, it was refined and improved. A study was performed, using the updated version (EndoApp) on a cohort (n = 53) of dental professionals and dental students. The participants were e-mailed instructions detailing the assessment of five test cases using EndoApp, followed by completion of a structured feedback form. Analysis of the EndoApp responses was used to evaluate usage times, whereas the results of the feedback forms were used to assess user experience and relevance, other potential applications and comments on further improvement/s. The average usage time was 2 min 7 s; the average times needed for the last three (Cases 3-5) were significantly less than the preceding two (Cases 1 & 2) test cases. An overwhelming majority of participants expressed favourable views on user experience and relevance of the web-based case difficulty assessment tool. Only two participants (4%) were unlikely or very unlikely to use EndoApp again. The potential application of EndoApp as an 'educational tool' and for 'primary care triage' was deemed the most popular features and of greater importance than the secondary options of 'fee setting' and as a 'dento-legal justification tool'. Within the study limitations, owing to its ability to quantify the level of difficulty and provide guidance, EndoApp was considered user-friendly and helped facilitate endodontic case difficulty assessment. From the feedback, further improvements and the development of a Smartphone App version are in progress. EndoApp may facilitate treatment planning, improve treatment cost-effectiveness and reduce frequency of procedural errors by providing

Academic performance in adolescents born after ART—a nationwide registry-based cohort study

DEFF Research Database (Denmark)

Spangmose, Anne Lærke; Malchau, Sara; Schmidt, Lone

2017-01-01

singletons and ART twins. LIMITATIONS, REASONS FOR CAUTION Missing data on educational test scores occurred in 6.6% of adolescents aged 15–16 years for the birth cohorts 1995–1997, where all of the children according to their age should have passed the ninth grade exam at the time of data retrieval......STUDY QUESTION Is academic performance in adolescents aged 15–16 years and conceived after ART, measured as test scores in ninth grade, comparable to that for spontaneously conceived (SC) adolescents? SUMMARY ANSWER ART singletons had a significantly lower mean test score in the adjusted analysis...... are based on national data, our findings can be applied to other populations. The findings of this paper suggest that a possible small negative effect of parental subfertility or ART treatment is counterbalanced by the higher educational level in the ART parents. STUDY FUNDING/COMPETING INTEREST...

Risk of anxiety and depressive disorders in patients with myocardial infarction: A nationwide population-based cohort study.

Science.gov (United States)

Feng, Hsin-Pei; Chien, Wu-Chien; Cheng, Wei-Tung; Chung, Chi-Hsiang; Cheng, Shu-Meng; Tzeng, Wen-Chii

2016-08-01

Anxiety and depressive symptoms are associated with adverse cardiovascular events after an acute myocardial infarction (MI). However, most studies focusing on anxiety or depression have used rating scales or self-report methods rather than clinical diagnosis. This study aimed to investigate the association between psychiatrist-diagnosed psychiatric disorders and cardiovascular prognosis.We sampled data from the National Health Insurance Research Database; 1396 patients with MI were recruited as the study cohort and 13,960 patients without MI were recruited as the comparison cohort. Cox proportional hazard regression models were used to examine the effect of MI on the risk of anxiety and depressive disorders.During the first 2 years of follow-up, patients with MI exhibited a significantly higher risk of anxiety disorders (adjusted hazard ratio [HR] = 5.06, 95% confidence interval [CI]: 4.61-5.54) and depressive disorders (adjusted HR = 7.23, 95% CI: 4.88-10.88) than those without MI did. Greater risk for anxiety and depressive disorders was observed among women and patients aged 45 to 64 years following an acute MI. Patients with post-MI anxiety had a 9.37-fold (95% CI: 4.45-19.70) higher risk of recurrent MI than those without MI did after adjustment for age, sex, socioeconomic status, and comorbidities.This nationwide population-based cohort study provides evidence that MI increases the risk of anxiety and depressive disorders during the first 2 years post-MI, and post-MI anxiety disorders are associated with a higher risk of recurrent MI.

Empiric guideline-recommended weight-based vancomycin dosing and mortality in methicillin-resistant Staphylococcus aureus bacteremia: a retrospective cohort study

Directory of Open Access Journals (Sweden)

Hall Ronald G

2012-04-01

Full Text Available Abstract Background No studies have evaluated the effect of guideline-recommended weight-based dosing on in-hospital mortality of patients with methicillin-resistant Staphylococcus aureus bacteremia. Methods This was a multicenter, retrospective, cohort study of patients with methicillin-resistant Staphylococcus aureus bacteremia receiving at least 48 hours of empiric vancomycin therapy between 01/07/2002 and 30/06/2008. We compared in-hospital mortality for patients treated empirically with weight-based, guideline-recommended vancomycin doses (at least 15 mg/kg/dose to those treated with less than 15 mg/kg/dose. We used a general linear mixed multivariable model analysis with variables identified a priori through a conceptual framework based on the literature. Results A total of 337 patients who were admitted to the three hospitals were included in the cohort. One-third of patients received vancomycin empirically at the guideline-recommended dose. Guideline-recommended dosing was not associated with in-hospital mortality in the univariable (16% vs. 13%, OR 1.26 [95%CI 0.67-2.39] or multivariable (OR 0.71, 95%CI 0.33-1.55 analysis. Independent predictors of in-hospital mortality were ICU admission, Pitt bacteremia score of 4 or greater, age 53 years or greater, and nephrotoxicity. Conclusions Empiric use of weight-based, guideline-recommended empiric vancomycin dosing was not associated with reduced mortality in this multicenter study.

Adverse childhood or adult experiences and risk of bilateral oophorectomy: a population-based case-control study.

Science.gov (United States)

Gazzuola Rocca, Liliana; Smith, Carin Y; Grossardt, Brandon R; Faubion, Stephanie S; Shuster, Lynne T; Stewart, Elizabeth A; Rocca, Walter A

2017-06-07

Bilateral oophorectomy has commonly been performed in conjunction with hysterectomy even in women without a clear ovarian indication; however, oophorectomy may have long-term deleterious consequences. To better understand this surgical practice from the woman's perspective, we studied the possible association of adverse childhood or adult experiences with the subsequent occurrence of bilateral oophorectomy. Population-based case-control study. Olmsted County, Minnesota (USA). From an established population-based cohort study, we sampled 128 women who underwent bilateral oophorectomy before age 46 years for a non-cancerous condition in 1988-2007 (cases) and 128 age-matched controls (±1 year). Information about adverse experiences was abstracted from the medical records dating back to age 15 years or earlier archived in the Rochester Epidemiology Project (REP) records-linkage system. Adverse childhood experiences were summarised using the Adverse Childhood Experience (ACE) score. We observed an association of bilateral oophorectomy performed before age 46 years with verbal or emotional abuse, physical abuse, any abuse, substance abuse in the household, and with an ACE score ≥1 experienced before age 19 years (OR=3.23; 95% CI 1.73 to 6.02; padult abuse are at increased risk of undergoing bilateral oophorectomy before menopause. We suggest that the association may be explained by a series of biological, emotional, and psychodynamic mechanisms. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Homocyst(e)ine and cardiovascular disease: a systematic review of the evidence with special emphasis on case-control studies and nested case-control studies.

Science.gov (United States)

Ford, Earl S; Smith, S Jay; Stroup, Donna F; Steinberg, Karen K; Mueller, Patricia W; Thacker, Stephen B

2002-02-01

Elevated concentrations of homocyst(e)ine are thought to increase the risk of vascular diseases including coronary heart disease and cerebrovascular disease. We searched MEDLINE (1966-1999), EMBASE (1974-1999), SciSearch (1974- 1999), and Dissertation Abstracts (1999) for articles and theses about homocyst(e)ine concentration and coronary heart disease and cerebrovascular disease. We included 57 publications (3 cohort studies, 12 nested case-control studies, 42 case-control studies) that reported results on 5518 people with coronary heart disease (11,068 control subjects) and 1817 people with cerebrovascular disease (4787 control subjects) in our analysis. For coronary heart disease, the summary odds ratios (OR) for a 5-micromol/l increase in homocyst(e)ine concentration were 1.06 (95% CI : 0.99-1.13) for 2 publications of cohort studies, 1.23 (95% CI : 1.07-1.41) for 10 publications of nested case-control studies, and 1.70 (95% CI : 1.50-1.93) for 26 publications of case-control studies. For cerebrovascular disease, the summary OR for a 5-micromol/l increase in homocyst(e)ine concentration were 1.10 (95% CI : 0.94-1.28) for 2 publications of cohort studies, 1.58 (95% CI : 1.35-1.85) for 5 publications of nested case-control studies, and 2.16 (95% CI : 1.65-2.82) for 17 publications of case-control studies. Prospective studies offer weaker support than case-control studies for an association between homocyst(e)ine concentration and cardiovascular disease. Although other lines of evidence support a role for homocyst(e)ine in the pathogenesis of cardiovascular disease, more information from prospective epidemiological studies or clinical trials is needed to clarify this role.

A Qualitative Inquiry into the formation of Generational Cohorts: a Case of an Emerging Market

Directory of Open Access Journals (Sweden)

Hiram Ting

2015-01-01

Full Text Available This study use sociological theories of generations to identify generational cohorts for market segmentation. These theories are predominantly used in the West, hence little is known about their relevance in emerging markets, such as Malaysia. Past studies have mostly borrowed cohort labels from that of the U.S. sources, and assumed that their characteristics can be construed in the Malaysian context. Given the exploratory nature of the study, a qualitative approach by means of personal interview was conducted to identify the actual cohorts in Sarawak, a state in Malaysia. Specifically, major societal and historical events that Sarawakians could overtly recall due to their attachment to them during formative years were elicited. Accordingly forty-eight interviews were recorded, transcribed and content-analysed. Five cohorts were identified, and they were different from that of the U.S. sources. They were subsequently labelled as Neoteric-inheritors, Prospective-pursuers, Social-strivers, Idealistic-strugglers and Battling-lifers based on their collective experience of the events. The results show the relevance of theories of generations for market segmentation in emerging market.

Cancer risk in patients with alopecia areata: a nationwide population-based matched cohort study.

Science.gov (United States)

Chen, Chih-Chiang; Chang, Yun-Ting; Liu, Han-Nan; Chen, Yi-Ju

2018-05-01

Alopecia areata (AA) is an organ-specific autoimmune disorder. Defective immune system related disorders are prone to increase the risk of cancer formation. However, the association among AA and variety of cancer types had never been studied. A nationwide population-based matched cohort study was conducted to evaluate the cancer risk in patients with AA. Records from Taiwan National Health Insurance Research Database were analyzed. Cases of AA from 1997 to 2013 and cancers registered in the catastrophic illness profile from the same time period were collected. The standard incidence ratio (SIR) of each cancer was calculated. In total, 2099 cancers among 162,499 patients with AA and without prior cancers were identified. The overall cancer risks in AA patients were slightly decreased, especially among male subjects (SIR: 0.89). Refer to individual cancer, the cancer risk of nonmelanoma skin cancer (NMSC) (SIR: 0.59), upper GI cancer (SIR: 0.70), liver cancer (SIR: 0.82), uterine, and cervix cancer (SIR: 0.84) were significantly lower in patients with AA. In contrast, AA patients were inclined to have lymphoma, breast cancer, kidney, and urinary bladder cancer with the SIR of 1.55, 2.93, and 2.95, respectively. Age stratified analyses revealed female AA patients younger than 50 years old have even higher risk of breast cancer (SIR: 3.37). Further sensitivity analysis showed similar results after excluding major autoimmune disorders. Cancer risk in AA patients is organ specific, and it is not associated with the underlying autoimmune disorders in patients with AA. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Replacement of traditional lectures with computer-based tutorials: a case study

Directory of Open Access Journals (Sweden)

Derek Lavelle

1996-12-01

Full Text Available This paper reports on a pilot project with a group of 60 second-year undergraduates studying the use of standard forms of contract in the construction industry. The project entailed the replacement of two of a series of nine scheduled lectures with a computer-based tutorial. The two main aims of the project were to test the viability of converting existing lecture material into computer-based material on an in-house production basis, and to obtain feedback from the student cohort on their behavioural response to the change in media. The effect on student performance was not measured at this stage of development.

Epidemiology of Pediatric Convulsive Status Epilepticus With Fever in the Emergency Department: A Cohort Study of 381 Consecutive Cases.

Science.gov (United States)

Hayakawa, Itaru; Miyama, Sahoko; Inoue, Nobuaki; Sakakibara, Hiroshi; Hataya, Hiroshi; Terakawa, Toshiro

2016-09-01

Pediatric convulsive status epilepticus with fever is common in the emergency setting but leads to severe neurological sequelae in some patients. To explore the epidemiology of convulsive status epilepticus with fever, a retrospective cohort covering all convulsive status epilepticus cases with fever seen in the emergency department of a tertiary care children's hospital were consecutively collected. Of the 381 consecutive cases gathered, 81.6% were due to prolonged febrile seizure, 6.6% to encephalopathy/encephalitis, 0.8% to meningitis, and 7.6% to epilepsy. In addition, seizures were significantly longer in encephalopathy/encephalitis cases than in prolonged febrile seizure cases (log rank test, P status epilepticus with fever in the emergency setting, and will help optimize the management of pediatric patients presenting to the emergency department with convulsive status epilepticus with fever. © The Author(s) 2016.

Cohort profile: the Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS), a multicentre cohort for socioeconomic inequalities in health monitoring.

Science.gov (United States)

Caranci, Nicola; Di Girolamo, Chiara; Giorgi Rossi, Paolo; Spadea, Teresa; Pacelli, Barbara; Broccoli, Serena; Ballotari, Paola; Costa, Giuseppe; Zengarini, Nicolás; Agabiti, Nera; Bargagli, Anna Maria; Cacciani, Laura; Canova, Cristina; Cestari, Laura; Biggeri, Annibale; Grisotto, Laura; Terni, Gianna; Costanzo, Gianfranco; Mirisola, Concetta; Petrelli, Alessio

2018-04-20

The Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS) is a system of integrated data on health outcomes, demographic and socioeconomic information, and represents a powerful tool to study health inequalities. IN-LiMeS is a multicentre and multipurpose pool of metropolitan population cohorts enrolled in nine Italian cities: Turin, Venice, Reggio Emilia, Modena, Bologna, Florence, Leghorn, Prato and Rome. Data come from record linkage of municipal population registries, the 2001 population census, mortality registers and hospital discharge archives. Depending on the source of enrolment, cohorts can be closed or open. The census-based closed cohort design includes subjects resident in any of the nine cities at the 2001 census day; 4 466 655 individuals were enrolled in 2001 in the nine closed cohorts. The open cohort design includes subjects resident in 2001 or subsequently registered by birth or immigration until the latest available follow-up (currently 31 December 2013). The open cohort design is available for Turin, Venice, Reggio Emilia, Modena, Bologna, Prato and Rome. Detailed socioeconomic data are available for subjects enrolled in the census-based cohorts; information on demographic characteristics, education and citizenship is available from population registries. The first IN-LiMeS application was the study of differentials in mortality between immigrants and Italians. Either using a closed cohort design (nine cities) or an open one (Turin and Reggio Emilia), individuals from high migration pressure countries generally showed a lower mortality risk. However, a certain heterogeneity between the nine cities was noted, especially among men, and an excess mortality risk was reported for some macroareas of origin and specific causes of death. We are currently working on the linkage of the 2011 population census data, the expansion of geographical coverage and the implementation of the open design in all the participating cohorts. © Article author

Second Malignant Neoplasms in Digestive Organs After Childhood Cancer: A Cohort-Nested Case-Control Study

International Nuclear Information System (INIS)

Tukenova, Markhaba; Diallo, Ibrahima; Anderson, Harald; Hawkins, Mike; Garwicz, Stanislaw; Sankila, Risto; El Fayech, Chiraz; Winter, Dave; Rubino, Carole; Adjadj, Elisabeth; Haddy, Nadia; Oberlin, Odile; Moller, Torgil; Langmark, Froydis

2012-01-01

Purpose: Cancers of the digestive system constitute a major risk for childhood cancer survivors treated with radiotherapy once they reach adulthood. The aim of this study was to determine therapy-related risk factors for the development of a second malignancy in the digestive organs (SMDO) after a childhood cancer. Methods and Materials: Among 4,568 2-year survivors of a childhood solid cancer diagnosed before 17 years of age at eight French and British centers, and among 25,120 patients diagnosed as having a malignant neoplasm before the age of 20 years, whose data were extracted from the Nordic Cancer Registries, we matched 58 case patients (41 men and 17 women) of SMDO and 167 controls, in their respective cohort, for sex, age at first cancer, calendar year of occurrence of the first cancer, and duration of follow-up. The radiation dose received at the site of each second malignancy and at the corresponding site of its matched control was estimated. Results: The risk of developing a SMDO was 9.7-fold higher in relation to the general populations in France and the United Kingdom. In the case-control study, a strong dose–response relationship was estimated, compared with that in survivors who had not received radiotherapy; the odds ratio was 5.2 (95% CI, 1.7–16.0) for local radiation doses between 10 and 29 Gy and 9.6 (95% CI, 2.6–35.2) for doses equal to or greater than 30 Gy. Chemotherapy was also found to increase the risk of developing SMDO. Conclusions: This study confirms that childhood cancer treatments strongly increase the risk of SMDO, which occur only after a very long latency period.

Fibromyalgia and Risk of Dementia-A Nationwide, Population-Based, Cohort Study.

Science.gov (United States)

Tzeng, Nian-Sheng; Chung, Chi-Hsiang; Liu, Feng-Cheng; Chiu, Yu-Hsiang; Chang, Hsin-An; Yeh, Chin-Bin; Huang, San-Yuan; Lu, Ru-Band; Yeh, Hui-Wen; Kao, Yu-Chen; Chiang, Wei-Shan; Tsao, Chang-Hui; Wu, Yung-Fu; Chou, Yu-Ching; Lin, Fu-Huang; Chien, Wu-Chien

2018-02-01

Fibromyalgia is a syndrome of chronic pain and other symptoms and is associated with patient discomfort and other diseases. This nationwide matched-cohort population-based study aimed to investigate the association between fibromyalgia and the risk of developing dementia, and to clarify the association between fibromyalgia and dementia. A total of 41,612 patients of age ≥50 years with newly diagnosed fibromyalgia between January 1, and December 31, 2000 were selected from the National Health Insurance Research Database of Taiwan, along with 124,836 controls matched for sex and age. After adjusting for any confounding factors, Fine and Gray competing risk analysis was used to compare the risk of developing dementia during the 10 years of follow-up. Of the study subjects, 1,704 from 41,612 fibromyalgia patients (21.23 per 1,000 person-years) developed dementia when compared to 4,419 from 124,836 controls (18.94 per 1,000 person-years). Fine and Gray competing risk analysis revealed that the study subjects were more likely to develop dementia (hazard ratio: 2.29, 95% CI: 2.16-2.42; P dementia in this study. The study subjects with fibromyalgia had a 2.77-fold risk of dementia in comparison to the control group. Therefore, further studies are needed to elucidate the underlying mechanisms of the association between fibromyalgia and the risk of dementia. Copyright © 2018 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

Cause of death in patients with poststroke epilepsy: Results from a nationwide cohort study.

Science.gov (United States)

Hansen, Julia; Åsberg, Signild; Kumlien, Eva; Zelano, Johan

2017-01-01

The risk of death is increased for persons with epilepsy. The literature on causes of death in epilepsy is based mainly on cohorts with epilepsy of mixed aetiologies. For clinical purposes and improved understanding of mortality in different epilepsies, more information is needed on mortality in epilepsies of specific causes. In poststroke epilepsy (PSE), seizures occur in a setting of vascular disease and high mortality rates. The extent to which epilepsy contributes to mortality in this patient group is poorly understood. We therefore aimed to describe causes of death (COD) in PSE on a national scale. A previously identified cohort of 7740 patients with epilepsy or seizures after a stroke in 2005-2010 was investigated. A total of 4167 deaths occurred before the end of 2014. The standardized mortality ratio for the study cohort was 3.56 (95% CI: 3.45-3.67). The main underlying causes of death were disorders of the circulatory system (60%) followed by neoplasms (12%). Diseases of the nervous system were the sixth leading underlying COD (3%), and epilepsy or status epilepticus was considered the underlying COD in approximately a similar proportion of cases as neurodegenerative disorders (0.9% and 1.1%, respectively). Epilepsy was considered a contributing COD in 14% of cases. Our findings highlight the importance of optimal management of vascular morbidity in patients with PSE. The large proportion of patients with epilepsy as a contributing COD indicate the need of high ambitions also regarding the management of seizures in patients with PSE.

Epidemiological study of venous thromboembolism in a big Danish cohort

DEFF Research Database (Denmark)

Severinsen, Marianne Tang; Kristensen, Søren Risom; Overvad, Kim

Introduction: Epidemiological data on venous thromboembolism (VT), i.e. pulmonary emboli (PE) and deep venous thrombosis (DVT) are sparse. We have examined VT-diagnoses registered in a big Danish Cohort study.  Methods: All first-time VT diagnoses in The Danish National Patient Register were...... were probable cases (1.7%) whereas for 449 (41.6%) the diagnosis could be excluded. The incidence rate was 1 per 1000 personyears. Out of the 632 cases 60% were DVT and 40% PE. 315 VT were considered idiopathic (49.8%), 311 were secondary (49.2%) and 15 were unclassifiable. 122 patients had cancer, 87...

Developmental dysplasia of the hip: impact of sonographic newborn hip screening on the outcome of early treated decentered hip joints-a single center retrospective comparative cohort study based on Graf's method of hip ultrasonography.

Science.gov (United States)

Tschauner, Christian; Fürntrath, Frank; Saba, Yasaman; Berghold, Andrea; Radl, Roman

2011-12-01

PURPOSE/BACKGROUND/INTRODUCTION: The aim of this study was to retrospectively evaluate the impact of neonatal sonographic hip screening using Graf's method for the management and outcome of orthopaedic treatment of decentered hip joints with developmental dysplasia of the hip (DDH), using three decades (1978-2007) of clinical information compiled in a medical database. Three representative cohorts of consecutive cases of decentered hip joints were selected according to different search criteria and inclusion and exclusion parameters: (1) cohort 1 (1978-1982; n = 80), without sonographic screening; (2) cohort 2.1 (1994-1996; n = 91), with nationwide established general sonographic screening according to the Graf-method; (3) cohort 2.2 (2003-2005; n = 91), with sonographic screening including referred cases for open reduction from non-screened populations. These three cohorts were compared for the following parameters: age at initial treatment, successful closed reduction, necessary overhead traction, necessary adductor-tenotomy, rate of open reduction, rate of avascular necrosis (AVN) and rate of secondary acetabuloplasty. The age at initial treatment was reduced from 5.5 months in the first cohort to 2 months in the two subsequent two cohorts and the rate of successful closed reduction increased from 88.7 to 98.9 and 95.6%, respectively. There was a statistically significant improvement in six out of seven parameters with sonographic hip screening; only the rate of secondary acetabuloplasty did not improve significantly. Compared to the era before the institution of a sonographic hip screening programme according to the Graf-method in Austria in 1992, ultrasound screening based-treatment of decentered hip joints has become safer, shorter and simpler: "safer" means lower rate of AVN, "shorter" means less treatment time due to earlier onset and "simpler" means that the devices are now less invasive and highly standardized.

Meat consumption and K-ras mutations in sporadic colon and rectal cancer in The Netherlands Cohort Study

NARCIS (Netherlands)

Brink, M.; Weijenberg, M.P.; Goeij, A.F.P.M. de; Roemen, G.M.J.M.; Lentjes, M.H.F.M.; Bruïne, A.P. de; Goldbohm, R.A.; Brandt, P.A. van den

2005-01-01

Case-cohort analyses were performed on meat and fish consumption in relation to K-ras mutations in 448 colon and 160 rectal cancers that occurred during 7.3 years of follow-up, excluding the first 2.3 years, and 2948 subcohort members of The Netherlands Cohort Study on diet and cancer. Adjusted

Occupational exposure to asbestos and risk of cholangiocarcinoma: a population-based case-control study in four Nordic countries.

Science.gov (United States)

Farioli, Andrea; Straif, Kurt; Brandi, Giovanni; Curti, Stefania; Kjaerheim, Kristina; Martinsen, Jan Ivar; Sparen, Pär; Tryggvadottir, Laufey; Weiderpass, Elisabete; Biasco, Guido; Violante, Francesco Saverio; Mattioli, Stefano; Pukkala, Eero

2018-03-01

To assess the association between occupational exposure to asbestos and the risk of cholangiocarcinoma (CC). We conducted a case-control study nested in the Nordic Occupational Cancer (NOCCA) cohort. We studied 1458 intrahepatic CC (ICC) and 3972 extrahepatic CC (ECC) cases occurring among subjects born in 1920 or later in Finland, Iceland, Norway and Sweden. Each case was individually matched by birth year, gender and country to five population controls. The cumulative exposure to asbestos (measured in fibres (f)/ml × years) was assessed by applying the NOCCA job-exposure matrix to data on occupations collected during national population censuses (conducted in 1960, 1970, 1980/81 and 1990). Odds ratios (OR) and 95% CI were estimated using conditional logistic regression models adjusted by printing industry work. We observed an increasing risk of ICC with cumulative exposure to asbestos: never exposed, OR 1.0 (reference category); 0.1-4.9 f/mL × years, OR 1.1 (95% CI 0.9 to 1.3); 5.0-9.9 f/mL × years, OR 1.3 (95% CI 0.9 to 2.1); 10.0-14.9 f/mL × years, OR 1.6 (95% CI 1.0 to 2.5); ≥15.0 f/mL × years, OR 1.7 (95% CI 1.1 to 2.6). We did not observe an association between cumulative asbestos exposure and ECC. Our study provides evidence that exposure to asbestos might be a risk factor for ICC. Our findings also suggest that the association between ECC and asbestos is null or weaker than that observed for ICC. Further studies based on large industrial cohorts of asbestos workers and possibly accounting for personal characteristics and clinical history are needed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Sardasht-Iran cohort study of chemical warfare victims: design and methods.

Science.gov (United States)

Ghazanfari, Tooba; Faghihzadeh, Soghrat; Aragizadeh, Hassan; Soroush, Mohammad-Reza; Yaraee, Roya; Mohammad Hassan, Zuhair; Foroutan, Abbas; Vaez-Mahdavi, Mohammad-Reza; Javadi, Mohammad-Ali; Moaiedmohseni, Sakine; Azizi, Fereidoun; Panahi, Yunes; Mostafaie, Ali; Ghasemi, Hassan; Shams, Jalaleddin; Pourfarzam, Shahryar; Jalali-Nadoushan, Mohammad-Reza; Fallahi, Faramarz; Ebtekar, Massoumeh; Davoudi, Seyyed-Masoud; Ghazanfari, Zeinab; Ardestani, Sussan K; Shariat-Panahi, Shamsa; Moin, Athar; Rezaei, Abbas; Kariminia, Amina; Ajdary, Soheila; Mahmoudi, Mahmoud; Roshan, Rasoul; Ghaderi, Sulayman; Babai, Mahmoud; Naghizadeh, Mohammad-Mehdi; Ghanei, Mohammad-Mostafa

2009-01-01

Insights into long-term clinical consequences of sulfur mustard have emerged from some investigations but less is known about the basic and molecular mechanisms of these complications. Sardasht-Iran Cohort Study is a comprehensive historical cohort study on Sardasht chemical victims' population which was designed to find out the long-term complications of sulfur mustard exposure and the basic mechanisms underlying clinical manifestations. This paper describes the design and methodology of Sardasht-Iran Cohort Study. In Sardasht-Iran Cohort Study, 500 individuals including 372 subjects from Sardasht, as the exposed group, and 128 subjects from Rabat, as the unexposed age-matched control group were evaluated. The exposed group was divided into two groups based on the severity of clinical complications at the time of exposure. Different samples including blood, sputum, saliva, tear, urine, and semen were collected for immunologic, hematologic, biochemical, and other laboratory analysis. Data were gathered from medical records, clinical examinations, laboratory tests, and questionnaires for psychological and lifestyle situations. The important distinctions setting this study apart from the previous ones are discussed. The Sardasht-Iran Cohort Study provides important information on various aspects of long-term consequences of sulfur mustard exposure. This database will provide a better position to suggest guidelines for the diagnosis, treatment, and prevention of delayed complications in the patients exposed to sulfur mustard.

Splenectomy and increased subsequent cancer risk: a nationwide population-based cohort study.

Science.gov (United States)

Sun, Li-Min; Chen, Hsuan-Ju; Jeng, Long-Bin; Li, Tsai-Chung; Wu, Shih-Chi; Kao, Chia-Hung

2015-08-01

Splenectomy has been suggested to have an impact on immunological function, and subsequent development of cancer has been recognized as a possible adverse effect of splenectomy. This study evaluated the possible association between splenectomy and malignancy in Taiwan. A cohort study consisted of including 2,603 patients with nontraumatic and 2,295 patients with traumatic splenectomy, and then randomly frequency matched with 4 participants without splenectomy. The Cox proportional hazard regression analysis was conducted to estimate the influence of splenectomy on cancer risk. Both nontraumatic and traumatic splenectomy had a significantly higher risk for overall cancer development (adjusted hazard ratios are 2.64 and 1.29 for nontraumatic and traumatic reasons, respectively). After adjusting for age, sex, and comorbidities, patients with splenectomy were associated with significantly higher risks for developing certain gastrointestinal tract cancers, other head and neck cancers, and hematological malignancies, and the phenomenon is more prominent in nontraumatic splenectomy group. This nationwide population-based study found that people with splenectomy have higher risks of developing overall cancer, as well as certain site-specific cancers, especially for patients with nontraumatic reasons. Copyright © 2015 Elsevier Inc. All rights reserved.

Increasing Incidence and Prevalence of World Health Organization Groups 1 to 4 Pulmonary Hypertension: A Population-Based Cohort Study in Ontario, Canada.

Science.gov (United States)

Wijeratne, D Thiwanka; Lajkosz, Katherine; Brogly, Susan B; Lougheed, M Diane; Jiang, Li; Housin, Ahmad; Barber, David; Johnson, Ana; Doliszny, Katharine M; Archer, Stephen L

2018-02-01

The World Health Organization recognizes 5 groups of pulmonary hypertension (PH), categorized by pathogenesis or comorbidity: 1-pulmonary arterial hypertension 2-left-heart disease, 3-lung disease and hypoxia 4-chronic thromboembolic disease, and 5-miscellaneous. The epidemiology of PH, apart from group 1, is largely unknown. We describe incidence, prevalence, comorbidities, mortality and prescribing patterns for groups 1 to 4 PH from 1993 to 2012. Case definitions are based on hospitalizations and emergency department visits, using the Institute for Clinical Evaluative Sciences data, which comprises linked databases of universal coverage health service records for Ontario residents. This cohort included 50 529 patients with PH. The annual incidence of adult PH increased from 2003 to 2012 from 24.1 to 28.7 cases/100 000 population and the annual prevalence from 1993 to 2012 from 99.8 to 127.3 cases/100 000 population, respectively. The most common form of adult PH was group 2, alone (34.2%) or combined with group 3 PH (29.3%). A diagnosis of PH increased the 1-year standardized mortality ratio 7.2-fold. Mortality in adults with PH was 13.0%, 36.4%, and 62.4%, at 30 days, 1 year, and 5 years, respectively. Mortality was highest in groups 2 and 3 and lowest in group 1. PH was present in only 3.6% of people with left heart disease, 0.7% with lung disease, and 1.4% with thromboembolic disease, suggesting that PH is a relatively rare complication of these common diseases. Children (age<16 years) accounted for 3.6% of the cohort. In children group 1 PH was most common (65.2%), and 5-year mortality was lower (21.4%) than in adults. Group 1-specific PH therapies were increasingly prescribed over time and paradoxically were often used in patients who seemed to have group 2, PH based on diagnostic codes indicating left heart disease. The incidence and prevalence of adult PH are increasing. Groups 2 and 3 are the most common and lethal forms of PH. This study identifies an

Polymorphisms in NFKB1 and TLR4 and Interaction with Dietary and Life Style Factors in Relation to Colorectal Cancer in a Danish Prospective Case-Cohort Study

DEFF Research Database (Denmark)

Kopp, Tine Iskov; Andersen, Vibeke; Tjoøneland, Anne

2015-01-01

Maintenance of a balance between commensal bacteria and the mucosal immune system is crucial and intestinal dysbiosis may be a key event in the pathogenesis of colorectal cancer (CRC). The toll-like receptor 4 (TLR4) is an important pattern-recognition receptor that regulates inflammation...... and barrier function in the gut by a mechanism that involves activation of the nuclear factor-kappa B (NF-kappa B) transcription factor. Dietary and life style factors may impact these functions. We therefore used a Danish prospective case-cohort study of 1010 CRC cases and 1829 randomly selected participants...... from the Danish Diet, Cancer and Health cohort to investigate three polymorphisms in NFKB1 and TLR4 and their possible interactions with diet and life style factors in relation to risk of CRC. Homozygous carriage of the variant allele of the TLR4/rs5030728 polymorphism was associated with increased...

Variations of care quality for infectious pulmonary tuberculosis in Taiwan: a population based cohort study

Directory of Open Access Journals (Sweden)

Chang Ray-E

2007-06-01

Full Text Available Abstract Background Effective and efficient care is required to prevent the spread of infectious pulmonary tuberculosis (PTB. We attempted to compare care quality among different healthcare institutions in Southern Taiwan. Methods This study conducted population-based retrospective cohort design. One tuberculosis sanatorium, 2 medical centers, 11 regional hospitals, and 15 district hospitals and primary practitioners in the study area had reported tuberculosis cases, registered from January 1 to June 30 2003. Those cases with sputum positive PTB were followed 15 months after anti-tuberculosis treatment initiation. Meanwhile, Level of conformance with diagnostic guidelines, efficiency of diagnostic and treatment process, and treatment were measured as main outcome. Association was investigated using Chi-square tests, Kruskal Wallis tests, Mann-Whiteney U tests, and multiple logistic regression analysis to evaluate outcome differences among different levels of institutions. Results The analyses included 421 patients. In comparison with patients receiving treatment at medical centers, regional hospitals, and district hospitals/primary practitioners, patients at the Chest Specialty Hospital were more likely to provide at least three sputum specimens (74.1% vs. 48.2%, 36.8%, and 50.0%, shorter workdays examining sputum smears (2.4 ± 2.4 days vs. 2.6 ± 2.1, 4.5 ± 3.1, and 3.5 ± 2.6 days, shorter interval between the first consultation and treatment (10.1 ± 18.3 days vs. 31.0 ± 53.6, 31.2 ± 70.4, and 25.4 ± 37.6 days, and a higher successful treatment rate (92.6% vs. 65.2%, 63.9%, and 68.0%. Furthermore, after adjusting age and gender, the patients treated by the pulmonologists and treated at Chest Specialty Hospital had significantly more successful treatment rate, of which odds ratios were 1.74 and 4.58 respectively. Conclusion Differences in care quality exist among different types of healthcare institutions and among individual physicians

A prospective cohort study to evaluate peridomestic infection as a determinant of dengue transmission: Protocol

Directory of Open Access Journals (Sweden)

Martínez-Vega Ruth

2012-04-01

Full Text Available Abstract Background Vector control programs, which have focused mainly on the patient house and peridomestic areas around dengue cases, have not produced the expected impact on transmission. This project will evaluate the assumption that the endemic/epidemic transmission of dengue begins around peridomestic vicinities of the primary cases. Its objective is to assess the relationship between symptomatic dengue case exposure and peridomestic infection incidence. Methods/Design A prospective cohort study will be conducted (in Tepalcingo and Axochiapan, in the state of Morelos, Mexico, using the state surveillance system for the detection of incident cases. Paired blood specimens will be collected from both the individuals who live with the incident cases and a sample of subjects residing within a 25-meter radius of such cases (exposed cohort, in order to measure dengue-specific antibodies. Other subjects will be selected from areas which have not presented any incident cases within 200 meters, during the two months preceding the sampling (non-exposed cohort. Symptomatic/asymptomatic incident infection will be considered as the dependent variable, exposure to confirmed dengue cases, as the principal variable, and the socio-demographic, environmental and socio-cultural conditions of the subjects, as additional explanatory variables. Discussion Results indicating a high infection rate among the exposed subjects would justify the application of peridomestic control measures and call for an evaluation of alternate causes for insufficient program impact. On the other hand, a low incidence of peridomestic-infected subjects would support the hypothesis that infection occurs outside the domicile, and would thus explain why the vector control measures applied in the past have exerted such a limited impact on cases incidence rates. The results of the present study may therefore serve to reassess site selection for interventions of this type.

Cohort Profile: the National Prostate Cancer Register of Sweden and Prostate Cancer data Base Sweden 2.0.

Science.gov (United States)

Van Hemelrijck, Mieke; Wigertz, Annette; Sandin, Fredrik; Garmo, Hans; Hellström, Karin; Fransson, Per; Widmark, Anders; Lambe, Mats; Adolfsson, Jan; Varenhorst, Eberhard; Johansson, Jan-Erik; Stattin, Pär

2013-08-01

In 1987, the first Regional Prostate Cancer Register was set up in the South-East health-care region of Sweden. Other health-care regions joined and since 1998 virtually all prostate cancer (PCa) cases are registered in the National Prostate Cancer Register (NPCR) of Sweden to provide data for quality assurance, bench marking and clinical research. NPCR includes data on tumour stage, Gleason score, serum level of prostate-specific antigen (PSA) and primary treatment. In 2008, the NPCR was linked to a number of other population-based registers by use of the personal identity number. This database named Prostate Cancer data Base Sweden (PCBaSe) has now been extended with more cases, longer follow-up and a selection of two control series of men free of PCa at the time of sampling, as well as information on brothers of men diagnosed with PCa, resulting in PCBaSe 2.0. This extension allows for studies with case-control, cohort or longitudinal case-only design on aetiological factors, pharmaceutical prescriptions and assessment of long-term outcomes. The NPCR covers >96% of all incident PCa cases registered by the Swedish Cancer Register, which has an underreporting of <3.7%. The NPCR is used to assess trends in incidence, treatment and outcome of men with PCa. Since the national registers linked to PCBaSe are complete, studies from PCBaSe 2.0 are truly population based.

No evidence of a causal relationship between hypothyroidism and glaucoma: A Danish nationwide register-based cohort study

Science.gov (United States)

2018-01-01

Background An interrelationship between hypothyroidism and glaucoma, due to a shared autoimmune background or based on deposition of mucopolysaccharides in the trabecular meshwork in the eye, has been suggested but is at present unsubstantiated. Therefore, our objective was to investigate, at a nationwide and population-based level, whether there is such an association. Subjects and methods Observational cohort study using record-linkage data from nationwide Danish health registers. 121,799 individuals diagnosed with a first episode of hypothyroidism were identified and were matched with 4 non-hypothyroid controls according to age and sex. Prevalence of glaucoma was recorded and cases and controls were followed over a mean of 7.1 years (range 0–17). Logistic and Cox regression models were used to assess the risk of glaucoma before and after the diagnosis of hypothyroidism, respectively. Results Overall, we found a higher prevalence of glaucoma in subjects with hypothyroidism as compared to controls (4.6% vs. 4.3%, p hypothyroidism, the odds ratio (OR) was significantly increased for glaucoma [1.09; 95% confidence interval (CI): 1.04–1.13]. Based on the Cox regression model, there was no increased risk of glaucoma after the diagnosis of hypothyroidism [hazard ratio (HR) 1.00; 95% CI: 0.96–1.06], and the HR decreased further after adjusting for pre-existing co-morbidity (0.88; 95% CI: 0.84–0.93). Conclusions There was an increased risk of glaucoma before but not after the diagnosis of hypothyroidism, suggesting that screening for glaucoma in hypothyroid individuals is unwarranted. PMID:29444121

A Case Study of Undergraduate Women in a Leadership Development Program at a Coeducational Institution

Science.gov (United States)

Haight, Lori P.

2010-01-01

The purpose of this interpretive case study was to explore the collegiate experiences of undergraduate women participating in a cohort women's-only leadership development program at a coeducational institution. Using a framework based on Kurt Lewin's psycho-social model of behavior being the function of a person interacting with the environment…

A retrospective case-cohort study comparing treatment outcomes in abacavir versus stavudine containing first line antiretroviral treatment regimens in children <3yrs old, at a paediatric programme based in Soweto, South Africa

Science.gov (United States)

Otwombe, Kennedy; Lazarus, Erica; Liberty, Afaaf; Gray, Glenda E.; Greeff, Oppel B. W.; Violari, Avy

2017-01-01

Introduction The current World Health Organization guideline for first line antiretroviral therapy (ART) in HIV-infected children recommends the use of abacavir and lamivudine as nucleoside backbones and no longer includes stavudine. We compared treatment outcomes with abacavir (ABC) versus stavudine (d4T) in a cohort of HIV-1 infected children 6 and 12 months after antiretroviral therapy was initiated. Methods This was a retrospective case-cohort study, using programmatic data from children enrolled in the Paediatric Wellness Programme at the Perinatal HIV Research Unit in Soweto, South Africa between 2005 and 2013. Children on abacavir/stavudine who had initiated ART at age 90% for ABC and d4T were similar too (95% in ABC vs. 86% in d4T, p = 0.10). The proportion of children who died over 12 months was 3.5% in the ABC and 7.9% in the d4T group (p = 0.27). Similarly, the anthropometric measures were comparable. Conclusions It is reassuring that in the short term, in this group of patients, the treatment outcomes were similar. PMID:28686654

Hospitalization for Pneumonia among Individuals With and Without HIV Infection, 1995-2007: A Danish Population-Based, Nationwide Cohort Study

DEFF Research Database (Denmark)

Sogaard, Ole S; Lohse, Nicolai; Gerstoft, Jan

2008-01-01

). Risk factors were assessed by Poisson regression. Results. @nbsp; The study included 3516 persons with HIV infection and 328,738 persons without HIV infection, which provided 23,677 person-years and 2,944,760 person-years of observation, respectively. Incidence rates of pneumonia in HIV......-infected individuals decreased from 50.6 hospitalizations per 1000 person-years (95% confidence interval [CI], 42.9-59.7 hospitalizations per 1000 person-years) during 1995-1996 to 19.7 hospitalizations per 1000 person-years (95% CI, 16.2-23.8 hospitalizations per 1000 person-years) during 2005-2007. Compared......-infected population. Methods. @nbsp; This was an observational cohort study conducted during 1995-2007. Each member of a Danish population-based nationwide cohort of HIV-infected individuals was matched with up to 99 control individuals from the general population. Data on age, mortality, emigration, and hospital...

Validating predictors of disease progression in a large cohort of primary-progressive multiple sclerosis based on a systematic literature review.

Directory of Open Access Journals (Sweden)

Jan-Patrick Stellmann

Full Text Available New agents with neuroprotective or neuroregenerative potential might be explored in primary-progressive Multiple Sclerosis (PPMS--the MS disease course with leading neurodegenerative pathology. Identification of patients with a high short-term risk for progression may minimize study duration and sample size. Cohort studies reported several variables as predictors of EDSS disability progression but findings were partially contradictory.To analyse the impact of published predictors on EDSS disease progression in a large cohort of PPMS patients.A systematic literature research was performed to identify predictors for disease progression in PPMS. Individual case data from the Sylvia Lawry Centre (SLC and the Hamburg MS patient database (HAPIMS was pooled for a retrospective validation of these predictors on the annualized EDSS change.The systematic literature analysis revealed heterogeneous data from 3 prospective and 5 retrospective natural history cohort studies. Age at onset, gender, type of first symptoms and early EDSS changes were available for validation. Our pooled cohort of 597 PPMS patients (54% female had a mean follow-up of 4.4 years and mean change of EDSS of 0.35 per year based on 2503 EDSS assessments. There was no significant association between the investigated variables and the EDSS-change.None of the analysed variables were predictive for the disease progression measured by the annualized EDSS change. Whether PPMS is still unpredictable or our results may be due to limitations of cohort assessments or selection of predictors cannot be answered. Large systematic prospective studies with new endpoints are needed.

Strabismus Incidence in a Danish Population-Based Cohort of Children

DEFF Research Database (Denmark)

Torp-Pedersen, Tobias; Boyd, Heather A; Skotte, Line

2017-01-01

, overall and by subtype, among children 7 years or younger. Design, Setting, and Participants: This population-based cohort study was conducted with data from 96 842 children enrolled in the Danish National Birth Cohort. Main Outcomes and Measures: Age-specific incidence and cumulative incidence and median...... identified in the cohort. We found an overall cumulative strabismus incidence of 2.56% (95% CI, 2.42-2.69) at 7 years. The overall incidence was similar among boys and girls. Two hundred sixteen participants (16.5%) (95% CI, 14.5-18.6) had congenital esotropia, 177 (13.5%) (95% CI, 11.7-15.5) had fully...... accommodative esotropia, 252 (19.3%) (95% CI, 17.1-21.5) had partially accommodative esotropia, and 181 (13.8%) (95% CI, 12.0-15.8) had exotropia. The esotropia:exotropia ratio was 5.4:1 (95% CI, 3.4:1 to 7.5:1). Age-specific incidence curves for congenital esotropia, fully accommodative esotropia, partially...

Developing effective web-based regional anesthesia education: a randomized study evaluating case-based versus non-case-based module design.

Science.gov (United States)

Kopp, Sandra L; Smith, Hugh M

2011-01-01

. Although residents believe that online learning should be used in anesthesia training, the results of this study do not demonstrate improved learning or justify the time and expense of developing complex case-based training modules. While there may be practical benefits of Web-based education, educators in regional anesthesia should be cautious about developing curricula based on learner preference data.

Nationwide population-based cohort study of celiac disease and risk of Ehlers-Danlos syndrome and joint hypermobility syndrome.

Science.gov (United States)

Laszkowska, Monika; Roy, Abhik; Lebwohl, Benjamin; Green, Peter H R; Sundelin, Heléne E K; Ludvigsson, Jonas F

2016-09-01

Patients with celiac disease (CD) often have articular complaints, and small prior studies suggest an association with Ehlers-Danlos syndrome (EDS)/joint hypermobility syndrome (JHS). This study examines the risks of EDS/JHS in patients with CD. This cohort study compared all individuals in Sweden diagnosed with CD based on small intestinal biopsy between 1969-2008 (n=28,631) to 139,832 matched reference individuals, and to a second reference group undergoing biopsy without having CD (n=16,104). Rates of EDS/JHS were determined based on diagnostic codes in the Swedish Patient Register. Hazard ratios (HRs) for EDS/JHS were estimated through Cox regression. There are 45 and 148 cases of EDS/JHS in patients with CD and reference individuals, respectively. This corresponds to a 49% increased risk of EDS/JHS in CD (95%CI=1.07-2.07). The HR for EDS was 2.43 (95%CI=1.20-4.91) and for JHS 1.34 (95%CI=0.93-1.95). Compared to reference individuals undergoing intestinal biopsy, CD was not a risk factor for EDS/JHS. A stronger association was seen in patients initially diagnosed with EDS/JHS and subsequently diagnosed with CD (odds ratio=2.29; 95%CI=1.21-4.34). Individuals with CD have higher risk of EDS/JHS than the general population, which may be due to surveillance bias or factors intrinsic to celiac development. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Costs and Efficiency of Online and Offline Recruitment Methods: A Web-Based Cohort Study.

Science.gov (United States)

Christensen, Tina; Riis, Anders H; Hatch, Elizabeth E; Wise, Lauren A; Nielsen, Marie G; Rothman, Kenneth J; Toft Sørensen, Henrik; Mikkelsen, Ellen M

2017-03-01

The Internet is widely used to conduct research studies on health issues. Many different methods are used to recruit participants for such studies, but little is known about how various recruitment methods compare in terms of efficiency and costs. The aim of our study was to compare online and offline recruitment methods for Internet-based studies in terms of efficiency (number of recruited participants) and costs per participant. We employed several online and offline recruitment methods to enroll 18- to 45-year-old women in an Internet-based Danish prospective cohort study on fertility. Offline methods included press releases, posters, and flyers. Online methods comprised advertisements placed on five different websites, including Facebook and Netdoktor.dk. We defined seven categories of mutually exclusive recruitment methods and used electronic tracking via unique Uniform Resource Locator (URL) and self-reported data to identify the recruitment method for each participant. For each method, we calculated the average cost per participant and efficiency, that is, the total number of recruited participants. We recruited 8252 study participants. Of these, 534 were excluded as they could not be assigned to a specific recruitment method. The final study population included 7724 participants, of whom 803 (10.4%) were recruited by offline methods, 3985 (51.6%) by online methods, 2382 (30.8%) by online methods not initiated by us, and 554 (7.2%) by other methods. Overall, the average cost per participant was €6.22 for online methods initiated by us versus €9.06 for offline methods. Costs per participant ranged from €2.74 to €105.53 for online methods and from €0 to €67.50 for offline methods. Lowest average costs per participant were for those recruited from Netdoktor.dk (€2.99) and from Facebook (€3.44). In our Internet-based cohort study, online recruitment methods were superior to offline methods in terms of efficiency (total number of participants

Association between bilirubin and risk of Non-Alcoholic Fatty Liver Disease based on a prospective cohort study.

Science.gov (United States)

Tian, Jianbo; Zhong, Rong; Liu, Cheng; Tang, Yuhan; Gong, Jing; Chang, Jiang; Lou, Jiao; Ke, Juntao; Li, Jiaoyuan; Zhang, Yi; Yang, Yang; Zhu, Ying; Gong, Yajie; Xu, Yanyan; Liu, Peiyi; Yu, Xiao; Xiao, Lin; Du, Min; Yang, Ling; Yuan, Jing; Wang, Youjie; Chen, Weihong; Wei, Sheng; Liang, Yuan; Zhang, Xiaomin; He, Meian; Wu, Tangchun; Yao, Ping; Miao, Xiaoping

2016-08-03

The study aimed to assess the association between total, direct, and indirect bilirubin and nonalcoholic fatty live disease (NAFLD) risk given its high prevalence and serious clinical prognosis. Among 27,009 subjects who participated in a healthy screening program from the Dongfeng-Tongji cohort study in 2008, 8189 eligible subjects (aged 35-86 years; males, 43.95%) were ultimately enrolled. The incidence rates of NAFLD in 2013 were compared with respect to baseline bilirubin levels among subjects free of NAFLD, and the effect sizes were estimated by logistic regression analysis. During 5 years follow-up, we observed 1956 cases of newly developed NAFLD with the overall incidence of 23.88%. Direct bilirubin was presented to inversely associate with NAFLD risk. Compared with quartile 1 of direct bilirubin, the multivariable-adjusted ORs (95% CIs) for NAFLD of quartile 2 to 4 were 1.104 (0.867-1.187), 0.843 (0.719-0.989), and 0.768 (0.652-0.905), respectively, P for trend 0.002). Similarly, inverse effects of direct bilirubin on NAFLD incidence were also observed when stratified by sex and BMI. However, no significant associations were found between total, and indirect bilirubin and NAFLD risk. Direct bilirubin reduced NAFLD risk independent of possible confounders among middle-aged and elderly Chinese population, probably based on the endogenous antioxidation of bilirubin.

Cancer risk among patients with multiple sclerosis: A cohort study in Isfahan, Iran.

Science.gov (United States)

Etemadifar, Masoud; Jahanbani-Ardakani, Hamidreza; Ghaffari, Sara; Fereidan-Esfahani, Maboobeh; Changaei, Hossein; Aghadoost, Nazila; Jahanbani Ardakani, Ameneh; Moradkhani, Negin

2017-01-01

Multiple sclerosis (MS), a central nervous system (CNS) autoimmune disorder, affects 2.3 million people around the world. Cancer kills around 7.5 million people annually. Both diseases have similar risks and intertwining molecular causes. Most studies focusing on MS and cancer have found an insignificant difference or reduction in the amount of cancer found in the MS community. We performed a cohort study using data from Isfahan Multiple Sclerosis Society (IMSS) and Isfahan cancer society and followed-up for 8 years on average (2006-2014). All of the 1718 MS patients were diagnosed according to McDonald's criteria, then standardized incidence ratio and the numbers of expected cancer case were calculated. While patients had an insignificant change in cancer prevalence, men had fewer cancer cases and women showed an increased prevalence of cancer. Certain types of cancer proved statistically significant. Breast cancer, nervous system cancers, and lymphoma were elevated in the cohort. Our results support the hypothesis that MS significantly affects certain cancers in a protective or associative manner. All cancer rates, except breast cancer, cancers located in the nervous system, and lymphomas were reduced in cohort, suggesting that unregulated immune function may provide protective effects to MS patients against cancer.

Performance of the colorectal cancer screening marker Sept9 is influenced by age, diabetes and arthritis: a nested case-control study

DEFF Research Database (Denmark)

Ørntoft, Mai-Britt Worm; Nielsen, Hans Jørgen; Ørntoft, Torben Falck

2015-01-01

Using a retrospective nested case–control study design, we studied plasma from 150 cancer and 150 controls selected from a well-characterized cohort of 4698 subjects referred for diagnostic colonoscopy due to CRC-related symptoms. The cases and controls were matched on age and gender, and moreover cases...... were stratified on tumor-site and tumor-stage. The selected cohort included a wide range of comorbidities. Plasma Sept9 levels were assessed using a commercially available PCR based assay (Epi-proColon). Results Clinical sensitivity for CRC stages I-IV was 37 %, 91 %, 77 %, and 89 %, and the overall...

Can the Use of Clickers or Continuous Assessment Motivate Critical Thinking? A Case Study Based on Corporate Finance Students

Science.gov (United States)

Morales, Lucía

2011-01-01

This study explores the use of clickers as a tool to support, encourage and motivate critical thinking in higher education students. A case study was carried out with a cohort of undergraduate students undertaking the BSc. in Accounting and Finance during the academic year 2009/10, where corporate finance was a major component. Since the students…

Risk of Dementia in Patients with Spinal Cord Injury: A Nationwide Population-Based Cohort Study.

Science.gov (United States)

Huang, Shih-Wei; Wang, Wei-Te; Chou, Lin-Chuan; Liou, Tsan-Hon; Lin, Hui-Wen

2017-02-01

Spinal cord injury (SCI) can cause physical disability and psychological distress; however, whether SCI is a risk factor for dementia is unclear. This study evaluated the incidence of dementia in patients with SCI. Study participants were recruited from a nationwide cohort during 2004-2007 and categorized into SCI (patients diagnosed with SCI; n = 941) and non-SCI (age- and sex-matched controls; n = 5060) cohorts. Each participant was followed for 7 years until diagnosis of dementia or December 31, 2010, whichever occurred first. Data were subjected to Kaplan-Meier and Cox regression analyses. The incidence of dementia was significantly higher in the SCI cohort (1106 per 100,000 person-years) than in the non-SCI cohort (p < 0.001). Patients with SCI had a significantly higher risk of dementia than did those without SCI (crude hazard ratio [HR] = 2.14, 95% confidence interval [CI], 1.57-2.92, p < 0.001 vs. adjusted HR = 1.95, 95% CI, 1.43-2.67, p < 0.001). Further analysis found that there is no statistical significance of higher risk for developing Alzheimer's disease among SCI patients, but that SCI patients were at higher risk of developing other types of dementia than the control cohort (crude HR = 1.88, 95% CI, 1.33-2.63, p < 0.001 vs. adjusted HR = 1.90, 95% CI, 1.35-2.68, p < 0.001). In conclusion, patients with SCI are at high risk of dementia, and effective dementia prevention strategies are recommended for comprehensive SCI care.

Mortality and Causes of Death in Patients With Osteogenesis Imperfecta: A Register-Based Nationwide Cohort Study

DEFF Research Database (Denmark)

Folkestad, Lars; Hald, Jannie Dahl; Canudas-Romo, Vladimir

2016-01-01

Osteogenesis imperfecta (OI) is a hereditary connective tissue disease that causes frequent fractures. Little is known about causes of death and length of survival in OI. The objective of this work was to calculate the risk and cause of death, and the median survival time in patients with OI...... five to one to the OI cohort. We calculated hazard ratios for all-cause mortality and subhazard ratios for cause-specific mortality in a comparison of the OI cohort and the reference population. We also calculated all-cause mortality hazard ratios for males, females, and age groups (0 to 17.99 years......, 18.00 to 34.99 years, 35.00 to 54.99 years, 55.00 to 74.99 years, and >75 years). We identified 687 cases of OI (379 women) and included 3435 reference persons (1895 women). A total of 112 patients with OI and 257 persons in the reference population died during the observation period. The all-cause...

The Autism Birth Cohort (ABC:a study of autism spectrum disorders in MoBa

Directory of Open Access Journals (Sweden)

Pål Surén

2014-12-01

Full Text Available Background: Autism spectrum disorders (ASDs are characterized by persistent deficits in social communication and interaction and restricted, repetitive patterns of behavior, interests or activities. In most cases, the cause of ASD is likely to be a combination of genetic predisposition and environmental exposures occurring in fetal life or early infancy. Consequently, a prospective pregnancy cohort like MoBa represents an ideal platform for studies of ASDs in children.Methods: The Autism Birth Cohort (ABC Study has identified potential ASD cases in MoBa through questionnaire- based screening, parental and professional referrals, and linkages to the Norwegian Patient Register. ASD diagnoses have been ascertained through in-person clinical assessments and medical record reviews.Current results: By the end of 2012, the ABC Study had identified 518 ASD cases in MoBa. The ASD prevalence in school-age children is 0.7-0.8%, which is in line with nationwide estimates for Norway. The most important source of ASD case identification was registry linkages, while only a minority was detected through early screening. Published findings show that screening at 18 months misses the majority of ASD cases. Analyses of risk factors for ASDs have shown that maternal use of folic acid supplements in early pregnancy may lower the child’s risk of developing ASDs and that paternal obesity appears to increase the child’s risk of ASDs.Future plans: ASD case identification will continue through annual registry linkages and subsequent reviews of medical records. Analyses of plasma samples and RNA samples will be conducted to investigate prenatal and perinatal microbial exposures, innate immune and inflammatory responses, biomarkers of autism risk, and exposures to xenobiotics. Analyses of deciduous teeth will also investigate the effect of medications and environmental toxins. Exome sequencing of DNA from ASD cases and their parents is ongoing, and will elucidate the

Open Access in Higher Education–Strategies for Engaging Diverse Student Cohorts

Directory of Open Access Journals (Sweden)

Luisa Signor

2014-07-01

Full Text Available With growth in online education, students gain tertiary qualifications through a mode more suited to their demographics such as work and life balance, learning styles and geographical accessibility. Inevitably this has led to a growth in diversity within student cohorts.The case study described in this paper illustrates strategies based on informed learning design for educating diverse student cohorts in an online program offered by Swinburne University of Technology. The case, an open-access, undergraduate information systems program, attracts mature age students studying while balancing employment and family commitments. The program’s open-access facet is the ‘no entry requirements’ such as prerequisite studies. Hence, many students enter the program via non-traditional pathways bringing significant differences in experience and consequent skill bases. The program’s innovative pedagogy encourages students to engage via active learning with tailored assessments, interactive communication via discussion boards and facilitated real-time sessions and formative feedback which include audio components.

Epilepsy in adults with mitochondrial disease: A cohort study.

Science.gov (United States)

Whittaker, Roger G; Devine, Helen E; Gorman, Grainne S; Schaefer, Andrew M; Horvath, Rita; Ng, Yi; Nesbitt, Victoria; Lax, Nichola Z; McFarland, Robert; Cunningham, Mark O; Taylor, Robert W; Turnbull, Douglass M

2015-12-01

The aim of this work was to determine the prevalence and progression of epilepsy in adult patients with mitochondrial disease. We prospectively recruited a cohort of 182 consecutive adult patients attending a specialized mitochondrial disease clinic in Newcastle upon Tyne between January 1, 2005 and January 1, 2008. We then followed this cohort over a 7-year period, recording primary outcome measures of occurrence of first seizure, status epilepticus, stroke-like episode, and death. Overall prevalence of epilepsy in the cohort was 23.1%. Mean age of epilepsy onset was 29.4 years. Prevalence varied widely between genotypes, with several genotypes having no cases of epilepsy, a prevalence of 34.9% in the most common genotype (m.3243A>G mutation), and 92.3% in the m.8344A>G mutation. Among the cohort as a whole, focal seizures, with or without progression to bilateral convulsive seizures, was the most common seizure type. Conversely, all of the patients with the m.8344A>G mutation and epilepsy experienced myoclonic seizures. Patients with the m.3243A>G mutation remain at high risk of developing stroke-like episodes (1.16% per year). However, although the standardized mortality ratio for the entire cohort was high (2.86), this ratio did not differ significantly between patients with epilepsy (2.96) and those without (2.83). Epilepsy is a common manifestation of mitochondrial disease. It develops early in the disease and, in the case of the m.3243A>G mutation, often presents in the context of a stroke-like episode or status epilepticus. However, epilepsy does not itself appear to contribute to the increased mortality in mitochondrial disease. © 2015 The Authors. Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.

Historic cohort study in Montreal's fur industry.

Science.gov (United States)

Guay, D; Siemiatycki, J

1987-01-01

A historic cohort mortality study was carried out among two groups of male workers in the Montreal fur industry: 263 dressers and dyers and 599 fur garment manufacturers. The first group is exposed to a very wide variety of chemicals used in tanning, cleaning, and dyeing fur, including substances considered to be carcinogenic and/or mutagenic. The second group is exposed to residue from the dressing and dyeing stage and to respirable fur dust. The cohorts consisted of all active members of two unions as of January 1, 1966. The mean age of the workers was 43.2 and the mean number of years since first employment 14.1. The follow-up period was from January 1, 1966, to December 31, 1981; 95% of the workers were successfully traced. Observed deaths were compared with those expected based on mortality rates of the population of metropolitan Montreal. Standardized mortality ratios (SMRs) for the manufacturers were significantly low, probably because of the ethnic composition of the cohort and a healthy worker effect. SMRs for the dressers and dyers were also low, but not as low as for the manufacturers. When attention was restricted to the French Canadians in the cohort, the observed deaths were close to the expected; there was a noteworthy excess of colorectal cancer (four observed, 0.8 expected) for dressers and dyers. Apart from this weak suggestive evidence, the results did not indicate any excess mortality risks in the fur industry. However, because of the relatively small number of expected and observed deaths in the cohort and especially among the heavily exposed dressers and dyers, the confidence intervals around SMR estimates were wide and excess risks cannot be ruled out.

Predictors of fibromyalgia: a population-based twin cohort study.

Science.gov (United States)

Markkula, Ritva A; Kalso, Eija A; Kaprio, Jaakko A

2016-01-15

Fibromyalgia (FM) is a pain syndrome, the mechanisms and predictors of which are still unclear. We have earlier validated a set of FM-symptom questions for detecting possible FM in an epidemiological survey and thereby identified a cluster with "possible FM". This study explores prospectively predictors for membership of that FM-symptom cluster. A population-based sample of 8343 subjects of the older Finnish Twin Cohort replied to health questionnaires in 1975, 1981, and 1990. Their answers to the set of FM-symptom questions in 1990 classified them in three latent classes (LC): LC1 with no or few symptoms, LC2 with some symptoms, and LC3 with many FM symptoms. We analysed putative predictors for these symptom classes using baseline (1975 and 1981) data on regional pain, headache, migraine, sleeping, body mass index (BMI), physical activity, smoking, and zygosity, adjusted for age, gender, and education. Those with a high likelihood of having fibromyalgia at baseline were excluded from the analysis. In the final multivariate regression model, regional pain, sleeping problems, and overweight were all predictors for membership in the class with many FM symptoms. The strongest non-genetic predictor was frequent headache (OR 8.6, CI 95% 3.8-19.2), followed by persistent back pain (OR 4.7, CI 95% 3.3-6.7) and persistent neck pain (OR 3.3, CI 95% 1.8-6.0). Regional pain, frequent headache, and persistent back or neck pain, sleeping problems, and overweight are predictors for having a cluster of symptoms consistent with fibromyalgia.

Durations of second stage of labor and pushing, and adverse neonatal outcomes: a population-based cohort study.

Science.gov (United States)

Sandström, A; Altman, M; Cnattingius, S; Johansson, S; Ahlberg, M; Stephansson, O

2017-03-01

The associations between duration of second stage of labor, pushing time and risk of adverse neonatal outcomes are not fully established. Therefore, we aimed to examine such relationships. A population-based cohort study including 42 539 nulliparous women with singleton infants born in cephalic presentation at ⩾37 gestational weeks, using the Stockholm-Gotland Obstetric Cohort, Sweden, and the Swedish Neonatal Quality Register, 2008 to 2013. Poisson regression was used to analyze estimated adjusted relative risks (RRs), with 95% confidence intervals (CIs). Outcome measures were umbilical artery acidosis (pH pushing pushing ⩾60 min increased rates of acidosis from 0.57 to 1.69% (adjusted RR 2.55 (95% CI 1.51 to 4.30)). Prolonged durations of second stage of labor and pushing are associated with increased RRs of adverse neonatal outcomes. Clinical assessment of fetal well-being is essential when durations of second stage and pushing increases.

Issues concerning the use of hormone replacement therapy and risk of fracture: a population-based, nested case-control study.

Science.gov (United States)

Corrao, Giovanni; Zambon, Antonella; Nicotra, Federica; Conti, Valentino; Nappi, Rossella E; Merlino, Luca

2008-01-01

To investigate the effect of duration, how recently it has been used, and age at start of hormone replacement therapy (HRT) and the risk of bone fracture. A population-based, nested case-control study was conducted in Lombardia, Northern Italy. The 78,294 women aged 45-75 years who received at least one HRT prescription during 1998-2000 were followed until 2005. Cases were women who experienced bone fracture during follow-up. Up to six controls were randomly selected for each case from the cohort after matching for age and date of cohort entry. The odds ratio of fracture associated with the use of HRT was estimated by conditional logistic regression. One thousand one hundred and seventy-four cases and 6760 controls were included. Compared with women who took HRT for less than 2 months, those who were treated for more than 20 months had an odds ratio (OR) of 0.80 (95% confidence interval 0.65, 0.99). This risk reduction was still significant among current HRT users (OR 0.71, 95% CI 0.55, 0.90) and in women who began therapy at the age of 55-65 years (OR 0.63, 95% CI 0.42, 0.94) or 65-75 years (OR 0.56, 95% CI 0.32, 0.99). There was no statistical evidence of a protective effect for women who had stopped treatment more than 6 months previously or those who began HRT at the age of 45-55 years. HRT should be continued for long periods to achieve an optimal protection from fracture. The fracture reducing potential of HRT seems to disappear after a few months without treatment and might mainly act in women who begin therapy at older age.

Remission, continuation, and incidence of eating disorders during early pregnancy: A validation study on a population-based birth cohort

Science.gov (United States)

Watson, Hunna J.; Von Holle, Ann; Hamer, Robert M.; Berg, Cecilie Knoph; Torgersen, Leila; Magnus, Per; Stoltenberg, Camilla; Sullivan, Patrick; Reichborn-Kjennerud, Ted; Bulik, Cynthia M.

2014-01-01

Background The objective of this study was to validate previously published rates of remission, continuation, and incidence of broadly defined eating disorders during pregnancy. The previous rate modeling was done by our group (Bulik et al. 2007) and yielded participants halfway into recruitment of the planned 100,000 pregnancies in the Norwegian Mother and Child (MoBa) Cohort at the Norwegian Institute of Public Health. This study aimed to internally validate the findings with the completed cohort. Methods 77267 pregnant women enrolled at 17 weeks gestation between 2001 and 2009 were included. Participants were split into a “training” sample (n=41243) based on participants in the MoBa version 2 dataset of the original study and a “validation” sample (n=36024) comprising individuals in the MoBa version 5 dataset that were not in the original study (Bulik et al. 2007). Internal validation of all original rate models involved fitting a calibration model to compare model parameters between the “training” and “validation” samples as well as bootstrap estimates of bias in the entire version 5 dataset. Results Remission, continuation, and incidence estimates from the “training” sample remained stable when evaluated via a split sample validation procedure. Pre-pregnancy prevalence estimates in the “validation” sample were 0.1% for anorexia nervosa, 1.0% for bulimia nervosa (BN), 3.3% for binge eating disorder (BED), and 0.1% for purging disorder (EDNOS-P). In early pregnancy, estimates were 0.2% for BN, 4.8% for BED, and eating disorders during pregnancy. Eating disorders during pregnancy were relatively common, occurring in nearly 1 in every 20 women, although almost all were cases of BED. Pregnancy was a window of remission from BN but a window of vulnerability for onset and continuation of BED. Training to detect the signs and symptoms of eating disorders by obstetricians/gynecologists and interventions to enhance pregnancy and neonatal outcomes

Study design of DIACORE (DIAbetes COhoRtE – a cohort study of patients with diabetes mellitus type 2

Directory of Open Access Journals (Sweden)

Dörhöfer Lena

2013-02-01

Full Text Available Abstract Background Diabetes mellitus type 2 (DM2 is highly associated with increased risk for chronic kidney disease (CKD, end stage renal disease (ESRD and cardiovascular morbidity. Epidemiological and genetic studies generate hypotheses for innovative strategies in DM2 management by unravelling novel mechanisms of diabetes complications, which is essential for future intervention trials. We have thus initiated the DIAbetes COhoRtE study (DIACORE. Methods DIACORE is a prospective cohort study aiming to recruit 6000 patients of self-reported Caucasian ethnicity with prevalent DM2 for at least 10 years of follow-up. Study visits are performed in University-based recruiting clinics in Germany using standard operating procedures. All prevalent DM2 patients in outpatient clinics surrounding the recruiting centers are invited to participate. At baseline and at each 2-year follow-up examination, patients are subjected to a core phenotyping protocol. This includes a standardized online questionnaire and physical examination to determine incident micro- and macrovascular DM2 complications, malignancy and hospitalization, with a primary focus on renal events. Confirmatory outcome information is requested from patient records. Blood samples are obtained for a centrally analyzed standard laboratory panel and for biobanking of aliquots of serum, plasma, urine, mRNA and DNA for future scientific use. A subset of the cohort is subjected to extended phenotyping, e.g. sleep apnea screening, skin autofluorescence measurement, non-mydriatic retinal photography and non-invasive determination of arterial stiffness. Discussion DIACORE will enable the prospective evaluation of factors involved in DM2 complication pathogenesis using high-throughput technologies in biosamples and genetic epidemiological studies.

Impact of Human Immunodeficiency Virus on the Burden and Severity of Influenza Illness in Malawian Adults: A Prospective Cohort and Parallel Case-Control Study.

Science.gov (United States)

Ho, Antonia; Aston, Stephen J; Jary, Hannah; Mitchell, Tamara; Alaerts, Maaike; Menyere, Mavis; Mallewa, Jane; Nyirenda, Mulinda; Everett, Dean; Heyderman, Robert S; French, Neil

2018-03-05

The impact of human immunodeficiency virus (HIV) infection on influenza incidence and severity in adults in sub-Saharan Africa is unclear. Seasonal influenza vaccination is recommended for HIV-infected persons in developed settings but is rarely implemented in Africa. We conducted a prospective cohort study to compare the incidence of laboratory-confirmed influenza illness between HIV-infected and HIV-uninfected adults in Blantyre, Malawi. In a parallel case-control study, we explored risk factors for severe influenza presentation of severe (hospitalized) lower respiratory tract infection, and mild influenza (influenza-like illness [ILI]). The cohort study enrolled 608 adults, of whom 360 (59%) were HIV infected. Between April 2013 and March 2015, 24 of 229 ILI episodes (10.5%) in HIV-infected and 5 of 119 (4.2%) in HIV-uninfected adults were positive for influenza by means of polymerase chain reaction (incidence rate, 46.0 vs 14.5 per 1000 person-years; incidence rate ratio, 2.75; 95% confidence interval, 1.02-7.44; P = .03; adjusted for age, sex, household crowding, and food security). In the case-control study, influenza was identified in 56 of 518 patients (10.8%) with hospitalized lower respiratory tract infection, and 88 or 642 (13.7%) with ILI. The HIV prevalence was 69.6% and 29.6%, respectively, among influenza-positive case patients and controls. HIV was a significant risk factor for severe influenza (odds ratio, 4.98; 95% confidence interval, 2.09-11.88; P factor for influenza-associated ILI and severe presentation in this high-HIV prevalence African setting. Targeted influenza vaccination of HIV-infected African adults should be reevaluated, and the optimal mechanism for vaccine introduction in overstretched health systems needs to be determined. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Risk of lung cancer in patients with gastro-esophageal reflux disease: a population-based cohort study

Directory of Open Access Journals (Sweden)

Chi-Kuei Hsu

2016-12-01

Full Text Available This large-scale, controlled cohort study estimated the risks of lung cancer in patients with gastro-esophageal reflux disease (GERD in Taiwan. We conducted this population-based study using data from the National Health Insurance Research Database of Taiwan during the period from 1997 to 2010. Patients with GERD were diagnosed using endoscopy, and controls were matched to patients with GERD at a ratio of 1:4. We identified 15,412 patients with GERD and 60,957 controls. Compared with the controls, the patients with GERD had higher rates of osteoporosis, diabetes mellitus, asthma, chronic obstructive pulmonary disease, pneumonia, bronchiectasis, depression, anxiety, hypertension, dyslipidemia, chronic liver disease, congestive heart failure, atrial fibrillation, stroke, chronic kidney disease, and coronary artery disease (all P < .05. A total of 85 patients had lung cancer among patients with GERD during the follow-up of 42,555 person-years, and the rate of lung cancer was 0.0020 per person-year. By contrast, 232 patients had lung cancer among patients without GERD during the follow-up of 175,319 person-years, and the rate of lung cancer was 0.0013 per person-year. By using stepwise Cox regression model, the overall incidence of lung cancer remained significantly higher in the patients with GERD than in the controls (hazard ratio, 1.53; 95% CI [1.19–1.98]. The cumulative incidence of lung cancer was higher in the patients with GERD than in the controls (P = .0012. In conclusion, our large population-based cohort study provides evidence that GERD may increase the risk of lung cancer in Asians.

Anabolic steroids and cardiovascular risk: A national population-based cohort study.

Science.gov (United States)

Thiblin, Ingemar; Garmo, Hans; Garle, Mats; Holmberg, Lars; Byberg, Liisa; Michaëlsson, Karl; Gedeborg, Rolf

2015-07-01

Non-therapeutic use of anabolic androgenic steroids (AAS) has been associated with various adverse effects; one of the most serious being direct cardiovascular effects with unknown long-term consequences. Therefore, large studies of the association between AAS and cardiovascular outcomes are warranted. We investigated cardiovascular morbidity and mortality in individuals who tested positive for AAS. Between 2002 and 2009, a total of 2013 men were enrolled in a cohort on the date of their first AAS test. Mortality and morbidity after cohort entry was retrieved from national registries. Of the 2013 individuals, 409 (20%) tested positive for AAS. These men had twice the cardiovascular morbidity and mortality rate as those with negative tests (adjusted hazard ratio (aHR) 2.0; 95% confidence interval (CI) 1.2-3.3). Compared to the Swedish population, all tested men had an increased risk of premature death from all causes (standardized mortality ratio for AAS-positive: 19.3, 95% CI 12.4-30.0; for AAS-negative: 8.3, 95% CI 6.1-11.0). Non-therapeutic exposure to AAS appears to be an independent risk factor for cardiovascular morbidity and premature death. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Acute cardiovascular events and all-cause mortality in patients with hyperthyroidism: a population-based cohort study.

Science.gov (United States)

Dekkers, Olaf M; Horváth-Puhó, Erzsébet; Cannegieter, Suzanne C; Vandenbroucke, Jan P; Sørensen, Henrik Toft; Jørgensen, Jens Otto L

2017-01-01

Several studies have shown an increased risk for cardiovascular disease (CVD) in hyperthyroidism, but most studies have been too small to address the effect of hyperthyroidism on individual cardiovascular endpoints. Our main aim was to assess the association among hyperthyroidism, acute cardiovascular events and mortality. It is a nationwide population-based cohort study. Data were obtained from the Danish Civil Registration System and the Danish National Patient Registry, which covers all Danish hospitals. We compared the rate of all-cause mortality as well as venous thromboembolism (VTE), acute myocardial infarction (AMI), ischemic and non-ischemic stroke, arterial embolism, atrial fibrillation (AF) and percutaneous coronary intervention (PCI) in the two cohorts. Hazard ratios (HR) with 95% confidence intervals (95% CI) were estimated. The study included 85 856 hyperthyroid patients and 847 057 matched population-based controls. Mean follow-up time was 9.2 years. The HR for mortality was highest in the first 3 months after diagnosis of hyperthyroidism: 4.62, 95% CI: 4.40-4.85, and remained elevated during long-term follow-up (>3 years) (HR: 1.35, 95% CI: 1.33-1.37). The risk for all examined cardiovascular events was increased, with the highest risk in the first 3 months after hyperthyroidism diagnosis. The 3-month post-diagnosis risk was highest for atrial fibrillation (HR: 7.32, 95% CI: 6.58-8.14) and arterial embolism (HR: 6.08, 95% CI: 4.30-8.61), but the risks of VTE, AMI, ischemic and non-ischemic stroke and PCI were increased also 2- to 3-fold. We found an increased risk for all-cause mortality and acute cardiovascular events in patients with hyperthyroidism. © 2017 European Society of Endocrinology.

The high burden of infant deaths in rural Burkina Faso: a prospective community-based cohort study

Directory of Open Access Journals (Sweden)

Diallo Abdoulaye

2012-09-01

Full Text Available Abstract Background Infant mortality rates (IMR remain high in many sub-Saharan African countries, especially in rural settings where access to health services may be limited. Studies in such communities can provide relevant data on the burden of and risk factors for infant death. We measured IMR and explored risk factors for infant death in a cohort of children born in Banfora Health District, a rural area in South-West Burkina Faso. Methods A prospective community-based cohort study was nested within the PROMISE-EBF trial (NCT00397150 in 24 villages of the study area. Maternal and infant baseline characteristics were collected at recruitment and after birth, respectively. Home visits were conducted at weeks 3, 6, 12, 24 and 52 after birth. Descriptive statistics were calculated using robust standard errors to account for cluster sampling. Cox multivariable regression was used to investigate potential risk factors for infant death. Results Among the 866 live born children included in the study there were 98 infant deaths, yielding an IMR of 113 per 1000 live births (95% CI: 89–143. Over 75% of infant deaths had occurred by 6 months of age and the post neonatal infant mortality rate was 67 per 1000 live births (95% CI: 51–88. Infections (35% and preterm births complications (23% were the most common probable causes of death by 6 months. Multivariable analyses identified maternal history of child death, polygyny, twin births and poor anthropometric z-scores at week-3 as factors associated with increased risk of infant death. Conclusions We observed a very high IMR in a rural area of Burkina Faso, a country where 75% of the population lives in rural settings. Community-based health interventions targeting mothers and children at high risk are urgently needed to reduce the high burden of infant deaths in these areas.

The high burden of infant deaths in rural Burkina Faso: a prospective community-based cohort study.

Science.gov (United States)

Hama Diallo, Abdoulaye; Meda, Nicolas; Sommerfelt, Halvor; Traore, Germain S; Cousens, Simon; Tylleskar, Thorkild

2012-09-05

Infant mortality rates (IMR) remain high in many sub-Saharan African countries, especially in rural settings where access to health services may be limited. Studies in such communities can provide relevant data on the burden of and risk factors for infant death. We measured IMR and explored risk factors for infant death in a cohort of children born in Banfora Health District, a rural area in South-West Burkina Faso. A prospective community-based cohort study was nested within the PROMISE-EBF trial (NCT00397150) in 24 villages of the study area. Maternal and infant baseline characteristics were collected at recruitment and after birth, respectively. Home visits were conducted at weeks 3, 6, 12, 24 and 52 after birth. Descriptive statistics were calculated using robust standard errors to account for cluster sampling. Cox multivariable regression was used to investigate potential risk factors for infant death. Among the 866 live born children included in the study there were 98 infant deaths, yielding an IMR of 113 per 1000 live births (95% CI: 89-143). Over 75% of infant deaths had occurred by 6 months of age and the post neonatal infant mortality rate was 67 per 1000 live births (95% CI: 51-88). Infections (35%) and preterm births complications (23%) were the most common probable causes of death by 6 months. Multivariable analyses identified maternal history of child death, polygyny, twin births and poor anthropometric z-scores at week-3 as factors associated with increased risk of infant death. We observed a very high IMR in a rural area of Burkina Faso, a country where 75% of the population lives in rural settings. Community-based health interventions targeting mothers and children at high risk are urgently needed to reduce the high burden of infant deaths in these areas.

Cigarette smoking and the risk of adult leukemia: results from the Three Mile Island cohort study.

Science.gov (United States)

Xu, Xiaohui; Talbott, Evelyn O; Zborowski, Jeanne V; Rager, Judith R

2007-01-01

Smoking is an unconfirmed risk factor for the development of leukemia. The authors examined the potential link using data from the Three Mile Island cohort for the period 1979-1995. Eligible for analysis were 24,539 individuals aged 14 years or older who were followed up over 16 years from the Three Mile Island cohort. The authors identified all incident leukemia cases through the Pennsylvania Department of Health Cancer Registry. They used the Cox proportional hazards model to evaluate the relationships and observed 42 incident leukemia cases, including 15 acute myeloid leukemia (AML) cases, in the cohort. After controlling for other confounding factors, the authors found current smoking to be associated with an increased risk of adult AML (relative risk = 3.47; 95% confidence interval = 1.002-11.99). The authors also observed a marginally significant linear trend of risk of AML associated with the number of years smoked (p = .06). The results from this study suggested that cigarette smoking was associated with an increased risk of adult AML. Further investigation is required to confirm these findings.

Association of Research Self-Efficacy with Medical Student Career Interests, Specialization, and Scholarship: A Case Study

Science.gov (United States)

Bierer, S. Beth; Prayson, Richard A.; Dannefer, Elaine F.

2015-01-01

This study used variables proposed in social cognitive career theory (SCCT) to focus the evaluation of a research curriculum at the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University (CCLCM). Eight cohorts of CCLCM medical students completed a web-based version of the six-scale Clinical Research Appraisal…

Cardiovascular outcomes associated with canagliflozin versus other non-gliflozin antidiabetic drugs: population based cohort study.

Science.gov (United States)

Patorno, Elisabetta; Goldfine, Allison B; Schneeweiss, Sebastian; Everett, Brendan M; Glynn, Robert J; Liu, Jun; Kim, Seoyoung C

2018-02-06

To evaluate the cardiovascular safety of canagliflozin, a sodium-glucose cotransporter 2 inhibitor for the treatment of type 2 diabetes mellitus, in direct comparisons with DPP-4 inhibitors (DPP-4i), GLP-1 receptor agonists (GLP-1RA), or sulfonylureas, as used in routine practice. Population based retrospective cohort study. Nationwide sample of patients with type 2 diabetes from a large de-identified US commercial healthcare database (Optum Clinformatics Datamart). Three pairwise 1:1 propensity score matched cohorts of patients with type 2 diabetes 18 years and older who initiated canagliflozin or a comparator non-gliflozin antidiabetic agent (ie, a DPP-4i, a GLP-1RA, or a sulfonylurea) between April 2013 and September 2015. The primary outcomes were heart failure admission to hospital and a composite cardiovascular endpoint (comprised of being admitted to hospital for acute myocardial infarction, ischemic stroke, or hemorrhagic stroke). Hazard ratios and 95% confidence intervals were estimated in each propensity score matched cohort controlling for more than 100 baseline characteristics. During a 30 month period, the hazard ratio for heart failure admission to hospital associated with canagliflozin was 0.70 (95% confidence interval 0.54 to 0.92) versus a DPP-4i (n=17 667 pairs), 0.61 (0.47 to 0.78) versus a GLP-1RA (20 539), and 0.51 (0.38 to 0.67) versus a sulfonylurea (17 354 ). The hazard ratio for the composite cardiovascular endpoint associated with canagliflozin was 0.89 (0.68 to 1.17) versus a DPP-4i, 1.03 (0.79 to 1.35) versus a GLP-1RA, and 0.86 (0.65 to 1.13) versus a sulfonylurea. Results were similar in sensitivity analyses further adjusting for baseline hemoglobin A1c levels and in subgroups of patients with and without prior cardiovascular disease or heart failure. In this large cohort study, canagliflozin was associated with a lower risk of heart failure admission to hospital and with a similar risk of myocardial infarction or stroke in

Longitudinal Assessment of Self-Reported Recent Back Pain and Combat Deployment in the Millennium Cohort Study

Science.gov (United States)

2016-11-15

deployment and self-reported recent back pain in a population- based U.S. military cohort. Summary of Background Data. The study consisted of Millennium Cohort...acute injury based on a ‘‘diathesis-stress’’ model in which predis- posing psychological characteristics are activated by stress.40 In our study , both...Other studies have shown psychosocial and psycho- logical factors, including depression, psychological distress, passive coping strategies, fear

Cohort profile: LIFEWORK, a prospective cohort study on occupational and environmental risk factors and health in the Netherlands.

Science.gov (United States)

Reedijk, Marije; Lenters, Virissa; Slottje, Pauline; Pijpe, Anouk; Peeters, Petra H; Korevaar, Joke C; Bueno-de-Mesquita, Bas; Verschuren, W M Monique; Verheij, Robert A; Pieterson, Inka; van Leeuwen, Flora E; Rookus, Matti A; Kromhout, Hans; Vermeulen, Roel C H

2018-02-03

LIFEWORK is a large federated prospective cohort established in the Netherlands to quantify the health effects of occupational and environmental exposures. This cohort is also the Dutch contribution to the international Cohort Study of Mobile Phone Use and Health (COSMOS). In this paper, we describe the study design, ongoing data collection, baseline characteristics of participants and the repeatability of key questionnaire items. 88 466 participants were enrolled in three cohort studies in 2011-2012. Exposure information was collected by a harmonised core questionnaire, or modelled based on occupational and residential histories; domains include air pollution (eg, nitrogen dioxide (NO 2 ), particulate matter with diameter ≤2.5 µm (PM 2.5 )), noise, electromagnetic fields (EMF), mobile phone use, shift work and occupational chemical exposures. Chronic and subacute health outcomes are assessed by self-report and through linkage with health registries. Participants had a median age of 51 years at baseline (range 19-87), and the majority are female (90%), with nurses being over-represented. Median exposure levels of NO 2 , PM 2.5 , EMF from base stations and noise at the participants' home addresses at baseline were 22.9 µg/m 3 , 16.6 µg/m 3 , 0.003 mWm 2 and 53.1 dB, respectively. Twenty-two per cent of participants reported to have started using a mobile phone more than 10 years prior to baseline. Repeatability for self-reported exposures was moderate to high (weighted kappa range: 0.69-1) for a subset of participants (n=237) who completed the questionnaire twice. We are actively and passively observing participants; we plan to administer a follow-up questionnaire every 4-5 years-the first follow-up will be completed in 2018-and linkage to cause-of-death and cancer registries occurs on a (bi)annual basis. This prospective cohort offers a unique, large and rich resource for research on contemporary occupational and environmental health risks and will

Estimates and Predictions of Coal Workers' Pneumoconiosis Cases among Redeployed Coal Workers of the Fuxin Mining Industry Group in China: A Historical Cohort Study.

Directory of Open Access Journals (Sweden)

Bing Han

Full Text Available This research was aimed at estimating possible Coal workers' pneumoconiosis (CWP cases as of 2012, and predicting future CWP cases among redeployed coal workers from the Fuxin Mining Industry Group. This study provided the scientific basis for regulations on CWP screening and diagnosis and labor insurance policies for redeployed coal workers of resource-exhausted mines. The study cohort included 19,116 coal workers. The cumulative incidence of CWP was calculated by the life-table method. Possible CWP cases by occupational category were estimated through the average annual incidence rate of CWP and males' life expectancy. It was estimated that 141 redeployed coal workers might have suffered from CWP as of 2012, and 221 redeployed coal workers could suffer from CWP in the future. It is crucial to establish a set of feasible and affordable regulations on CWP screening and diagnosis as well as labor insurance policies for redeployed coal workers of resource-exhausted coal mines in China.

Estimates and Predictions of Coal Workers’ Pneumoconiosis Cases among Redeployed Coal Workers of the Fuxin Mining Industry Group in China: A Historical Cohort Study

Science.gov (United States)

Han, Bing; Liu, Hongbo; Zhai, Guojiang; Wang, Qun; Liang, Jie; Zhang, Mengcang; Cui, Kai; Shen, Fuhai; Yi, Hongbo; Li, Yuting; Zhai, Yuhan; Sheng, Yang; Chen, Jie

2016-01-01

This research was aimed at estimating possible Coal workers’ pneumoconiosis (CWP) cases as of 2012, and predicting future CWP cases among redeployed coal workers from the Fuxin Mining Industry Group. This study provided the scientific basis for regulations on CWP screening and diagnosis and labor insurance policies for redeployed coal workers of resource-exhausted mines. The study cohort included 19,116 coal workers. The cumulative incidence of CWP was calculated by the life-table method. Possible CWP cases by occupational category were estimated through the average annual incidence rate of CWP and males’ life expectancy. It was estimated that 141 redeployed coal workers might have suffered from CWP as of 2012, and 221 redeployed coal workers could suffer from CWP in the future. It is crucial to establish a set of feasible and affordable regulations on CWP screening and diagnosis as well as labor insurance policies for redeployed coal workers of resource-exhausted coal mines in China. PMID:26845337

Estimates and Predictions of Coal Workers' Pneumoconiosis Cases among Redeployed Coal Workers of the Fuxin Mining Industry Group in China: A Historical Cohort Study.

Science.gov (United States)

Han, Bing; Liu, Hongbo; Zhai, Guojiang; Wang, Qun; Liang, Jie; Zhang, Mengcang; Cui, Kai; Shen, Fuhai; Yi, Hongbo; Li, Yuting; Zhai, Yuhan; Sheng, Yang; Chen, Jie

2016-01-01

This research was aimed at estimating possible Coal workers' pneumoconiosis (CWP) cases as of 2012, and predicting future CWP cases among redeployed coal workers from the Fuxin Mining Industry Group. This study provided the scientific basis for regulations on CWP screening and diagnosis and labor insurance policies for redeployed coal workers of resource-exhausted mines. The study cohort included 19,116 coal workers. The cumulative incidence of CWP was calculated by the life-table method. Possible CWP cases by occupational category were estimated through the average annual incidence rate of CWP and males' life expectancy. It was estimated that 141 redeployed coal workers might have suffered from CWP as of 2012, and 221 redeployed coal workers could suffer from CWP in the future. It is crucial to establish a set of feasible and affordable regulations on CWP screening and diagnosis as well as labor insurance policies for redeployed coal workers of resource-exhausted coal mines in China.

Salt intake, cured meat consumption, refrigerator use and stomach cancer incidence: A prospective cohort study (Netherlands)

NARCIS (Netherlands)

Brandt, P.A. van den; Botterweck, A.A.M.; Goldbohm, R.A.

2003-01-01

Objective: Many case-control studies have reported that salt and cured meat intake are positively, and refrigerator use is inversely, associated with stomach cancer risk. In the current prospective study these associations were evaluated. Methods: The Netherlands Cohort Study consisted of 120,852

Association Between Prepartum Maternal Iron Deficiency and Offspring Risk of Schizophrenia: Population-Based Cohort Study With Linkage of Danish National Registers

DEFF Research Database (Denmark)

Sørensen, Holger J; Nielsen, Philip R; Pedersen, Carsten B

2010-01-01

Recent findings suggest that maternal iron deficiency may increase the risk of schizophrenia-spectrum disorder in offspring. We initiated this study to determine whether maternal prepartum anemia influences offspring risk of schizophrenia. We conducted a population-based study with individual...... a 1.60-fold (95% confidence interval = 1.16-2.15) increased risk of schizophrenia. Although the underlying mechanisms are unknown and independent replication is needed, our findings suggest that maternal iron deficiency increases offspring risk of schizophrenia....... record linkage of the Danish Civil Registration System, the Danish Psychiatric Central Register, and the Danish National Hospital Register. In a cohort of 1 115 752 Danish singleton births from 1978 to 1998, cohort members were considered as having a maternal history of anemia if the mother had received...

Association Between Prepartum Maternal Iron Deficiency and Offspring Risk of Schizophrenia: Population-Based Cohort Study With Linkage of Danish National Registers

DEFF Research Database (Denmark)

Sørensen, Holger J; Nielsen, Philip R; Pedersen, Carsten B

2011-01-01

Recent findings suggest that maternal iron deficiency may increase the risk of schizophrenia-spectrum disorder in offspring. We initiated this study to determine whether maternal prepartum anemia influences offspring risk of schizophrenia. We conducted a population-based study with individual...... a 1.60-fold (95% confidence interval = 1.16-2.15) increased risk of schizophrenia. Although the underlying mechanisms are unknown and independent replication is needed, our findings suggest that maternal iron deficiency increases offspring risk of schizophrenia....... record linkage of the Danish Civil Registration System, the Danish Psychiatric Central Register, and the Danish National Hospital Register. In a cohort of 1 115 752 Danish singleton births from 1978 to 1998, cohort members were considered as having a maternal history of anemia if the mother had received...

Pregnancy outcome of threatened abortion with demonstrable fetal cardiac activity: a cohort study.

Science.gov (United States)

Tongsong, T; Srisomboon, J; Wanapirak, C; Sirichotiyakul, S; Pongsatha, S; Polsrisuthikul, T

1995-08-01

Pregnancy with visible fetal heart beat complicated by first trimester threatened abortion had significant increased risk of subsequent spontaneous abortion compared with normal pregnancy. To compare pregnancy outcomes in cases complicated by first trimester threatened abortion with those that were not. Prospective cohort study of 255 cases of first trimester threatened abortions but with visible heart beat and 265 other normal pregnancies. Spontaneous abortion rates of 5.5% (with relative abortal risk of 2.91) was found for study group, compared to 1.88% for controls (p abortion rate than those without.

Cardiovascular Disease Risk in a Large, Population-Based Cohort of Breast Cancer Survivors

NARCIS (Netherlands)

Boekel, Naomi B.; Schaapveld, Michael; Gietema, Jourik A.; Russell, Nicola S.; Poortmans, Philip; Theuws, Jacqueline C. M.; Schinagl, Dominic A. X.; Rietveld, Derek H. F.; Versteegh, Michel I. M.; Visser, Otto; Rutgers, Emiel J. T.; Aleman, Berthe M. P.; van Leeuwen, Flora E.

2016-01-01