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Few biomarker-based validation studies have examined error in online self-report dietary assessment instruments, and food records (FRs) have been considered less than food frequency questionnaires (FFQs) and 24-hour recalls (24HRs). We investigated measurement error in online and paper-based FFQs, online 24HRs, and paper-based FRs in 3 samples drawn primarily from 3 cohorts, comprising 1,393 women and 1,455 men aged 45–86 years. Data collection occurred from January 2011 to October 2013. Attenuation factors and correlation coefficients between reported and true usual intake for energy, protein, sodium, potassium, and respective densities were estimated using recovery biomarkers. Across studies, average attenuation factors for energy were 0.07, 0.07, and 0.19 for a single FFQ, 24HR, and FR, respectively. Correlation coefficients for energy were 0.24, 0.23, and 0.40, respectively. Excluding energy, the average attenuation factors across nutrients and studies were 0.22 for a single FFQ, 0.22 for a single 24HR, and 0.51 for a single FR. Corresponding correlation coefficients were 0.31, 0.34, and 0.53, respectively. For densities (nutrient expressed relative to energy), the average attenuation factors across studies were 0.37, 0.17, and 0.50, respectively. The findings support prior research suggesting different instruments have unique strengths that should be leveraged in epidemiologic research. [ABSTRACT FROM AUTHOR]

The authors assessed the utility and cost-effectiveness of using a World Wide Web-based questionnaire in a large prospective cohort study, the Black Women's Health Study (BWHS). In 1995, 59,000 African-American women were recruited into the BWHS through a paper questionnaire. Follow-up paper questionnaires have been mailed every 2 years since then. During the 2003, 2005, and 2007 questionnaire cycles, participants were given the option of completing a Web-based questionnaire. The cost of developing and processing a returned paper questionnaire was 4 times that of a returned Web questionnaire, primarily because of return postage costs and greater processing time for paper questionnaires. The proportion of respondents who completed a Web questionnaire doubled from 2003 to 2007, from 10.1% to 19.9%, but the characteristics of those completing the Web questionnaire remained the same. Web response was greatest at younger ages (20.9% of those aged <30 years) and declined with age to 3.6% among women aged 60 years or more. Web questionnaires were filled out more completely than paper questionnaires, regardless of the sensitivity of a question. The use of a Web questionnaire in the BWHS resulted in cost savings and more complete responses. Although there are advantages to using a Web questionnaire, the use of multiple means of soliciting questionnaire responses is still needed. [ABSTRACT FROM PUBLISHER]

Medication use is often underreported in paper-based questionnaires or interviews.Web-based questionnaires may improve recall ofmedication use, but data on their validity are currently lacking. Participants in the Pregnancy and Infant Development (PRIDE) Study (2014-2016; n = 557) and the Pregnancy Drug Registry (pREGnant) (2015-2016; n = 169) completed a 6-week paper-based medication diary during gestational weeks 19-24 or 26-31. In week 34, they completed a Web-based questionnaire with questions on medication names, time period and frequency of use, and quantity taken. To assess the degree of underreporting, we calculated the questionnaire's sensitivity using the medication diary as the reference standard. Sensitivity was high formany medication groups, including antiepilepticmedication (sensitivity (Sn) = 0.96, 95% confidence interval (CI): 0.89, 1.00), antacids (Sn = 0.89, 95% CI: 0.86, 0.93), and iron preparations (Sn = 0.81, 95% CI: 0.64, 0.98). However, medications for short-term use were underreported more frequently, with sensitivities of 0.54 (95% CI: 0.35, 0.72) for antihistamines, 0.63 (95% CI: 0.57, 0.69) for analgesic and antipyretic agents, and 0.57 (95% CI: 0.51, 0.64) for acetaminophen. Shortening the period of time between exposure and questionnaire administration increased sensitivity substantially. In conclusion, underreporting in Web-based questionnaires is limited for many medication groups. In prospective studies, underreporting of medications for short-term usemay be reduced by decreasing the interval between consecutive questionnaires. medication use; pregnancy; Pregnancy Drug Registry (pREGnant); Pregnancy and Infant Development (PRIDE) [ABSTRACT FROM AUTHOR]

Two frequently encountered but underrecognized challenges for causal inference in studying the long-term health effects of disasters among survivors include 1) time-varying effects of disasters on a time-to-event outcome and 2) selection bias due to selective attrition. In this paper, we review approaches for overcoming these challenges and demonstrate application of the approaches to a real-world longitudinal data set of older adults who were directly affected by the 2011 Great East Japan Earthquake and Tsunami (n  = 4,857). To illustrate the problem of time-varying effects of disasters, we examined the association between degree of damage due to the tsunami and all-cause mortality. We compared results from Cox regression analysis assuming proportional hazards with those derived using adjusted parametric survival curves allowing for time-varying hazard ratios. To illustrate the problem of selection bias, we examined the association between proximity to the coast (a proxy for housing damage from the tsunami) and depressive symptoms. We corrected for selection bias due to attrition in the 2 postdisaster follow-up surveys (conducted in 2013 and 2016) using multivariable adjustment, inverse probability of censoring weighting, and survivor average causal effect estimation. Our results demonstrate that analytical approaches which ignore time-varying effects on mortality and selection bias due to selective attrition may underestimate the long-term health effects of disasters. [ABSTRACT FROM AUTHOR]

Relationships between some risk factors and breast cancer incidence are known to vary by tumor subtype. However, breast tumors can be classified according to a number of markers, which may be correlated, making it difficult to identify heterogeneity of risk factors with specific tumor markers when using standard competing-risk survival analysis. In this paper, we propose a constrained competing-risk survival model that allows for assessment of heterogeneity of risk factor associations according to specific tumor markers while controlling for other markers. These methods are applied to Nurses’ Health Study data from 1980–2006, during which 3,398 incident invasive breast cancers occurred over 1.4 million person-years of follow-up. Results suggested that when estrogen receptor (ER) and progesterone receptor (PR) status are mutually considered, some risk factors thought to be characteristic of “estrogen-positive tumors,” such as high body mass index during postmenopause and increased height, are actually significantly associated with PR-positive tumors but not ER-positive tumors, while other risk factors thought to be characteristic of “estrogen-negative tumors,” such as late age at first birth, are actually significantly associated with PR-negative rather than ER-negative breast cancer. This approach provides a strategy for evaluating heterogeneity of risk factor associations by tumor marker levels while controlling for additional tumor markers. [ABSTRACT FROM PUBLISHER]

To date, Web-based 24-hour recalls have not been validated using objective biomarkers. From 2006 to 2009, the validity of 6 Web-based DietDay 24-hour recalls was tested among 115 black and 118 white healthy adults from Los Angeles, California, by using the doubly labeled water method, and the results were compared with the results of the Diet History Questionnaire, a food frequency questionnaire developed by the National Cancer Institute. The authors performed repeated measurements in a subset of 53 subjects approximately 6 months later to estimate the stability of the doubly labeled water measurement. The attenuation factors for the DietDay recall were 0.30 for blacks and 0.26 for whites. For the Diet History Questionnaire, the attenuation factors were 0.15 and 0.17 for blacks and whites, respectively. Adjusted correlations between true energy intake and the recalls were 0.50 and 0.47 for blacks and whites, respectively, for the DietDay recall. For the Diet History Questionnaire, they were 0.34 and 0.36 for blacks and whites, respectively. The rate of underreporting of more than 30% of calories was lower with the recalls than with the questionnaire (25% and 41% vs. 34% and 52% for blacks and whites, respectively). These findings suggest that Web-based DietDay dietary recalls offer an inexpensive and widely accessible dietary assessment alternative, the validity of which is equally strong among black and white adults. The validity of the Web-administered recall was superior to that of the paper food frequency questionnaire. [ABSTRACT FROM PUBLISHER]

The aim of this study was to update and validate the Pregnancy Physical Activity Questionnaire (PPAQ), using novel and innovative accelerometer and wearable camera measures in a free-living setting, to improve the measurement performance of this method for self-reporting physical activity. A prospective cohort of 50 eligible pregnant women were enrolled in early pregnancy (mean = 14.9 weeks' gestation). In early, middle, and late pregnancy, participants completed the updated PPAQ and, for 7 days, wore an accelerometer (GT3X-BT; ActiGraph, Pensacola, Florida) on the nondominant wrist and a wearable camera (Autographer; OMG Life (defunct)). At the end of the 7-day period, participants repeated the PPAQ. Spearman correlations between the PPAQ and accelerometer data ranged from 0.37 to 0.44 for total activity, 0.17 to 0.53 for moderate- to vigorous-intensity activity, 0.19 to 0.42 for light-intensity activity, and 0.23 to 0.45 for sedentary behavior. Spearman correlations between the PPAQ and wearable camera data ranged from 0.52 to 0.70 for sports/exercise and from 0.26 to 0.30 for transportation activity. Reproducibility scores ranged from 0.70 to 0.92 for moderate- to vigorous-intensity activity and from 0.79 to 0.91 for sports/exercise, and were comparable across other domains of physical activity. The PPAQ is a reliable instrument and a valid measure of a broad range of physical activities during pregnancy. [ABSTRACT FROM AUTHOR]

The Environmental Influences on Child Health Outcomes (ECHO)-Wide Cohort Study (EWC), a collaborative research design comprising 69 cohorts in 31 consortia, was funded by the National Institutes of Health (NIH) in 2016 to improve children's health in the United States. The EWC harmonizes extant data and collects new data using a standardized protocol, the ECHO-Wide Cohort Data Collection Protocol (EWCP). EWCP visits occur at least once per life stage, but the frequency and timing of the visits vary across cohorts. As of March 4, 2022, the EWC cohorts contributed data from 60,553 children and consented 29,622 children for new EWCP data and biospecimen collection. The median (interquartile range) age of EWCP-enrolled children was 7.5 years (3.7–11.1). Surveys, interviews, standardized examinations, laboratory analyses, and medical record abstraction are used to obtain information in 5 main outcome areas: pre-, peri-, and postnatal outcomes; neurodevelopment; obesity; airways; and positive health. Exposures include factors at the level of place (e.g. air pollution, neighborhood socioeconomic status), family (e.g. parental mental health), and individuals (e.g. diet, genomics). [ABSTRACT FROM AUTHOR]

Follow-up of US cohort members for incident cancer is time-consuming, is costly, and often results in underascertainment when the traditional methods of self-reporting and/or medical record validation are used. We conducted one of the first large-scale investigations to assess the feasibility, methods, and benefits of linking participants in the US Radiologic Technologists (USRT) Study (n  = 146,022) with the majority of US state or regional cancer registries. Follow-up of this cohort has relied primarily on questionnaires (mailed approximately every 10 years) and linkage with the National Death Index. We compared the level of agreement and completeness of questionnaire/death-certificate–based information with that of registry-based (43 registries) incident cancer follow-up in the USRT cohort. Using registry-identified first primary cancers from 1999–2012 as the gold standard, the overall sensitivity was 46.5% for self-reports only and 63.0% for both self-reports and death certificates. Among the 37.0% false-negative reports, 27.8% were due to dropout, while 9.2% were due to misreporting. The USRT cancer reporting patterns differed by cancer type. Our study indicates that linkage to state cancer registries would greatly improve completeness and accuracy of cancer follow-up in comparison with questionnaire self-reporting. These findings support ongoing development of a national US virtual pooled registry with which to streamline cohort linkages. [ABSTRACT FROM AUTHOR]

The Dietary Guidelines for Americans rely on summaries of the effect of dietary pattern on disease risk, independent of other population characteristics. We explored the modifying effect of prepregnancy body mass index (BMI; weight (kg)/height (m)2) on the relationship between fruit and vegetable density (cup-equivalents/1,000 kcal) and preeclampsia using data from a pregnancy cohort study conducted at 8 US medical centers (n  = 9,412; 2010–2013). Usual daily periconceptional intake of total fruits and total vegetables was estimated from a food frequency questionnaire. We quantified the effects of diets with a high density of fruits (≥1.2 cups/1,000 kcal/day vs. <1.2 cups/1,000 kcal/day) and vegetables (≥1.3 cups/1,000 kcal/day vs. <1.3 cups/1,000 kcal/day) on preeclampsia risk, conditional on BMI, using a doubly robust estimator implemented in 2 stages. We found that the protective association of higher fruit density declined approximately linearly from a BMI of 20 to a BMI of 32, by 0.25 cases per 100 women per each BMI unit, and then flattened. The protective association of higher vegetable density strengthened in a linear fashion, by 0.3 cases per 100 women for every unit increase in BMI, up to a BMI of 30, where it plateaued. Dietary patterns with a high periconceptional density of fruits and vegetables appear more protective against preeclampsia for women with higher BMI than for leaner women. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been associated with earlier natural menopause; however, the underlying mechanisms are not well understood, particularly the extent to which this relationship is mediated by sex hormones. We analyzed data (1999–2017) on 1,120 premenopausal women from the Study of Women's Health Across the Nation (SWAN). Causal mediation analysis was applied to quantify the degree to which follicle-stimulating hormone (FSH) and estradiol levels could mediate the associations between PFAS and incident natural menopause. Participants with higher PFAS concentrations had shorter times to natural menopause, with a relative survival of 0.82 (95% confidence interval (CI): 0.69, 0.96) for linear perfluorooctane sulfonate (n-PFOS), 0.84 (95% CI: 0.69, 1.00) for sum of branched-chain perfluorooctane sulfonate (Sm-PFOS), 0.79 (95% CI: 0.66, 0.93) for linear-chain perfluorooctanoate (n-PFOA), and 0.84 (95% CI: 0.71, 0.97) for perfluorononanoate (PFNA), comparing the highest tertile of PFAS concentrations with the lowest. The proportion of the effect mediated through FSH was 8.5% (95% CI: −11.7, 24.0) for n-PFOS, 13.2% (95% CI: 0.0, 24.5) for Sm-PFOS, 26.9% (95% CI: 15.6, 38.4) for n-PFOA, and 21.7% (6.8, 37.0) for PFNA. No significant mediation by estradiol was observed. The effect of PFAS on natural menopause may be partially explained by variations in FSH concentrations. [ABSTRACT FROM AUTHOR]

Whereas the feasibility and effectiveness of Internet-based epidemiologic research have been established, methodological support for the quality of such data is still accumulating. We aimed to identify sociodemographic differences among members of a French cohort according to willingness to provide part of one's 15-digit national identification number (personal Social Security number (PSSN)) and to assess response consistency based on information reported on the sociodemographic questionnaire and that reflected in the PSSN. We studied 100,118 persons enrolled in an Internet-based prospective cohort study, the NutriNet-Santé Study, between 2009 and 2013. Persons aged 18 years or more who resided in France and had Internet access were eligible for enrollment. The sociodemographic profiles of participants with discordant data were compared against those of participants with concordant data via 2-sided polytomous logistic regression. In total, 84,442 participants (84.3%) provided the first 7 digits of their PSSN, and among them 5,141 (6.1%) had discordant data. Our multivariate analysis revealed differences by sex, age, education, and employment as regards response consistency patterns. The results support the quality of sociodemographic data obtained online from a large and diverse volunteer sample. The quantitative description of participant profiles according to response consistency patterns could inform future methodological work in e-epidemiology. [ABSTRACT FROM AUTHOR]

In Australia, as in many industrialized countries, the past 50 years have been marked by increasing female labor-force participation. It is popularly speculated that this might impose a mental-health burden on women and their children. This analysis aimed to examine the associations between household labor-force participation (household employment configuration) and the mental health of parents and children. Seven waves of data from the Longitudinal Study of Australian Children were used, comprising 2004–2016, with children aged 4–17 years). Mental health outcome measures were the Strengths and Difficulties Questionnaire (children/adolescents) and 6-item Kessler Psychological Distress Scale (parents). A 5-category measure of household employment configuration was derived from parental reports: both parents full-time, male-breadwinner, female-breadwinner, shared-part-time employment (both part-time) and father full-time/mother part-time (1.5-earner). Fixed-effects regression models were used to compare within-person effects, controlling for time-varying confounders. For men, the male-breadwinner configuration was associated with poorer mental health compared with the 1.5-earner configuration (β = 0.21, 95% confidence interval: 0.05, 0.36). No evidence of association was observed for either women or children. This counters prevailing social attitudes, suggesting that neither children nor women are adversely affected by household employment configuration, nor are they disadvantaged by the extent of this labor-force participation. Men's mental health appears to be poorer when they are the sole household breadwinner. [ABSTRACT FROM AUTHOR]

Our aim in this study was to estimate the strength of associations between prenatal diet quality and child behavioral, language, and motor functions in the Norwegian Mother and Child Cohort Study (1999–2008). We created a prenatal diet quality index (PDQI) based on adherence to Norwegian dietary guidelines. Child outcomes were defined as sum scores on the Child Behavior Checklist, the Ages and Stages Questionnaire, and the Child Development Index at ages 18, 36, and 60 months. Using a longitudinal cohort study design and Bayesian hierarchical modeling, we estimated association strengths using inverse probability weighting to account for selection bias. In total, 27,529 mother-child pairs were eligible for inclusion. A 1–standard-deviation increase in PDQI score was associated with an absolute reduction in outcome sum scores of 0.02–0.21 and a 3%–7% relative decrease, with larger decreases seen for language and motor functions than for behavioral functions. PDQI scores were inversely associated with all child functions, but the estimated strength of each association was low. The results indicate that the observed variations in PDQI scores in an industrialized Western society may not profoundly influence the child functions studied. [ABSTRACT FROM AUTHOR]

We describe the design, implementation, and results of the Qatar Biobank (QBB) cohort study for the first 10,000 participants. QBB is a prospective, population-based cohort study in Qatar, established in 2012. QBB's primary goal was to establish a cohort accessible to the local and international scientific community, providing adequate health data and biological samples to enable evidence-based research. The study design is based on an agnostic hypothesis, collecting data using questionnaires, biological samples, imaging data, and -omics. QBB aims to recruit 60,000 participants, men and women, adult (aged ≥18 years) Qataris or long-term residents (≥15 years living in Qatar) and follow up with them every 5 years. Currently, QBB has reached 28% (n = 17,065) of the targeted enrollee population and more than 2 million biological samples. QBB is a multinational cohort including 33 different nationalities, with a relatively young population (mean age, 40.5 years) of persons who are highly educated (50% university-educated) and have high monthly incomes. The 4 main noncommunicable diseases found among the QBB population are dyslipidemia, diabetes, hypertension, and asthma with prevalences of 30.1%, 17.4%, 16.8%, and 9.1%, respectively. The QBB repository can provide data and biological samples sufficient to demonstrate valid associations between genetic and/or environmental exposure and disease development to scientists worldwide. [ABSTRACT FROM AUTHOR]

We used marginal structural models to evaluate associations of social support with antepartum depression in late pregnancy, if everyone had had high social support both before pregnancy and during early pregnancy, compared with having low social support at one of the 2 time points or low social support at both time points. In 2012–2014, pregnant Peruvian women (n = 3,336) were recruited into a prospective cohort study (at a mean gestational age of 9 weeks). A follow-up interview (n = 2,279) was conducted (at 26–28 weeks of gestation). Number of available support providers and satisfaction with social support were measured using Sarason Social Support Questionnaire–6. Depression was measured using the Edinburgh Postnatal Depression Scale. Low number of support providers at both time points was associated with increased risk of depression (odds ratio = 1.62, 95% confidence interval: 1.12, 2.34). The association for low satisfaction at both time points was marginally significant (odds ratio = 1.41, 95% confidence interval: 0.99, 1.99). Depression risk was not significantly higher for women who reported high social support at one of the 2 time points. Our study reinforces the importance of assessing social support before and during pregnancy and underscores the need for future interventions targeted at increasing the number of support providers to prevent antepartum depression. [ABSTRACT FROM AUTHOR]

Dietary protein may help prevent age-related declines in strength and functional capacity. This study examines the independent relationship between dietary protein and longitudinal changes in physical functioning among adults participating in the Framingham Offspring Study from examination 5 (1991-1995) to examination 8 (2005-2008). Protein intakes were derived from 3-day diet records during examinations 3 and 5; functional status was determined over 12 years using 7 items selected from standardized questionnaires. Multivariable models adjusted for age, sex, education, physical activity, smoking, height, and energy intake. Functional tasks that benefitted most from a higher-protein diet (≥1.2 g/kg/day vs. <0.8 g/kg/day) were doing heavy work at home, walking 1/2 mile (0.8 km), going up and down stairs, stooping/kneeling/crouching, and lifting heavy items. Those with higher protein intakes were 41% less likely (95% CI: 0.43, 0.82) to become dependent in 1 or more of the functional tasks over follow-up. Higher physical activity and lower body mass index were both independently associated with less functional decline. The greatest risk reductions were found among those with higher protein intakes combined with either higher physical activity, more skeletal muscle mass, or lower body mass index. This study demonstrates that dietary protein intakes above the current US Recommended Daily Allowance may slow functional decline in older adults. [ABSTRACT FROM AUTHOR]

We assessed associations between modeled and perceived exposure to radiofrequency electromagnetic fields (RF-EMF) from mobile-phone base stations and the development of nonspecific symptoms and sleep disturbances over time. A population-based Dutch cohort study, the Occupational and Environmental Health Cohort Study (AMIGO) (n = 14,829; ages 31-65 years), was established in 2011/2012 (T0), with follow-up of a subgroup (n = 3,992 invited) in 2013 (T1; n = 2,228) and 2014 (T2; n = 1,740). We modeled far-field RF-EMF exposure from mobile-phone base stations at the home addresses of the participants using a 3-dimensional geospatial model (NISMap). Perceived exposure (0 = not at all; 6 = very much), nonspecific symptoms, and sleep disturbances were assessed by questionnaire. We performed cross-sectional and longitudinal analyses, including fixed-effects regression. We found small correlations between modeled and perceived exposure in AMIGO participants at baseline (n = 14,309; rSpearman = 0.10). For 222 follow-up participants, modeled exposure increased substantially (>0.030 mW/m²) between T0 and T1. This increase in modeled exposure was associated with an increase in perceived exposure during the same time period. In contrast to modeled RF-EMF exposure from mobile-phone base stations, perceived exposure was associated with higher symptom reporting scores in both cross-sectional and longitudinal analyses, as well as with sleep disturbances in cross-sectional analyses. [ABSTRACT FROM AUTHOR]

Initially submitted February 1, 2016; accepted for publication August 4, 2016. The ability to classify people according to their underlying genetic susceptibility to a disease is increasing with new knowledge, better family data, and more sophisticated risk prediction models, allowing for more effective prevention and screening. To do so, however, we need to know whether risk associations are the same for people with different genetic susceptibilities. To illustrate one way to estimate such gene-environment interactions, we used prospective data from 3 Australian family cancer cohort studies, 2 enriched for familial risk of breast cancer. There were 288 incident breast cancers in 9,126 participants from 3,222 families. We used Cox proportional hazards models to investigate whether associations of breast cancer with body mass index (BMI; weight (kg)/height (m)2) at age 18-21 years, BMI at baseline, and change in BMI differed according to genetic risk based on lifetime breast cancer risk from birth, as estimated by BOADICEA (Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm) software, adjusted for age at baseline data collection. Although no interactions were statistically significant, we have demonstrated the power with which gene-environment interactions can be investigated using a cohort enriched for persons with increased genetic risk and a continuous measure of genetic risk based on family history. [ABSTRACT FROM AUTHOR]

Growing evidence has linked positive psychological attributes like optimism to a lower risk of poor health outcomes, especially cardiovascular disease. It has been demonstrated in randomized trials that optimism can be learned. If associations between optimism and broader health outcomes are established, it may lead to novel interventions that improve public health and longevity. In the present study, we evaluated the association between optimism and cause-specific mortality in women after considering the role of potential confounding (sociodemo-graphic characteristics, depression) and intermediary (health behaviors, health conditions) variables. We used prospective data from the Nurses' Health Study (n = 70,021). Dispositional optimism was measured in 2004; all-cause and cause-specific mortality rates were assessed from 2006 to 2012. Using Cox proportional hazard models, we found that a higher degree of optimism was associated with a lower mortality risk. After adjustment for sociode-mographic confounders, compared with women in the lowest quartile of optimism, women in the highest quartile had a hazard ratio of 0.71 (95% confidence interval: 0.66, 0.76) for all-cause mortality. Adding health behaviors, health conditions, and depression attenuated but did not eliminate the associations (hazard ratio = 0.91, 95% confidence interval: 0.85, 0.97). Associations were maintained for various causes of death, including cancer, heart disease, stroke, respiratory disease, and infection. Given that optimism was associated with numerous causes of mortality, it may provide a valuable target for new research on strategies to improve health. [ABSTRACT FROM AUTHOR]

Obesity is a major health problem in the United States and a growing concern among members of the military. Posttraumatic stress disorder (PTSD) has been associated with overweight and obesity and may increase the risk of those conditions among military service members. Disordered eating behaviors have also been associated with PTSD and weight gain. However, eating disorders remain understudied in military samples. We investigated longitudinal associations among PTSD, disordered eating, and weight gain in the Millennium Cohort Study, which includes a nationally representative sample of male (n = 27,741) and female (n = 6,196) service members. PTSD at baseline (time 1; 2001-2003) was associated with disordered eating behaviors at time 2 (2004-2006), as well as weight change from time 2 to time 3 (2007-2008). Structural equation modeling results revealed that the association between PTSD and weight change from time 2 to time 3 was mediated by disordered eating symptoms. The association between PTSD and weight gain resulting from compensatory behaviors (vomiting, laxative use, fasting, overexercise) was significant for white participants only and for men but not women. PTSD was both directly and indirectly (through disordered eating) associated with weight change. These results highlight potentially important demographic differences in these associations and emphasize the need for further investigation of eating disorders in military service members. [ABSTRACT FROM AUTHOR]

Concerns about high caffeine intake and coffee as a vehicle for added fat and sugar have raised questions about the net impact of coffee on health. Although inverse associations have been observed for overall mortality, data for cause-specific mortality are sparse. Additionally, few studies have considered exclusively decaffeinated coffee intake or use of coffee additives. Coffee intake was assessed at baseline by self-report in the Prostate, Lung, Colo-rectal and Ovarian Cancer Screening Trial. Hazard ratios were estimated using Cox proportional hazards models. Among 90,317 US adults without cancer at study baseline (1998-2001) or history of cardiovascular disease at study enrollment (1993-2001), 8,718 deaths occurred during 805,644 person-years of follow-up from 1998 through 2009. Following adjustment for smoking and other potential confounders, coffee drinkers, as compared with nondrinkers, had lower hazard ratios for overall mortality (<1 cup/day: hazard ratio (HR) = 0.99 (95% confidence interval (CI): 0.92, 1.07); 1 cup/day: HR = 0.94 (95% CI: 0.87, 1.02); 2-3 cups/day: HR = 0.82 (95% CI: 0.77, 0.88); 4-5 cups/ day: HR = 0.79 (95% CI: 0.72, 0.86); ≥6 cups/day: HR = 0.84 (95% CI: 0.75, 0.95)). Similar findings were observed for decaffeinated coffee and coffee additives. Inverse associations were observed for deaths from heart disease, chronic respiratory diseases, diabetes, pneumonia and influenza, and intentional self-harm, but not cancer. Coffee may reduce mortality risk by favorably affecting inflammation, lung function, insulin sensitivity, and depression. [ABSTRACT FROM AUTHOR]

This study's objective was to investigate healthy aging in older French adults 5 years after a period of daily nutritional-dose supplementation with antioxidant nutrients. The study was based on the double-blind, randomized trial, Supplementation with Antioxidant Vitamins and Minerals (SU.VI.MAX) Study (1994-2002) and the SU.VI.MAX 2 Follow-up Study (2007-2009). During 1994-2002, participants received a daily combination of vitamin C (120 mg), β-carotene (6 mg), vitamin E (30 mg), selenium (100 µg), and zinc (20 mg) or placebo. Healthy aging was assessed in 2007-2009 by using multiple criteria, including the absence of major chronic disease and good physical and cognitive functioning. Data from a subsample of the SU.VI.MAX 2 cohort, initially free of major chronic disease, with a mean age of 65.3 years in 2007-2009 (n = 3,966), were used to calculate relative risks. Supplementation was associated with a greater healthy aging probability among men (relative risk = 1.16, 95% confidence interval: 1.04, 1.29) but not among women (relative risk = 0.98, 95%confidence interval: 0.86, 1.11) or all participants (relative risk = 1.07, 95%confidence interval: 0.99, 1.16). Moreover, exploratory subgroup analyses indicated effect modification by initial serum concentrations of zinc and vitamin C. In conclusion, an adequate supply of antioxidant nutrients (equivalent to quantities provided by a balanced diet rich in fruits and vegetables) may have a beneficial role for healthy aging. [ABSTRACT FROM AUTHOR]

The extent to which social relationships influence cognitive aging is unclear. In this study, we investigated the association of midlife quality of close relationships with subsequent cognitive decline. Participants in the Whitehall II Study (n = 5,873; ages 45–69 years at first cognitive assessment) underwent executive function and memory tests 3 times over a period of 10 years (1997–1999 to 2007–2009). Midlife negative and positive aspects of close relationships were assessed twice using the Close Persons Questionnaire during the 8 years preceding cognitive assessment. Negative aspects of close relationships, but not positive aspects, were associated with accelerated cognitive aging. Participants in the top third of reported negative aspects of close relationships experienced a faster 10-year change in executive function (−0.04 standard deviation, 95% confidence interval: −0.08, −0.01) than those in the bottom third, which was comparable with 1 extra year of cognitive decline for participants aged 60 years after adjustment for sociodemographic and health status. Longitudinal analysis found no evidence of reverse causality. This study highlights the importance of differentiating aspects of social relationships to evaluate their unique associations with cognitive aging. [ABSTRACT FROM PUBLISHER]

Early detection of subjects at high risk of developing dementia is essential. By dealing with censoring and competing risk of death, we developed a score for predicting 10-year dementia risk by combining cognitive tests, and we assessed whether inclusion of cognitive change over the previous year increased its discrimination. Data came from the French prospective cohort study Personnes Agées QUID (PAQUID) and included 3,777 subjects aged 65 years or older (1988–1998). The combined prediction score was estimated by means of an illness-death model handling interval censoring and competing risk of death. Its predictive ability was measured using the receiver operating characteristic (ROC) curve, with 2 different definitions depending on the way subjects who died without a dementia diagnosis were considered. To account for right-censoring and interval censoring, we estimated the ROC curves by means of a weighting approach and a model-based imputation estimator. The combined score exhibited an area under the ROC curve (AUROC) of 0.81 for discriminating future demented subjects from subjects alive and nondemented 10 years later and an AUROC of 0.75 for discriminating future demented subjects from all other subjects (including deceased persons). Adjustment for cognitive change over the previous year did not improve prediction. [ABSTRACT FROM PUBLISHER]

Poor diet quality is thought to be a leading risk factor for years of life lost. We examined how scores on 4 commonly used diet quality indices—the Healthy Eating Index 2010 (HEI), the Alternative Healthy Eating Index 2010 (AHEI), the Alternate Mediterranean Diet (aMED), and the Dietary Approaches to Stop Hypertension (DASH)—are related to the risks of death from all causes, cardiovascular disease (CVD), and cancer among postmenopausal women. Our prospective cohort study included 63,805 participants in the Women's Health Initiative Observational Study (from 1993–2010) who completed a food frequency questionnaire at enrollment. Cox proportional hazards models were fit using person-years as the underlying time metric. We estimated multivariate hazard ratios and 95% confidence intervals for death associated with increasing quintiles of diet quality index scores. During 12.9 years of follow-up, 5,692 deaths occurred, including 1,483 from CVD and 2,384 from cancer. Across indices and after adjustment for multiple covariates, having better diet quality (as assessed by HEI, AHEI, aMED, and DASH scores) was associated with statistically significant 18%–26% lower all-cause and CVD mortality risk. Higher HEI, aMED, and DASH (but not AHEI) scores were associated with a statistically significant 20%–23% lower risk of cancer death. These results suggest that postmenopausal women consuming a diet in line with a priori diet quality indices have a lower risk of death from chronic disease. [ABSTRACT FROM PUBLISHER]

Lifetime exposures to adverse social environments influence adult health, as do exposures in early life. It is usual to examine the influences of school on teenage health and of adult area of residence on adult health. We examined the combined long-term association of the school attended, as well as the area of residence in childhood, with adult health. A total of 6,285 children from Aberdeen, Scotland, who were aged 5–12 years in 1962, were followed up at a mean age of 47 years in 2001. Cross-classified multilevel logistic regression was used to estimate the associations of family, school, and area of residence with self-reported adult health and mental health, adjusting for childhood family-, school-, and neighborhood-level factors, as well as current adult occupational position. Low early-life social position (as determined by the father's occupational level) was associated with poor adult self-rated health but not poor mental health. There were small contextual associations between childhood school environment (median odds ratio = 1.08) and neighborhood environment (median odds ratio = 1.05) and adult self-rated health. The share of the total variance in health at the family level was 10.1% compared with 89.6% at the individual level. Both socioeconomic context and composition in early life appear to have an influence on adult health, even after adjustment for current occupational position. [ABSTRACT FROM PUBLISHER]

Intake of n-3 and n-6 polyunsaturated fatty acids (PUFAs) has been implicated in the pathogenesis of depression. We sought to estimate the association between intake of fish and n-3 and n-6 PUFAs and suicide mortality over the course of long-term follow-up. In this prospective cohort study, biennial questionnaires were administered to 42,290 men enrolled in the Health Professionals Follow-up Study (1988–2008), 72,231 women enrolled in the Nurses' Health Study (1986–2008), and 90,836 women enrolled in Nurses' Health Study II (1993–2007). Dietary fish and n-3 and n-6 PUFA intakes were assessed every 4 years using a validated food-frequency questionnaire. Suicide mortality was ascertained through blind physician review of death certificates and hospital or pathology reports. Adjusted relative risks of suicide mortality were estimated with multivariable Cox proportional hazards models and pooled across cohorts using random-effects meta-analysis. The pooled multivariable relative risks for suicide among persons in the highest quartile of intake of n-3 or n-6 PUFAs, relative to the lowest quartile, ranged from 1.08 to 1.46 for n-3 PUFAs (Ptrend = 0.11–0.52) and from 0.68 to 1.19 for n-6 PUFAs (Ptrend = 0.09–0.54). We did not find evidence that intake of n-3 PUFAs or fish lowered the risk of completed suicide. [ABSTRACT FROM PUBLISHER]

Higher dietary intakes of flavonoids and proanthocyanidins have been associated with a lower risk of several cancers. Few prospective epidemiologic studies have examined individual flavonoids and proanthocyanidins in relation to prostate cancer. We examined these associations in a prospective US cohort of 43,268 men with a mean age of 70 years who completed detailed self-administered questionnaires in 1999–2000. During a mean follow-up of 7.8 years, 3,974 total prostate cancers, including 567 high-grade cases and 362 advanced cases, were ascertained. Cox proportional hazards regression models were used to calculate multivariable-adjusted relative risks and 95% confidence intervals. Residual energy-adjusted total flavonoids (for fifth quintile vs. first quintile, relative risk = 1.11, 95% confidence interval: 1.01, 1.23; P for trend = 0.02) and several subclasses were positively associated with overall prostate cancer risk, mostly limited to the top quintile and the first 2 years of follow-up. The associations for total flavonoids, flavan-3-ols, and proanthocyanidins with high-grade prostate cancer risk varied by follow-up time. During follow-up from 2002 to 2009, we observed suggestive inverse trends with higher total flavonoids (P for trend = 0.05) and proanthocyanidins (P for trend = 0.04) with high-grade prostate cancer, but not with advanced prostate cancer. Although evidence is limited, a possible role of total flavonoids and proanthocyanidins in prostate cancer tumor progression deserves further study. [ABSTRACT FROM PUBLISHER]

We assessed the relation of experiences of racism to the incidence of obesity and the modifying impact of residential racial segregation in the Black Women's Health Study, a follow-up study of US black women. Racism scores were created from 8 questions asked in 1997 and 2009 about the frequency of “everyday” racism (e.g., “people act as if you are dishonest”) and of “lifetime” racism (e.g., unfair treatment on the job). Residential segregation was measured by linking participant addresses to 2000 and 2010 US Census block group data on the percent of black residents. We used Cox proportional hazard models to estimate incidence rate ratios and 95% confidence intervals. Based on 4,315 incident cases of obesity identified from 1997 through 2009, both everyday racism and lifetime racism were positively associated with increased incidence. The incidence rate ratios for women who were in the highest category of everyday racism or lifetime racism in both 1997 and 2009, relative to those in the lowest category, were 1.69 (95% confidence interval: 1.45, 1.96; Ptrend < 0.01) and 1.38 (95% confidence interval: 1.15, 1.66; Ptrend < 0.01), respectively. These associations were not modified by residential segregation. These results suggest that racism contributes to the higher incidence of obesity among African American women. [ABSTRACT FROM AUTHOR]

A long-term cohort study of working men in Israel found that smokers who reduced their cigarette consumption had lower subsequent mortality rates than those who did not. We conducted comparable analyses in 2 populations of smokers in Scotland. The Collaborative Study included 1,524 men and women aged 40–65 years in a working population who were screened twice, in 1970–1973 and 1977. The Renfrew/Paisley Study included 3,730 men and women aged 45–64 years in a general population who were screened twice, in 1972–1976 and 1977–1979. Both groups were followed up through 2010. Subjects were categorized by smoking intensity at each screening as smoking 0, 1–10, 11–20, or ≥21 cigarettes per day. At the second screening, subjects were categorized as having increased, maintained, or reduced their smoking intensity or as having quit smoking between the first and second screenings. There was no evidence of lower mortality in all reducers compared with maintainers. Multivariate adjusted hazard ratios of mortality were 0.91 (95% confidence interval (CI): 0.75, 1.10) in the Collaborative Study and 1.08 (95% CI: 0.97, 1.20) in the Renfrew/Paisley Study. There was clear evidence of lower mortality among quitters in both the Collaborative Study (hazard ratio = 0.66, 95% CI: 0.56, 0.78) and the Renfrew/Paisley Study (hazard ratio = 0.75, 95% CI: 0.67, 0.84). In the Collaborative Study only, we observed lower mortality similar to that of quitters among heavy smokers (≥21 cigarettes/day) who reduced their smoking intensity. These inconclusive results support the view that reducing cigarette consumption should not be promoted as a means of reducing mortality, although it may have a valuable role as a step toward smoking cessation. [ABSTRACT FROM PUBLISHER]

Dyslipidemia and chronic inflammation may play a role in the cause of lower urinary tract symptoms (LUTS) in older men. Use of statin drugs, which are prescribed to lower cholesterol and appear to reduce inflammation, may decrease the incidence or progression of LUTS. The associations of statin drug use with LUTS incidence and progression were prospectively evaluated in the Health Professionals Follow-up Study from 1992 to 2008. Hazard ratios and 95% confidence intervals of incident LUTS (from no or a low International Prostate Symptom Score (IPSS) of 0–7 to a moderate or worse IPSS of ≥15; n = 5,790 cases in 24,715 men) and of LUTS progression (from modest IPSS of 8–14 to severe IPSS of ≥20; n = 2,238 cases in 8,709 men) were calculated comparing current statin use with nonuse. The hazard ratios of LUTS incidence and progression comparing current use to nonuse were greater than 1. However, when comparisons were restricted to participants who used drugs to treat hypertension (a surrogate for uptake of medical care), statin use was not associated with LUTS incidence (hazard ratio = 1.02, 95% confidence interval: 0.94, 1.12) or progression (hazard ratio = 0.98, 95% confidence interval: 0.85, 1.13). Thus, statin use is unlikely to beneficially influence the development or course of LUTS. The present study highlights a methodological issue (confounding) that must be addressed in observational studies on the use of common drugs for indications other than the primary use. [ABSTRACT FROM PUBLISHER]

Overweight is associated with a reduced health-related quality of life (QOL), but less is known about the impact of long-term body mass index (BMI, calculated as weight (kg)/height (m)2) patterns on QOL in adults. In the Dutch Doetinchem Cohort Study (1989–2009) that included 1,677 men and 1,731 women aged 20–66 years, 6 BMI patterns were defined by using 4 measurements over a 15-year period: 1) persistent healthy weight (18.5–24.9, reference pattern); 2) persistent overweight (25.0–29.9); 3) persistent obesity (≥30.0); 4) developing overweight; 5) developing obesity; and 6) switching between BMI categories. For each BMI pattern, adjusted QOL (measured on a 0–100 scale) was estimated at the end of this period. The lowest QOL was observed for persistent obesity of all BMI patterns. It was 5.0 points (P = 0.02) lower for 1 mental dimension in men and 6.2–11.6 points (P < 0.05) lower for 5 (mainly physical) dimensions in women. Developing overweight or obesity scored 1.8–6.3 points (P < 0.05) lower on 2–5 (mainly physical) dimensions. Persistent overweight hardly differed from a persistent healthy weight. In women, switching between BMI categories resulted in a lower QOL on the mental dimensions. Studying long-term BMI patterns over a 15-year period showed that persistent obesity, developing overweight, and developing obesity resulted in a lower QOL—particularly on the physical dimensions—compared with a persistent healthy weight. [ABSTRACT FROM PUBLISHER]

Investigators in the Chicago Healthy Aging Study (CHAS) reexamined 1,395 surviving participants aged 65–84 years (28% women) from the Chicago Heart Association Detection Project in Industry (CHA) 1967–1973 cohort whose cardiovascular disease (CVD) risk profiles were originally ascertained at ages 25–44 years. CHAS investigators reexamined 421 participants who were low-risk (LR) at baseline and 974 participants who were non-LR at baseline. LR was defined as having favorable levels of 4 major CVD risk factors: serum total cholesterol level <200 mg/dL and no use of cholesterol-lowering medication; blood pressure 120/≤80 mm Hg and no use of antihypertensive medication; no current smoking; and no history of diabetes or heart attack. While the potential of LR status in overcoming the CVD epidemic is being recognized, the long-term association of LR with objectively measured health in older age has not been examined. It is hypothesized that persons who were LR in 1967–1973 and have survived to older age will have less clinical and subclinical CVD, lower levels of inflammatory markers, and better physical performance/functioning and sleep quality. Here we describe the rationale, objectives, design, and implementation of this longitudinal epidemiologic study, compare baseline and follow-up characteristics of participants and nonparticipants, and highlight the feasibility of reexamining study participants after an extended period postbaseline with minimal interim contact. [ABSTRACT FROM AUTHOR]

Animal models indicate that exposure to choline in utero improves visual memory through cholinergic transmission and/or epigenetic mechanisms. Among 895 mothers in Project Viva (eastern Massachusetts, 1999–2002 to 2008–2011), we estimated the associations between intakes of choline, vitamin B12, betaine, and folate during the first and second trimesters of pregnancy and offspring visual memory (measured by the Wide Range Assessment of Memory and Learning, Second Edition (WRAML2), Design and Picture Memory subtests) and intelligence (measured using the Kaufman Brief Intelligence Test, Second Edition (KBIT-2)) at age 7 years. Mean second-trimester intakes were 328 (standard deviation (SD), 63) mg/day for choline, 10.5 (SD, 5.1) µg/day for vitamin B12, 240 (SD, 104) mg/day for betaine, and 1,268 (SD, 381) µg/day for folate. Mean age 7 test scores were 17.2 (SD, 4.4) points on the WRAML 2 Design and Picture Memory subtests, 114.3 (SD, 13.9) points on the verbal KBIT-2, and 107.8 (SD, 16.5) points on the nonverbal KBIT-2. In a model adjusting for maternal characteristics, the other nutrients, and child's age and sex, the top quartile of second-trimester choline intake was associated with a child WRAML2 score 1.4 points higher (95% confidence interval: 0.5, 2.4) than the bottom quartile (P-trend = 0.003). Results for first-trimester intake were in the same direction but weaker. Intake of the other nutrients was not associated with the cognitive tests administered. Higher gestational choline intake was associated with modestly better child visual memory at age 7 years. [ABSTRACT FROM PUBLISHER]

Systematic investigations into the structure of measurement error of physical activity questionnaires are lacking. We propose a measurement error model for a physical activity questionnaire that uses physical activity level (the ratio of total energy expenditure to basal energy expenditure) to relate questionnaire-based reports of physical activity level to true physical activity levels. The 1999–2006 National Health and Nutrition Examination Survey physical activity questionnaire was administered to 433 participants aged 40–69 years in the Observing Protein and Energy Nutrition (OPEN) Study (Maryland, 1999–2000). Valid estimates of participants’ total energy expenditure were also available from doubly labeled water, and basal energy expenditure was estimated from an equation; the ratio of those measures estimated true physical activity level (“truth”). We present a measurement error model that accommodates the mixture of errors that arise from assuming a classical measurement error model for doubly labeled water and a Berkson error model for the equation used to estimate basal energy expenditure. The method was then applied to the OPEN Study. Correlations between the questionnaire-based physical activity level and truth were modest (r = 0.32–0.41); attenuation factors (0.43–0.73) indicate that the use of questionnaire-based physical activity level would lead to attenuated estimates of effect size. Results suggest that sample sizes for estimating relationships between physical activity level and disease should be inflated, and that regression calibration can be used to provide measurement error–adjusted estimates of relationships between physical activity and disease. [ABSTRACT FROM PUBLISHER]

Latent class models are useful for classifying subjects by dietary patterns. Our goals were to use latent transition models to identify dietary patterns during pregnancy and postpartum, to estimate the prevalence of these dietary patterns, and to model transition probabilities between dietary patterns as a function of covariates. Women who were enrolled in the Pregnancy, Infection, and Nutrition Study (University of North Carolina, 2000–2005) were followed for 1 year postpartum, and their diets were assessed in the second trimester and at 3 and 12 months postpartum (n = 519, 484, and 374, respectively) by using a food frequency questionnaire. After adjusting for energy intake, parity, smoking status, race, and education, we identified 3 dietary patterns and named them “prudent,” “health conscious Western,” and “Western.” Nulliparas were 2.9 and 2.1 times more likely to be in the “prudent” class than the “health conscious Western” or the “Western” class, respectively. The 3 dietary patterns were very stable, with the “health conscious Western” class being the least stable; the probability for staying in the same class was 0.74 and 0.87 at 3 and 12 months postpartum, respectively. Breastfeeding mothers were more likely than nonbreastfeeding mothers to switch dietary pattern class (P = 0.0286). Except for breastfeeding mothers, most women did not switch dietary patterns from pregnancy to postpartum. [ABSTRACT FROM PUBLISHER]

Reserve and National Guard forces have been mobilized to an unprecedented degree in recent overseas conflicts. There is concern that rates of psychological problems may continue to rise for many years after deployment. The authors conducted a cohort study of 552 United Kingdom Reservists who deployed to Iraq in 2003 and 391 nondeployed Reservists. Measures of mental health and social functioning were collected a mean of 16 months and 4.8 years after return from possible deployment. At the first follow-up, deployment was associated with increased common mental disorder, post-traumatic stress disorder (PTSD), and poor general health. By the second follow-up, those who had deployed were no longer at increased risk for common mental disorder or poor general health and had good levels of social functioning. However, those who deployed continued to have over twice the odds of PTSD (odds ratio = 2.42, 95% confidence interval: 1.04, 5.62) and were more likely to report actual or serious consideration of separation from their partner. In conclusion, the authors found that the majority of mental health and social problems following deployment are transient. However, Reservists who deployed in the Iraq War remain at increased risk of PTSD and relationship problems 5 years after their tour of duty. [ABSTRACT FROM AUTHOR]

Unfavorable work characteristics, such as low job control and too high or too low job demands, have been suggested to increase the likelihood of physical inactivity during leisure time, but this has not been verified in large-scale studies. The authors combined individual-level data from 14 European cohort studies (baseline years from 1985-1988 to 2006-2008) to examine the association between unfavorable work characteristics and leisure-time physical inactivity in a total of 170,162 employees (50% women; mean age, 43.5 years). Of these employees, 56,735 were reexamined after 2-9 years. In cross-sectional analyses, the odds for physical inactivity were 26% higher (odds ratio = 1.26, 95% confidence interval: 1.15, 1.38) for employees with high-strain jobs (low control/high demands) and 21% higher (odds ratio = 1.21, 95% confidence interval: 1.11, 1.31) for those with passive jobs (low control/low demands) compared with employees in low-strain jobs (high control/low demands). In prospective analyses restricted to physically active participants, the odds of becoming physically inactive during follow-up were 21% and 20% higher for those with high-strain (odds ratio = 1.21, 95% confidence interval: 1.11, 1.32) and passive (odds ratio= 1.20, 95% confidence interval: 1.11, 1.30) jobs at baseline. These data suggest that unfavorable work characteristics may have a spillover effect on leisure-time physical activity. [ABSTRACT FROM AUTHOR]

Menstrual bleeding patterns are considered relevant indicators of reproductive health, though few studies have evaluated patterns among regularly menstruating premenopausal women. The authors evaluated self-reported bleeding patterns, incidence of spotting, and associations with reproductive hormones among 201 women in the BioCycle Study (2005–2007) with 2 consecutive cycles. Bleeding patterns were assessed by using daily questionnaires and pictograms. Marginal structural models were used to evaluate associations between endogenous hormone concentrations and subsequent total reported blood loss and bleeding length by weighted linear mixed-effects models and weighted parametric survival analysis models. Women bled for a median of 5 days (standard deviation: 1.5) during menstruation, with heavier bleeding during the first 3 days. Only 4.8% of women experienced midcycle bleeding. Increased levels of follicle-stimulating hormone (β = 0.20, 95% confidence interval: 0.13, 0.27) and progesterone (β = 0.06, 95% confidence interval: 0.03, 0.09) throughout the cycle were associated with heavier menstrual bleeding, and higher follicle-stimulating hormone levels were associated with longer menses. Bleeding duration and volume were reduced after anovulatory compared with ovulatory cycles (geometric mean blood loss: 29.6 vs. 47.2 mL; P = 0.07). Study findings suggest that detailed characterizations of bleeding patterns may provide more insight than previously thought as noninvasive markers for endocrine status in a given cycle. [ABSTRACT FROM PUBLISHER]

With the advent of Internet-based 24-hour recall (24HR) instruments, it is now possible to envision their use in cohort studies investigating the relation between nutrition and disease. Understanding that all dietary assessment instruments are subject to measurement errors and correcting for them under the assumption that the 24HR is unbiased for usual intake, here the authors simultaneously address precision, power, and sample size under the following 3 conditions: 1) 1–12 24HRs; 2) a single calibrated food frequency questionnaire (FFQ); and 3) a combination of 24HR and FFQ data. Using data from the Eating at America’s Table Study (1997–1998), the authors found that 4–6 administrations of the 24HR is optimal for most nutrients and food groups and that combined use of multiple 24HR and FFQ data sometimes provides data superior to use of either method alone, especially for foods that are not regularly consumed. For all food groups but the most rarely consumed, use of 2–4 recalls alone, with or without additional FFQ data, was superior to use of FFQ data alone. Thus, if self-administered automated 24HRs are to be used in cohort studies, 4–6 administrations of the 24HR should be considered along with administration of an FFQ. [ABSTRACT FROM PUBLISHER]

The authors aimed to describe how longitudinal patterns of physical activity during mid-adulthood (ages 31–53 years) can be characterized using latent class analysis in a population-based birth cohort study, the Medical Research Council’s 1946 National Survey of Health and Development. Three different types of physical activity—walking, cycling, and leisure-time physical activity—were analyzed separately using self-reported data collected from questionnaires between 1977 and 1999; 3,847 study members were included in the analysis for one or more types of activity. Patterns of activity differed by sex, so stratified analyses were conducted. Two walking latent classes were identified representing low (52.8% of males in the cohort, 33.5% of females) and high (47.2%, 66.5%) levels of activity. Similar low (91.4%, 82.1%) and high (8.6%, 17.9%) classes were found for cycling, while 3 classes were identified for leisure-time physical activity: “low activity” (46.2%, 48.2%), “sports and leisure activity” (31.0%, 35.3%), and “gardening and do-it-yourself activities” (22.8%, 16.5%). The classes were reasonably or very well separated, with the exception of walking in females. Latent class analysis was found to be a useful tool for characterizing longitudinal patterns of physical activity, even when the measurement instrument differs slightly across ages, which added value in comparison with observed activity at a single age. [ABSTRACT FROM PUBLISHER]

Prevalence of depression is associated inversely with some indicators of socioeconomic position, and the stress of social disadvantage is hypothesized to mediate this relation. Relative to whites, blacks have a higher burden of most physical health conditions but, unexpectedly, a lower burden of depression. This study evaluated an etiologic model that integrates mental and physical health to account for this counterintuitive patterning. The Baltimore Epidemiologic Catchment Area Study (Maryland, 1993–2004) was used to evaluate the interaction between stress and poor health behaviors (smoking, alcohol use, poor diet, and obesity) and risk of depression 12 years later for 341 blacks and 601 whites. At baseline, blacks engaged in more poor health behaviors and had a lower prevalence of depression compared with whites (5.9% vs. 9.2%). The interaction between health behaviors and stress was nonsignificant for whites (odds ratio (OR = 1.04, 95% confidence interval: 0.98, 1.11); for blacks, the interaction term was significant and negative (β: −0.18, P < 0.014). For blacks, the association between median stress and depression was stronger for those who engaged in zero (OR = 1.34) relative to 1 (OR = 1.12) and ≥2 (OR = 0.94) poor health behaviors. Findings are consistent with the proposed model of mental and physical health disparities. [ABSTRACT FROM PUBLISHER]

Parity, oral contraceptive use, and hysterectomy are known to protect against ovarian cancer, whereas the effect of other reproductive factors remains unclear. The authors investigated the association between several reproductive and hormonal factors and the risk of epithelial invasive ovarian cancer among postmenopausal women participating in the Netherlands Cohort Study on Diet and Cancer. Information on reproductive history and exogenous hormone use was obtained through a self-administered questionnaire at baseline in 1986. After 16.3 years of follow-up, 375 cases and 2,331 subcohort members were available for case-cohort analysis. Ovarian cancer risk was reduced for parous women, with increasing parity, and for hysterectomized women. Moreover, the authors found evidence that oral contraceptive use is protective against ovarian cancer, even when initiated at an older age. In addition, a reduced risk was observed for each year reduction in age at natural menopause and per year reduction in total menstrual life span. A small increased risk was observed with prolonged time to pregnancy, but no difference was found between ever-married nulliparous women and never-married nulliparous women. Moreover, no associations were observed for age at first birth, age at menarche, age at first and last use of oral contraceptives, and use of hormone replacement therapy. [ABSTRACT FROM PUBLISHER]

Weight gain during pregnancy may contribute to increased urinary incontinence (UI) during and after pregnancy, but scientific support is lacking. The effect of weight loss on UI postpartum is unclear. From 1999 to 2006, investigators in the Norwegian Mother and Child Cohort Study recruited pregnant women during pregnancy. This study was based on 12,679 primiparous women who were continent before pregnancy. Data were obtained from questionnaires answered at weeks 15 and 30 of pregnancy and 6 months postpartum. Weight gain greater than the 50th percentile during weeks 0–15 of pregnancy was weakly associated with higher incidence of UI at week 30 compared with weight gain less than or equal to the 50th percentile. Weight gain greater than the 50th percentile during pregnancy was not associated with increased prevalence of UI 6 months postpartum. For each kilogram of weight loss from delivery to 6 months postpartum among women who were incontinent during pregnancy, the relative risk for UI decreased 2.1% (relative risk = 0.98, 95% confidence interval: 0.97, 0.99). Weight gain during pregnancy does not seem to be a risk factor for increased incidence or prevalence of UI during pregnancy or postpartum. However, weight loss postpartum may be important for avoiding incontinence and regaining continence 6 months postpartum. [ABSTRACT FROM PUBLISHER]

Variability of angina symptoms over a 5-year period was examined in a prospective study, in which 7,109 British middle-aged men completed two chest pain questionnaires, Q1 (1978-1980) and Q5 (1983-1985), and were classified as having no chest pain, nonexertional chest pain, or angina (Q) (exertional chest pain) on each occasion. Within persons, there was considerable variability in response to the chest pain questions at Q1 and Q5. Angina (Q) persistence showed marked associations with previous myocardial infarction, diagnosed angina, electrocardiogram ischemia, and subsequent major ischemic heart disease events from Q5 onward. Compared with men without angina (Q), the age-adjusted hazard ratios were 1.5 (95% confidence interval (CI): 1.1, 2.2) for angina (Q) at Q1 only, 2.6 (95% CI: 2.1, 3.2) for angina (Q) at Q5 only, and 3.4 (95% CI: 2.8, 4.3) for angina (Q) on both occasions. For men without diagnosed ischemic heart disease, for whom apparent remission of angina (Q) was particularly frequent, a similar pattern of association was found between angina (Q) persistence and subsequent major events. In middle-aged men, exertional chest pain is a strong indicator of major coronary risk but frequently appears transient in the longer term. Persistently reported symptoms are associated with severe disease and a poor prognosis. Am J Epidemiol 2001;153:1173-82. [ABSTRACT FROM AUTHOR]

To investigate whether greater intakes of calcium, vitamin D, or milk products may protect against ischemic heart disease mortality, the authors analyzed data from a prospective cohort study of 34,486 postmenopausal lowa women 55–69 years old and without a history of ischemic heart disease who completed a dietary questionnaire in 1986. Through 1994, 387 deaths due to ischemic heart disease were documented (International Classification of Diseases, Ninth Revision, codes 410–414, 429.2). The multivariate-adjusted relative risks for the highest versus the lowest quartiles of total calcium, vitamin D, and milk product intakes were as follows: 0.67 (95% confidence interval (CI) 0.47–0.94; p for trend = 0.09) for calcium, 1.41 (95% CI 0.93–2.15; p for trend = 0.12) for vitamin D, and 0.94 (95% CI 0.66–1.35; p for trend = 0.68) for milk products. The relative risk was 0.63 (95% CI 0.40–0.98) for high dietary calcium but no supplemental calcium intake and 0.66 (95% CI 0.36–1.23) for high supplemental calcium but low dietary calcium intake. These results suggest that a higher intake of calcium, but not of vitamin D or milk products, is associated with reduced ischemic heart disease mortality in postmenopausal women, and reduced risk may be achievable whether the higher intake of calcium is attained by diet, supplements, or both. Am J Epidemiol 1999;149:151–61. [ABSTRACT FROM AUTHOR]

The association between dietary acrylamide intake and the incidence of invasive breast cancer was examined among 61,433 Swedish women who were cancer free and completed a food frequency questionnaire in 1987–1990 and again in 1997. During a mean follow-up of 17.4 years, a total of 2,952 incident cases of breast cancer were diagnosed in the cohort. In multivariate analyses controlling for breast cancer risk factors, no statistically significant association was observed between long-term acrylamide intake (assessed at baseline and in 1997) and the risk of breast cancer, overall or by estrogen receptor (ER) and progesterone receptor (PR) status. The multivariate rate ratios comparing extreme quartiles of acrylamide intake were 0.91 (95% confidence interval (CI): 0.80, 1.02) for overall breast cancer, 0.89 (95% CI: 0.74, 1.08) for ER+PR+ tumors, 1.17 (95% CI: 0.84, 1.64) for ER+PR– tumors, and 0.91 (95% CI: 0.61, 1.38) for ER–PR– tumors. The association between acrylamide intake and breast cancer risk did not differ by smoking status. These findings for Swedish women do not support the hypothesis that dietary acrylamide is positively associated with risk of breast cancer, at least not within the ranges of acrylamide consumed by this population. [ABSTRACT FROM AUTHOR]