An Investigation of Selection Bias in Estimating Racial Disparity in Stroke Risk FactorsThe REGARDS Study
AbstractSelection due to survival or attrition might bias estimates of racial disparities in health, but few studies quantify the likely magnitude of such bias. In a large national cohort with moderate loss to follow-up, we contrasted racial differences in 2 stroke risk factors, incident hypertension and incident left ventricular hypertrophy, estimated by complete-case analyses, inverse probability of attrition weighting, and the survivor average causal effect. We used data on 12,497 black and 17,660 white participants enrolled in the United States (2003 –2007) and collected incident risk factor data approximately 10...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Associations Between Features of Placental Morphology and Birth Weight in Dichorionic Twins
AbstractLow birth weight is associated with perinatal and long-term morbidity and mortality, and may be a result of abnormal placental development and function. In studies of singletons, associations have been reported between features of placental morphology and birth weight. Evaluating similar associations within twin pairs offers a unique opportunity to control for key confounders shared within a twin pair, including gestational age, parental characteristics, and intrauterine environment. Data from 3 studies in the United States that were completed from 2012 to 2013, 2006 to 2008, and 1959 to 1966 were used in our analy...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Some desirable properties of the bonferroni correction: is the bonferroni correction really so bad?
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Shift Work and Respiratory Infections in Health-Care Workers
In conclusion, shift workers in health care had more ILI/ARI episodes and more severe ILI/ARI episodes than non–shift workers, but with a similar duration. Insight into underlying mechanisms connecting shift work and in fection susceptibility will contribute to the design of preventive initiatives. (Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Guideline-Based Physical Activity and Survival Among US Men With Nonmetastatic Prostate Cancer
AbstractThe survival impact of adhering to current physical activity guidelines after prostate cancer diagnosis is unknown. We therefore emulated a target trial of guideline-based physical activity interventions and 10-year survival among US men with nonmetastatic prostate cancer. We used observational data on 2,299 men in the Health Professionals Follow-up Study who were diagnosed with nonmetastatic prostate cancer from 1998 to 2010 and were free of conditions that might have precluded participation at baseline (first postdiagnostic questionnaire). We estimated their survival under several guideline-based physical activit...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Multinomial Extension of Propensity Score Trimming Methods: A Simulation Study
In conclusion, our proposed definitions of multinomial PS trimming methods were beneficial wi thin our simulation settings that focused on the influence of unmeasured confounders. (Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Gestational Age at Arrest of Development: An Alternative Approach for Assigning Time at Risk in Studies of Time-Varying Exposures and Miscarriage
AbstractThe time between arrest of pregnancy development and miscarriage represents a window in which the pregnancy is nonviable and not developing. In effect, the pregnancy loss has already occurred, and additional exposure cannot influence its outcome. However, epidemiologic studies of miscarriage traditionally use gestational age at miscarriage (GAM) to assign time in survival analyses, which overestimates duration of exposure and time at risk. In Right From the Start, a pregnancy cohort study (2000 –2012), we characterized the gap between estimated gestational age at arrest of development (GAAD) and miscarriage u...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Mortality and Cancer Incidence in Carriers of Balanced Robertsonian Translocations: A National Cohort Study
AbstractA balanced robertsonian translocation (rob) results from fusion of 2 acrocentric chromosomes. Carriers are phenotypically normal and are often diagnosed because of recurrent miscarriages, infertility, or aneuploid offspring. Mortality and site-specific cancer risks in carriers have not been prospectively investigated. We followed 1,987 carriers diagnosed in Great Britain for deaths and cancer risk, over an average of 24.1 years. Standardized mortality and incidence ratios were calculated comparing the number of observed events against population rates. Overall mortality was higher for carriers diagnosed before age ...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Evaluation of the Performance of Algorithms That Use Serial Hepatitis C RNA Tests to Predict Treatment Initiation and Sustained Virological Response Among Patients Infected With Hepatitis C Virus
AbstractThe structure of electronic medical record data prevents easy population-level monitoring of hepatitis C virus (HCV) treatment uptake and cure. Using an HCV registry from a public hospital system in Atlanta, Georgia, we developed multiple algorithms that use serial HCV RNA test results as proxy measures for initiation of direct-acting antiviral (DAA) treatment and sustained virological response (SVR). We calculated sensitivity and positive predictive values (PPVs) by comparing the algorithms with the DAA initiation and SVR results from the registry. From December 2013 to August 2016, 1,807 persons actively infected...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Causal Mediation Analysis With Observational Data: Considerations and Illustration Examining Mechanisms Linking Neighborhood Poverty to Adolescent Substance Use
AbstractUnderstanding the mediation mechanisms by which an exposure or intervention affects an outcome can provide a look into what has been called a “black box” of many epidemiologic associations, thereby providing further evidence of a relationship and possible points of intervention. Rapid methodologic developments in mediation analyses mean that there are a growing number of approaches for researchers to consider, each with its own set of assumptions, advantages, and disadvantages. This has understandably resulted in some confusion among applied researchers. Here, we provide a brief overview of the mediatio...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Stress Disorders and Dementia in the Danish Population
This study included Danes aged 40 years or older with a stress disorder diagnosis (n = 47,047) and a matched comparison cohort (n = 232,141) without a stress disorder diagnosis with data from 1995 through 2011. Diagnoses were culled from national registries. We used Cox proportional hazards regression to estimate associations between stress disorders and dementia. Risk of dementia was higher for persons with stress disorders than for persons without such diagnosis; adjusted hazard ratios ranged from 1.6 to 2.8. There was evidence of an interaction between sex and stress disorders in predicting dementia, with a higher rate ...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Structure and Control of Healthy Worker Effects in Studies of Pregnancy Outcomes
AbstractMuch of the literature on the healthy worker effect focuses on studies of chronic disease and mortality; however, when studying pregnancy outcomes, these effects might differ because of the short, defined risk periods of most pregnancy outcomes. Three pregnancy-specific healthy worker effects have also been described, but the structure of these effects has not yet been investigated when occupational exposure, and not employment status, is the exposure of interest. We used directed acyclic graphs to examine healthy worker effects in studies of occupational exposures and pregnancy outcomes: the healthy hire effect, t...
Source: American Journal of Epidemiology - August 23, 2019 Category: Epidemiology Source Type: research

Comparison of the Associations of Early-Life Factors on Wheezing Phenotypes in Preterm-Born Children and Term-Born Children
AbstractAlthough respiratory symptoms, including wheezing, are common in preterm-born subjects, the natural history of the wheezing phenotypes and the influence of early-life factors and characteristics on phenotypes are unclear. Participants from the Millennium Cohort Study who were born between 2000 and 2002 were studied at 9 months and at 3, 5, 7, and 11 years. We used data-driven methods to define wheezing phenotypes in preterm-born children and investigated whether the association of early-life factors and characteristics with wheezing phenotypes was similar between preterm- and term-born children. A total of 1,049/1,...
Source: American Journal of Epidemiology - January 22, 2019 Category: Epidemiology Source Type: research

Potential Effects on Mortality of Replacing Sedentary Time With Short Sedentary Bouts or Physical Activity: A National Cohort Study
AbstractLittle is known concerning the type of activity that should be substituted for sedentary time and its potentially most hazardous form (prolonged sedentary bouts) to impart health benefit. We used isotemporal substitution techniques to examine whether 1) replacing total sedentary time with light-intensity or moderate to vigorous physical activity (LIPA or MVPA) or 2) replacing prolonged sedentary bouts with shorter sedentary bouts is associated with reductions in all-cause mortality risk. Participants (n = 7,999) from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a national cohort of U...
Source: American Journal of Epidemiology - January 14, 2019 Category: Epidemiology Source Type: research

The Impact of Screening and Partner Notification on Chlamydia Prevalence and Numbers of Infections Averted in the United States, 2000 –2015: Evaluation of Epidemiologic Trends Using a Pair-Formation Transmission Model
In this study, we calibrated a novel sex- and age-stratified pair-formation transmission model of chlamydial infection to epidemiologic data in the United States for 2000 –2015. We used sex- and age-specific prevalence estimates from the National Health and Nutrition Examination Surveys, case report data from national chlamydia surveillance, and survey data from the Youth Risk Behavior Survey on the proportion of the sexually active population aged 15–18 years. W e were able to reconcile national prevalence estimates and case report data by allowing for changes over time in screening coverage and reporting comp...
Source: American Journal of Epidemiology - January 4, 2019 Category: Epidemiology Source Type: research

Re: “design strategy of the sabes study: diagnosis and treatment of early hiv infection among men who have sex with men and transgender women in lima, peru, 2013–2017”
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - August 1, 2018 Category: Epidemiology Source Type: research

Retirements of Coal and Oil Power Plants in California: Association With Reduced Preterm Birth Among Populations Nearby
AbstractCoal and oil power plant retirements reduce air pollution nearby, but few studies have leveraged these natural experiments for public health research. We used California Department of Public Health birth records and US Energy Information Administration data from 2001 –2011 to evaluate the relationship between the retirements of 8 coal and oil power plants and nearby preterm (gestational age of
Source: American Journal of Epidemiology - May 16, 2018 Category: Epidemiology Source Type: research

Invited Commentary: The Power of Preterm Birth to Motivate a Cleaner Environment
AbstractThis commentary reflects on a natural experiment reported by Casey et al. (Am J Epidemiol. 2018;187(8):1586 –1594) that tested the association between living near a coal or oil power plant and preterm birth. They found that retiring power plants resulted in a significant reduction in preterm birth, with larger effects observed for late preterm birth and among non-Hispanic black mothers and infants. Natu ral experiments, in particular the Utah Valley Steel Mill closure, have played a prominent role in the evidence base for air pollution regulation due to their demonstrated impact on cardiopulmonary effects in ...
Source: American Journal of Epidemiology - May 16, 2018 Category: Epidemiology Source Type: research

Educational Mobility Across Generations and Depressive Symptoms Over 10 Years Among US Latinos
AbstractFew studies have collected intergenerational data to assess the association between educational mobility across multiple generations and offspring depression. Using data from the Sacramento Area Latino Study on Aging (1998 –2008), we assessed the influence of intergenerational education on depressive symptoms over 10 years among 1,786 Latino individuals (mean age = 70.6 years). Educational mobility was classified as stable-low (low parental/low offspring education), upwardly mobile (low parental/high offspring educa tion), stable-high (high parental/high offspring education), or downwardly mobile (high parent...
Source: American Journal of Epidemiology - May 14, 2018 Category: Epidemiology Source Type: research

An Epigenome-Wide Association Study of Obesity-Related Traits
AbstractWe conducted an epigenome-wide association study on obesity-related traits. We used data from 2 prospective, population-based cohort studies: the Rotterdam Study (RS) (2006 –2013) and the Atherosclerosis Risk in Communities (ARIC) Study (1990–1992). We used the RS (n = 1,450) as the discovery panel and the ARIC Study (n = 2,097) as the replication panel. Linear mixed-effect models were used to assess the cross-sectional associations between genome-wide DNA methylation in leukocytes and body mass index (BMI) and waist circumference (WC), adjusting for sex, age, smoking, leukocyte proportions, array numbe...
Source: American Journal of Epidemiology - May 14, 2018 Category: Epidemiology Source Type: research

Residential Racial Isolation and Spatial Patterning of Type 2 Diabetes Mellitus in Durham, North Carolina
AbstractNeighborhood characteristics such as racial segregation may be associated with type 2 diabetes mellitus, but studies have not examined these relationships using spatial models appropriate for geographically patterned health outcomes. We constructed a local, spatial index of racial isolation (RI) for black residents in a defined area, measuring the extent to which they are exposed only to one another, to estimate associations of diabetes with RI and examine how RI relates to spatial patterning in diabetes. We obtained electronic health records from 2007 –2011 from the Duke Medicine Enterprise Data Warehouse. P...
Source: American Journal of Epidemiology - May 14, 2018 Category: Epidemiology Source Type: research

Does Socioeconomic Status Modify the Association Between Preterm Birth and Children ’s Early Cognitive Ability and Kindergarten Academic Achievement in the United States?
AbstractBeing born preterm and being raised in poverty are each linked with adverse cognitive outcomes. Using data from 5,250 singletons born in the United States in 2001 and enrolled in the Early Childhood Longitudinal Study, Birth Cohort, we examined whether household socioeconomic status (SES) modified the association between preterm birth (PTB) and children ’s scores on cognitive assessments at age 2 years and reading and mathematics assessments at kindergarten age. Gestational age was measured from birth certificates and categorized as early preterm, moderate preterm, late preterm, early term, and term. SES was ...
Source: American Journal of Epidemiology - May 11, 2018 Category: Epidemiology Source Type: research

Longitudinal Patterns of Physical Activity Among Older Adults: A Latent Transition Analysis
AbstractMost epidemiologic studies of physical activity measure either total energy expenditure or engagement in a single type of activity, such as walking. These approaches may gloss over important nuances in activity patterns. We performed a latent transition analysis to identify patterns of activity, as well as neighborhood and individual determinants of changes in those activity patterns, over 2 years in a cohort of 2,023 older adult residents of New York, New York, surveyed between 2011 and 2013. We identified 7 latent classes: 1) mostly inactive, 2) walking, 3) exercise, 4) household activities and walking, 5) househ...
Source: American Journal of Epidemiology - May 11, 2018 Category: Epidemiology Source Type: research

Four authors reply
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - May 4, 2018 Category: Epidemiology Source Type: research

Re: “a decade of war: prospective trajectories of posttraumatic stress disorder symptoms among deployed us military personnel and the influence of combat exposure”
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - May 4, 2018 Category: Epidemiology Source Type: research

Re: “modeling risk-factor trajectories when measurement tools change sequentially during follow-up in cohort studies: application to dietary habits in prodromal dementia”
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - May 1, 2018 Category: Epidemiology Source Type: research

Prenatal Exposure to Acetaminophen and Risk for Attention Deficit Hyperactivity Disorder and Autistic Spectrum Disorder: A Systematic Review, Meta-Analysis, and Meta-Regression Analysis of Cohort Studies
AbstractAcetaminophen is the analgesic and antipyretic most commonly used during pregnancy. Evidence of neurodisruptive properties is accumulating. Therefore, we sought to evaluate the risk for attention deficit hyperactivity disorder (ADHD) and autistic spectrum disorder (ASD) in the offspring of women exposed to acetaminophen during pregnancy. We searched MEDLINE, Embase, and Cochrane databases for relevant studies up to January 2017. Data were independently extracted and assessed by 2 researchers. Seven eligible retrospective cohorts included 132,738 mother-child pairs, with follow-up periods ranging from 3 to 11 years....
Source: American Journal of Epidemiology - April 24, 2018 Category: Epidemiology Source Type: research

Development, Construct Validity, and Predictive Validity of a Continuous Frailty Scale: Results From 2 Large US Cohorts
We examined the association of the continuous frailty scale with mortality and disability. The unidimensional model fit the data satisfactorily; similar factor structure was observed across 2 cohorts. Gait speed and weight loss were the strongest and weakest indicators, respectively; grip strength, exhaustion, and physical activity had similar strength in measuring frailty. In each cohort, the continuous frailty scale was strongly associated with mortality and disability and continued to be associated with outcomes among robust and prefrail persons classified by the FP scale. (Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - April 24, 2018 Category: Epidemiology Source Type: research

Multilevel Regression and Poststratification: A Modeling Approach to Estimating Population Quantities From Highly Selected Survey Samples
AbstractInvestigators in large-scale population health studies face increasing difficulties in recruiting representative samples of participants. Nonparticipation, item nonresponse, and attrition, when follow-up is involved, often result in highly selected samples even in well-designed studies. We aimed to assess the potential value of multilevel regression and poststratification, a method previously used to successfully forecast US presidential election results, for addressing biases due to nonparticipation in the estimation of population descriptive quantities in large cohort studies. The investigation was performed as a...
Source: American Journal of Epidemiology - April 9, 2018 Category: Epidemiology Source Type: research

Breastfeeding and Childhood Wheeze: Age-Specific Analyses and Longitudinal Wheezing Phenotypes as Complementary Approaches to the Analysis of Cohort Data
AbstractSystematic reviews suggest that breastfeeding is associated with a lower risk of asthma, although marked heterogeneity exists. Using UK Millennium Cohort Study data (n = 10,126 children, born 2000 –2002), we examined the association between breastfeeding duration and wheezing in the previous year, first for each age group separately (ages 9 months, 3 years, 5 years, 7 years, and 11 years) and then in terms of a longitudinal wheezing phenotype: “early transient” (wheezing any time up to age 5 years but not thereafter), “late onset” (any time from age 7 years but not beforehand), and &ld...
Source: American Journal of Epidemiology - April 3, 2018 Category: Epidemiology Source Type: research

2017 Articles of the Year, Reviewers of the Year, and Figure of the Year
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - April 1, 2018 Category: Epidemiology Source Type: research

RE: “Deployment And Preterm Birth Among US Army Soldiers”
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - April 1, 2018 Category: Epidemiology Source Type: research

Population Density in Hiroshima and Nagasaki Before the Bombings in 1945: Its Measurement and Impact on Radiation Risk Estimates in the Life Span Study of Atomic Bomb Survivors
AbstractIn the Life Span Study cohort of atomic bomb survivors, differences in urbanicity between high-dose and low-dose survivors could confound the association between radiation dose and adverse outcomes. We obtained data on the population distribution in Hiroshima and Nagasaki before the 1945 bombings and quantified the impact of adjustment for population density on radiation risk estimates for mortality (1950 –2003) and incident solid cancer (1958–2009). Population density ranged from 4,671 to 14,378 people/km2 in the urban region of Hiroshima and 5,748 to 19,149 people/km2 in the urban region of Nagasaki. ...
Source: American Journal of Epidemiology - March 29, 2018 Category: Epidemiology Source Type: research

A Randomized Controlled Trial to Measure Spillover Effects of a Combined Water, Sanitation, and Handwashing Intervention in Rural Bangladesh
AbstractWater, sanitation, and handwashing interventions may confer spillover effects on intervention recipients ’ neighbors by interrupting pathogen transmission. We measured geographically local spillovers in the Water Quality, Sanitation, and Handwashing (WASH) Benefits Study, a cluster-randomized trial in rural Bangladesh, by comparing outcomes among neighbors of intervention versus those of control part icipants. Geographically defined clusters were randomly allocated to a compound-level intervention (i.e., chlorinated drinking water, upgraded sanitation, and handwashing promotion) or control arm. From January 2...
Source: American Journal of Epidemiology - March 27, 2018 Category: Epidemiology Source Type: research

Amyotrophic Lateral Sclerosis and Exposure to Diesel Exhaust in a Danish Cohort
In this study, we investigated the association between occupational exposure to DE and odds of ALS. ALS cases were identified from the Danish National Patient Registry (1982 –2013) and individually matched to 100 controls per case on the basis of birth year and sex. Using information on occupational history from 1964 onward obtained from the Danish Pension Fund, we estimated cumulative DE exposures using a job exposure matrix. We evaluated associations using condition al logistic regression analyses and stratified the analyses by sex. Using a 10-year lag period, DE exposure was positively associated with ALS among me...
Source: American Journal of Epidemiology - March 24, 2018 Category: Epidemiology Source Type: research

Dietary Protein and Preservation of Physical Functioning Among Middle-Aged and Older Adults in the Framingham Offspring Study
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.
Source: American Journal of Epidemiology - March 24, 2018 Category: Epidemiology Source Type: research

Antiretroviral Therapy and Mortality in Rural South Africa: A Comparison of Causal Modeling Approaches
AbstractEstimation of causal effects from observational data is a primary goal of epidemiology. The use of multiple methods with different assumptions relating to exchangeability improves causal inference by demonstrating robustness across assumptions. We estimated the effect of antiretroviral therapy (ART) on mortality in rural KwaZulu-Natal, South Africa, from 2007 to 2011, using 2 methods with substantially different assumptions: the regression discontinuity design (RDD) and inverse-probability –weighted (IPW) marginal structural models (MSMs). The RDD analysis took advantage of a CD4-cell-count–based thresh...
Source: American Journal of Epidemiology - March 23, 2018 Category: Epidemiology Source Type: research

Landmark Models for Optimizing the Use of Repeated Measurements of Risk Factors in Electronic Health Records to Predict Future Disease Risk
AbstractThe benefits of using electronic health records (EHRs) for disease risk screening and personalized health-care decisions are being increasingly recognized. Here we present a computationally feasible statistical approach with which to address the methodological challenges involved in utilizing historical repeat measures of multiple risk factors recorded in EHRs to systematically identify patients at high risk of future disease. The approach is principally based on a 2-stage dynamic landmark model. The first stage estimates current risk factor values from all available historical repeat risk factor measurements via l...
Source: American Journal of Epidemiology - March 23, 2018 Category: Epidemiology Source Type: research

Relative Performance of Propensity Score Matching Strategies for Subgroup Analyses
AbstractPostapproval drug safety studies often use propensity scores (PSs) to adjust for a large number of baseline confounders. These studies may involve examining whether treatment safety varies across subgroups. There are many ways a PS could be used to adjust for confounding in subgroup analyses. These methods have trade-offs that are not well understood. We conducted a plasmode simulation to compare relative performance of 5 methods involving PS matching for subgroup analysis, including methods frequently used in applied literature whose performance has not been previously directly compared. These methods varied as to...
Source: American Journal of Epidemiology - March 15, 2018 Category: Epidemiology Source Type: research

Prognostic Association of Major Frailty Domain Trajectories With 5-Year Mortality in Very Old Adults: Results From the PARTAGE Cohort Study
AbstractWe aimed to identify trajectories of nutrition, cognitive function, and autonomy over time among very old adults and to assess their impact on mortality. A cohort of subjects aged ≥80 years (in 2007–2008) who were followed for 5 years in 72 Italian and French nursing homes was used for post hoc analyses. Body mass index (BMI; weight (kg)/height (m)2), Mini-Mental State Examination (MMSE) score, and Katz Index of Independence in Activities of Daily Living (ADL) score were assessed at 4 time points. Information on vital status was collected during follow-up. Latent trajectory and Cox models were used. In the...
Source: American Journal of Epidemiology - March 15, 2018 Category: Epidemiology Source Type: research

The Association of Arsenic Exposure and Arsenic Metabolism With the Metabolic Syndrome and Its Individual Components: Prospective Evidence From the Strong Heart Family Study
AbstractInorganic arsenic exposure is ubiquitous, and both exposure and interindividual differences in its metabolism have been associated with cardiometabolic risk. However, the associations of arsenic exposure and arsenic metabolism with the metabolic syndrome (MetS) and its individual components are relatively unknown. We used Poisson regression with robust variance to evaluate the associations of baseline arsenic exposure (urinary arsenic levels) and metabolism (relative percentage of arsenic species over their sum) with incident MetS and its individual components (elevated waist circumference, elevated triglycerides, ...
Source: American Journal of Epidemiology - March 15, 2018 Category: Epidemiology Source Type: research

Associations Between Maternal Obesity and Pregnancy Hyperglycemia and Timing of Puberty Onset in Adolescent Girls: A Population-Based Study
AbstractEarly puberty is associated with adverse health outcomes. We investigated whether in utero exposure to maternal obesity is associated with daughters ’ pubertal timing using 15,267 racially/ethnically diverse Kaiser Permanente Northern California members aged 6–11 years with pediatrician-assessed Tanner staging (2003–2017). We calculated maternal body mass index (BMI; weight (kg)/height (m)2) during pregnancy from the electronic health record data. Using a proportional hazards model with interval censoring, we examined the associations between maternal obesity and girls ’ pubertal timing, as ...
Source: American Journal of Epidemiology - March 15, 2018 Category: Epidemiology Source Type: research

Associations Between the Built Environment and Objective Measures of SleepThe Multi-Ethnic Study of Atherosclerosis
AbstractAlthough dense neighborhood built environments support increased physical activity and lower obesity, these features may also disturb sleep. Therefore, we sought to understand the association between the built environment and objectively measured sleep. From 2010 to 2013, we analyzed data from examination 5 of the Multi-Ethnic Study of Atherosclerosis, a diverse population from 6 US cities. We fit multilevel models that assessed the association between the built environment (Street Smart Walk Score, social engagement destinations, street intersections, and population density) and sleep duration or efficiency from 1...
Source: American Journal of Epidemiology - March 14, 2018 Category: Epidemiology Source Type: research

The authors reply
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - March 14, 2018 Category: Epidemiology Source Type: research

Re: “prospective cohort study of uterine fibroids and miscarriage risk”
(Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - March 14, 2018 Category: Epidemiology Source Type: research

Timing of Birth as an Emergent Risk Factor for Rotavirus Hospitalization and Vaccine Performance in the Postvaccination Era in the United States
AbstractRotavirus vaccines were introduced in the United States in 2006, and in the years since they have fundamentally altered the seasonality of rotavirus infection and have shifted disease outbreaks from annual epidemics to biennial epidemics. We investigated whether season and year of birth have emerged as risk factors for rotavirus or have affected vaccine performance. We constructed a retrospective birth cohort of US children under age 5 years using the 2001 –2014 MarketScan database (Truven Health Analytics, Chicago, Illinois). We evaluated the associations of season of birth, even/odd year of birth, and inter...
Source: American Journal of Epidemiology - March 13, 2018 Category: Epidemiology Source Type: research

Longitudinal Associations Between Respiratory Infections and Asthma in Young Children
We examined temporal dependencies between repeated assessments of respiratory tract infections (RTIs) and asthma in children in the Leicester Respiratory Cohort, Leicestershire, United Kingdom. Information associated with asthma (i.e., doctor diagnosis, health care visits, wheeze frequency) and RTIs (i.e., cold duration and frequency, cough with colds, ear infections) in the previous 12 months was assessed repeatedly at ages 1, 4, and 6 years for children born between April 1996 and April 1997. We determined associations between contemporaneous and lagged measures of asthma and RTIs, using structural equation modelling. In...
Source: American Journal of Epidemiology - March 13, 2018 Category: Epidemiology Source Type: research

Applying Multiple Statistical Methods to Derive an Index of Dietary Behaviors Most Related to Obesity
AbstractTo evaluate the success of dietary interventions, we need measures that are more easily assessed and that closely align with intervention messaging. An index of obesogenic dietary behaviors (e.g., consumption of fast food and soft drinks, low fruit and vegetable consumption, and task eating (eating while engaging in other activities)) may serve this purpose and could be derived via data-driven methods typically used to describe nutrient intake. We used behavioral and physical measurement (i.e., body mass index, waist circumference) data from a subset of 2 independent cross-sectional samples of employees enrolled in...
Source: American Journal of Epidemiology - March 12, 2018 Category: Epidemiology Source Type: research

A Note on G-Estimation of Causal Risk Ratios
AbstractG-estimation is a flexible, semiparametric approach for estimating exposure effects in epidemiologic studies. It has several underappreciated advantages over other propensity score –based methods popular in epidemiology, which we review in this article. However, it is rarely used in practice, due to a lack of off-the-shelf software. To rectify this, we show a simple trick for obtaining G-estimators of causal risk ratios using existing generalized estimating equations softwar e. We extend the procedure to more complex settings with time-varying confounders. (Source: American Journal of Epidemiology)
Source: American Journal of Epidemiology - March 12, 2018 Category: Epidemiology Source Type: research

Preterm Birth and Small Size for Gestational Age in Singleton, In Vitro Fertilization Births Using Donor Oocytes
AbstractWe used 2006 –2015 US National Assisted Reproductive Technology Surveillance System data to compare preterm birth and fetal growth for liveborn singletons (24–42 weeks’ gestation) following in vitro fertilization with donor versus autologous oocytes. Using binary and multinomial logistic regression, we com puted adjusted odds ratios and 95% confidence intervals for associations between use of donor oocytes and preterm delivery, being small for gestational age (SGA), and being large for gestational age (LGA), stratified by fresh and thawed embryo status and accounting for maternal characteristics a...
Source: American Journal of Epidemiology - March 9, 2018 Category: Epidemiology Source Type: research