Associations of Food Insecurity and Memory Function Among Middle to Older-Aged Adults in the Health and Retirement Study.

Importance: Food insecurity is a leading public health issue in the US. Research on food insecurity and cognitive aging is scarce, and is mostly cross-sectional. Food insecurity status and cognition both can change over the life course, but their longitudinal relationship remains unexplored. Objective: To examine the longitudinal association between food insecurity and changes in memory function during a period of 18 years among middle to older-aged adults in the US. Design, Setting, and Participants: The Health and Retirement Study is an ongoing population-based cohort study of individuals aged 50 years or older. Participants with nonmissing information on their food insecurity in 1998 who contributed information on memory function at least once over the study period (1998-2016) were included. To account for time-varying confounding and censoring, marginal structural models were created, using inverse probability weighting. Data analyses were conducted between May 9 and November 30, 2022. Main outcomes and Measures: In each biennial interview, food insecurity status (yes/no) was assessed by asking respondents whether they had enough money to buy food or ate less than they felt they should. Memory function was a composite score based on self-completed immediate and delayed word recall task of a 10-word list and proxy-assessed validated instruments. Results: The analytic sample included 12 609 respondents (mean [SD] age, 67.7 [11.0] years, 8146 [64.60%] women, 10 277 [81.51%] non-Hispanic White), including 11 951 food-secure and 658 food-insecure individuals in 1998. Over time, the memory function of the food-secure respondents decreased by 0.045 SD units annually (ß for time, -0.045; 95% CI, -0.046 to -0.045 SD units). The memory decline rate was faster among food-insecure respondents than food-secure respondents, although the magnitude of the coefficient was small (ß for food insecurity × time, -0.0030; 95% CI, -0.0062 to -0.00018 SD units), which translates to an estimated 0.67 additional (ie, excess) years of memory aging over a 10-year period for food-insecure respondents compared with food-secure respondents. Conclusions and Relevance: In this cohort study of middle to older-aged individuals, food insecurity was associated with slightly faster memory decline, suggesting possible long-term negative cognitive function outcomes associated with exposure to food insecurity in older age.

Propensity Scores in Health Disparities Research: The Example of Cognitive Aging and the Hispanic Paradox.

BACKGROUND: Individuals of Mexican ancestry in the United States experience substantial socioeconomic disadvantages compared with non-Hispanic white individuals; however, some studies show these groups have similar dementia risk. Evaluating whether migration selection factors (e.g., education) associated with risk of Alzheimer disease and related dementia (ADRD) explain this paradoxical finding presents statistical challenges. Intercorrelation of risk factors, common with social determinants, could make certain covariate patterns very likely or unlikely to occur for particular groups, which complicates their comparison. Propensity score (PS) methods could be leveraged here to diagnose nonoverlap and help balance exposure groups. METHODS: We compare conventional and PS-based methods to examine differences in cognitive trajectories between foreign-born Mexican American, US-born Mexican American, and US-born non-Hispanic white individuals in the Health and Retirement Study (1994-2018). We examined cognition using a global measure. We estimated trajectories of cognitive decline from linear mixed models adjusted for migration selection factors also associated with ADRD risk conventionally or with inverse probability weighting. We also employed PS trimming and match weighting. RESULTS: In the full sample, where PS overlap was poor, unadjusted analyses showed both Mexican ancestry groups had worse baseline cognitive scores but similar or slower rates of decline compared with non-Hispanic white adults; adjusted findings were similar, regardless of method. Focusing analyses on populations where PS overlap was improved (PS trimming and match weighting) did not alter conclusions. CONCLUSIONS: Attempting to equalize groups on migration selection and ADRD risk factors did not explain paradoxical findings for Mexican ancestry groups in our study.

Practical Guide to Honest Causal Forests for Identifying Heterogeneous Treatment Effects.

"Heterogeneous treatment effects" is a term which refers to conditional average treatment effects (i.e., CATEs) that vary across population subgroups. Epidemiologists are often interested in estimating such effects because they can help detect populations that may particularly benefit from or be harmed by a treatment. However, standard regression approaches for estimating heterogeneous effects are limited by preexisting hypotheses, test a single effect modifier at a time, and are subject to the multiple-comparisons problem. In this article, we aim to offer a practical guide to honest causal forests, an ensemble tree-based learning method which can discover as well as estimate heterogeneous treatment effects using a data-driven approach. We discuss the fundamentals of tree-based methods, describe how honest causal forests can identify and estimate heterogeneous effects, and demonstrate an implementation of this method using simulated data. Our implementation highlights the steps required to simulate data sets, build honest causal forests, and assess model performance across a variety of simulation scenarios. Overall, this paper is intended for epidemiologists and other population health researchers who lack an extensive background in machine learning yet are interested in utilizing an emerging method for identifying and estimating heterogeneous treatment effects.

History of Low Hourly Wage and All-Cause Mortality Among Middle-aged Workers.

Importance: Earning a low wage is an increasingly recognized public health concern, yet little research exists on the long-term health consequences of sustained low-wage earning. Objective: To examine the association of sustained low-wage earning and mortality in a sample of workers with hourly wage reported biennially during peak midlife earning years. Design, Setting, and Participants: This longitudinal study included 4002 US participants, aged 50 years or older, from 2 subcohorts of the Health and Retirement Study (1992-2018) who worked for pay and reported earning hourly wages at 3 or more time points during a 12-year period during their midlife (1992-2004 or 1998-2010). Outcome follow-up occurred from the end of the respective exposure periods until 2018. Exposures: Low-wage-less than the hourly wage for full-time, full-year work at the federal poverty line-earning history was categorized as never earning a low wage, intermittently earning a low wage, and sustained earning a low wage. Main Outcomes and Measures: Cox proportional hazards and additive hazards regression models sequentially adjusted for sociodemographics, and economic and health covariates were used to estimate associations between low-wage history and all-cause mortality. We examined interaction with sex or employment stability on multiplicative and additive scales. Results: Of the 4002 workers (aged 50-57 years at the beginning of exposure period and 61-69 years at the end), 1854 (46.3%) were female; 718 (17.9%) experienced employment instability; 366 (9.1%) had a history of sustained low-wage earning; 1288 (32.2%) had intermittent low-wage earning periods; and 2348 (58.7%) had never earned a low wage. In unadjusted analyses, those who had never earned low wages experienced 199 deaths per 10 000 person-years, those with intermittent low wages, 208 deaths per 10 000 person-years, and those with sustained low wages, 275 deaths per 10 000 person-years. In models adjusted for key sociodemographic variables, sustained low-wage earning was associated with mortality (hazard ratio [HR], 1.35; 95% CI, 1.07-1.71) and excess deaths (66; 95% CI, 6.6-125); these findings were attenuated with additional adjustments for economic and health covariates. Significant excess death and elevated mortality risk were observed for workers with sustained low-wage exposure and employment fluctuations (eg, for sustained low-wage × employment fluctuated, HR, 2.18; 95% CI, 1.35-3.53; for sustained low-wage × stable employment, HR, 1.17; 95% CI, 0.89,-1.54; P for interaction = .003). Conclusions and Relevance: Sustained low-wage earning may be associated with elevated mortality risk and excess deaths, especially when experienced alongside unstable employment. If causal, our findings suggest that social and economic policies that improve the financial standing of low-wage workers (eg, minimum wage laws) could improve mortality outcomes.

Depressive symptoms mediate the relationship between sustained food insecurity and cognition: a causal mediation analysis.

PURPOSE: This study aimed to investigate the association of change in food insecurity over time with cognitive function in midlife, and whether depressive symptoms mediated that relationship. METHODS: We used longitudinal data from the Coronary Artery Risk Development in Young Adults study. Change in food insecurity in 2000-2005 was coded as "persistently food-secure," "persistently food-insecure," "became food-insecure," and "became food-secure." Depressive symptoms were measured in 2010, and cognitive function was measured in 2015. Multivariable linear regression controlled for sociodemographic and cardiovascular health factors was used. We also conducted causal mediation analysis. RESULTS: Our study population included 2448 participants (57.23% female and 43.18% Black, mean age = 40.31 in 2000). Compared with persistent food security, persistently and became food-insecure were associated with worse cognition, particularly with processing speed (ßpersistent = -0.20 standard unit, 95% CI = -0.36, -0.04; ßbecame = -0.17, 95% CI = -0.31, -0.03), and these associations appeared mediated by depressive symptoms (proportion-mediated = 14% for persistently food-insecure and 18% for became food-insecure). CONCLUSIONS: Persistent and transition to food insecurity were associated with worse cognition, both directly and indirectly through increasing depressive symptoms. Targeting food insecurity or depressive symptoms among persistently or became food-insecure individuals may have the potential to slow premature cognitive aging.

Racial Differences in Employment and Poverty Histories and Health in Older Age.

INTRODUCTION: Black Americans encounter more barriers in the job market and earn less than White Americans. However, the extent to which racial disparities in employment and poverty histories impact health is not fully understood. This study characterized employment‒poverty histories for Black and White middle-aged adults and examined their association with health. METHODS: Respondents born in 1948-1953 and enrolled in the 2004 Health and Retirement Study (NBlack=555, NWhite=2,209) were included. Sequence analysis grouped respondents with similar employment‒poverty trajectories from 2004 to 2016, and confounder-adjusted regression analyses estimated the associations between these trajectories and health in 2018. Analyses were conducted in 2021-2022. RESULTS: More than 23% of Black respondents experienced both employment and poverty fluctuations, including bouts of extreme poverty (<50% of the federal poverty threshold), whereas no trajectory for White respondents included extreme poverty. Adversities in employment‒poverty were associated with worse health. For example, among Black respondents, those who experienced both employment and poverty fluctuations had worse cognition than those employed and not poor (ß= -0.55 standardized units, 95% CI= -0.81, -0.30). Similarly, among White respondents, those who experienced employment fluctuations had worse cognition than those employed (ß= -0.35, 95% CI= -0.46, -0.24). Notably, the employed and not poor trajectory was associated with worse survival among Black respondents than among White respondents. CONCLUSIONS: Employment fluctuations were associated with worse health, especially cognitive function, where the association was stronger among Black Americans who experienced both employment fluctuations and poverty. Findings highlight the importance of enhancing employment stability and of antipoverty programs, especially for Black Americans.

Associations of Religious Service Attendance With Cognitive Function in Midlife: Findings From The CARDIA Study.

OBJECTIVES: Growing evidence suggests that religiosity is an important social determinant of health, including cognitive health. Yet most prior work focused on older adults or was conducted in racially and denominationally homogeneous regional samples. This study investigates the association of religious service attendance in midlife with cognitive function later in midlife. METHODS: Using data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, a racially and geographically diverse prospective cohort study, we explored the association of religious service attendance in midlife with cognitive function 5 years later. Cognitive function was measured using four cognitive tests administered by CARDIA technicians. Multivariable linear regression was used for analyses. Primary analyses controlled for sociodemographics, physical health, depression, and prior religious involvement. Sensitivity analyses additionally controlled for baseline cognition and social support. RESULTS: Our study population included 2,716 participants (57.2% female, 44.9% Black, and mean age 50). In primary analyses, attending services more than weekly (compared to never) in midlife was associated with better global cognition (ß = 0.14 standard deviations, 95% [confidence interval] CI = 0.02, 0.26) and verbal memory (ß = 0.17 standard deviations, 95% CI = 0.04, 0.30), but not with processing speed (ß = 0.04 standard deviations, 95% CI = -0.08, 0.16). A reverse association was observed with executive function (ß = -0.16 standard deviations, 95% CI = -0.30, -0.02). Most findings persisted in analyses accounting for loss to follow-up via inverse probability weighting. DISCUSSION: Our findings suggest that frequent involvement in religious services at midlife is associated with better global cognition and verbal memory but worse executive function. There was no association with processing speed.

Association Between Supplemental Nutrition Assistance Program Use and Memory Decline: Findings From the Health and Retirement Study.

BACKGROUND AND OBJECTIVES: Studies on the effect of the Supplemental Nutrition Assistance Program (SNAP) on the cognitive health of older adults are scarce. We sought to examine the associations between SNAP use and memory decline among SNAP-eligible US older adults. METHODS: Participants aged 50+ years and SNAP-eligible in 1996 from the Health and Retirement Study were included. Participants' SNAP eligibility was constructed using federal criteria. Participants also self-reported whether they used SNAP. Memory function was assessed biennially from 1996 through 2016 using a composite score. To account for preexisting differences in characteristics between SNAP users and nonusers, we modeled the probability of SNAP use using demographic and health covariates. Using linear mixed-effects models, we then modeled trajectories of memory function for SNAP users and nonusers using inverse probability (IP) weighting and propensity score (PS) matching techniques. In all models, we accounted for study attrition. RESULTS: Of the 3,555 SNAP-eligible participants, a total of 15.7% were SNAP users. At baseline, SNAP users had lower socioeconomic status and a greater number of chronic conditions than nonusers and were more likely to be lost to follow-up. Our multivariable IP-weighted models suggested that SNAP users had worse memory scores at baseline but slower rates of memory decline compared with nonusers (the annual decline rate is -0.038 standardized units [95% CI = -0.044 to -0.032] for users and -0.046 [95% CI = -0.049 to -0.043] for nonusers). Results were slightly stronger from the PS-matched sample (N = 1,014) (the annual decline rate was -0.046 units [95% CI = -0.050 to -0.042] for users and -0.060 units [95% CI = -0.064 to -0.056] for nonusers). Put in other words, our findings suggested that SNAP users had approximately 2 fewer years of cognitive aging over a 10-year period compared with nonusers. DISCUSSION: After accounting for preexisting differences between eligible SNAP users and nonusers as well as differential attrition, we find SNAP use to be associated with slower memory function decline.

Sufficient component cause simulations: an underutilized epidemiologic teaching tool.

Simulation studies are a powerful and important tool in epidemiologic teaching, especially for understanding causal inference. Simulations using the sufficient component cause framework can provide students key insights about causal mechanisms and sources of bias, but are not commonly used. To make them more accessible, we aim to provide an introduction and tutorial on developing and using these simulations, including an overview of translation from directed acyclic graphs and potential outcomes to sufficient component causal models, and a summary of the simulation approach. Using the applied question of the impact of educational attainment on dementia, we offer simple simulation examples and accompanying code to illustrate sufficient component cause-based simulations for four common causal structures (causation, confounding, selection bias, and effect modification) often introduced early in epidemiologic training. We show how sufficient component cause-based simulations illuminate both the causal processes and the mechanisms through which bias occurs, which can help enhance student understanding of these causal structures and the distinctions between them. We conclude with a discussion of considerations for using sufficient component cause-based simulations as a teaching tool.

Association of Low Hourly Wages in Middle Age With Faster Memory Decline in Older Age: Evidence From the Health and Retirement Study.

Little research has investigated the long-term relationship between low wages and memory decline, despite the growing share of low-wage workers in the US labor market. Here, we examined whether cumulative exposure to low wages over 12 years in midlife is associated with memory decline in later life. Using 1992-2016 data from the Health and Retirement Study, we analyzed data from 2,879 individuals born in 1936-1941 using confounder-adjusted linear mixed-effects models. Low-wage work was defined as an hourly wage lower than two-thirds of the federal median wage for the corresponding year and was categorized into "never," "intermittent," and "sustained" based on wages earned from 1992 to 2004. Memory function was measured at each study visit from 2004 to 2016 via a memory composite score. The confounder-adjusted annual rate of memory decline among "never" low-wage earners was -0.12 standard units (95% confidence interval: -0.13, -0.10). Compared with this, memory decline among workers with sustained earning of low midlife wages was significantly faster (ßtime×sustained = -0.014, 95% confidence interval: -0.02, -0.01), corresponding to an annual rate of -0.13 standard units for this group. Sustained low-wage earning in midlife was significantly associated with a downward trajectory of memory performance in older age. Enhancing social policies to protect low-wage workers may be especially beneficial for their cognitive health.

Comparing different operationalizations of allostatic load measured in mid-life and their patterning by race and cumulative life course socioeconomic status.

Since its conceptualization, there has been a lack of consensus on the best way to operationalize allostatic load (AL). As a marker of the cumulative, physiological wear and tear on the body resulting from chronic exposure to stressors, it follows that AL should be higher among people who have faced more stressful life experiences. Thus, the purpose of this study was to construct AL scores using different operationalizations and, as a measure of construct validity, compare whether each construction produced expected disparities in AL by race and a composite socioeconomic status (SES) variable which accounts for measures over the life course; we also explored differences by sex. We conducted the study in a sample of 45-52-year-old offspring from the Child Health and Development Studies, a longitudinal birth cohort established in the early 1960s. AL scores were constructed in 6 different ways and included 10 biomarkers from inflammatory, neuroendocrine, cardiovascular, and metabolic systems. Our main approach to constructing AL was to sum across high-risk biomarker quartiles, correct for medication use, and use sex-specific high-risk quartiles for specific biomarkers. Alternative constructions did not use sex-specific quartiles and/or weighted biomarkers within subsystems and/or did not correct for medication use. We estimated differences in AL scores by race, SES, sex and their pairwise interactions. All constructions of AL, including the main approach, produced expected disparities by race (higher scores for Black vs. non-Black participants) and life course SES (higher scores for low vs. high SES participants). However, disparities by sex only emerged when the AL score was constructed via approaches that did not use sex-specific high-risk quartiles; for these alternative constructions, overall, female participants had higher AL scores than male participants and Black female participants had the highest AL scores in the sample. For most constructions, the pairwise interaction between sex and SES, showed a stronger disparity in AL scores between low and high-SES female compared with low- and high-SES male participants; this suggests that, in terms of lowering AL, high life course SES may be more important for female than male participants. In conclusion, our results suggest that the basic AL concept is consistently expressed in different operationalizations, making it an especially useful and robust tool for understanding disparities by race and SES.

Racial Residential Segregation in Young Adulthood and Brain Integrity in Middle Age: Can We Learn From Small Samples?

Racial residential segregation is associated with multiple adverse health outcomes in Black individuals. Yet, the influence of structural racism and racial residential segregation on brain aging is less understood. In this study, we investigated the association between cumulative exposure to racial residential segregation over 25 years (1985-2010) in young adulthood, as measured by the Getis-Ord Gi* statistic, and year 25 measures of brain volume (cerebral, gray matter, white matter, and hippocampal volumes) in midlife. We studied 290 Black participants with available brain imaging data who were enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) Study, a prospective cohort study. CARDIA investigators originally recruited 2,637 Black participants aged 18-30 years from 4 field centers across the United States. We conducted analyses using marginal structural models, incorporating inverse probability of treatment weighting and inverse probability of censoring weighting. We found that compared with low/medium segregation, greater cumulative exposure to a high level of racial residential segregation throughout young adulthood was associated with smaller brain volumes in general (e.g., for cerebral volume, ß = -0.08, 95% confidence interval: -0.15, -0.02) and with a more pronounced reduction in hippocampal volume, though results were not statistically significant. Our findings suggest that exposure to segregated neighborhoods may be associated with worse brain aging.

Statins and Cognitive Decline in the Cardiovascular Health Study: A Comparison of Different Analytical Approaches.

BACKGROUND: Despite their well-established benefits for the prevention of cardiovascular disease, robust evidence on the effects of statins on cognition is largely inconclusive. We apply various study designs and analytical approaches to mimic randomized controlled trial effects from observational data. METHODS: We used observational data from 5 580 participants enrolled in the Cardiovascular Health Study from 1989/1990 to 1999/2000. We conceptualized the cohort as an overlapping sequence of nonrandomized trials. We compared multiple selection (eligible population, prevalent users, new users) and analytic approaches (multivariable adjustment, inverse-probability treatment weights, propensity score matching) to evaluate the association between statin use and 5-year change in global cognitive function, assessed using the Modified Mini-Mental State Examination (3MSE). RESULTS: When comparing prevalent users to nonusers (N = 2 772), statin use was associated with slower cognitive decline over 5 years (adjusted annual change in 3MSE = 0.34 points/year; 95% CI: 0.05-0.63). Compared to prevalent user design, estimates from new user designs (eg, comparing eligible statin initiators to noninitiators) were attenuated showing either null or negative association, though not significant. For example, in a propensity score-matched sample of statin-eligible individuals (N = 454), the annual 3MS change comparing statin initiators to noninitiators was -0.21 points/year (95% CI: -0.81 to 0.39). CONCLUSIONS: The association of statin use and cognitive decline is attenuated toward the null when using rigorous analytical approaches that more closely mimic randomized controlled trials. Point estimates, even within the same study, may vary depending on the analytical methods used. Further studies that leverage natural or quasi experiments around statin use are needed to replicate our findings.

Could maternal thyroid function during pregnancy affect daughters' age at menarche through child growth? A mediation analysis.

Early menarche is associated with adverse health outcomes during adolescence as well as breast and other reproductive cancers later in adulthood. However, the causes of early menarche and the pathways through which they operate are not fully understood. Though maternal thyroid function during pregnancy affects child growth, and rapid childhood growth is associated with a decreased age at menarche, the relationship between prenatal maternal thyroid function and daughters' age at menarche has not been examined. We conducted a mediation analysis in a historical cohort of 260 mother-child pairs to estimate the total and indirect effects of maternal prenatal thyroid function on daughters' age at menarche. No association was observed between thyroid stimulating hormone (TSH) or anti-thyroid peroxidase antibodies (ATPO) and daughters' age at menarche. Using a sample-specific, a-priori cutoff at the 10th percentile, low levels of maternal free thyroxine (FT4) were associated with earlier daughter age at menarche, with a hazard ratio (95 % CI) of 1.70 (1.02, 2.84) comparing the bottom 10th percentile with the top 90th percentile of exposure levels. Higher maternal FT4 was associated with rapid child weight gain from ages 5-9, and rapid child weight gain from ages 5-9 was associated with earlier age at menarche; the estimated indirect effect of this pathway was null. While maternal FT4 is associated with earlier age at menarche in daughters, this is not mediated by rapid weight gain in our study population, suggesting that maternal FT4 is operating through a different pathway.

Is the Way Forward to Step Back? Documenting the Frequency With Which Study Goals Are Misaligned With Study Methods and Interpretations in the Epidemiologic Literature.

In any research study, there is an underlying process that should begin with a clear articulation of the study's goal. The study's goal drives this process; it determines many study features, including the estimand of interest, the analytic approaches that can be used to estimate it, and which coefficients, if any, should be interpreted. Misalignment can occur in this process when analytic approaches and/or interpretations do not match the study's goal; misalignment is potentially more likely to arise when study goals are ambiguously framed. In this study, misalignment in the observational epidemiologic literature was documented and how the framing of study goals contributes to misalignment was explored. The following 2 misalignments were examined: use of an inappropriate variable selection approach for the goal (a "goal-methods" misalignment) and interpretation of coefficients of variables for which causal considerations were not made (e.g., Table 2 Fallacy, a "goal-interpretation" misalignment). A random sample of 100 articles published 2014-2018 in the top 5 general epidemiology journals were reviewed. Most reviewed studies were causal, with either explicitly stated (n = 13; 13%) or associational-framed (n = 71; 69%) aims. Full alignment of goal-methods-interpretations was infrequent (n = 9; 9%), although clearly causal studies (n = 5 of 13; 38%) were more often fully aligned than were seemingly causal ones (n = 3 of 71; 4%). Goal-methods misalignments were common (n = 34 of 103; 33%), but most frequently, methods were insufficiently reported to draw conclusions (n = 47; 46%). Goal-interpretations misalignments occurred in 31% (n = 32) of the studies and occurred less often when the methods were aligned (n = 2; 2%) compared with when the methods were misaligned (n = 13; 13%).

Explaining the Black-white depression paradox: Interrogating the Environmental Affordances Model.

The Environmental Affordances (EA) model posits that Black Americans' engagement with unhealthy behaviors (i.e. smoking, alcohol use, eating calorie-dense foods) to cope with stressor exposure may simultaneously account for their observed greater risk of chronic physical illness, and their observed equal or lesser prevalence of depression, relative to white Americans - the so-called "Black-white depression paradox." However, the specific mechanisms through which such effects might arise have been theorized and analyzed inconsistently across studies, raising concerns regarding the appropriateness of existing empirical tests of the model as well as the validity of the conclusions. We specify the two mechanisms most consistent with the EA model - 'Mediation-only' and 'Mediation and Modification' - and derive a priori predictions based on each. We systematically test these pathways using a subset of 559 participants of the Child Health and Development Study who were included in an adult follow-up study between 2010 and 2012 and self-identified as Black or white. Results failed to support either of the two mechanisms derived from the EA model, challenging the validity and utility of the model for explaining racial differences in depression; efforts to develop alternative hypotheses to explain the paradox are needed.

Tracking of Obesity in Childhood into Adulthood: Effects on Body Mass Index and Fat Mass Index at Age 50.

Background: Obesity is present in 17% of US youth, age 2-19 years, but the extent to which obesity in childhood is associated with higher BMI and fat mass in middle age is unclear. In this study, links between childhood body size and BMI and body composition at age ∼50 were assessed. Methods: Child Health and Development Studies participants, born between 1960 and 1963 in Alameda County, and still living in California, from whom anthropometric data were collected at age 5, 9-11, and/or 15-17 years were followed-up at age ∼50 for anthropometric outcomes (251 women; 249 men). Linear regression analyses assessed whether overweight (85th to <95th BMI percentile) or obesity (≥95th BMI percentile) at age 5 were associated with BMI, fat mass index (FMI), and lean mass index (LMI) at age ∼50. Results: At age 50, participants with obesity at age 5 had BMI scores that were 6.51 units higher [95% confidence interval (CI) = 3.67-9.35] than participants who were normal weight at age 5; FMI and LMI scores were 4.15 (95% CI = 1.98-6.32) and 2.36 (95% CI = 1.45-3.26) units higher, respectively. However, obesity experienced at age 5 had only a modest positive predictive value for predicting the presence of obesity at age 50 (67%), whereas obesity present at age 15-17 had a higher positive predictive value (86%). Conclusions: The experience of obesity at age 5 for members of this birth cohort was associated with significantly higher BMI, FMI, and LMI at age ∼50.

Who is in this study, anyway? Guidelines for a useful Table 1.

OBJECTIVE: Epidemiologic and clinical research papers often describe the study sample in the first table. If well-executed, this "Table 1" can illuminate potential threats to internal and external validity. However, little guidance exists on best practices for designing a Table 1, especially for complex study designs and analyses. We aimed to summarize and extend the literature related to reporting descriptive statistics. STUDY DESIGN AND SETTING: In consultation with existing guidelines, we synthesized and developed reporting recommendations driven by study design and focused on transparency related to potential threats to internal and external validity. RESULTS: We describe a basic structure for Table 1 and discuss simple modifications in terms of columns, rows, and cells to enhance a reader's ability to judge both internal and external validity. We further highlight several analytic complexities common in epidemiologic research (missing data, sample weights, clustered data, and interaction) and describe possible variations to Table 1 to maintain and add clarity about study validity in light of these issues. We discuss considerations and tradeoffs in Table 1 related to breadth and comprehensiveness vs. parsimony and reader-friendliness. CONCLUSION: We anticipate that our work will guide authors considering layouts for Table 1, with attention to the reader's perspective.