Early-Life Exposure to War and Later-Life Physical Functional Health.

OBJECTIVES: A growing body of research shows that early-life exposure to war has adverse effects on later-life health. Research has emphasized the importance of exposure timing implicating domain-specific developmental processes and associated critical/sensitive periods. This study looks at the impacts of early childhood war exposure and the repercussions for later-life physical and functional health, with a focus on time of exposure as a source of variability. METHODS: We use residential histories from the Survey of Health Ageing, and Retirement in Europe linked to external data on the location and timing of hostilities to examine the impact of early-life exposure to World War II on later-life physical and functional health. RESULTS: Exposure to war increases the risk of objective (grip strength, chair rise, and peak expiratory flow) and self-reported (mobility limitations and activities of daily living) measures of functional health. Effects are especially pronounced for those born during the war and for those with more prolonged exposures. There is little evidence that the impact of war is mediated by war-related hardships, socioeconomic conditions, health behaviors, or adult chronic disease. DISCUSSION: Our results suggest early-life exposure to war has a lasting impact on physical functional health. Exposure appears to largely operate via direct effects, indicative of altered initial development of physical capacity in early life. Because exposure was so pervasive among some cohorts of older individuals, understanding the health of present older European populations requires wrestling with the residual consequences of wartime exposure at the start of their lives.

Childhood exposure to war and adult onset of cardiometabolic disorders among older Europeans.

Childhood exposure to contexts of war is a common occurrence among current and recent cohorts of children in various parts of the world. It was also common among older cohorts across Europe. Utilizing the Survey of Health, Ageing, and Retirement in Europe (SHARE) the present study links early life course residential histories with detailed information on the timing and location of hostilities during WWII to address three questions: 1) is childhood exposure to war associated with earlier onset of cardiometabolic disease (cardiovascular disease, hypertension, high cholesterol, and diabetes)? 2) did this additional risk vary depending on the timing of first exposure? 3) did this additional risk manifest via different life course pathways depending on exposure timing? Results demonstrate that exposure to war is associated with increased lifetime risk of cardiovascular disease, diabetes, high cholesterol, and hypertension and that this association is strongly concentrated among cohorts exposed in utero or during early childhood (e.g., before age 8). The results also suggest that the impact of war exposure on cardiometabolic disorders are likely to be direct, operating through latent biological processes rather than through childhood hardship, stunting of adult socioeconomic attainment, or elevated risk-taking behaviors.

Cohort Trends in the Burden of Multiple Chronic Conditions Among Aging U.S. Adults.

OBJECTIVES: Multimorbidity, also referred to as multiple chronic conditions (MCCs), is the concurrent presence of 2 or more chronic health conditions. Increasing multimorbidity represents a substantial threat to the health of aging populations. Recent trends suggest greater risk of poor health and mortality among later-born cohorts, yet we are unaware of work examining cohort differences in multimorbidity among aging U.S. adults. METHODS: We examine intercohort variation in MCC burden in adults aged 51 years and older using 20 years (n = 33,598; 1998-2018) of repeated assessment drawn from the Health and Retirement Study. The index of MCCs included 9 chronic conditions (heart disease, hypertension, stroke, diabetes, arthritis, lung disease, cancer excluding skin cancer, high depressive symptoms, and cognitive impairment). We used linear mixed models with various approaches to estimate age/period/cohort effects to model intercohort patterns in MCC burden. We also explored variation in the specific conditions driving cohort differences in multimorbidity. RESULTS: More recent cohorts had greater MCC burden and developed multimorbidity at earlier ages than those born to prior generations. The burden of chronic conditions was patterned by life-course sociodemographic factors and childhood health for all cohorts. Among adults with multimorbidity, arthritis and hypertension were the most prevalent conditions for all cohorts, and there was evidence that high depressive symptoms and diabetes contributed to the observed cohort differences in multimorbidity risk. DISCUSSION: Our results suggest increasing multimorbidity burden among more recently born cohorts of aging U.S. adults and should inform policy to address diminishing health in aging populations.

Windows of Vulnerability: Consequences of Exposure Timing during the Dutch Hunger Winter.

Prior research on early-life exposures to famine has established in utero development as a critical period of vulnerability to malnutrition. Yet, previous research tends to focus narrowly on this stage, at the expense of a more comprehensive examination of childhood. As a result, the literature has yet to compare the severity of the consequences of exposure to malnutrition across developmentally salient periods. Such comparison is crucial not only in the magnitude of effects but also in the nature of outcomes. Using a restricted population registry-linked health survey, this study examines the Dutch Hunger Winter to provide a comprehensive examination of the long-term consequences of in utero, infant, childhood, and adolescent exposure to famine. The results show malnutrition leads to heterogeneous effects depending on when the exposure occurs. In utero exposure to malnutrition leads to deleterious conditions in physical health and lower socioeconomic attainment. For older cohorts, results suggest a resilience to the effects of malnutrition on physical health in late life, but a higher vulnerability to socioeconomic stunting. Furthermore, the results suggest important gender differences in the long-term impact of malnutrition. Males consistently show stronger negative consequences across a wider array of conditions.

The Long Arm of Conflict: How Timing Shapes the Impact of Childhood Exposure to War.

This paper examines how the timing of childhood exposure to armed conflict influences both the magnitude of the impact it has on later-life health and the pathways through which those impacts manifest. Utilizing the Survey of Health and Retirement in Europe, we examine cohorts of children during World War II. We find that cohorts born during the war show the largest negative effects of exposure on health in later life. The pathways also vary the timing of exposure. Consistent with a latent critical period process, children born during the war experienced increased risk of poor health and illness in childhood, as well as adult cardiometabolic conditions and poor functional health. Conversely, cohorts born before the war experienced more indirect pathways consistent with cumulative disadvantage processes and institutional breakdown. These pathways include stunted socioeconomic attainment, increased risk behaviors, and poorer mental health. Overall, this study emphasizes that the timing of exposure is critical to understanding the long-term health effects of war.

Race, Gender, and Socioeconomic Variations in C-Reactive Protein Using the Health and Retirement Study.

OBJECTIVES: To clarify the relationships among race, gender, and socioeconomic status (SES) with C-reactive protein (CRP). METHOD: The present study analyzed data from 6,521 Black and White respondents aged 51 and older in the Health and Retirement Study, a nationally representative sample of midlife and older adults, to address two aims. We sought to (i) assess the independent associations between race, gender, and SES with CRP concentrations and (ii) test whether race, gender, and SES interacted to produce unequal CRP concentrations cross-sectionally and over a 4-year follow-up. RESULTS: The results demonstrated that race, gender, and SES were each independently associated with baseline CRP, but only SES was associated with CRP at follow-up. Furthermore, race, gender, and education interacted to produce differential CRP levels at baseline. There were incremental benefits for each additional level of education for White men and women, but the relationship between education and CRP was more complicated for Black men and women. Compared with other race/gender groups with less than high school, Black women had the highest and Black men had the lowest levels of CRP. There were no apparent benefits to CRP for Black women with college compared with Black women with high school, while Black men with less than high school and college had similar concentrations of CRP. DISCUSSION: In clarifying the complexity inherent in CRP disparities, this work contributes to a greater understanding of the biological mechanisms underlying racial disparities in leading causes of morbidity and mortality in the United States.

The developmental origins of health and disease in international perspective.

The developmental origins of health and disease and the comparative international approach are two important strands of research exploring population health. Despite the potential insights to be gained from integrating the two approaches, their nexus remains an underexplored frontier. The current study investigates international variation in the early life origins of health among aging cohorts in 13 countries. We examine cross-national differences in exposure to poor childhood health and socioeconomic disadvantage, whether the long-term health associations with those exposures vary across contexts, and whether they persist in the face of subsequent accumulation of socioeconomic and behavioral risk. Finally, we investigate whether childhood health and socioeconomic circumstances help explain between-country differences in later life health. The findings suggest substantial international variation in the exposure to early life health and socioeconomic insults. We also find variation in their association with later life health. However, early life factors appear to play a modest role in explaining international differences in later life health in the contexts examined here.

The Life Course, Cohort Dynamics, and International Differences in Aging Trajectories.

In recent years, population health research has focused on understanding the determinants of later-life health. Two strands of that work have focused on (1) international comparisons of later-life health and (2) assessing the early-life origins of disease and disability and the importance of life course processes. However, the less frequently examined intersection of these approaches remains an important frontier. The present study contributes to the integration of these approaches. We use the Health and Retirement Study family of data sets and a cohort dynamic approach to compare functional health trajectories across 12 high-income countries and to examine the role of life course processes and cohort dynamics in contributing to variation in those trajectories. We find substantial international variation in functional health trajectories and an important role of cohort dynamics in generating that variation, with younger cohorts often less healthy at comparable ages than the older cohorts they are replacing. We further find evidence of heterogeneous effects of life course processes on health trajectories. The results have important implications for future trends in morbidity and mortality as well as public policy.

Estimating the Co-Development of Cognitive Decline and Physical Mobility Limitations in Older U.S. Adults.

This study examines the co-development of cognitive and physical function in older Americans using an age-heterogeneous sample drawn from the Health and Retirement Study (1998-2008). We used multiple-group parallel process latent growth models to estimate the association between trajectories of cognitive function as measured by immediate word recall scores, and limitations in physical function as measured as an index of functional mobility limitations. Nested model fit testing was used to assess model fit for the separate trajectories followed by estimation of an unconditional parallel process model. Controls for demographic characteristics, socioeconomic status, and chronic health conditions were added to the best-fitting parallel process model. Pattern mixture models were used to assess the sensitivity of the parameter estimates to the effect of selective attrition. Results indicated that favorable cognitive health and mobility at initial measurement were associated with faster decline in the alternate functional domain. The cross-process associations remained significant when we adjusted estimates for the influence of covariates and selective attrition. Demographic and socioeconomic characteristics were consistently associated with initial cognitive and physical health but had few relations with change in these measures.

With a Little Help from My Friends? Asymmetrical Social Influence on Adolescent Smoking Initiation and Cessation.

This study investigates whether peer influence on smoking among adolescents is asymmetrical. We hypothesize that several features of smoking lead peers to have a stronger effect on smoking initiation than cessation. Using data from the National Longitudinal Study of Adolescent Health we estimate a dynamic network model that includes separate effects for increases versus decreases in smoking, while also controlling for endogenous network change. We find that the impact of peer influence is stronger for the initiation of smoking than smoking cessation. Adolescents rarely initiate smoking without peer influence but will cease smoking while their friends continue smoking. We discuss the implications of these results for theories of peer influence and health policy.

Social networks and smoking: exploring the effects of peer influence and smoker popularity through simulations.

Adolescent smoking and friendship networks are related in many ways that can amplify smoking prevalence. Understanding and developing interventions within such a complex system requires new analytic approaches. We draw on recent advances in dynamic network modeling to develop a technique that explores the implications of various intervention strategies targeted toward micro-level processes. Our approach begins by estimating a stochastic actor-based model using data from one school in the National Longitudinal Study of Adolescent Health. The model provides estimates of several factors predicting friendship ties and smoking behavior. We then use estimated model parameters to simulate the coevolution of friendship and smoking behavior under potential intervention scenarios. Namely, we manipulate the strength of peer influence on smoking and the popularity of smokers relative to nonsmokers. We measure how these manipulations affect smoking prevalence, smoking initiation, and smoking cessation. Results indicate that both peer influence and smoking-based popularity affect smoking behavior and that their joint effects are nonlinear. This study demonstrates how a simulation-based approach can be used to explore alternative scenarios that may be achievable through intervention efforts and offers new hypotheses about the association between friendship and smoking.

Developmental Origins of Disease and Health Disparities: Limitations and Future Directions.

The developmental origins of disease (DOD) model seeks to replace the traditional epidemiologic risk factor model with a perspective focused on the long-term consequences of nutritional resource scarcity during early life and the developmental trade-offs it creates. Research into the developmental origins of adult chronic disease has progressed substantially in recent years. However, a number of critical issues remain unexplored and under-developed. This chapter discusses some of those issues while providing an interdisciplinary population health perspective on the future of DOD research, with particular attention paid to health disparities and changes that are needed in health policy and intervention. I argue for research to provide greater specificity of the exposures of interest, a more comprehensive understanding of critical periods, and better theoretical and empirical integration of the developmental origins perspective within the life course and across multiple intergenerational processes.

A dynamic model of US adolescents' smoking and friendship networks.

OBJECTIVES: We investigated the associations between smoking and friend selection in the social networks of US adolescents. METHODS: We used a stochastic actor-based model to simultaneously test the effects of friendship networks on smoking and several ways that smoking can affect the friend selection process. Data are from 509 US high school students in the National Longitudinal Study of Adolescent Health, 1994-1996 (46.6% female, mean age at outset=15.4 years). RESULTS: Over time, adolescents' smoking became more similar to their friends. Smoking also affected who adolescents selected as friends; adolescents were more likely to select friends whose smoking level was similar to their own, and smoking enhanced popularity such that smokers were more likely to be named as friends than were nonsmokers, after controlling for other friend selection processes. CONCLUSIONS: Both friend selection and peer influence are associated with smoking frequency. Interventions to reduce adolescent smoking would benefit by focusing on selection and influence mechanisms.

Race/ethnic and nativity disparities in later life physical performance: the role of health and socioeconomic status over the life course.

OBJECTIVES: We examine race/ethnic and nativity differences in objective measures of physical performance (i.e., peak expiratory flow, grip strength, and gait speed) in a nationally representative sample of older Whites, Blacks, and Hispanics. We also examine whether detailed measures of childhood and adult health and socioeconomic status (SES) mediate race/ethnic differences in physical performance. METHOD: We use data from the Health and Retirement Study, a population-based sample of older Americans born before 1947, and 3 measures of physical performance. Nested ordinary least squares models examine whether childhood and adult health and SES mediate race/ethnic differences in performance. RESULTS: We find large and significant race/ethnic and nativity differences in lung function, grip strength, and gait speed. Adjusting for childhood and current adult health and SES reduces race/ethnic differences in physical performance but does not eliminate them entirely. Childhood health and SES as well as more proximal levels of SES are important determinants of race/ethnic disparities in later life physical performance. DISCUSSION: The analysis highlights that a large proportion of race/ethnic and nativity disparities result from health and socioeconomic disadvantages in both early life and adulthood and thus suggests multiple intervention points at which disparities can be reduced.

The importance of family factors to protect against substance use related problems among Mexican heritage and White youth.

INTRODUCTION: This study examined the ability of family cohesion, parental control, and parent-child attachment to prevent adolescents with a history of drug or alcohol use from experiencing subsequent problems related to their use. METHODS: Data came from Wave I and Wave II of the National Longitudinal Study of Adolescent Health and included Mexican heritage and White adolescents who reported alcohol use (n = 4894, 25% prevalence) or any other drug use (n = 2875, 14% prevalence) in their lifetime. RESULTS: Logistic regression results indicate greater parent-child attachment predicted lower risk of experiencing drug use problems (OR = 0.87, 95% CI = 0.77-0.98) while stronger family cohesion predicted lower odds of experiencing drug- (OR = 0.82, 95% CI = 0.70-0.97) or alcohol-related (OR = 0.74, 95% CI = 0.65-0.84) problems. Parental control was also negatively associated with odds of problems related to drug use (OR = 0.93, 95% CI = 0.86-0.99) or alcohol use (OR = 0.94, 95% CI = 0.90-0.99). Results also indicated family cohesion was the only protective factor for Mexican heritage youth while family cohesion and parent-child attachment were protective among White youth. Parental control protected White female adolescents from drug use problems more than males. Mexican heritage male adolescents experienced more protection from drug problems compared to females. CONCLUSION: Findings highlight the need for prevention interventions to emphasize parent-child attachment for White youth and family cohesion for both Mexican-heritage and White youth to decrease adolescent substance users' drug- and alcohol-related problems.

Childhood health and labor market inequality over the life course.

The authors use data from the Health and Retirement Study's Earnings Benefit File, which links Health and Retirement Study to Social Security Administration records, to estimate the impact of childhood health on earnings curves between the ages of 25 and 50 years. They also investigate the extent to which diminished educational attainment, earlier onset of chronic health conditions, and labor force participation mediate this relationship. Those who experience poor childhood health have substantially diminished labor market earnings over the work career. For men, earnings differentials grow larger over the early to middle career and then slow down and begin to converge as they near 50 years of age. For women, earnings differentials emerge later in the career and show no evidence of convergence. Part of the child health earnings differential is accounted for by selection into diminished educational attainment, the earlier onset of chronic disease in adulthood, and, particularly for men, labor force participation.

Do family and parenting factors in adolescence influence condom use in early adulthood in a multiethnic sample of young adults?

Studies show that positive family factors help protect adolescents from engaging in risky sexual activities, but do they continue to protect adolescents as they transition to late adolescence/early adulthood? Using data from the National Longitudinal Study of Adolescent Health, we examined whether family support, parent-child closeness, parental control/monitoring of adolescent behaviors and parent-child communication about sex, assessed in adolescence, were related to condom use in late adolescence/early adulthood among African American (n = 1,986), Chinese American (n = 163), Mexican American (n = 1,011) and White (n = 6,971) youth. Controlling for demographic variables and number of sex partners, the results showed that family support was positively related and parent-child communication was negatively related to condom use for the sample as a whole and for the white sample, but not for the other groups. Parent-child communication about sex and parental control were negatively related to condom use in the Chinese American sample. None of the family factors was related to condom use in the African American or Mexican American samples. Overall, parents talked more with daughters than sons about sexual matters. Condom use was most common among African Americans and among males. Greater attention to cultural expectations regarding sex and gender roles, as well as the causal ordering of effects, are important directions for future research.

Health and the structure of adolescent social networks.

Much research has explored the role of social networks in promoting health through the provision of social support. However, little work has examined how social networks themselves may be structured by health. This article investigates the link between individuals' health and the characteristics of their social network positions. We first develop theoretical predictions for how health may influence the structure of adolescent networks. We then test these predictions using longitudinal analysis of the National Longitudinal Study of Adolescent Health (Add Health). We find important relationships between the health status of adolescents and the characteristics of the social network positions within which they are embedded. Overall we find that adolescents in poor health form smaller local networks and occupy less central global positions than their healthy peers. These results also have implications for social network research, expanding the scope of factors responsible for the network positions individuals occupy.