Disparities in Stress Exposure and Later-Life Disability.

Background and Objectives: Drawing from cumulative inequality theory and the weathering hypothesis, this study examined the relationship between life-course stress exposure (measured cumulatively and by domains) and the onset of disability in later life among White, Black, U.S.-born Hispanic, and foreign-born Hispanic older adults. Research Design and Methods: Cross-sectional and longitudinal models were estimated using nationally representative data from the Health and Retirement Study (N = 11,483). We used logistic regression models to examine associations between stress exposure and Wave 1 disability (i.e., occurrence), and Weibull-accelerated failure-time models to examine the relationship between stress exposure and age of onset of disability 12-14 years later (i.e., incidence). We tested for moderation between stress and disability by race, ethnicity, and Hispanic nativity. Results: At Wave 1, higher odds of disability occurrence were associated with cumulative stress burden (CSB; odds ratio [OR] = 4.93, 95% confidence interval [CI]: 2.95-8.23). In a model specifying domains of stressors, disability occurrence was associated with childhood financial strain (OR = 1.22, CI: 1.01-1.46), lifetime traumatic events (OR = 1.92, CI: 1.41-2.62), neighborhood disadvantage (OR = 1.32, CI: 1.01-1.73), and major lifetime discrimination (OR = 1.64, CI: 1.12-2.41). Over time, earlier onset of disability was associated with CSB (ß = -0.39), childhood traumatic events (ß = -0.16), adult financial strain (ß = -0.17), everyday discrimination (ß = -0.15), and major lifetime discrimination (ß = -0.13). The effect of childhood traumatic events on the transition to disability was stronger for U.S.-born Hispanic adults than White adults (occurring 33% earlier). Discussion and Implications: To reduce racial, ethnic, and nativity disparities in disability, it is important to consider the historical and structural disadvantages associated with stress exposure across the life course. It is also important to acknowledge that nativity influences stratification processes associated with disparities in racial and ethnic health trajectories.

Educational Inequalities in Dual-Function Life Expectancy.

OBJECTIVES: This study investigates educational inequalities in dual functionality, a new concept that captures a combination of physical and cognitive functioning, both of which are important for independent living and quality of life. METHODS: Using data from the Health and Retirement Study and the National Health Interview Survey Linked Mortality Files, we define a measure of dual functionality based on the absence of limitations in activities of daily living and dementia. We estimate age-graded dual-function rates among adults 65+ and age-65 dual-function life expectancy across levels of education stratified by gender. RESULTS: In their mid-60s, 67% of women with less than a high school degree manifest dual functionality as compared with over 90% of women with at least a 4-year college degree. A similar pattern holds among men. These education-based gaps in dual functionality remain across later life, even as dual-function rates decline at older ages. Lower dual-function rates among older adults with less education translate into inequalities of 6.7 and 7.3 years in age-65 dual-function life expectancy between men and women, respectively, with at least a 4-year college degree compared to their counterparts with less than a high school degree. DISCUSSION: Older adults, particularly women, with less than a high school degree are estimated to live a smaller percentage of their remaining years with dual functionality compared with older adults with at least a college degree. These inequalities have implications for the distribution of caregiving resources of individuals, family members, and the broader healthcare community.

Is Early-Life Enrichment Associated With Better Cognitive Function Among Older Adults? Examining Home and School Environments.

Objectives: We examine whether early-life enrichment, involving varied and stimulating activities to enhance cognitive function during childhood and adolescence, is associated with cognitive function in later life and whether the benefits persist over time. Methods: Growth curve models were used to examine up to five waves of data from the Health and Retirement Study-a nationally representative survey of adults 50 years and older (N = 10,070). We constructed separate measures of early-life enrichment to distinguish sources of influence (i.e., enriched home environment and enriched school environment). Global cognitive function was assessed with a modified version of the Telephone Interview for Cognitive Status. Results: Greater enrichment in each environment was incrementally associated with better cognitive function at baseline, but enrichment was not associated with change in cognitive function over time. Discussion: Receiving enrichment from multiple environments during sensitive periods of cognitive development may be advantageous for cognitive functioning in later life.

Early Origins of Frailty: Do Later-Life Social Relationships Alter Trajectories of Decline?

Objectives: Social relationships are widely regarded as salubrious, but do they mediate the influence of childhood experiences on frailty in later life? Drawing from cumulative inequality theory, we assess the influence of childhood experiences and adult relationships on frailty trajectories. Methods: We analyzed data from the Health and Retirement Study to examine the influence of six domains of childhood experiences and social relationships on frailty trajectories over 8 years. Mediation analyses were completed with structural equation models. Results: Risky adolescent behavior, chronic disease, and impairments during childhood are associated directly with higher risk of initial frailty, but not over time. More social roles and higher social support mediate the relationship between childhood experiences and frailty, and the effect of more social roles continues over time. Discussion: This study provides compelling evidence that supportive social relationships mediate the risk and severity of frailty in later life associated with noxious childhood experiences.

Race, everyday discrimination, and cognitive function in later life.

Discrimination is pernicious in many ways, but there are inconsistent findings regarding whether it is harmful to cognitive function in later life. To address the inconsistency, we use two closely related concepts of everyday discrimination to predict cognitive trajectories in a diverse sample. Using data from the Health and Retirement Study (HRS), we examine whether the frequency of discrimination, measured at baseline with six questions, is related to poorer cognitive function and change in function over time (2008-2016). Age at baseline ranged from 53 to 100. Growth curve models of initial cognitive function and change in function were estimated. Everyday global discrimination was associated with poorer initial cognition and slower declines over time, and these relationships were not moderated by race and ethnicity. By contrast, the relationship between everyday racial discrimination and cognition was moderated by race: more frequent everyday racial discrimination was associated with better initial cognitive function among Black adults but not among Hispanic and White adults. Discrimination is a multifaceted concept, and specific types of discrimination manifest lower or higher cognitive function during later life for White, Black, and Hispanic adults.

Dual Functionality in Later Life.

Gerontologists have long shown interest in both longevity and quality of life during later life, but considerable debate has ensued as scholars sought to integrate the two. Drawing from research on the topics of exceptional longevity, successful aging, and active life expectancy, we propose the concept of dual functionality to examine how humans reach advanced ages while maintaining physical and cognitive function. Dual functionality refers to being free of both physical and cognitive impairment. The loss of dual functionality challenges social networks to respond to the functional loss and is a harbinger of additional losses. Evidence of change in the percent of the older population maintaining dual functionality would be helpful for evaluating public health policies to aid quality of life during later life. This article is based on the first author's Robert W. Kleemeier Award Lecture at The Gerontological Society of America 2022 Annual Scientific Meeting.

Racial-Ethnic Disparities in Dual-Function Life Expectancy.

BACKGROUND: This study develops a new concept, dual functionality, that integrates physical and cognitive function. We use the concept to define a measure of dual-function life expectancy (2FLE) and assess racial-ethnic inequalities in aging. METHODS: Drawing on data from the National Health Interview Survey Linked Mortality Files and the Health and Retirement Study, we define dual functionality as having no limitations in activities of daily living and being free of dementia. We use this measure and Sullivan life tables to estimate age-50 total life expectancy and age-50 2FLE for women and men across 4 racial-ethnic and nativity groups. RESULTS: At ages 50-54, between 79.0% (95% CI: 73.5, 84.5) and 87.6% (95% CI: 84.0, 91.2) of (non-Hispanic) Black, foreign-born Hispanic, and U.S.-born Hispanic women and men remain dual functional as compared with 90.4% (95% CI: 89.3, 91.4) and 91.4% (95% CI: 90.2, 92.5) of (non-Hispanic) White women and men, respectively. These and corresponding racial-ethnic disparities in dual functionality through ages 85 and older translate into substantial inequalities in 2FLE. For instance, the Black-White gap in age-50 2FLE is 6.9 years (95% CI: -7.5, -6.4) for women and 6.0 years (95% CI: -6.6, -5.4) for men. CONCLUSIONS: Black, foreign-born Hispanic, and U.S.-born Hispanic older adults are estimated to live a smaller percentage of their remaining years with dual functionality than White older adults. These results reveal stark racial-ethnic inequalities in aging that have significant implications for quality of life, caregiving, and health needs.

Subjective Memory Decline Predicts Incident Cognitive Impairment Among White-But Not Black or Hispanic-Older Adults.

BACKGROUND AND OBJECTIVES: This study investigates whether subjective memory decline (SMD) in a racially diverse sample of older adults without cognitive impairment at baseline is associated with incident cognitive impairment during a 12-year follow-up period. RESEARCH DESIGN AND METHODS: With panel data from a national sample (N = 9,244) of cognitively intact Black, White, and Hispanic Americans 65 years or older in 2004, we examine if SMD is associated with the loss of normal cognition by 2016. Cognitive status was assessed every 2 years with a modified version of the Telephone Interview for Cognitive Status to identify the transition from normal cognition to cognitive impairment. RESULTS: Estimates from Weibull accelerated failure-time models reveal that SMD is associated with earlier incident cognitive impairment (time ratio = 0.96, p < .05). In subsequent models stratified by race-ethnicity, this association was evident among White respondents (time ratio = 0.95, p < .01) but not among Black, U.S.-born Hispanic, or foreign-born Hispanic respondents. DISCUSSION AND IMPLICATIONS: Given that the prognostic validity of SMD differs by race and ethnicity, caution is warranted when using it as a screening or clinical tool in diverse populations.

Disciplinary Roots of 300 Top-Ranked Scientific Contributors to Gerontology: From Legacy to Enriching Our Discovery.

Gerontology is viewed by many as a multidisciplinary field of inquiry, but which disciplines have had the greatest impact on research in the field? Combining data from a composite score incorporating multiple citation indicators with information on the highest degree, we examine the disciplinary origins of the 300 top-ranked scholars in gerontology. Despite efforts for gerontology to be distinct from geriatrics, more than 30 percent of the most influential scholars in gerontology during the past 6 decades hold a degree in medicine. Other fields of the leading contributors to gerontology include psychology, sociology, biology, biochemistry, and genetics. Although the disciplinary origins of gerontology will likely shift in the coming decades, we conclude that biomedical sciences are likely to remain core to the development of gerontology. To build on the scientific contributions of leading scholars in gerontology, future research should reflect conceptual precision and scientific innovation while prioritizing methodological rigor and transparency.

Volunteer Engagement and Systemic Inflammation: Does Helping Others Benefit Oneself?

BACKGROUND AND OBJECTIVES: Although research on the health benefits of volunteering has proliferated, most studies are cross-sectional and rely on self-reported measures of health. Drawing from role theory, the objectives of this study are to examine if (a) volunteering engagement is related to systemic inflammation in later life, as measured by C-reactive protein (CRP); (b) the effect of volunteering varies by age; and (c) volunteering is related to change in CRP over time. RESEARCH DESIGN AND METHODS: This study uses 4 waves of data from the Health and Retirement Study, a nationally representative survey of adults 50 years or older. Nested linear regression models were used to examine the relationship between volunteer engagement and CRP concentration in later life. Residualized regression models were used to examine the effects of volunteer engagement on change in CRP. RESULTS: Results revealed that volunteering is modestly associated with lower CRP concentration, but only for respondents 65+. Highly engaged volunteers had lower CRP than both mid-level and nonvolunteers. Longitudinal analyses revealed a leveling of the beneficial effect of volunteering by age, indicative of reduced returns among the oldest respondents in our sample. DISCUSSION AND IMPLICATIONS: These results support previous studies that volunteering, and doing so at a high engagement level, is associated with slightly lower levels of CRP. Leaders in medicine, public health, and social services should consider implementing volunteering programs for older adults.

Measuring Physical Activity Regulatory Styles and Identity Among Adults 55 Years or Older.

Objectives. The purpose of this study was to examine the psychometric properties of modified versions of the Behavioral Regulation in Exercise Questionnaire and Exercise Identity Scale for use with adults ages ≥55 years to measure regulatory styles and identity related to physical activity. Methods. Participants [Mage = 66.29 years (SD = 7.06)] answered an online questionnaire twice across a four-week timescale. We assessed measurement invariance and convergent and divergent validity based on relations between regulatory styles, identity, and physical activity. Results. Both measures were invariant across gender and time, and findings support the convergent and divergent validity of the scales. Notably, a two-factor model of identity representing role identity and physical activity beliefs provided the best fit, and physical activity beliefs was more strongly related to introjected regulation. Discussion. Taken together, there is evidence that these modified scales are suitable for use with adults ages ≥55 years.

Childhood Stressors, Relationship Quality, and Cognitive Health in Later Life.

OBJECTIVES: The rising prevalence of cognitive impairment, Alzheimer's disease, and related disorders signals the need for a better understanding of how social factors may affect cognitive health for millions of Americans. Drawing from cumulative inequality theory, we aim to understand the implications of a stressful childhood on social relationships and cognitive health in later life. METHODS: This study utilizes longitudinal data (2006-2016) from the Health and Retirement Study to examine pathways, both direct and indirect through social relationships in adulthood, from childhood stressors to cognitive health trajectories over time. RESULTS: Respondents reporting a greater number of stressors in childhood had worse cognitive health over time, but those negative effects were not as steep as time progressed. Early-life stressors are also associated with less social support and more social strain in adulthood which, in turn, are associated with initial cognitive health. Finally, pathway analyses confirm that childhood stressors are indirectly associated with initial cognitive health through social strain and social support. DISCUSSION: Findings reveal that a stressful childhood creates chains of risks that have lifelong implications for cognitive health, both directly and indirectly by creating obstacles for developing healthy and supportive social relationships.

Life Course Stressors and Functional Limitations in Later Life Among White, Black, and Hispanic Adults: Deleterious, Hardening, or Benign?

OBJECTIVES: Although striking racial and ethnic disparities in health are manifest during later life, they may be rooted in early-life exposures. Drawing from cumulative inequality theory, we investigate whether life course stressors are associated with the risk of later-life functional limitations and whether this relationship differs by race and ethnicity. METHODS: We utilize longitudinal data from the Health and Retirement Study to test whether child and adult stressors predict trajectories of the occurrence and severity of functional limitations among a diverse sample of older adults. RESULTS: Child and adult stressors are associated with greater occurrence and severity of functional limitations during later life. Mediation analyses reveal the indirect influence of child stressors via adult stressors on occurrence and severity of functional limitations; however, the indirect effects are slightly stronger for Black and Hispanic adults than their White counterparts. DISCUSSION: Child stressors, in and of themselves, do not increase functional limitations among Black and Hispanic people but are associated with greater adult stress exposure, predisposing them to more functional limitations. Results suggest that childhood stressors are associated with distinct social pathways to functional limitations among White, Black, and Hispanic older adults.

Do Early-Life Social, Behavioral, and Health Exposures Increase Later-Life Arthritis Incidence?

OBJECTIVES: This study investigates direct and indirect influences of childhood social, behavioral, and health exposures on later-life osteoarthritis and rheumatoid arthritis development. METHODS: Drawing from cumulative inequality theory and six waves of the Health and Retirement Study (2004-2014), we estimate structural equation modeling-based discrete-time survival analysis of the association between six childhood exposure domains and both osteoarthritis and rheumatoid arthritis incidence for men (n = 2720) and women (n = 2974). Using the delta method to test for mediation, we examine indirect effects via selected health-related risks and resources. RESULTS: Risky adolescent behavior is associated with rheumatoid arthritis incidence for women (h.O.R. = 1.883, 95% C.I. [1.016, 3.490]), whereas several types of childhood exposures are associated with later-life osteoarthritis development for both men and women. Experiencing two or more childhood socioeconomic disadvantages is indirectly associated with osteoarthritis (men: coef. = 0.024, 95% C.I. [0.003, 0.045]; women: coef. = 0.111, 95% C.I. [0.071, 0.150]) and rheumatoid arthritis (men: coef. = 0.037, 95% C.I. [0.000, 0.074]; women: coef. = 0.097, 95% C.I. [0.035, 0.159]) development through adult body mass index. DISCUSSION: Findings highlight the importance of childhood contexts in understanding the development of later-life osteoarthritis and rheumatoid arthritis.

Evaluating the Cumulative Impact of Childhood Misfortune: A Structural Equation Modeling Approach.

Most studies of the early origins of adult health rely on summing dichotomously measured negative exposures to measure childhood misfortune (CM), neglect, adversity, or trauma. There are several limitations to this approach, including that it assumes each exposure carries the same level of risk for a particular outcome. Further, it often leads researchers to dichotomize continuous measures for the sake of creating an additive variable from similar indicators. We propose an alternative approach within the structural equation modeling (SEM) framework that allows differential weighting of the negative exposures and can incorporate dichotomous and continuous observed variables as well as latent variables. Using the Health and Retirement Study data, our analyses compare the traditional approach (i.e., adding indicators) with alternative models and assess their prognostic validity on adult depressive symptoms. Results reveal that parameter estimates using the conventional model likely underestimate the effects of CM on adult health outcomes. Additionally, while the conventional approach inhibits testing for mediation, our model enables testing mediation of both individual CM variables and the cumulative variable. Further, we test whether cumulative CM is moderated by the accumulation of protective factors, which facilitates theoretical advances in life course and social inequality research. The approach presented here is one way to examine the cumulative effects of early exposures while attending to diversity in the types of exposures experienced. Using the SEM framework, this versatile approach could be used to model the accumulation of risk or reward in many other areas of sociology and the social sciences beyond health.

Early Origins of Body Mass in Later Life: Examining Childhood Risks and Adult Pathways.

Prior research reveals that negative early-life experiences play a major role in the development of obesity in later life, but few studies identify mechanisms that alter the lifetime risk of obesity. This study examines the influence of negative childhood experiences on body mass index (BMI) and obesity (BMI ≥30) during older adulthood and the psychosocial and behavioral pathways involved. Using a nationally representative sample, we examine the influence of cumulative misfortune as well as five separate domains of misfortune on BMI and obesity. Results show that four of the five domains are associated with BMI and obesity either directly, indirectly, or both. The influence of cumulative misfortune on the outcomes is mediated by three adult factors: socioeconomic status, depressive symptoms, and physical activity. The mediators identified here provide targets for intervention among older adults to help offset the health risks of excess BMI attributable of early-life exposure to misfortune.

Are Biological Consequences of Childhood Exposures Detectable in Telomere Length Decades Later?

Negative early-life exposures have been linked to a host of poor adult health outcomes, but are such early exposures associated with cellular senescence decades later? This study uses data from the Health and Retirement Study to examine the association between six childhood exposure domains (eg, socioeconomic disadvantage, risky parental behavior) and a biomarker of aging, telomere length, among 4,935 respondents. Telomere length is obtained from DNA of cells found in saliva and is measured as the telomere repeat copy number to single gene copy number ratio (T/S). Men who as children were exposed to risky parental behaviors or who reported risky adolescent behaviors have shorter telomeres (b = -0.031, p = .052; b = -0.041, p = .045, respectively); however, these relationships are attenuated after adjusting for adult risks and resources. Among women, parental substance abuse is associated with shorter telomeres even after adjusting for adult risks and resources (b = -0.041, p = .005). In addition, men and women whose mother lived at least until the age of 85 have longer telomeres than those without a long-lived mother (b = 0.021, p = .045; b = 0.032, p = .005, respectively). Taken together, the ways in which early-life exposures are associated with adult telomeres vary for men and women.

Questions to Measure Enjoyment of and Satisfaction With Physical Activity: Are They Appropriate for Use in an Older Population?

BACKGROUND AND OBJECTIVES: Enjoyment of and satisfaction with physical activity have been proposed as two actionable mechanisms to promote sustained engagement in physical activity. An accurate understanding of how, why, and for whom these two mechanisms work (or not) in response to a particular intervention strategy is contingent on having suitable measures for the population of interest. This study aims to determine whether the Physical Activity Enjoyment Scale-8 and a novel approach to the measurement of satisfaction with physical activity are suitable for use among older adults (M age = 66.25 years; range = 55-91 years). RESEARCH DESIGN AND METHODS: Participants answered an online questionnaire twice across 4 weeks. Measurement invariance was assessed within a structural equation modeling framework; convergent validity was assessed by correlating the latent variables enjoyment and satisfaction with each other and with physical activity behavior. RESULTS: Both measures were invariant between gender and across time. Enjoyment and satisfaction were related to each other (r = 0.72) and to physical activity (r = 0.48 and 0.64, respectively). DISCUSSION AND IMPLICATIONS: Results support the suitability of these measures as tools to assess enjoyment of and satisfaction with physical activity among older adults.

Digital technology use and depressive symptoms among older adults in Korea: beneficial for those who have fewer social interactions?

OBJECTIVES: Our study examines the relationship between digital technology use and depressive symptoms among older Koreans and whether social interaction moderates the relationship. METHODS: The data were drawn from the 2017 Survey of Living Conditions and Welfare Needs of Korean Older Persons, a nationally representative survey. Digital technology use was measured by the number of digital functions that respondents perform with their electronic devices. Social interactions were measured by the frequencies of face-to-face and remote connections with friends or neighbors. Relationships were estimated with multiple regression analyses. RESULTS: Digital technology use was inversely associated with depressive symptoms even after adjusting for covariates including cognitive function. Both remote and face-to-face connections with friends or neighbors were associated with fewer depressive symptoms. An interaction between digital technology use and remote contact also was detected: the effect of digital technology use on depressive symptoms was more beneficial for older adults with infrequent remote contact with friends or neighbors than for those with frequent remote contact. CONCLUSION: Findings suggest that digital technology use can reduce depressive symptoms of older adults, especially those who have fewer social interactions. Educating older adults to increase their digital literacy level and use of remote interactions may improve their psychological wellbeing, perhaps even during times of a viral pandemic.