Cohort Profile: the Health and Retirement Study (HRS)

Epigenome-wide association study of long-term psychosocial stress in older adults

Long-term psychosocial stress is strongly associated with negative physical and mental health outcomes, as well as adverse health behaviours; however, little is known about the role that stress plays on the epigenome. One proposed mechanism by which stress affects DNA methylation is through health behaviours. We conducted an epigenome-wide association study (EWAS) of cumulative psychosocial stress (n = 2,689) from the Health and Retirement Study (mean age = 70.4 years), assessing DNA methylation (Illumina Infinium HumanMethylationEPIC Beadchip) at 789,656 CpG sites. For identified CpG sites, we conducted a formal mediation analysis to examine whether smoking, alcohol use, physical activity, and body mass index (BMI) mediate the relationship between stress and DNA methylation. Nine CpG sites were associated with psychosocial stress (all p < 9E-07; FDR q < 0.10). Additionally, health behaviours and/or BMI mediated 9.4% to 21.8% of the relationship between stress and methylation at eight of the nine CpGs. Several of the identified CpGs were in or near genes associated with cardiometabolic traits, psychosocial disorders, inflammation, and smoking. These findings support our hypothesis that psychosocial stress is associated with DNA methylation across the epigenome. Furthermore, specific health behaviours mediate only a modest percentage of this relationship, providing evidence that other mechanisms may link stress and DNA methylation.

Hepatic WDR23 proteostasis mediates insulin homeostasis by regulating insulin-degrading enzyme capacity

Maintaining insulin homeostasis is critical for cellular and organismal metabolism. In the liver, insulin is degraded by the activity of the insulin-degrading enzyme (IDE). Here, we establish a hepatic regulatory axis for IDE through WDR23-proteostasis. Wdr23KO mice have increased IDE expression, reduced circulating insulin, and defective insulin responses. Genetically engineered human cell models lacking WDR23 also increase IDE expression and display dysregulated phosphorylation of insulin signaling cascade proteins, IRS-1, AKT2, MAPK, FoxO, and mTOR, similar to cells treated with insulin, which can be mitigated by chemical inhibition of IDE. Mechanistically, the cytoprotective transcription factor NRF2, a direct target of WDR23-Cul4 proteostasis, mediates the enhanced transcriptional expression of IDE when WDR23 is ablated. Moreover, an analysis of human genetic variation in WDR23 across a large naturally aging human cohort in the US Health and Retirement Study reveals a significant association of WDR23 with altered hemoglobin A1C (HbA1c) levels in older adults, supporting the use of WDR23 as a new molecular determinant of metabolic health in humans.

The Worst of Times: Depressive Symptoms Among Racialized Groups Living With Dementia and Cognitive Impairment During the COVID-19 Pandemic

Objective: To explore differences in depressive symptoms for older adults (Black, Latinx, and White) by cognitive status during the 2020 COVID-19 pandemic. Methods: Data from the Health and Retirement Study identified older adults as cognitively normal, cognitively impaired without dementia (CIND), and persons living with dementia (PLWD). Multiple linear regression analyses examined associations between cognitive status and depressive symptoms among these racialized groups. Results: Compared to the cognitively normal older adults racialized as Black, those with CIND reported higher depressive symptoms during the pandemic (overall and somatic) and PLWD had higher somatic symptoms (p < .01). Older adults racialized as White with CIND reported higher somatic (p < .01) symptoms compared to cognitively normal older adults racialized as White. Discussion: The COVID-19 pandemic was a challenging event among older adults racialized as Black with CIND and PLWD. Future studies should examine if these depressive symptoms persist over time.

A Visualization Tool to Study Dyadic Caregiving Health Profiles

OBJECTIVES

Guided by a life course perspective and fundamental cause theory, this study aims to visualize co-trajectories of health between partners and examine how changes in one spouse's cognitive status can cohesively impact the health of the other spouse along three dimensions (functional, mental, and cognitive).

METHODS

Drawing longitudinal data from the Health and Retirement Study 2000-2016 (N = 3582), we measure women's health profiles by functional limitation (physical health), depression (mental health), and cognitive function (cognitive health). We use multivariate linear mixed models to summarize these paths in the same visual representation.

RESULTS

The approach provides a visualization tool that depicts data and model in the same spatial representation allowing assessment of model fit and comparison. This study advances the traditional life course studies by representing underlying processes as a multidimensional time vector of health outcomes.

DISCUSSION

The described approach provides a blueprint for studying complex health profiles or trajectories.

Preclinical Dementia and Economic Well-Being Trajectories of Racially Diverse Older Adults

ObjectivesThis study examined the magnitude, changes, and racial/ethnic disparities in the economic costs of the 16-year preclinical phase of dementia-a period of cognitive decline without significant impact on daily activities. Methods: The study utilized two dementia algorithms to classify individuals with incident dementia in the Health and Retirement Study. These cases were compared to matched controls in terms of poverty status, labor force participation, and unsecured debts. Results: Older adults classified with dementia were more likely to drop out of the labor force and become poor than similar older adults without dementia. Racial/ethnic disparities in poverty persisted during the preclinical period, with non-Hispanic Black older adults more likely to leave the labor force and Hispanic older adults more likely to have unsecured debt. Discussion: Findings highlight the economic costs during prodromal phase of dementia, emphasizing need for early interventions to reduce financial strain across diverse older adults.

Cognition and Wealth Changes in Mid-to-later Life: A Latent Class Trajectories Approach Using the Health and Retirement Study

ObjectivesTo assess how cognitive trajectories from mid-to-later life relate to wealth change, overall and by mid-life income. Methods: Data were from participants (51-64 years) in the 2000-2018 U.S. Health and Retirement Study who were cognitively healthy at baseline (year 2000; unweighted n = 3821). Longitudinal latent class analyses generated cognitive and wealth trajectories, independently, and multinomial logistic regressions estimated the association between cognitive trajectories and wealth profiles, overall and by median income. Results: We identified three cognitive: cognitively healthy (CH), increasing cognitive impairment (ICI), and increasing dementia (ID) and four wealth profiles: stable wealth loss (SWL), delayed gradual wealth loss (DGWL), stable wealth gain (SWG), and gradual wealth gain (GWG). The ID group had higher probability of being in the SWL group and lower probability of SWG, which was more pronounced in respondents with greater median income. Discussion: Individuals with ID may be vulnerable to wealth loss, particularly for middle-class households.

The impact of social isolation on functional disability in older people: A multi-cohort study

OBJECTIVES

We assessed the relationship between social isolation and functional disability in older people.

DESIGN

Comparison of longitudinal cohort studies.

SETTING AND PARTICIPANTS

Harmonised longitudinal datasets from the United States, England, European countries, Japan, Korea, China and Hong Kong.

METHODS

Social isolation was operationalised as a composite score with five domains, such as marital status, living alone, and social contact with others. Functional disability was defined as whether the cohort participant had any difficulty in activities of daily living (ADL). In each dataset, we used robust Poisson regression models to obtain the relative risks (RRs) and the corresponding 95 % confidence intervals (CI). We combined the RRs to synthesize a pooled estimate using meta-analysis with random-effects models.

RESULTS

Overall, the social isolation composite score was not associated with ADL disability (pooled RR = 1.05, 95 % CI [0.97-1.14], n = 40,119). Subgroup analysis suggested social isolation composite score was associated with ADL disability in Asian regions (pooled RR = 1.09, 95 % CI [1.02, 1.16], but not in Western regions (pooled RR = 1.01, 95 % CI [0.96, 1.07]). The relationships between different domains of social isolation and ADL disability were heterogeneous, except that no participation in any social clubs or religious groups was consistently associated with ADL disability (pooled RR = 1.12, 95 % CI [1.04, 1.21]).

CONCLUSION

Targeting social isolation may prevent decline in functional abilities in older adults, providing an avenue to active and healthy ageing. Nonetheless, interventions tackling social isolation should tailor to the unique cultural and social underpinnings. A limitation of the study is that reverse causality could not be ruled out definitively.

Can you tell people's cognitive ability level from their response patterns in questionnaires?

Questionnaires are ever present in survey research. In this study, we examined whether an indirect indicator of general cognitive ability could be developed based on response patterns in questionnaires. We drew on two established phenomena characterizing connections between cognitive ability and people's performance on basic cognitive tasks, and examined whether they apply to questionnaires responses. (1) The worst performance rule (WPR) states that people's worst performance on multiple sequential tasks is more indicative of their cognitive ability than their average or best performance. (2) The task complexity hypothesis (TCH) suggests that relationships between cognitive ability and performance increase with task complexity. We conceptualized items of a questionnaire as a series of cognitively demanding tasks. A graded response model was used to estimate respondents' performance for each item based on the difference between the observed and model-predicted response ("response error" scores). Analyzing data from 102 items (21 questionnaires) collected from a large-scale nationally representative sample of people aged 50+ years, we found robust associations of cognitive ability with a person's largest but not with their smallest response error scores (supporting the WPR), and stronger associations of cognitive ability with response errors for more complex than for less complex questions (supporting the TCH). Results replicated across two independent samples and six assessment waves. A latent variable of response errors estimated for the most complex items correlated .50 with a latent cognitive ability factor, suggesting that response patterns can be utilized to extract a rough indicator of general cognitive ability in survey research.

The mutual longitudinal mediating effects of psychological and physical disorders on cognitive impairment among older adults

BACKGROUND

The potential mutual effect of physical and psychological disorders on cognitive function is critical for preventing cognitive impairment among older adults. We aimed to investigate the mediating role of physical and psychological disorders in their associations with cognitive function.

METHODS

We conducted a prospective cohort study using the Health and Retirement Study, involving 5308 adults aged 60 years or older. Physical disorders included seven self-reported physician-diagnosed conditions. Psychological disorder and cognitive function were ascertained using the 8-item Centers for Epidemiologic Research Depression scale and the 27-point HRS cognitive scale, respectively. Multivariable linear regression models were used to assess the association of the baseline scores of physical and psychological disorders with subsequent cognitive scores. Second-order cross-lagged panel models (CLPM) were used to assess the longitudinal mediating roles, respectively.

RESULTS

The higher psychological disorder scores (β = -0.15; P < 0.0001) and physical disorders scores (β = -0.18; P < 0.0001) were, the worse the cognitive function was. CLPM revealed a significant longitudinal mediating effect of baseline physical disorders through changes in psychological disorder from 2002 to 2010 on the cognitive scores changes from 2002 to 2010 (β = -0.02; P < 0.0001). Meanwhile, the longitudinal mediating effect of baseline psychological disorder scores through physical disorders changes from 2002 to 2010 on the cognitive scores changes from 2002 to 2010 was significant (β = -0.004; P = 0.005).

CONCLUSIONS

The mutual longitudinal mediating effects of psychological disorder and physical disorder indicate that among older adults, physical and psychological disorders accelerate cognitive impairment as a whole and mutually reinforcing process.

Views of aging and mental health - The role of informal care provision: Longitudinal findings of the health and retirement study in the US

BACKGROUND

Informal care is a common form of social support, which can vary greatly in its intensity. While views of aging have shown to be relevant to mental health before, we aim to analyze whether the association between views of aging and depressive symptoms is influenced by the provision of informal care and its intensity.

METHODS

Data of six waves of the Health and Retirement Study in the United States was used. The sample includes up to 41,058 observations pooled over six waves of community-dwelling adults aged ≥50 years. Depressive symptoms were measured with the Center for Epidemiologic Studies Depression Scale (CESD) and attitudes towards own aging (ATOA) with the Philadelphia Geriatric Center Morale Scale (higher score indicates positive attitudes); informal caregiving (no/yes) and caregiving intensity (moderate, intense) were surveyed. Adjusted fixed effects regression analysis with robust standard errors, and with caregiving as moderator variable were calculated.

RESULTS

Informal caregiving did not interact with ATOA. However, transitioning into intense caregiving significantly moderated the association between ATOA and depressive symptoms. Lower depressive symptoms were associated with better ATOA and this association was significantly stronger in the intense caregiving condition than in the non-caregiving condition. No significant interaction effects were found between any form of caregiving and subjective age.

LIMITATIONS

The possibility of reciprocal effects cannot be excluded.

CONCLUSION

Internalized ageism and depressive symptoms are more strongly related among caregivers who provide intense care. Thus, interventions to reduce internalized ageism could be helpful in particular among this vulnerable group of informal caregivers.

Association between internet exclusion and depressive symptoms among older adults: panel data analysis of five longitudinal cohort studies

Background

Internet exclusion and depressive symptoms are prevalent phenomena among older adults; however, the association between internet exclusion and depressive symptoms remains limited. This study aims to investigate the association between internet exclusion and depressive symptoms among older adults from high-income countries (HICs) and low- and middle-income countries (LMICs).

Methods

We conducted a comprehensive longitudinal, cross-cultural analysis, and the participants were adults aged 60 years and older from 32 countries participating in five nationally representative longitudinal cohort studies: the Health and Retirement Study (HRS), the English Longitudinal Study of Ageing (ELSA), the Survey of Health, Ageing and Retirement in Europe (SHARE), the China Health and Retirement Longitudinal Study (CHARLS), and the Mexican Health and Ageing Study (MHAS). Internet exclusion was defined as the self-reported absence from internet use. Depressive symptoms were evaluated using the Centre for Epidemiologic Studies of Depression scale (CES-D) or the Euro-Depression scale (Euro-D). These five cohorts, being heterogeneous, were respectively conducted with panel data analysis. Logistic regression, implemented within the generalized estimating equations framework, was used to examine the association between internet exclusion and the likelihood of experiencing depressive symptoms, adjusting for the causal-directed-acyclic-graph (DAG) minimal sufficient adjustment set (MSAS), including gender, age, education, labour force status, household wealth level, marital status, co-residence with children, residence status, cognitive impairment, and functional ability.

Findings

Our study included a total of 129,847 older adults during the period from 2010 to 2020, with a median follow-up of 5 (2, 7) years. The pooled proportion of internet exclusion was 46.0% in HRS, 32.6% in ELSA, 54.8% in SHARE, 92.3% in CHARLS, and 65.3% in MHAS. Internet exclusion was significantly associated with depressive symptoms across all cohort studies: HRS (OR = 1.13, 95% CI 1.07-1.20), ELSA (OR = 1.22, 95% CI 1.11-1.34), SHARE (OR = 1.55, 95% CI 1.47-1.62), CHARLS (OR = 1.49, 95% CI 1.26-1.77), and MHAS (OR = 1.48, 95% CI 1.39-1.58). Moreover, internet exclusion was found to be associated with all dimensions of depression in the SHARE, MHAS, and ELSA cohorts (except for sleep and felt sad) cohorts.

Interpretation

A considerable proportion of older adults experienced internet exclusion, particularly those in LMICs. Internet exclusion among older adults, irrespective of their geographic location in HICs or LMICs, was associated with a higher likelihood of experiencing depressive symptoms, which demonstrated the importance of addressing barriers to internet access and promoting active participation in the internet society among older adults.

Funding

National Key R&D Program of China (grant number 2022ZD0160704), the Scientific Research and Innovation Team of The First Affiliated Hospital of Zhengzhou University (grant number ZYCXTD2023005), the Collaborative Innovation Major Project of Zhengzhou (grant number 20XTZX08017), the Joint Project of Medical Science and Technology of Henan Province (grant number LHGJ20220428), and National Natural Science Foundation of China (grant number 82373341).

Animal Models Relevant for Geroscience: Current Trends and Future Perspectives in Biomarkers, and Measures of Biological Aging

For centuries, aging was considered inevitable and immutable. Geroscience provides the conceptual framework to shift this focus toward a new view that regards aging as an active biological process, and the biological age of an individual as a modifiable entity. Significant steps forward have been made toward the identification of biomarkers for and measures of biological age, yet knowledge gaps in geroscience are still numerous. Animal models of aging are the focus of this perspective, which discusses how experimental design can be optimized to inform and refine the development of translationally relevant measures and biomarkers of biological age. We provide recommendations to the field, including: the design of longitudinal studies in which subjects are deeply phenotyped via repeated multilevel behavioral/social/molecular assays; the need to consider sociobehavioral variables relevant for the species studied; and finally, the importance of assessing age of onset, severity of pathologies, and age-at-death. We highlight approaches to integrate biomarkers and measures of functional impairment using machine learning approaches designed to estimate biological age as well as to predict future health declines and mortality. We expect that advances in animal models of aging will be crucial for the future of translational geroscience but also for the next chapter of medicine.

Obesity, psychological well-being related measures, and risk of seven non-communicable diseases: evidence from longitudinal studies of UK and US older adults

BACKGROUND

We examined the role of psychological well-being related measures in explaining the associations between obesity and increased risk of non-communicable diseases (NCDs: hypertension, heart disease, stroke, diabetes, arthritis, cancer, and memory-related disease) in older adults.

METHODS

Data were from the English Longitudinal Study of Ageing (ELSA), UK (baseline: Wave 4-2008/2009; n = 8127) and the Health and Retirement Study (HRS), US (baseline: Waves 9 and 10-2008/2010; n = 12,477). Objective body mass index was used to define obesity. A range of psychological well-being related measures (e.g., depressive symptoms, life satisfaction) was available in ELSA (n = 7) and HRS (n = 15), and an index of overall psychological well-being was developed separately in each study. NCDs were from a self-reported doctor diagnosis and/or other assessments (e.g., biomarker data) in both studies; and in ELSA, NCDs from linked hospital admissions data were examined. Longitudinal associations between obesity status, psychological well-being measures, and NCDs were examined using Cox proportional hazard models (individual NCDs) and Poisson regression (a cumulative number of NCDs). Mediation by psychological well-being related measures was assessed using causal mediation analysis.

RESULTS

Obesity was consistently associated with an increased prospective risk of hypertension, heart disease, diabetes, arthritis, and a cumulative number of NCDs in both ELSA and HRS. Worse overall psychological well-being (index measure) and some individual psychological well-being related measures were associated with an increased prospective risk of heart disease, stroke, arthritis, memory-related disease, and a cumulative number of NCDs across studies. Findings from mediation analyses showed that neither the index of overall psychological well-being nor any individual psychological well-being related measures explained (mediated) why obesity increased the risk of developing NCDs in both studies.

CONCLUSION

Obesity and psychological well-being may independently and additively increase the risk of developing NCDs.

Sensory impairment, loneliness, and the discordance between subjective and objective cognitive function among older adults: A multi-cohort study

OBJECTIVES

This study aimed to examine the association between sensory impairment and the discordance between subjective/objective cognitive function among older adults and test the mediating effect of loneliness.

METHODS

We used data from four cohort studies conducted in 16 countries (N = 19,119). Sensory impairment and subjective cognitive impairment were self-reported. Objective cognitive impairment was measured in three dimensions. Generalized estimating equations were conducted to examine the association between sensory impairment and discordance in subjective/objective cognitive function. Cross-lagged panel model and a bootstrap method with 2,000 samples were employed to verify the mediating effect.

RESULTS

Sensory impairment was related to an increased risk of subjective cognitive impairment (OR = 4.70, 95 % CI 4.33-5.10), objective impairment (OR = 1.51, 95 %CI 1.31-1.74), as well as the discordance in subjective/objective cognitive function (OR = 1.35, 95 %CI 1.06-1.71 for older adults with normal subjective cognitive function). In contrast, sensory impairment was associated with a decreased risk of discordant subjective/objective cognitive function among those with subjective cognitive impairment (OR = 0.79, 95 %CI 0.66-0.94). Moreover, loneliness mediated the association between sensory impairment and subjective cognitive impairment (standardized indirect effect = 0.002, 95 %CI 0.001-0.004), objective cognitive impairment (standardized indirect effect = 0.005, 95 %CI 0.003-0.007) as well as the discordance in subjective/objective cognitive function (standardized indirect effect = 0.001, 95 %CI 0.001-0.003 for older adults with normal subjective cognitive function).

CONCLUSIONS

Significant association between sensory impairment and discordance in subjective/objective cognitive function and the mediating role of loneliness were revealed, varying by subjective cognitive function. Early screening on sensory impairment and targeted interventions on loneliness should be considered in future policies on cognitive impairment.

Education, gender, and frequent pain among middle-aged and older adults in the United States, England, China, and India

ABSTRACT

Using cross-sectional data from the United States, England, China, and India, we examined the relationship between education and frequent pain, alongside the modification role of gender in this relationship. We further examined patterns of 3 pain dimensions among participants who reported frequent pain, including pain severity, interference with daily activities, and medication use (these pain dimension questions were not administered in all countries). Our analytical sample included 92,204 participants aged 50 years and above. We found a high prevalence of frequent pain across the 4 countries ranging from 28% to 41%. Probit models showed that higher education was associated with lower risk of pain (United States: -0.26, 95% CI: -0.33, -0.19; England: -0.32, 95% CI: -0.39, -0.25; China: -0.33, 95% CI -0.41, -0.26; India: -0.18, 95% CI -0.21, -0.15). Notably, in China and India, the negative association between higher education and frequent pain was less pronounced among women compared with men, which was not observed in the United States or England. Further analysis showed that individuals with higher education experiencing frequent pain reported less severity, fewer daily activity interferences, and less medication use compared with those with lower education. In the United States, these associations were stronger among women. Our findings highlight the prevalent pain among middle-aged and older adults in these 4 countries and emphasize the potentially protective role of higher education on frequent pain, with nuanced gender differences across different settings. This underscores the need for tailored strategies considering educational and gender differences to improve pain management and awareness.

Exposures and conditions prior to age 16 are associated with dementia status among adults in the United States Health and Retirement Study

Background

Dementia susceptibility likely begins years before symptoms. Early life has not been comprehensively tested for dementia associations.

Method

In the US Health and Retirement Study (normal baseline cognition; n=16,509; 2008-2018 waves), 31 exposures before age 16 were retrospectively assessed with ten-year incident cognitive status (dementia, impaired, normal). Using parallel logistic models, each exposure was tested with incident cognition, adjusting for sex, baseline age, follow-up, race/ethnicity, personal/parental education.

Result

14.5% had incident impairment and 5.3% had dementia. Depression was associated with 1.71 (95%CI:1.28,2.26) times higher odds of incident impairment, relative to normal cognition. Headaches/migraines were associated with 1.63 (95%CI:1.18,2.22) times higher odds of incident impairment. Learning problems were associated with 1.75 (95%CI:1.05,2.79) times higher odds of incident impairment. Childhood self-rated health of fair (1.86, 95%CI:1.27,2.64) and poor (3.39, 95%CI:1.91,5.82) were associated with higher incident dementia odds, relative to excellent.

Conclusion

Early life factors may be important for impairment or dementia, extending the relevant risk window.

The longitudinal association between physical health and depressive symptoms over eight years: Evidence from the health and retirement study

BACKGROUND

The bidirectional relationship between physical health (PH) and depressive symptoms (DS) remains unclear.

METHODS

Data were extracted from the Health and Retirement Study in the United States. PH was measured with a composite of chronic diseases, functional limitations and difficulties in basic and instrumental activities of daily living, and DS with a modified Center for Epidemiological Studies of Depression. Latent growth curve models (LGCM) were employed to examine how the change in PH or DS affected their mutual trajectories in later life. In addition, multilevel models were utilized.

RESULTS

There were 6144 participants included, with an average age of 69.82 ± 6.85 years at baseline, of whom 3686 (59.99 %) were women. PH scores increased from 5.65 in 2010 to 7.72 in 2018, while depression scores increased from 1.14 to 1.31. LGCM results showed that the initial levels of PH and DS were associated (β = 0.558, P < .001), and the initial level of PH could predict the trajectory of DS (β = 0.089, P < .001). Likewise, the initial level of DS was also related to initial PH (β = -0.563, P < .001) but couldn't predict the trajectory of PH. Furthermore, the slopes of PH and DS were predicted bidirectionally by each other. Two-level logistic models further demonstrated the bidirectional association between PH and DS.

CONCLUSION

There was a bidirectional association between physical health and depressive symptoms, which highlights the necessity of comprehensive health management for older adults with poor physical health or depression symptoms.

Loneliness and low life satisfaction associated with older adults' poor oral health

Objective

To examine the association of older adults' loneliness, life satisfaction, and other psychological stressors and resources with oral health status.

Methods

This study merged 2018 data from the Health and Retirement Study (HRS) CORE survey with the HRS-Dental Module, and Psychosocial and Lifestyle Questionnaire-Panel A "Leave Behind" surveys (HRS-LB)(N = 418). Dental Module outcomes of interest were self-rated oral health status (SROH), and oral health-related quality of life (OHQOL). Older adults reported on loneliness, life satisfaction, perceived age, social status, control, mastery, and chronic stressors. Three distinct profiles based on the distribution of loneliness and life satisfaction were previously identified in the combined HRS and HRS-LB study population (N = 4,703) using latent class analysis (LCA). Class A:"Not Lonely/Satisfied" adults had the fewest psychosocial risk factors and most resources; Class C:"Lonely/Unsatisfied" adults exhibited the opposite profile (most risk factors, fewest resources); Class B:"Lonely/Satisfied" adults exhibited loneliness with favorable life satisfaction. Regression models examined associations between LCA classes and fair/poor SROH and the OHQOL scale score and individual items, after adjusting for socio-demographics.

Results

About 13% of older adults experienced loneliness, and about 16% reported low life satisfaction. About one-quarter (28%) of older adults reported fair/poor SROH, and they experienced more psychosocial risk factors than their counterparts with better oral health status. Nearly half the older adults were categorized in Class A:"Not Lonely/Satisfied" (n = 201), and about one-quarter each in Class B:"Lonely/Satisfied" (n = 103) and Class C:"Lonely/Unsatisfied" (n = 112). In fully adjusted models, Class B older adults had 1.81 (1.11-2.96) times greater odds of fair/poor SROH, and Class C had 4.64 (2.78-7.73) times greater odds of fair/poor SROH than Class A. Fully adjusted linear regression model results indicated a gradient by LCA class. OHQOL varied; Class A older adults had the best (lowest) OHQOL score (mean = 8.22, 4.37-12.10), Class B scored in the middle (mean = 12.00, 7.61-16.50), while Class C had the worst (highest) OHQOL score (mean = 16.20, 11.80-20.60).

Conclusion

Loneliness, as a defining characteristic distinguishing three latent classes of older adults, was associated with more risk factors and poorer oral health outcomes. Loneliness, life satisfaction, perceived age, social status, control, mastery, and chronic stressors vary widely for older adults and matter for oral health and OHQOL.

Trajectories of pain and their associations with long-term cognitive decline in older adults: evidence from two longitudinal cohorts

BACKGROUND

Pain is a dynamic experience that varies over time, but it remains unknown whether trajectories of pain are associated with subsequent cognitive decline. The purpose of this study was to identify distinct trajectories of pain presence and activity-limiting pain and investigate their longitudinal associations with the rate of subsequent cognitive decline in older adults.

METHODS

A total of 5685 participants from the English Longitudinal Study of Ageing (ELSA) and 7619 participants from the Health and Retirement Study (HRS) were included. Pain presence trajectories were identified over eight years in the ELSA and 10 years in the HRS, while trajectories of activity-limiting pain were identified over 10 years in the HRS. We utilised linear mixed-effects models to investigate the long-term relationship between pain trajectories and the rate of cognitive decline across various domains, including memory, orientation, executive function and global cognition.

RESULTS

Three pain presence trajectories were identified. Moderate-increasing and high-stable groups exhibited steeper declines in global cognition than the low-stable group. Furthermore, individuals in the moderate-increasing group experienced a more rapid decline in executive function, while the high-stable group showed a faster decline in orientation function. Two trajectories of activity-limiting pain were identified, with the moderate-increasing group experiencing a faster decline in orientation function and global cognition.

CONCLUSIONS

The trajectories of both pain presence and activity-limiting pain are linked to the rate of subsequent cognitive decline among older people. Interventions for specific pain trajectories might help to delay the decline rate of cognition in specific domains.

Association between days spent at home and functional status and health among persons living with dementia

BACKGROUND

Many persons living with dementias (PLWD) prefer to remain at home as long as possible, and days spent at home (DAH)-defined as the time an individual spends outside of healthcare facilities-has emerged as a person-centred outcome measure in this population. We examined the association between DAH and functional status and health among PLWD.

METHODS

Utilizing a nationally representative cohort of individuals age 65 and older in the United States with dementia from the 2010-2018 Health and Retirement Study (HRS), we assessed the relationship between an ordinal categorical DAH variable and number of activities of daily living (ADLs) (range 0-10; 10 being independent), mobility (0-5; 5 being mobile), and self-rated health (SRH) (0-4; 4 being excellent), controlling for patient characteristics. DAH was defined as the number of self-reported days spent outside a hospital or nursing home in the time between survey waves, typically 730 days.

RESULTS

We identified 3002 participants (4192 observations, average 1.4 observations per participant). The mean DAH was 704.4 days (SD 10.8 days) and 64.9% spent all days at home (i.e. 730 days). A 2-week decrease in DAH was associated with a lower ADL score by 0.32 points (95% confidence internal [CI]: 0.24-0.40, P-for-trend<0.001), a lower mobility score by 0.18 points (95% CI: 0.13-0.22, P-for-trend<0.001), and a lower SRH by 0.05 points (95% CI: 0.02-0.08, P-for-trend<0.001).

CONCLUSION

We demonstrate that DAH is positively associated with important patient-reported outcomes among the dementia population, strengthening the argument for considering DAH as a meaningful outcome measure for PLWD.

Development and assessment of analytic methods to improve the measurement of cognition in longitudinal studies of aging through the use of substudies with comprehensive neuropsychological testing

INTRODUCTION

The Health and Retirement Study International Partner Surveys (HRS IPS) have rich longitudinal data, but the brevity of cognitive batteries is a limitation.

METHODS

We used data from a substudy of the English Longitudinal Study of Ageing (ELSA) administering detailed cognitive assessments with the Harmonized Cognitive Assessment Protocol (ELSA-HCAP) (N = 1273) to inform approaches for estimating cognition in ELSA (N = 11,213). We compared two novel approaches: confirmatory factor analysis (CFA)- and regression-based prediction.

RESULTS

Compared to estimates from the full HCAP battery, estimated cognitive functioning derived using regression models or CFA had high correlations (regression: r = 0.85 [95% confidence interval [CI]: 0.83 to 0.87]; CFA: r = 0.83 [95% CI: 0.81 to 0.85]) and reasonable mean squared error (regression: 0.25 [0.22 to 0.27]; CFA: 0.29 [0.26 to 0.32]) in held-out data. The use of additional items from waves 7 to 9 improved performance.

DISCUSSION

Both approaches are recommended for future research; the similarity in approaches may be due to the brevity of available cognitive assessments in ELSA.

HIGHLIGHTS

Estimates of cognitive functioning informed by English Longitudinal Study of Ageing-Harmonized Cognitive Assessment Protocol (ELSA-HCAP) data had an adequate performance. Standard errors were smaller for associations with example risks when using measures informed by ELSA-HCAP. Performance was better when including additional cognitive measures available in waves 7 to 9. Conceptual advantages to the confirmatory factor analysis (CFA) approach were not important in practice due to the brevity of the ELSA cognitive battery.

Costs of Forced Retirement: Measuring the Effect of Lost Work Opportunity on Health

OBJECTIVE

Unemployment is a known health stressor that also increases early retirements. This study addresses mixed literature on retiree health and underreporting of forced retirement to better identify potential health impacts of lost work opportunity.

METHODS

A Lost-work Opportunity Score (LOS) was created using variables from the Health and Retirement Study assessing unemployment, forced retirement, and earlier-than-planned retirement for 2576 respondents. Reliability and unidimensionality of the score with multivariate regression analyses examined health impacts controlling for demographics and prior health status.

RESULTS

The LOS possessed unidimensionality with a Cronbach's alpha of a = 0.76 while predicting self-reported health declines (LOS = 2; β = 0.381, OR = 1.464, P < 0.05) and depression increase (LOS = 2; β = 0.417, OR = 1.517, P < 0.05).

CONCLUSIONS

LOS predicts 46% increased odds of negative self-reported health change after retirement associated with two LOS events, with implications to support aging workers.

The psychological burden associated with metabolic syndrome: Evidence from UK and US older adults

Introduction

We examined the psychological burden associated with metabolic syndrome (MetSyn).

Methods

We used comparable longitudinal data of older adults (≥50 years) from the UK (English Longitudinal Study of Aging) and the US (Health and Retirement Study). We defined MetSyn based on biomarker assessments (e.g., blood pressure, impaired glycemic control). Using regression models, we tested a range of individual psychological outcomes (e.g., depressive symptoms) associated with MetSyn. We also examined whether these psychological outcomes may explain or moderate the link between MetSyn and non-communicable diseases (NCDs).

Findings

MetSyn was associated cross-sectionally with a range of psychological outcomes, including depression, anxiety, loneliness, hopelessness, cynical hostility, social strain, negative affect and decreased positive affect, social support and purpose in life. There was no convincing evidence that psychological factors interacted with or explained (mediated) the relationship between MetSyn and increased risk of developing NCD over 10-year follow-ups.

Conclusions

MetSyn and the psychological burden outcomes examined may have independent effects on NCD risk.

Bridge Employment or Encore Career? Examining Predictors That Distinguish Later-Life Career Transitions

OBJECTIVES

Bridge employment and encore careers are 2 prevalent retirement pathways that have different goals and outcomes. Yet, "changing jobs in later life" is the shared prequel that blurs the distinction between them in empirical studies. This study proposes a set of criteria-voluntariness of career transition and the duration of work in the posttransition job-to distinguish various retirement pathways and investigates the predictors that distinguish the workers' choice of these pathways.

METHODS

I conducted multinomial logistic regression to examine the predictors that distinguish between bridge employment, encore career, and direct workforce exit using the longitudinal sample of respondents with full-time career jobs in the Health and Retirement Study 1992-2020 (HRS, N = 2,038). To examine the predictors that distinguish between bridge employment and encore careers, I conducted logistic regression on the subsample of respondents who chose either bridge employment or encore careers (n = 927).

RESULTS

The results show that the accumulated human capital from career jobs, physical and mental health conditions before leaving career jobs, and self-identified retirement status when transitioning to new jobs distinguish the workers' choices of taking on different retirement pathways.

DISCUSSION

Maintaining the labor force participation of older workers is an important human resource agenda for policymakers. This study suggests that increasing the number of quality jobs for older workers would promote bridge employment and encore careers by raising the benefits of making career transitions as well as improving older workers' health.

Inequalities in accelerated cognitive decline: Resolving observational window bias using nested non-linear regression

INTRODUCTION

Limited observational windows lead to conflicting results in studies examining educational differences in Alzheimer's disease and related dementias (ADRD) risk, due to observational window bias relative to onset of accelerated cognitive decline. This study tested a novel model to address observational window bias and tested for the presence and sources of disparities in accelerated cognitive declines due to ADRD.

METHODS

The sample examined 167,314 cognitive assessments from 32,441 Health and Retirement Study participants. We implemented a parametric non-linear nested longitudinal regression and reported multivariable-adjusted nodal incidence ratios (aNIR).

RESULTS

University degrees were associated with lower incidence (aNIR = 0.253, 95% confidence interval [CI] = [0.221 to 0.289], p < 0.001), while black participants had a higher incidence (aNIR = 1.995, [1.858 to 2.141], p < 0.001) of accelerated cognitive decline, adjusting for demographic, sociobehavioral, and medical risk factors. Sex-stratified analyses identified diminished educational returns for women and increased incidence among minoritized women.

DISCUSSION

Addressing observational window bias reveals large social inequalities in the onset of accelerated cognitive declines indicative of ADRD.

HIGHLIGHTS

This study identifies observational window bias as a source of conflicting results among previous studies of educational achievement in Alzheimer's disease and related dementias (ADRD) disparities. The study locates preclinical accelerated cognitive decline, which is indicative of ADRD while occurring 10+ years prior to symptom onset, as a site to study ADRD disparities that mitigates observational window bias. A novel method, nested non-linear regression, is developed to test for differences in the onset of accelerated cognitive decline. Educational and racial/ethnic disparities are demonstrated in the onset of accelerated cognitive decline, as are their intersecting differences with sex/gender.

Factors Associated With Psychological Wellbeing in Home Care Older Adults With Alzheimer's Disease: A Longitudinal Analysis

The long-term symptoms associated with Alzheimer's disease pose significant challenges to the psychological wellbeing of patients. This longitudinal study aims to analyze the effects of socioeconomic factors and physical health factors on the psychological wellbeing of older patients diagnosed with Alzheimer's disease (AD) receiving home care, as well as the moderating role of aging and care support in influencing their psychological wellbeing. Data from the Health and Retirement Study (N = 628 older Alzheimer's patients) were analyzed using pooled ordinary least squares fixed-effects models. Findings suggest that Alzheimer's patients' psychological wellbeing was significantly affected by factors including cohabitation, gender, assistance frequency, age, education, and daily activity challenges, with assistance and increasing age mitigating some daily difficulties. The findings underline the multifactorial nature of psychological wellbeing among older Alzheimer's patients in home care and the critical role of social and physical health determinants in shaping these outcomes.

Sex differences in association of joint glycemic, blood pressure and lipid control and two-year risk of falls among older adults with diabetes

AIMS

To characterize the risk of falls among males and females by joint glycemic, blood pressure (BP) and cholesterol control among older adults (≥65 years) with diagnosed diabetes in USA.

METHODS

Using longitudinal data from the Health and Retirement Study (2006-2019), we studied the association of joint glycemic (HbA1c < 7.5 %), BP (systolic <140 and diastolic <90 mmHg) and cholesterol (total < 200 mg/dL) control with two-year risk of falls. We estimated risk ratios (RR) to describe the associations for joint ABC control and independent biomarker control by sex, using modified Poisson regressions after adjusting for known individual and household risk factors.

RESULTS

The analytic sample consisted of 4509 observations from 2829 older adults (54.7 % female) with a mean age of 72.2 (SD: 6.6) years and duration of diabetes of 9.9 years. Joint ABC control was not associated with risk of falls among females but was associated with lower risk among males (0.91 [95%CI: 0.81-1.02]). Furthermore, achievement of glycemic control (0.85 [95%CI: 0.73-0.98]) and BP control (0.89 [95%CI: 0.79-1.01]) were associated with lower risk but cholesterol control (1.15 [95%CI: 0.99, 1.34]) was associated with higher risk of falls among males.

CONCLUSIONS

Joint achievement of glycemic, BP and cholesterol targets may prevent falls among older males. Future studies among people with diabetes should consider biomarker control as a preventive factor for falls.

Associations between socioeconomic inequalities and progression to psychological and cognitive multimorbidities after onset of a physical condition: a multicohort study

Background

Chronic physical conditions (e.g., heart diseases, diabetes) increase with population ageing, contributing to psychological and cognitive multimorbidities. Yet, little is known about socioeconomic inequalities in this process. We examined the associations between socioeconomic status (SES) and progression to psychological and cognitive multimorbidities after onset of a physical condition.

Methods

We used harmonized individual-level data from five prospective cohort studies across 24 countries in the US, Europe and Asia, with repeated morbidity measurements between 2002 and 2021. Participants with at least one new-onset physical conditions (hypertension, diabetes, heart diseases, stroke, chronic lung diseases, cancer, or arthritis) were followed up for progression to physical-psychological multimorbidity, physical-cognitive multimorbidity, and physical-psychological-cognitive multimorbidity. SES was determined based on educational level and total household wealth at the onset of a physical condition. Time to and incidence rates of progressing psychological and cognitive multimorbidities were estimated in analyses stratified by SES. Fine-Gray subdistribution hazard models and multi-state models were used to estimate the associations between SES and progression to psychological and cognitive multimorbidities.

Findings

Among 20,250 participants aged ≥45 years (mean age at a physical condition onset 65.38 years, standard deviation 8.37) with at least one new-onset physical conditions in the analysis, 7928 (39.2%) progressed to psychological and cognitive multimorbidities during a median follow-up of 8.0 years (168,575 person-years). The mean survival time free from physical-psychological-cognitive multimorbidity was 11.96 years (95% confidence interval 11.57-12.34) in low SES individuals, compared to 15.52 years (15.40-15.63) in high SES individuals, with the corresponding incidence rate of 18.44 (16.32-20.82) and 3.15 (2.48-4.01) per 1000 person-years, respectively. The associations of education, household wealth and SES with multimorbidities followed a dose-dependent relation, with subdistribution hazard ratios per decreasing SES category being 1.24 (1.19-1.29) for physical-psychological multimorbidity, 1.47 (1.40-1.54) for physical-cognitive multimorbidity, and 1.84 (1.72-1.97) for physical-psychological-cognitive multimorbidity. The strongest SES-multimorbidities associations were observed in participants with arthritis, hypertension or diabetes. In multi-state models SES was linked to all five transitions from physical condition to physical-psychological multimorbidity, physical-cognitive multimorbidity and physical-psychological-cognitive multimorbidity.

Interpretation

Socioeconomic inequalities are associated with the progression of a chronic physical condition, with the lower SES groups had both an earlier time to and a higher incidence of psychological and cognitive multimorbidities. These findings underscore the need for more effective equity-oriented policies and healthcare practices to address reduced psychological wellness and cognitive maintenance among individuals with low SES and physical conditions.

Funding

Zhejiang University Hundred Talents Program Research Initiation Fund, Fundamental Research Funds for the Central Universities in China, Wellcome Trust, Medical Research Council, National Institute on Aging, Academy of Finland.

Early-Life Circumstances and Racial Disparities in Cognition Among Older Adults in the US

Importance

Given the critical role of neurocognitive development in early life, understanding the association between early-life circumstances and racial disparities in cognition has important implications.

Objective

To assess whether racial differences in early-life circumstances are collectively and individually associated with racial disparities in late-life cognition among older adults in the US.

Design, Setting, and Participants

This cross-sectional study used comprehensive life history data from the Health and Retirement Study, a nationally representative survey of US adults 50 years or older. Data analyses were performed from August 9, 2022, to January 20, 2024.

Main Outcomes and Measures

Racial differences in early-life circumstances and racial disparities in late-life cognition were investigated using a Blinder-Oaxaca decomposition regression model. Cognitive outcomes, including cognitive score and cognitive impairment, were evaluated using the Telephone Interview for Cognitive Status. Early-life educational experiences were primary explanatory variables; early-life cohort, regional, financial, health, trauma, family relationship factors, and educational attainment were additional explanatory variables; demographic and genetic factors were covariates.

Results

The study sample comprised 9015 participants; 1634 non-Hispanic Black (hereafter, Black) individuals (18.1%) and 7381 non-Hispanic White (hereafter, White) individuals (81.9%). Among Black participants, the mean (SD) age was 69.2 (9.2) years and 1094 (67.0%) were women. Among White participants, the mean (SD) age was 73.2 (10.1) years and 4410 (59.7%) were women. Cognitive scores (scale, 0-27) were significantly lower among Black participants (13.5 [95% CI, 13.3-13.7] points) than among White participants (15.8 [95% CI, 15.7-15.9] points), while the prevalence of cognitive impairment (cognitive score <12) was significantly higher among Black participants (33.6 [95% CI, 31.3-35.9] percentage points [ppt]) than among White participants (16.4 [95% CI, 15.6-17.2] ppt). Substantial racial differences were observed in early-life circumstances. Overall, differences in early-life circumstances were associated with 61.5% of the racial disparities in cognitive score (1.4 [95% CI, 0.88-2.0] points), and 82.3% of the racial disparities in cognitive impairment (14.2 [95% CI, 8.8-19.5] ppt), respectively. In multivariable analyses, early-life educational experiences were associated with 35.2% of the disparities in cognitive score and 48.6% in cognitive impairment. Notably, school racial segregation (all segregated schooling before college) was associated with 28.8% to 39.7% of the racial disparities in cognition. These findings were consistent in a series of sensitivity analyses.

Conclusions and Relevance

The findings of this cross-sectional study suggest that less favorable early-life circumstances are associated with clinically meaningful racial disparities in late-life cognition. Policies that improve educational equity have the potential to reduce racial disparities in cognition in older ages. Clinicians may leverage early-life circumstances to promote the screening, prevention, and interventions of cognitive impairment more efficiently, thereby promoting health equity.

Joint daily functional trajectory and risk of new-onset Alzheimer's disease and related dementias in older adults with normal and abnormal weight

BACKGROUND

Associations between daily functional trajectories and new-onset all-cause dementia and Alzheimer's disease (AD) and the role of body weight are underexplored.

METHODS

Data were from the Health and Retirement Study (HRS) 1994-2020. Daily function was assessed using (instrumental) activities of daily living ([I]ADLs). All-cause dementia and AD were defined by self- or proxy-reported physician diagnoses. Body weight was assessed using body mass index (BMI) and categorized as normal (18.5 kg/m2 ≤ BMI < 30 kg/m2) and abnormal (BMI < 18.5 kg/m2 or ≥30 kg/m2). The group-based trajectory modeling and Cox proportional hazards regression were utilized.

RESULTS

Of 18,763 adults included, 1236 developed new-onset dementia during a 10-year follow-up. The associations of ADL and IADL limitations at baseline with all-cause dementia and AD were much more pronounced in those with abnormal weight (P for interaction < 0.005). Five joint trajectories of ADL and IADL limitations were identified: No (72.7 %), Recovery (4.0 %), Recent emerging (16.4 %), Early emerging (4.8 %), and Severe (2.1 %). Furthermore, the 'Severe' joint trajectory (vs. 'No') was associated with 3.57- and 3.59-times higher risks of new-onset all-cause dementia and AD in participants with abnormal weight (P for interaction = 0.002 and 0.005). Notably, the Recovery joint trajectory (vs. No) was not associated with increased risks of all-cause dementia or AD.

LIMITATIONS

Self-/proxy-reported all-cause dementia and AD may introduce misclassification bias. Lifestyle factors were not quantified. BMI at baseline, but not its trajectory, was utilized. Potential reverse causation deserved attention.

CONCLUSIONS

Body weight control can help reduce the risk of progression from functional limitations to all-cause dementia and AD.

Achieving goal-concordant care: Formal and informal advance care planning for White, Black, and Hispanic older adults

INTRODUCTION

Advance care planning (ACP) aims to ensure that patients receive goal-concordant care (GCC), which is especially important for racially or ethnically minoritized populations at greater risk of poor end-of-life outcomes. However, few studies have evaluated the impact of advance directives (i.e., formal ACP) or goals-of-care conversations (i.e., informal ACP) on such care. This study aimed to examine the relationship between each of formal and informal ACP and goal-concordant end-of-life care among older Americans and to determine whether their impact differed between individuals identified as White, Black, or Hispanic.

METHODS

We conducted a retrospective cohort study using 2012-2018 data from the biennial Health and Retirement Study. We examined the relationships of interest using two, separate multivariable logistic regression models. Model 1 regressed a proxy report of GCC on formal and informal ACP and sociodemographic and health-related covariates. Model 2 added interaction terms between race/ethnicity and the two types of ACP.

RESULTS

Our sample included 2048 older adults. There were differences in the proportions of White, Black, and Hispanic decedents who received GCC (83.1%, 75.3%, and 71.3%, respectively, p < 0.001) and in the use of each type of ACP by racial/ethnic group. In model 1, informal compared with no informal ACP was associated with higher odds of GCC (adjusted odds ratio = 1.38 [95% confidence interval, 1.05-1.82]). In model 2, Black decedents who had formal ACP were more likely to receive GCC than those who did not, but there were no statistically significant differences between decedents of different racial/ethnic groups who had no ACP, informal ACP only, or both types of ACP.

CONCLUSIONS

Our results build on previous work by indicating the importance of incorporating goals-of-care conversations into routine healthcare for older adults and encouraging ACP usage among racially and ethnically minoritized populations who use ACP tools at lower rates.

The association of pre-cancer diagnosis cardiovascular risk factors with memory aging after a cancer diagnosis, overall and by race/ethnicity

PURPOSE

Cardiovascular risk factors (CVRFs) are associated with increased risk for cognitive impairment and decline in the general population, but less is known about how CVRFs might influence cognitive aging among older cancer survivors. We aimed to determine how CVRFs prior to a cancer diagnosis affect post-cancer diagnosis memory aging, compared to cancer-free adults, and by race/ethnicity.

METHODS

Incident cancer diagnoses and memory (immediate and delayed recall) were assessed biennially in the US Health and Retirement Study (N = 5,736, 1998-2018). CVRFs measured at the wave prior to a cancer diagnosis included self-reported cigarette smoking, obesity, diabetes, heart disease, hypertension, and stroke. Multivariable-adjusted linear mixed-effects models evaluated the rate of change in standardized memory score (SD/decade) post-cancer diagnosis for those with no, medium, and high CVRFs, compared to matched cancer-free adults, overall and stratified by sex and race/ethnicity.

RESULTS

Higher number of CVRFs was associated with worse baseline memory for both men and women, regardless of cancer status. Cancer survivors with medium CVRFs had slightly slower rates of memory decline over time relative to cancer-free participants (0.04 SD units/decade [95% CI: 0.001, 0.08]). Non-Hispanic Black (NHB) and Hispanic cancer-free participants and cancer survivors had worse baseline memory than their Non-Hispanic White (NHW) counterparts.

CONCLUSIONS

CVRFs were associated with worse baseline memory function, but not decline, for cancer-free adults and cancer survivors. Racial disparities were largely similar between cancer survivors and cancer-free adults.

IMPLICATIONS FOR CANCER SURVIVORS

These findings may inform hypotheses about pre-diagnosis multimorbidity and cognitive aging of cancer survivors from diverse groups.

DNA Methylation at C-Reactive Protein-Associated CpG Sites May Mediate the Pathway Between Educational Attainment and Cognition

Growing evidence has linked inflammatory processes to cognitive decline and dementia. This work examines whether an epigenetic marker of C-reactive protein (CRP), a common clinical inflammatory biomarker, may mediate the relationship between educational attainment and cognition. We first evaluated whether 53 previously reported CRP-associated DNA methylation sites (CpGs) are associated with CRP, both individually and aggregated into a methylation risk score (MRSCRP), in 3 298 participants from the Health and Retirement Study (HRS, mean age = 69.7 years). Forty-nine CpGs (92%) were associated with the natural logarithm of CRP in HRS after adjusting for age, sex, smoking, BMI, genetic ancestry, and white blood cell counts (p < .05), and each standard deviation increase in MRSCRP was associated with a 0.38 unit increase in lnCRP (p = 4.02E-99). In cross-sectional analysis, for each standard deviation increase in MRSCRP, total memory score and total cognitive score decreased, on average, by 0.28 words and 0.43 items, respectively (p < .001). Further, MRSCRP mediated 6.9% of the relationship between high school education and total memory score in a model adjusting for age, sex, and genetic ancestry (p < .05); this was attenuated to 2.4% with additional adjustment for marital status, APOE ε4 status, health behaviors, and comorbidities (p < .05). Thus, CRP-associated methylation may partially mediate the relationship between education and cognition at older ages. Further research is warranted to determine whether DNA methylation at these sites may improve current prediction models for cognitive impairment in older adults.

Inequalities in Disability-Free and Disabling Multimorbid Life Expectancy in Costa Rica, Mexico, and the United States

OBJECTIVES

To better understand variations in multimorbidity severity over time, we estimate disability-free and disabling multimorbid life expectancy (MMLE), comparing Costa Rica, Mexico, and the United States (US). We also assess MMLE inequalities by sex and education.

METHODS

Data come from the Costa Rican Study on Longevity and Healthy Aging (2005-2009), the Mexican Health and Aging Study (2012-2018), and the Health and Retirement Study (2004-2018). We apply an incidence-based multistate Markov approach to estimate disability-free and disabling MMLE and stratify models by sex and education to study within-country heterogeneity. Multimorbidity is defined as a count of 2 or more chronic diseases. Disability is defined using limitations in activities of daily living.

RESULTS

Costa Ricans have the lowest MMLE, followed by Mexicans, then individuals from the US. Individuals from the US spend about twice as long with disability-free multimorbidity compared with individuals from Costa Rica or Mexico. Females generally have longer MMLE than males, with particularly stark differences in disabling MMLE. In the US, higher education was associated with longer disability-free MMLE and shorter disabling MMLE. We identified evidence for cumulative disadvantage in Mexico and the US, where sex differences in MMLE were larger among the lower educated.

DISCUSSION

Substantial sex and educational inequalities in MMLE exist within and between these countries. Estimating disability-free and disabling MMLE reveals another layer of health inequality not captured when examining disability and multimorbidity separately. MMLE is a flexible population health measure that can be used to better understand the aging process across contexts.

Cohort Differences in Physical Health and Disability in the United States and Europe

OBJECTIVES

Declines in mortality have historically been associated with improvements in physical health across generations. While life expectancy in most high-income countries continues to increase, there is evidence that younger generations, particularly in the United States, are less healthy than previous generations at the same age. We compared generational trends in physical health in the United States, England, and continental Europe to explore whether other regions have experienced a similar pattern of worsening health across cohorts.

METHODS

Using data from nationally representative studies of adults aged ≥50 years from the United States (Health and Retirement Study, n = 26,939), England (English Longitudinal Study of Ageing, n = 14,992) and 11 continental European countries (Survey of Health, Ageing and Retirement in Europe, n = 72,595), we estimated differences in the age-adjusted prevalence of self-reported chronic disease and disability and observer-measured health indicators across pseudo-birth cohorts (born <1925, 1925-1935, 1936-1945, 1946-1954, 1955-1959).

RESULTS

Age-adjusted prevalence of doctor-diagnosed chronic disease increased across successive cohorts in all regions. Trends in disability prevalence were more regionally varied. Still, in both the United States and Europe, we observed a structural break in disability trends, with declines observed in prewar cohorts slowing, stalling, or reversing for cohorts born since 1945.

DISCUSSION

In all regions, we found evidence for worsening health across cohorts, particularly for those born since 1945. While more chronic disease in younger cohorts need not necessarily translate to worse quality of life or higher rates of functional limitation, there is some suggestion that worsening chronic disease morbidity may be spilling over into worsening disability.

Informal Helping and Subsequent Health and Well-Being in Older U.S. Adults

BACKGROUND

Growing evidence suggests that informal helping (unpaid volunteering not coordinated by an organization or institution) is associated with improved health and well-being outcomes. However, studies have not investigated whether changes in informal helping are associated with subsequent health and well-being.

METHODS

This study evaluated if changes in informal helping (between t0;2006/2008 and t1;2010/2012) were associated with 35 indicators of physical, behavioral, and psychosocial health and well-being (at t2;2014/2016) using data from 12,998 participants in the Health and Retirement study - a national cohort of US adults aged > 50.

RESULTS

Over the four-year follow-up period, informal helping ≥ 100 (versus 0) hours/year was associated with a 32% lower mortality risk (95% CI [0.54, 0.86]), and improved physical health (e.g., 20% reduced risk of stroke (95% CI [0.65, 0.98])), health behaviors (e.g., 11% increased likelihood of frequent physical activity (95% CI [1.04, 1.20])), and psychosocial outcomes (e.g., higher purpose in life (β = 0.15, 95% CI [0.07, 0.22])). However, there was little evidence of associations with various other outcomes. In secondary analyses, this study adjusted for formal volunteering and a variety of social factors (e.g., social network factors, receiving social support, and social participation) and results were largely unchanged.

CONCLUSIONS

Encouraging informal helping may improve various aspects of individuals' health and well-being and also promote societal well-being.

DNA Methylation Mediates the Association Between Cardiometabolic Risk Factors and Cognition: Findings From the Health and Retirement Study

The association between cardiometabolic risk factors and cognitive function has been well documented, but the underlying mechanisms are not fully understood. This longitudinal study aimed to investigate the potential mediating role of DNA methylation in this association. We conducted the analyses in 3 708 participants (mean [standard deviation {SD}] age: 67.3 [9.5], women: 57.9%) from the Health and Retirement Study who were assessed in the 2014-2020 waves, had Infinium Methylation EPIC BeadChip methylation assays from the 2016 Venous Blood Study, and had cognitive assessment between 2016 and 2020. Causal mediation analyses were used to test the mediation role of DNA methylation in the associations between cardiometabolic risk factors and cognition, adjusting for demographic, socioeconomic, and lifestyle factors. Hypertension (-0.061 in composite cognitive z-score; 95% confidence interval [CI: -0.119, -0.004]) and diabetes (-0.134; 95% CI: [-0.198, -0.071]) were significantly associated with worse cognitive function while abnormal body weight and hypercholesterolemia were not. An increased number of cardiometabolic risk factors was associated with worse cognitive function (p = .002). DNA methylation significantly mediated the association of hypertension (mediated effect on composite cognitive z-score: -0.023; 95% CI: -0.033, -0.014), diabetes (-0.022; 95% CI: -0.032, -0.014), and obesity (-0.021; 95% CI: -0.033, -0.011) with cognitive function, whereas the mediation effect was not observed for having hypercholesterolemia. The estimated proportions mediated were 37.4% for hypertension and 16.7% for diabetes. DNA methylation may be an important mediator linking cardiometabolic risk factors to worse cognition and might even provide a potential target for dementia prevention.

Polygenic risk, childhood abuse and gene x environment interactions with depression development from middle to late adulthood: A U.S. national life-course study

OBJECTIVE

Utilizing national longitudinal data, this study examines how polygenic depression risk and childhood abuse interactively influence the life-course development of depressive conditions from middle to late adulthood.

METHOD

Data from 7512 participants (4323 females and 3189 males) of European ancestry aged 51-90, retrieved from the U.S. Health and Retirement Study (1992-2020), were analyzed. Childhood physical abuse and polygenic depression score were the primary predictors. Depressive symptoms were assessed using the Center for Epidemiologic Studies-Depression (CESD) scale, and clinical depression risk was a binary indicator. Growth-curve linear mixed and logit mixed-effects models were conducted for analysis.

RESULTS

Increasing polygenic depression scores were associated with elevated CES-D levels and potential risks of clinical depression. Males experienced more detrimental effects of childhood abuse on depression development from ages 51 to 90 years. In contract, non-maltreated females generally exhibited higher depressive symptoms and clinical depression risk than males. A significant interactive effect was found between polygenic depression risk and childhood abuse among males. Higher depression levels and clinical risk were observed with increasing polygenic depression score among maltreated males, surpassing those of females with standardized polygenic score ≥0 from age 51 to 90 years.

CONCLUSIONS

The interaction between childhood abuse and genetic factors significantly shaped lifelong depression trajectories in males, while the negative impact of abusive parenting remained constant regardless of polygenic depression risk among females. Individualized prevention and intervention strategies could be crucial in mitigating lifelong depression development, especially for high-genetic-risk males with a history of childhood physical abuse.

Associations for Sense of Purpose with Smoking and Health Outcomes Among Adults with Diabetes

BACKGROUND

Health complications from diabetes place major strain on individuals, financially and emotionally. The onset and severity of these complications are largely driven by patients' behaviors, making psychosocial factors that influence behaviors key targets for interventions. One promising factor is sense of purpose or the degree to which a person believes their life has direction.

METHOD

The current study investigated whether sense of purpose predicts self-rated health, cardiovascular disease, and smoking status among adults with diabetes concurrently and prospectively. Moreover, it tested whether these associations held across multiple samples and cultures. Coordinated analysis using 12 datasets cross-sectionally and eight longitudinally (total N = 7277) estimated the degree to which sense of purpose is associated with subjective health, smoking status, and cardiovascular disease among adults with diabetes. Coordinated analysis allows for greater generalizability of results across cultures, time periods, and measurement instruments. Datasets were included if they concurrently included a measure of sense of purpose and diabetes status and at least one health measure: self-rated health, current smoking status, or heart condition status.

RESULTS

Sense of purpose was associated with higher self-rated health, smoking status, and cardiovascular disease cross-sectionally and self-rated health prospectively. Purpose was unassociated with changes in health over time.

CONCLUSION

These results highlight the relationship of a key individual difference, sense of purpose, to the behaviors and outcomes of adults with diabetes. While more research is needed to determine the boundaries of this relationship, it seems sense of purpose may be considered in the future as a potential target for intervention.

An exploration of neighborhood characteristics, psychosocial resilience resources, and cognitive functioning among midlife and older black adults

OBJECTIVES

While existing research has shown that Black adults have worse cognitive functioning than their White counterparts, the psychosocial correlates of cognitive functioning for Black older adults are understudied. The objective of this study was to investigate the relationships among perceived neighborhood characteristics, psychosocial resilience resources, and cognitive functioning among midlife and older Black adults.

METHODS

Data were from 3,191 Black adults ages 51+ in the 2008-2016 waves of the Health and Retirement Study to examine associations among neighborhood characteristics, psychosocial resilience (sense of purpose, mastery, and social support), and cognitive functioning among Black adults. Multilevel linear regression models assessed direct effects of neighborhood characteristics and psychosocial resources on cognitive functioning. We then tested whether psychosocial resources moderated the association between neighborhood characteristics and cognitive functioning.

RESULTS

Mean levels of cognitive functioning, sense of purpose, social support, and mastery were significantly related to neighborhood disorder and discohesion. Regression results showed that levels of neighborhood disorder and high discohesion were significantly associated with cognitive functioning. Sense of purpose was positively associated with cognitive functioning, net of neighborhood characteristics. However, only social support moderated the association between neighborhood discohesion and cognition.

CONCLUSIONS

These findings demonstrate the importance of examining psychosocial and contextual risk and resilience resources among midlife and older Black adults. This work may inform the development of cognitive behavioral interventions aimed at increasing sense of purpose to promote and enhance cognitive resiliency among Black adults. Altogether, this work may have implications for policy aimed at advancing cognitive health equity.

Functional limitation among middle age and older adults: Exploring cross-national gender disparities

OBJECTIVE

Functional limitations are prevalent among aging demographics, especially women. Structural and health factors, which vary worldwide, influence rates of functional limitations. Yet, gender disparities in functional limitation remain unclear in a global context.

METHODS

We use 2018 data from the Health and Retirement Study (HRS) international family of studies with respondents ages 50-64 and (n = 87,479) and 65-89 (n = 92,145) to investigate gender disparities in large muscle functional limitation (LMFL) across 10 countries/regions using mixed effects logistic regression, with special attention to structural indicators of inequality and health.

RESULTS

Among both women and men, LMFL was generally higher in China, India, Mexico, United States, and Baltic States than in England, Scandinavia, Southern Europe, Eastern Europe, and Western Europe. The gender disparity in LMFL gradually declined at older ages in India, China, Mexico, and United States, while this disparity gradually increased at older ages throughout Europe. Among middle age respondents, the greater risk of LMFL for women in countries/regions with a high GII was no longer observed after accounting for comorbidities. Among older respondents, a lower risk of LMFL for women in countries/regions with a high GII was not observed until accounting for comorbidities.

DISCUSSION

Our findings suggest that rates of LMFL are higher in middle-income countries than high-income countries, especially among women, and in countries with a higher GII. In addition, consideration of comorbidities was integral to these relationships. Thus, national/regional contexts inform differential rates of functional limitation, particularly as it relates to gender.

Association between longest-held occupation and mortality risk

BACKGROUND

Occupation is associated with a large part of daily activities, affecting lifestyle and social status. However, limited research exists on the association between longest-held occupation (LHO) and early mortality. We examine if LHO is associated with mortality risk among US adults 51 years of age and older.

METHODS

Using Health and Retirement Study data from 1992 to 2020, we followed 26,758 respondents 51 years of age and older for up to 29 years. We used competing-risks analysis methodology to estimate the risk of mortality.

RESULTS

Across the average 20.5 follow-up years, women with LHO in the categories of machine operators (subhazard ratio [SHR]: 1.42), food preparation (SHR: 1.39), handlers and helpers (SHR: 1.35), and sales (SHR: 1.15), were more likely to die earlier than women with the LHO in the professional and technical support occupation, the reference occupation. Men with LHO in the categories of food preparation (SHR: 1.43), machine operators (SHR: 1.36), personal services (SHR: 1.34), handlers and helpers (SHR: 1.32), protective services (SHR: 1.31), clerical (SHR: 1.27), farming and fishing (SHR: 1.26), sales (SHR: 1.23), and precision production (SHR: 1.20) had elevated risks of mortality compared to men whose LHO was in the referent professional and technical support occupation.

CONCLUSIONS

Findings from this study provide comprehensive and current evidence that occupation can be one of the risk factors for adverse health outcomes and ultimately for early mortality.

Physical activity initiated from midlife on risk of dementia and cognitive impairment: The Health and Retirement Study

BACKGROUND

Physical activity is associated with lower risk of dementia and cognitive impairment, but existing randomized controlled trials have shown conflicting results. As cognitive decline occurs decades before the onset of dementia, physical activity interventions initiated in late life may have missed the potential window for prevention. An ideal trial of physical activity initiated from midlife and lasts till incident dementia and cognitive impairment in late life is not feasible. We aimed to estimate the effectiveness of a hypothetical physical activity intervention initiated from midlife on reducing dementia and cognitive impairment by emulating target trials using observational data.

METHODS

The Health and Retirement Study was used to emulate target trials among noninstitutionalized participants aged 45 to 65 years with normal cognition who were physically inactive in the previous 2 years. Cognitive status was determined based on Langa-Weir classification of cognitive function (including immediate and delayed word recall tests, serial sevens subtraction, counting backward). Individuals were categorized as initiating physical activity or not, based on the self-reported physical activity. Intention-to-treat and per-protocol analysis were conducted with pooled logistic regression models with inverse-probability of treatment and censoring weights to estimate risk ratios (RRs), and 95% confidence intervals (95% CIs) were calculated with 200 sets of bootstrapping.

RESULTS

Among 1505 participants (average age 57.6 ± 4.8 years, 67% women, 76.5% White), 72 cases of dementia and 409 cases of cognitive impairment occurred. After 12 years of follow-up, physical activity reduced dementia (RR = 0.70, 95% CI: 0.43, 0.99) for intention-to-treat analysis, and reduced dementia (RR = 0.51, 95% CI: 0.19, 0.99) and cognitive impairment (RR = 0.77, 95% CI: 0.61, 0.92) for per-protocol analysis. No significant reduction was found among older adults.

CONCLUSIONS

Physical activity initiated during midlife may reduce dementia and cognitive impairment in late life, which highlights the importance of preventing cognitive outcomes at an earlier stage of life.

Association between prescription opioid use and heart failure: Cohort studies and Mendelian randomization analysis

BACKGROUND

Prescription opioid use (POU) has been shown to lead to cardiovascular disease (CVD), but its association with heart failure has not been well studied. We investigated the potential causal association between POU and HF using cohort studies and Mendelian Randomization (MR) analysis.

METHODS

Initially, we examined the longitudinal association between POU and HF using the data from the Health and Retirement Study (HRS) and the UK biobank. Next, we employed a two-sample MR analysis using summary statistics from genome-wide association studies (GWAS) to assess the potential causal associations between POU and HF.

RESULTS

During a median of 3.8 and 13.8 years of follow-up, there were 441(8.04 per 1000 person-year) and 16,170 (3.96 per 1000 person-year) HF cases in the HRS and the UK biobank, respectively. After adjusting for covariates, participants who used prescription opioids had a 32% increased risk of developing HF, compared with non-users (HR = 1.32, 95%CI: 1.26-1.38, P < 0.001). In the MR analysis, summary statistics for POU were obtained from 78,808 UK Biobank study participants, and summary data for HF were obtained from 218,792 participants of a European population. A causal effect of genetic liability for POU on an increased risk of HF (OR = 1.16, 95% CI = 1.06, 1.27, P = 0.001) was suggested. The results were generally consistent in the sensitivity analysis, and no pleiotropy or heterogeneity were observed.

CONCLUSIONS

POU is associated with a high risk of HF. Our findings provide new insight into prescription opioid use among populations at risk of heart failure. More studies are needed to validate our results and further investigate the underlying mechanisms.

Relationship between cognitive function and sleep quality in middle-aged and older adults for minimizing disparities and achieving equity in health: Evidence from multiple nationwide cohorts

BACKGROUND

Cognitive decline, a heavy burden on middle-aged and older adults as global aging is aggravated, was found to be associated with sleep quality. However, the country-between heterogeneity of the association prevented us from quantifying underlying relationship and identifying potential effect modifiers for vulnerable populations and targeted interventions.

METHODS

We collected data from 79,922 eligible adults in five nationwide cohorts, examined the respective relationships between cognitive function and sleep quality, synthesized underlying average relationships by meta-analysis, and explored effect modifiers by meta-regressions. Additionally, we conducted subgroup and interaction analyses to identify vulnerable populations and to determine their disparities in vulnerability.

RESULTS

Although country-between disparities exist, cognitive function is robustly associated with sleep quality in middle-aged and older adults worldwide, with an effect (β) of 0.015 [0.003, 0.027]. Executive function is the subdomain most relevant to sleep quality. Disparities in the effects of sleep quality on subdomains exist in populations with different sexes (orientation: βfemale/βmale = 1.615, P = 0.020), marital statuses (orientation: βunmarried/βmarried = 2.074, P < 0.001), education levels (orientation:βuneducated/βeducated = 2.074, P < 0.001) and chronic disease statuses (memory: βunhealthy/βhealthy = 1.560, P = 0.005).

CONCLUSIONS

Cognitive function decreases with worsening sleep quality in middle-aged and older adults. Vulnerability to poor sleep generally persists in singles, females, the uneducated and people with chronic diseases. To minimize disparities and achieve health equity, we advocate for targeted interventions, i.e., encouraging socialization in singles, confirming effectiveness of hormone replacement therapy in females, employing compulsory education in middle-aged and older adults.

Wealth-related inequalities in self-reported health status in the United States and 14 high-income countries

OBJECTIVE

To examine wealth-related inequalities in self-reported health status among older population in the United States and 14 European countries.

DATA SOURCES AND STUDY SETTING

We used secondary individual-level data from Health and Retirement Survey (HRS) and the Survey of Health, Ageing, and Retirement in Europe (SHARE) in 2011 and 2019.

STUDY DESIGN

In this cross-sectional study, we used two waves from HRS (wave 10 and 14) and SHARE (wave 4 and 8) to compare wealth-related health inequality across countries, age groups, and birth cohorts. We estimated Wagstaff concentration indices to measure these inequalities across three age groups (50-59, 60-69, 70-79) and two birth cohorts (1942-1947, 1948-1953) in the US and 14 European countries.

DATA COLLECTION/EXTRACTION METHODS

We performed secondary analysis of survey data.

PRINCIPAL FINDINGS

Focusing on older population, we found evidence of wealth-related inequalities in self-reported health status across several high-income countries, with the US demonstrating higher levels of inequality than its European counterparts. The magnitude of these inequalities with respect to wealth remained unchanged over the study period across all countries. Our findings also suggest that wealth-related health inequalities differ at different stages of workforce engagement, especially in the United States. This could be explained either by potential redistributive effects of retirement or by uneven survivor effect, as less wealthy may drop out of the observations at a greater rate partly due to their poorer health.

CONCLUSIONS

Wealth-related inequalities in self-reported health status are strong and persistent across countries. Our results suggest that there is meaningful variation across high-income countries in health-wealth dynamics that merits further investigation to better understand whether certain health or welfare systems are more equitable. They also highlight the need to consider social policy and wealth redistribution mechanisms as strategies for improving population health among the less wealthy, in the United States and elsewhere.

Association of Gum Treatment with Cognitive Decline and Dementia Risk among Older Adults with Periodontal Symptoms: A 12-Year Prospective Cohort Study

INTRODUCTION

This study examines the associations of gum treatment with cognitive decline and dementia risk among older adults with periodontal symptoms in the USA.

METHODS

A cohort of 866 adults aged ≥50 with periodontal symptoms was recruited for the 2008 Health and Retirement Study "Dental Health Experimental Module" and followed until 2020. Cognitive function was assessed with the Telephone Interview for Cognitive Status (TICS). Dementia status was ascertained with the Langa-Weir algorithm based on TICS scores and proxy assessments. Linear mixed-effects model and multivariable Cox regression models were utilized to analyze the associations of gum treatment with cognitive decline and the risk of dementia, respectively.

RESULTS

Of 866 participants (mean age 67.7, 61.4% women), 105 (12.1%) developed dementia with a median follow-up of 9 (IQR, 6-10) years. The dementia incidence rates were lower in the group with gum treatment (7.4 vs. 12.9 per 1,000 person-years). Compared with participants who did not have gum treatment, those with gum treatment experienced a decline in TICS score that was on average 0.025 (95% CI, 0.005-0.044) points less per year and a 38% lower incidence of dementia (hazard ratio, 0.62; 95% CI, 0.41-0.93). These associations were consistent across participants with a different severity of periodontal symptoms and sociodemographic characteristics (age, sex, race, ethnicity, and education) except for income levels.

CONCLUSION

Prompt gum treatment for older adults with periodontal symptoms may be beneficial for their cognitive health.

Weakness Status is Differentially Associated with Time to Diabetes in Americans

Background

The purpose of this study was to evaluate the associations of (1) individual absolute and body size normalized weakness cut-points, and (2) the collective weakness classifications on time to diabetes in Americans.

Methods

We analyzed data from 9577 adults aged at least 50-years from the Health and Retirement Study. Diabetes diagnosis was self-reported. A handgrip dynamometer measured handgrip strength (HGS). Males with HGS <35.5 kg (absolute), <0.45 kg/kg (normalized to body weight), or <1.05 kg/kg/m2 (normalized to BMI) were categorized as weak. Females were classified as weak if their HGS was <20.0 kg, <0.337 kg/kg, or <0.79 kg/kg/m2. Compounding weakness included falling below 1, 2, or all 3 cut-points.

Results

Persons below the body weight normalized weakness cut-points had a 1.29 (95% confidence interval (CI): 1.15-1.47) higher hazard for incident diabetes, while those below the BMI normalized cut-points had a 1.30 (CI: 1.13-1.51) higher hazard. The association between absolute weakness and incident diabetes was insignificant (hazard ratio: 1.06; CI: 0.91-1.24). Americans below 1, 2, or all 3 collective weakness categories had a 1.28 (CI: 1.10-1.50), 1.29 (CI: 1.08-1.52), and 1.33 (CI: 1.09-1.63) higher hazard for the incidence of diabetes, respectively.

Conclusions

Our findings indicate that while absolute weakness, which is confounded by body size, was not associated with time to diabetes, adjusting for the influence of body size by normalizing HGS to body weight and BMI was significantly associated with time to diabetes. This suggests that muscle strength, not body size, may be driving such associations with time to diabetes.

Decomposing the association of psychosocial wellbeing with all-cause mortality: the mediating role of physical health and lifestyle factors

PURPOSE

This study quantified the effect of 48 psychosocial constructs on all-cause mortality using data from 7,698 individuals in the U.S. Health and Retirement Study.

METHODS

Latent class analysis was used to divide participants into mutually exclusive psychosocial wellbeing groups (good, average, or poor) which was subsequently considered as the exposure. Mediation analysis was then conducted to determine the direct effect of the psychosocial wellbeing groups and the indirect (mediating) effects of physical health (functional status and comorbid conditions) and lifestyle factors (physical activity, smoking, and alcohol consumption) on overall survival. We also created a composite health index measure representing the summative effect of the mediators.

RESULTS

We observed a strong and statistically significant total effect (TE) between survival time and psychosocial wellbeing group (survival time ratio (SR) = 1.73, 95% confidence interval (CI):1.50,2.01 when comparing good to poor). Mediation analysis revealed that the direct effect via psychosocial wellbeing group accounted for more than half of the TE (SR = 1.46, 95% CI:1.27,1.67). The composite health index measure mediated 36.2% of the TE with the natural indirect effect SR of 1.18 (95% CI:1.13,1.22).

CONCLUSION

Our findings demonstrate the interconnectedness between psychosocial wellbeing and physical health and lifestyle factors on survival.

Modifiable and Non-Modifiable Risk Factors for Dementia Among Non-Hispanic White and Black Populations Aged 50-64 in the United States, 2006-2016

BACKGROUND AND OBJECTIVES

Non-Hispanic Black populations (NHB) have a significantly higher prevalence of dementia than non-Hispanic Whites in the U.S., and the underlying risk factors may play a role in this racial disparity. We aimed to calculate risk scores for dementia among non-Hispanic White (NHW) and non-Hispanic Black populations aged 50-64 years over a period of 10 years, and to estimate potential differences of scores between NHW and NHB.

RESEARCH DESIGN AND METHODS

The Health and Retirement Study from 2006 to 2016 was used to calculate the Cardiovascular Risk Factors, Aging, and Incidence of Dementia (CAIDE) risk score, a validated score for predicting dementia risk. Weighted average CAIDE score, as well as CAIDE score for modifiable factors hypertension, obese, hypercholesterolemia, physical inactivity), and non-modifiable factors (age, sex, education) were calculated for adults aged 50-64 years with normal cognition for 2006-2008, 2010-2012, 2014-2016. The associations of race with CAIDE score and elevated CAIDE score were examined.

RESULTS

A total of 10,871 participants were included in the analysis. The CAIDE score showed declining trends for NHB from 2006 to 2016, while NHB consistently had a higher total CAIDE score and CAIDE score for modifiable factors from 2006 to 2016, but not for non-modifiable factors.

DISCUSSION AND IMPLICATIONS

NHB had a higher level of dementia risk factors than NHW among adults aged 50-64 years in the U.S. from 2006 to 2016, and the difference is attributable to modifiable risk factors, which holds promise for risk reduction of dementia.