Economic hardship over twenty-two consecutive years of adult life and markers of early ageing: physical capability, cognitive function and inflammation

Life course socioeconomic position and cognitive aging in later life: A scoping review

BACKGROUND AND OBJECTIVES

Low socioeconomic position (SEP) throughout the life course is related to poorer cognitive health in later life, but debate ensues on the life course models for this association. To advance inquiry on the topic, we conducted a scoping review.

RESEARCH DESIGN AND METHODS

We examined the association between life course SEP and cognitive function in later life in observational studies-considering cognition both as a cross-sectional level and as a longitudinal trajectory across cognitive domains-and assessed whether the empirical evidence supported life course models. We focused on studies in the general population with cognition measured in the second half of life (45 +). Forty-two studies (21 datasets) were included representing 595,276 participants (201,375 across unique datasets) from 46 countries.

RESULTS

For cognitive level, studies consistently found associations between SEP at various stages of the life course, both in overall cognition and across specific cognitive domains. These associations were generally robust to confounding and mediating factors. For cognitive trajectory, studies showed inconclusive associations with SEP across life course and across cognitive domains. Results supported the sensitive period, pathway, and accumulation models, but not the critical period model. Results supported that education acts as a pathway (and potential mediator) in the association between early-life SEP and later-life cognition.

DISCUSSION AND IMPLICATIONS

SEP throughout the life course has a robust association with later-life cognitive level, but not decline. Early-life cognitive enrichment for young people raised in socioeconomically disadvantaged households may reduce the SEP gap in cognitive functioning during later life.

The long-term effects of housing insecurity in young adulthood on subsequent material hardship, physiological and mental health

Economic and material hardship, including housing insecurity - limited or uncertain availability or access to safe, quality, and affordable housing - is strongly linked to negative physical and mental health outcomes among adolescents and adults. However, data limitations and the inherent selectivity of housing insecurity have hindered comprehensive analysis of its long-term effects on physiological and mental health. This study uses data from The National Longitudinal Study of Adolescent to Adult Health (Add Health) to construct a sample of participants who experienced housing insecurity between the ages of 18-26 (Wave III) to a suitable control group using propensity score matching. We assess the effects of housing insecurity on (1) material hardship at Wave IV (ages 24-32), (2) allostatic load (AL) and depression symptoms at Waves IV and V (ages 33-43), and (3) the change in allostatic load and depression symptoms from Wave IV to V. Further, we evaluate whether effects differ by sex. Experiencing housing insecurity is associated with a significantly higher likelihood of experiencing material hardship at Wave IV and significantly worse depressive symptoms at both Waves IV and V. The treatment effects are more pronounced among women, with housing insecurity being linked to a significant increase in allostatic load from Wave IV to Wave V exclusively for women. Our results provide crucial support that housing insecurity is not just an outcome of economic hardship but a cause of it in the future, with downstream effects on health and well-being, particularly for women.

Housing insecurity pathways to physiological and epigenetic manifestations of health among aging adults: a conceptual model

Introduction

Housing insecurity is a social determinant of health, as evidenced by its associations with mental, physical, and biological outcomes. The scientific understanding of the mechanisms by which housing insecurity is associated with health is still limited. This review adapts existing stress process models to propose a conceptual model illustrating potential pathways linking the specific stressor of housing insecurity to physiological and epigenetic manifestations of stress among aging adults.

Methods

This narrative review examines literature across multiple fields, including public health, psychology, and sociology. The literature selected for this review was identified through scientific databases including Web of Science, PubMed, JSTOR, and Google Scholar; primarily peer-reviewed empirical studies, literature reviews, and research reports published in English between 1981 and 2024; and principally based in the United States context. A synthesis of this literature is presented in a proposed conceptual model.

Results

The literature supports the existence of two main predictors of housing insecurity: sociodemographic characteristics and the historical/current context. The main mediating pathways between housing insecurity and manifestations of stress include health behaviors, psychosocial resources, and structural resources. Moderating factors affecting the associations between housing insecurity and manifestations of stress include government assistance, chronic discrimination/unfair treatment, and individual differences. These interdependent mediating and moderating mechanisms affect stressor reactivity, a proximal manifestation of stress, which contributes to the physiological and epigenetic distal manifestations of stress in aging adults.

Discussion and implications

The prevalence of housing insecurity among aging adults is growing in the United States, with significant implications for public health and health disparities, given the growing percentage of aging adults in the population. Further empirical testing of the mediating and moderating mechanisms proposed in the conceptual model will elucidate how housing insecurity is connected to health and provide insight into preventive strategies to ameliorate the adverse effects of housing insecurity on biological health among aging adults.

Associations between Recession Hardships and Subjective and Objective Sleep Measures in the Midlife in the United States Study: Race and Gender Differences

Objectives

This study investigates the associations of retrospective reports of Recession hardships with 10-year changes in subjective and objective indicators of sleep, and whether these associations differ by race and gender.

Methods

501 adults (14.57% Black; 54.49% female) from the Midlife in the United States (MIDUS) study reported on the subjective Pittsburgh Sleep Quality Index (PSQI) across two waves (pre-Recession, collected 2004-2009; post-Recession, collected 2017-2022), as well as Recession hardships since 2008. A sub-sample of 201 adults (25.37% Black; 58.21% female) provided objective actigraphy-measured sleep data (total sleep time, sleep onset latency, sleep efficiency) across the two waves.

Results

Descriptive analyses revealed Black participants had higher average Recession hardships, poorer post-Recession PSQI scores, and poorer post-Recession actigraphy sleep quantity and quality compared to white participants. Females had higher average Recession hardships compared to males; and reported poorer post-Recession PSQI, but had better objective post-Recession sleep quantity and quality compared to males. Regression models showed Recession hardships (across overall events, and sub-domains of financial and housing hardships) were associated with poorer PSQI and actigraphy-measured sleep efficiency following the Recession, adjusting for sociodemographic covariates, corresponding pre-Recession sleep variables, and pre-Recession chronic conditions. There was no evidence for significant moderation by race on sleep outcomes. However, gender moderation indicated associations between housing hardships and poorer actigraphy-measured sleep efficiency were more apparent for females than for males.

Conclusions

Findings indicate that Recession hardships (particularly in financial and housing domains) may be manifested in poor sleep. Racial and gender groups may have differential exposure and sleep-related reactivity to Recession hardships.

Childhood Adversities and Caregiving for Older Parents: Building Capacity for a Caring Society

OBJECTIVES

This study investigates the relationships between childhood adversities and the provision of informal care for older parents in later life in China.

METHODS

The data came from 4 waves of the China Health and Retirement Longitudinal Study (N = 20,047). Using multilevel logistic regression models, we examined the relationships between adverse experiences in childhood and both the propensity and intensity of caregiving for older parents. Drawing on the regression results, we then estimated the total number of caregivers for older parents in China.

RESULTS

Experiencing 1 additional childhood adversity was associated with a decrease of 8% in the odds of providing informal care (p < .001). The association between childhood adversity and caregiving remained significant after sociodemographic factors and later-life outcomes were controlled for. We estimated that 58.3 million middle-aged adults in China were providing care for parents in 2020. Had people experienced 1 fewer adversity in their childhood, there would have been 2.2 million more caregivers in 2020. Had they experienced 2 fewer adversities, there would have been 3.4 million more caregivers.

DISCUSSION

The factors associated with informal caregiving can be traced back to early-life experiences. To address the shortage of informal care supply, it is crucial to foster a caring culture from the very beginning of human development.

Report on the Joint Workshop on the Relations between Health Inequalities, Ageing and Multimorbidity, Iceland, May 3-4, 2023

This paper is a summary of key presentations from a workshop in Iceland on May 3-4, 2023 arranged by Aarhus University and with participation of the below-mentioned scientists. Below you will find the key messages from the presentations made by: Professor Jan Vandenbroucke, Department of Clinical Epidemiology, Aarhus University, Emeritus Professor, Leiden University; Honorary Professor, London School of Hygiene & Tropical Medicine, UKProfessor, Chair Henrik Toft Sørensen, Department of Clinical Epidemiology, Aarhus University and Aarhus University Hospital, DenmarkProfessor David H. Rehkopf, Director, the Stanford Center for Population Health Sciences, Stanford University, CA., USProfessor Jaimie Gradus, Department of Epidemiology, School of Public Health, Boston University, Boston, Massachusetts, USProfessor Johan Mackenbach, Emeritus Professor, Department of Public Health, Erasmus University Rotterdam, HollandProfessor, Chair M Maria Glymour, Department of Epidemiology, Boston University School of Public Health, Boston University, Boston, Massachusetts, USProfessor, Dean Sandro Galea, School of Public Health, Boston University, Boston, Massachusetts, USProfessor Victor W. Henderson, Departments of Epidemiology & Population Health and of Neurology & Neurological Sciences, Stanford University, Stanford, CA, US; Department of Clinical Epidemiology, Aarhus University, Aarhus, DK.

Are trajectories of personality and socioeconomic factors prospectively associated with midlife cognitive function? Findings from a 12-year longitudinal study of Mexican-origin adults

Problems with memory, executive function, and language are a significant public health concern, especially when they begin during midlife. However, there is relatively little work on risk and protective factors for cognitive function in middle adulthood. Using data from 883 Mexican-origin adults assessed up to 6 times across 12 years (Mage at Time 1 = 38.2 years; range = 27-63 years), the present study examined whether developmental trajectories (levels and slopes) of Big Five personality domains and socioeconomic factors (per capita income, economic stress) were prospectively associated with cognitive function (memory, mental status, verbal fluency) at the final assessment. We found that individuals with higher levels of, and smaller decreases in, Neuroticism had worse cognitive function 12 years later. Further, individuals with higher initial Conscientiousness had better subsequent memory, mental status, and verbal fluency, and individuals with higher Openness and Extraversion had better subsequent verbal fluency (but not memory or mental status). The trajectories of per capita income and economic stress were robustly associated with cognitive function, such that higher initial levels and greater increases in socioeconomic resources had protective associations, whereas higher levels and greater increases in economic stress had deleterious associations with cognitive function. Higher education level was associated with better cognitive function 12 years later. These findings suggest that changes in personality and socioeconomic factors across adulthood are associated with cognitive function, which may be informative for interventions to support healthier cognitive aging starting at least as early as midlife. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Housing Insecurity Among Patients With Cancer

Social determinants of health are the economic and environmental conditions under which people are born, live, work, and age that affect health. These structural factors underlie many of the long-standing inequities in cancer care and outcomes that vary by geography, socioeconomic status, and race and ethnicity in the United States. Housing insecurity, including lack of safe, affordable, and stable housing, is a key social determinant of health that can influence-and be influenced by-cancer care across the continuum, from prevention to screening, diagnosis, treatment, and survivorship. During 2021, the National Cancer Policy Forum of the National Academies of Science, Engineering, and Medicine sponsored a series of webinars addressing social determinants of health, including food, housing, and transportation insecurity, and their associations with cancer care and patient outcomes. This dissemination commentary summarizes the formal presentations and panel discussions from the webinar devoted to housing insecurity. It provides an overview of housing insecurity and health care across the cancer control continuum, describes health system interventions to minimize the impact of housing insecurity on patients with cancer, and identifies challenges and opportunities for addressing housing insecurity and improving health equity. Systematically identifying and addressing housing insecurity to ensure equitable access to cancer care and reduce health disparities will require ongoing investment at the practice, systems, and broader policy levels.

Student Debt and Cardiovascular Disease Risk Among U.S. Adults in Early Mid-Life

INTRODUCTION

Student loan debt has become common for young adults in the U.S. and is correlated with poor physical and mental health. It is unclear how the accumulation or repayment of student debt is associated with longer-term cardiovascular risks and chronic inflammation.

METHODS

Nationally representative data collected between 1994 and 2018 from >4,000 participants of a U.S. cohort study were analyzed in 2021 to assess the associations among change in student debt between young adulthood and early mid-life, 30-year Framingham cardiovascular disease risk scores, and C-reactive protein levels.

RESULTS

Ordinary least squares regression revealed higher cardiovascular disease and C-reactive protein risks among those in households who became indebted or were consistently in debt between young adulthood and early mid-life than among those in households who were either never in debt or repaid their loans. This pattern persisted after adjustments for degree completion, socioeconomic measures, and other sources of debt.

CONCLUSIONS

These findings provide a benchmark for widening health inequalities among a cohort bearing more student debt than any other in U.S.

HISTORY

As student debt accumulates, within-cohort disparities in cardiovascular disease and related morbidities may undermine the health benefits of postsecondary education.

Association of Medical Financial Hardship and Mortality Among Cancer Survivors in the United States

BACKGROUND

Cancer survivors frequently experience medical financial hardship in the United States. Little is known, however, about long-term health consequences. This study examines the associations of financial hardship and mortality in a large nationally representative sample of cancer survivors.

METHODS

We identified cancer survivors aged 18-64 years (n = 14 917) and 65-79 years (n = 10 391) from the 1997-2014 National Health Interview Survey and its linked mortality files with vital status through December 31, 2015. Medical financial hardship was measured as problems affording care or delaying or forgoing any care because of cost in the past 12 months. Risk of mortality was estimated with separate weighted Cox proportional hazards models by age group with age as the timescale, controlling for the effects of sociodemographic characteristics. Health insurance coverage was added sequentially to multivariable models.

RESULTS

Among cancer survivors aged 18-64 years and 65-79 years, 29.6% and 11.0%, respectively, reported financial hardship in the past 12 months. Survivors with hardship had higher adjusted mortality risk than their counterparts in both age groups: 18-64 years (hazard ratio [HR] = 1.17, 95% confidence interval [CI] = 1.04 to 1.30) and 65-79 years (HR = 1.14, 95% CI = 1.02 to 1.28). Further adjustment for health insurance reduced the magnitude of association of hardship and mortality among survivors aged 18-64 years (HR = 1.09, 95% CI = 0.97 to 1.24). Adjustment for supplemental Medicare coverage had little effect among survivors aged 65-79 years (HR = 1.15, 95% CI = 1.02 to 1.29).

CONCLUSION

Medical financial hardship was associated with mortality risk among cancer survivors in the United States.

Inflammatory markers and lung function in relation to indoor and ambient air pollution

Ambient air pollution causes a range of adverse health effects, whereas effects of indoor sources of air pollution are not well described in high-income countries. We compared hazards of ambient air pollution and indoor sources with respect to important biomarkers of cardiorespiratory effects in terms of lung function and systemic inflammation in a middle-aged Danish cohort. Our cohort comprised 5199 men and women aged 49-63 years at the recruitment during April 2009 to March 2011, with information on exposure to second-hand smoke (SHS) and use of candles, wood stove, kerosene heater and gas cooker as well as relevant covariates. Ambient air pollution exposure was assessed as 2-year mean nitrogen dioxide (NO₂) at the address (mean ± SD: 17.1 ± 9.9 μg/m³) and 4-day average levels of particulate matter with diameter <2.5 μm (PM_2.5; mean ± SD: 12.5 ± 6.0 μg/m³) in urban background. Lung function was assessed as % predicted forced expiratory volume in the first second (FEV1) and inflammatory markers comprised interleukin-6 (IL-6), IL-10, IL-18, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), and high sensitivity C-reactive protein (hs-CRP). We used random-effect regression models controlling for potential confounders as well as models with further adjustment for self-reported health or for all other exposures. In models adjusted for confounders FEV1 was inversely associated with exposure to NO₂, (-0,83% per 10 μg/m³; 95% CI: -1.26; -0.41%), SHS (-0.56% per 1 of 5 categories increment; 95% CI: -0.89; -0.23%), and gas cooker without hood (-0.89%; 95% CI: -1.62; -0.17%), whereas use of wood stove and candles showed positive associations, although these attenuated by mutual adjustment for all exposures or self-reported health. IL-6 showed positive associations with NO₂ (6.30% increase in log-transformed values per 10 μg/m³; 95% CI: 3.54; 9.05%), PM_2.5 (7.82% per 10 μg/m³; 95% CI: 3.35; 12.4%), SHS (4.38% per increase of 1 of 5 categories; 95% CI: 2.22; 6.54%) and use of kerosene (13.8%; 95% CI: 2.51; 25.1%), whereas the associations with use of wood stove and candles were inverse. PM_2.5 and NO₂ showed positive associations with IFN-γ and TNF-α, while PM_2.5 further associated with IL-10 and IL-18. Hs-CRP was inversely associated with use of candles. These results suggest that the levels of exposure to ambient air pollution and SHS are more harmful than are the levels of exposure to indoor combustion sources from candles and wood stoves in a high-income setting.

Do partnership dissolutions and living alone affect systemic chronic inflammation? A cohort study of Danish adults

BACKGROUND

Partnership breakups and living alone are associated with several adverse health outcomes. The aim of this study, carried out in Denmark, is to investigate whether accumulated numbers of divorces/partnership breakups or years lived alone across 26 years of adult life are associated with levels of inflammation, and if vulnerability with regards to gender or educational level can be identified.

METHODS

4835 participants from the Copenhagen Aging and Midlife Biobank (CAMB) aged 48-62 years were included. Data on accumulated numbers of partnership breakups and years living alone were retrieved from a national standardised annual register. Inflammatory markers interleukin 6 (IL-6) and high sensitivity C-reactive protein (hsCRP) were measured in blood samples. Multivariate linear regression analyses were adjusted for age, educational level, early major life events, body mass index, chronic diseases, medicinal intake affecting inflammation, acute inflammation and personality scores.

RESULTS

For men, an association was found between an increasing number of partnership breakups or number of years living alone and higher levels of inflammatory markers. No such association was found for women, and no evidence of partnership breakups and educational level having a joint effect was found for either gender.

CONCLUSION

The findings suggest a strong association between years lived alone or accumulated number of partnership breakups and low-grade inflammation for middle-aged men, but not for women. Among those of either sex with a lower level of education, no specific vulnerability to accumulated years lived alone or number of breakups was identified.

Childhood adversity and healthy ageing: a study of the Chinese older population

This study examines the relationship between childhood adversities and healthy ageing in the Chinese older population. The data come from the China Health and Retirement Longitudinal Survey (CHARLS), a national survey that collected life history and ageing-related information on 9248 older people aged over 60 in 2014 and 2015. The analysis of healthy ageing focuses on seven indicators: IADL limitations, ADL limitations, cognitive functioning, depressive symptoms, life satisfaction, self-reported health, and chronic illness. Using k-means clustering, an unsupervised learning technique, we identified four qualitatively different groups according to their achievement in healthy ageing. We studied 17 types of childhood adversities and found that experiencing multiple childhood adversities is associated with a lower probability of achieving healthy ageing. This relationship is moderated by age and gender. Women are more vulnerable than men to the negative impacts of childhood adversities. The threat of childhood adversities to healthy ageing is greatly attenuated among people aged over 80. We argue that the policy response to healthy ageing should not be confined to those services and programmes that directly target older people. Instead, healthy ageing can be better addressed by concerted efforts in different areas of social policy.

The relationship between financial hardship and incident diabetic kidney disease in older US adults - a longitudinal study

Background

Financial hardship is associated with poor health, however the association of financial hardship and incident diabetic kidney disease (DKD) is unknown. This study aimed to examine the longitudinal relationship between financial hardship and incident DKD among older adults with diabetes.

Methods

Analyses were conducted in 2735 adults age 50 or older with diabetes and no DKD using four waves of data (2006–2012) from the Health and Retirement Study, a national longitudinal cohort. The primary outcome was incident DKD. Financial hardship was based on three measures: 1) difficulty paying bills; 2) food insecurity; and 3) cost-related medication non-adherence using validated surveys. A dichotomous financial hardship variable (0 vs 1 or more) was constructed based on all three measures. Cox regression models were used to estimate the association between financial hardship, change in financial hardship experience and incident DKD adjusting for demographics, socioeconomic status, and comorbidities.

Results

During the median follow-up period of 4.1 years, incident DKD rate was higher in individuals with versus without financial hardship (41.2 versus 27/1000 person years). After adjustment, individuals with financial hardship (HR 1.32, 95% CI 1.04–1.68) had significantly increased likelihood of developing DKD compared to individuals without financial hardship. Persistent financial hardship (adjusted HR 1.52 95% CI 1.06–2.18) and negative financial hardship (adjusted HR 1.54 95% CI 1.02–2.33) were associated with incident DKD compared with no financial hardship experience. However, positive financial hardship was not statistically significant in unadjusted and adjusted (adjusted HR 0.89 95% CI 0.55–1.46) models. Cost-related medication non-adherence (adjusted HR 1.43 95% CI 1.07–1.93) was associated with incident DKD independent of other financial hardship measures.

Conclusions

Financial hardship experience is associated with a higher likelihood of incident DKD in older adults with diabetes. Future studies investigating factors that explain the relationship between financial hardship and incident DKD are needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02373-3.

A systematic review of quantitative bias analysis applied to epidemiological research

BACKGROUND

Quantitative bias analysis (QBA) measures study errors in terms of direction, magnitude and uncertainty. This systematic review aimed to describe how QBA has been applied in epidemiological research in 2006-19.

METHODS

We searched PubMed for English peer-reviewed studies applying QBA to real-data applications. We also included studies citing selected sources or which were identified in a previous QBA review in pharmacoepidemiology. For each study, we extracted the rationale, methodology, bias-adjusted results and interpretation and assessed factors associated with reproducibility.

RESULTS

Of the 238 studies, the majority were embedded within papers whose main inferences were drawn from conventional approaches as secondary (sensitivity) analyses to quantity-specific biases (52%) or to assess the extent of bias required to shift the point estimate to the null (25%); 10% were standalone papers. The most common approach was probabilistic (57%). Misclassification was modelled in 57%, uncontrolled confounder(s) in 40% and selection bias in 17%. Most did not consider multiple biases or correlations between errors. When specified, bias parameters came from the literature (48%) more often than internal validation studies (29%). The majority (60%) of analyses resulted in >10% change from the conventional point estimate; however, most investigators (63%) did not alter their original interpretation. Degree of reproducibility related to inclusion of code, formulas, sensitivity analyses and supplementary materials, as well as the QBA rationale.

CONCLUSIONS

QBA applications were rare though increased over time. Future investigators should reference good practices and include details to promote transparency and to serve as a reference for other researchers.

The Association Between Income and Incident Homebound Status Among Older Medicare Beneficiaries

IMPORTANCE

A large and growing population of older adults with multimorbidity, cognitive impairment, and functional disability live in the community, but many never or rarely leave their homes. Being homebound is associated with decreased access to medical services, poor health outcomes, and increased mortality. Yet, it is unknown what factors, in particular socioeconomic factors, are associated with new onset of homebound status.

OBJECTIVE

To evaluate the association between income and risk of becoming homebound.

DESIGN

Observational cohort study using 2011 to 2018 data from the National Health and Aging Trends Study, a nationally representative sample of Medicare beneficiaries aged 65 years and older.

SETTING

Population-based study in the United States.

PARTICIPANTS

A total of 7,042 initially nonhomebound community-dwelling older adults.

EXPOSURE

Total annual household income at baseline (in 2011) measured via self-report.

OUTCOME

Annual measure of homebound status, defined as leaving home an average of 1 d/wk or less.

RESULTS

Over 7 years, 15.81% of older adults in the lowest income quartile (≤$15,003) became homebound, compared with only 4.64% of those in the highest income quartile (>$60,000). In a competing risks analysis accounting for risks of death and nursing home admission, and adjusted for clinical and demographic characteristics, those in the lowest income quartile had a substantially higher subhazard of becoming homebound than those in the highest income quartile (1.65; 95% confidence interval = 1.20-2.29). Moreover, we see evidence of a gradient in risk of homebound status by income quartile.

CONCLUSION AND RELEVANCE

Our work demonstrates that financial resources shape the risk of becoming homebound, which is associated with negative health consequences. In the context of existing income disparities, more support is needed to assist older adults with limited financial resources who wish to remain in the community.

The long-term effect of intra-European migration on cognitive abilities in later life

The study raises the question about the long-term effect of intra-European migration on cognitive abilities in later life. In contrast to previous research that compares migrants to natives of the destination country, this study uses stayers in the European origin countries as reference group for migrants who moved to another European country earlier in life and are now growing old abroad. Selection into migration is addressed methodologically by applying an instrumental variable approach. Using the Global Bilateral Migration Database to generate the country- and time-specific share of emigrants as instrument for migration, the results indicate that intra-European migration turns out to have a negative long-term effect on the level of cognitive abilities.