Childhood Socioeconomic Status and Later Life Cognition: Evidence From the Wisconsin Longitudinal Study

Disparate benefits of higher childhood socioeconomic status on cognition in young adulthood by intersectional social positions

OBJECTIVES

Emerging evidence supports the protective effects of higher childhood socioeconomic status (cSES) on cognition over the life course. However, less understood is if higher cSES confers benefits equally across intersecting social positions. Guided by a situational intersectionality perspective and the theory of Minority Diminished Returns (MDR), this study examined the extent to which associations between cSES and cognition in young adulthood are jointly moderated by racialized identity and region of childhood residence.

METHODS

Using data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), we used multilevel modeling to test associations between cSES and delayed recall and working memory 14 years later when participants were ages 25-34. Further, we examined the influence of racialized identity and region of childhood residence on these associations.

RESULTS

Higher cSES was associated with higher delayed recall and working memory scores across social positions. However, the strength of the association between higher cSES and working memory differed across racialized subgroups and region of childhood residence. We found a statistically significant three-way interaction between cSES, race and region of childhood residence. Of particular important, a small yet statistically robust association was found in all groups, but was especially strong among White Southerners and especially weak among Black participants from the South.

CONCLUSIONS

This study contributes to a growing body of research indicating that the protective effects of higher cSES on cognition are not universal across subgroups of intersecting social positions, consistent with the theory of MDR. These findings provide evidence for the importance of considering the role of systemic racism across geographic contexts as part of initiatives to promote equity in life course cognitive aging and brain health.

Utilizing maternal prenatal cognition as a predictor of newborn brain measures of intellectual development

Identifying reliable indicators of cognitive functioning prior to age five has been challenging. Prior studies have shown that maternal cognition, as indexed by intellectual quotient (IQ) and years of education, predict child intelligence at school age. We examined whether maternal full scale IQ, education, and inhibitory control (index of executive function) are associated with newborn brain measures and toddler language outcomes to assess potential indicators of early cognition. We hypothesized that maternal indices of cognition would be associated with brain areas implicated in intelligence in school-age children and adults in the newborn period. Thirty-seven pregnant women and their newborns underwent an MRI scan. T2-weighted images and surface-based morphometric analysis were used to compute local brain volumes in newborn infants. Maternal cognition indices were associated with local brain volumes for infants in the anterior and posterior cingulate, occipital lobe, and pre/postcentral gyrus - regions associated with IQ, executive function, or sensori-motor functions in children and adults. Maternal education and executive function, but not maternal intelligence, were associated with toddler language scores at 12 and 24 months. Newborn brain volumes did not predict language scores. Overall, the pre/postcentral gyrus and occipital lobe may be unique indicators of early intellectual development in the newborn period. Given that maternal executive function as measured by inhibitory control has robust associations with the newborn brain and is objective, brief, and easy to administer, it may be a useful predictor of early developmental and cognitive capacity for young children.

The Mediating Effects of Education and Occupational Complexity Between Race and Longitudinal Change in Late Life Cognition in ACTIVE

This study examined educational and occupational inequality as two aspects of social determinants of health that might mediate the longitudinal relationship between racialization and late life cognitive level and change. Participants were 2371 individuals racialized as Black and White from the ACTIVE study who provided occupational data. Data were analyzed from baseline and five assessments over 10-years using structural equation modeling. Black/White race served as the predictor, occupational complexity (OC) and years of education as mediators, and cognitive (memory, reasoning, and speed of processing) intercept, linear slope, and quadratic slope as the dependent variables. Black/White race showed significant indirect associations through education and OC on level of performance in cognition, linear change in reasoning and memory, and quadratic change in reasoning. Education and OC accounted for 11-16% of the association between race and cognitive level and represent modifiable social determinants of health that are associated with disparities in cognitive aging.

Social Mobility and Cognitive Impairment Among Korean Older Adults: Does Gender Matter?

The purpose of this study is to investigate the association between social mobility and cognitive impairment among older adults in Korea. The study sample is drawn from nationally representative data, which comes from the 2016 Korean Longitudinal Study of Ageing (KLoSA). The final sample consists of 4264 KLoSA respondents aged 65 or older. Gender-specific logistic regression models are used to examine the association between social mobility and cognitive impairment. The results show that, when compared to the reference group (stable low social mobility), women in the downward and the stable high social mobility groups were less likely to have cognitive impairment. In contrast, upward social mobility was a protective factor for cognitive impairment only among men. Gender-specific interventions may be needed to enhance cognitive health among older Koreans. Further research is needed to examine the causal relations between social mobility and cognitive health between the genders.

Early life adversity, race, and childhood socioeconomic status: intersecting drivers of later life cognition

OBJECTIVES

Research on associations between early life adversity (ELA) and later life cognition has yielded mixed results and generally have not considered how broader societal systems of stratification potentially influence associations. The current study addresses this gap by exploring if racialized identity and childhood socioeconomic status (cSES) moderate associations between ELA exposure and later life cognition.

METHODS

Using data from the Health and Retirement Study (Waves 2010-2018), we used growth curve modeling to examine if the confluence of ELA, cSES, and racialized identity is associated with cognition.

RESULTS

Among White participants, greater exposure to ELA was associated with poorer baseline cognitive functioning, and higher cSES buffered against this association. Among Black participants, exposure to ELA was not associated with baseline cognitive functioning, regardless of cSES. We did not find evidence of any associations between main predictors nor their interactions with change in cognition over time.

CONCLUSIONS

This study provides evidence that associations between ELA and later life cognition is contingent upon multiple social positions in the United States. These findings support the importance of integrating insights on intersecting social positions within life-course-oriented efforts to reduce racialized cognitive disparities.

Mechanisms underlying the association between adverse childhood experiences and racial disparities in later-life cognition

OBJECTIVE

Adverse childhood experiences (ACEs) may be a risk factor for later-life cognitive disorders such as dementia; however, few studies have investigated underlying mechanisms, such as cardiovascular health and depressive symptoms, in a health disparities framework.

METHOD

418 community-dwelling adults (50% nonHispanic Black, 50% nonHispanic White) aged 55+ from the Michigan Cognitive Aging Project retrospectively reported on nine ACEs. Baseline global cognition was a z-score composite of five factor scores from a comprehensive neuropsychological battery. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale. Cardiovascular health was operationalized through systolic blood pressure. A mediation model controlling for sociodemographics, childhood health, and childhood socioeconomic status estimated indirect effects of ACEs on global cognition via depressive symptoms and blood pressure. Racial differences were probed via t-tests and stratified models.

RESULTS

A negative indirect effect of ACEs on cognition was observed through depressive symptoms [β = -.040, 95% CI (-.067, -.017)], but not blood pressure, for the whole sample. Black participants reported more ACEs (Cohen's d = .21), reported more depressive symptoms (Cohen's d = .35), higher blood pressure (Cohen's d = .41), and lower cognitive scores (Cohen's d = 1.35) compared to White participants. In stratified models, there was a negative indirect effect through depressive symptoms for Black participants [β = -.074, 95% CI (-.128, -.029)] but not for White participants.

CONCLUSIONS

These results highlight the need to consider racially patterned contextual factors across the life course. Such factors could exacerbate the negative impact of ACEs and related mental health consequences and contribute to racial disparities in cognitive aging.

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

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

Evaluating cognitive and affective abilities among medical students: behavioural and medicolegal perspectives

Medical students attending university for the first time experience a new environment, full of significant social, cultural, and intellectual challenges. Moreover, drug abuse and bullying among university students are major global concerns. The aim of the current study was to assess the impact of medicolegal issues on undergraduate and postgraduate students. It is a cross-sectional survey-based study, with each set of questions investigating cognitive functions, aggression, personality, and exposure to medicolegal issues. Males and those with a chronic disease have been significantly exposed to medicolegal issues; exposed students were significantly older than nonexposed ones. The scores of aggression were significantly higher among exposed and male students. The cognitive scores were higher for the students from rural areas than in urban areas, and females were more neurotic than males. The current study recommends conducting campaigns to educate university students on the importance of formally disclosing unethical behaviors and listening to the victims to facilitate overcoming their negative feelings. As many victims feel comfortable disclosing victimization to their friends, we recommend conducting peer educational programs to help friends support their colleagues regarding unethical misconduct.

Lifecourse investigation of the cumulative impact of adversity on cognitive function in old age and the mediating role of mental health: longitudinal birth cohort study

OBJECTIVE

To investigate the accumulation of adversities (duration of exposure to any, economic, psychosocial) across the lifecourse (birth to 63 years) on cognitive function in older age, and the mediating role of mental health.

DESIGN

National birth cohort study.

SETTING

Great Britain.

PARTICIPANTS

5362 singleton births within marriage in England, Wales and Scotland born within 1 week of March 1946, of which 2131 completed at least 1 cognitive assessment.

MAIN OUTCOME MEASURES

Cognitive assessments included the Addenbrooke's Cognitive Examination-III, as a measure of cognitive state, processing speed (timed-letter search task), and verbal memory (word learning task) at 69 years. Scores were standardised to the analytical sample. Mental health at 60-64 years was assessed using the 28-item General Health Questionnaire, with scores standardised to the analytical sample.

RESULTS

After adjusting for sex, increased duration of exposure to any adversity was associated with decreased performance on cognitive state (β=-0.39; 95% CI -0.59 to -0.20) and verbal memory (β=-0.45; 95% CI -0.63 to -0.27) at 69 years, although these effects were attenuated after adjusting for further covariates (childhood cognition and emotional problems, educational attainment). Analyses by type of adversity revealed stronger associations from economic adversity to verbal memory (β=-0.54; 95% CI -0.70 to -0.39), with a small effect remaining even after adjusting for all covariates (β=-0.18; 95% CI -0.32 to -0.03), and weaker associations from psychosocial adversity. Causal mediation analyses found that mental health mediated all associations between duration of exposure to adversity (any, economic, psychosocial) and cognitive function, with around 15% of the total effect of economic adversity on verbal memory attributable to mental health.

CONCLUSIONS

Improving mental health among older adults has the potential to reduce cognitive impairments, as well as mitigate against some of the effect of lifecourse accumulation of adversity on cognitive performance in older age.

Effects of family income on brain functional connectivity in US children: associations with cognition

Higher family income (FI) is associated with larger cortical gray matter volume and improved cognitive performance in children. However, little is known about the effects of FI on brain functional and structural connectivity. This cross-sectional study investigates the effects of FI on brain connectivity and cognitive performance in 9- to 11-years old children (n = 8739) from the Adolescent Brain Cognitive Development (ABCD) study. Lower FI was associated with decreased global functional connectivity density (gFCD) in the default-mode network (DMN), inferior and superior parietal cortices and in posterior cerebellum, and increased gFCD in motor, auditory, and extrastriate visual areas, and in subcortical regions both for girls and boys. Findings demonstrated high reproducibility in Discovery and Reproducibility samples. Cognitive performance partially mediated the association between FI and DMN connectivity, whereas DMN connectivity did not mediate the association between FI and cognitive performance. In contrast, there was no significant association between FI and structural connectivity. Findings suggest that poor cognitive performance, which likely reflects multiple factors (genetic, nutritional, the level and quality of parental interactions, and educational exposure [1]), contributes to reduced DMN functional connectivity in children from low-income families. Follow-up studies are needed to help clarify if this leads to reductions in structural connectivity as these children age.

Effects of early-life environment and adulthood SES on cognitive change in a multiethnic cohort

OBJECTIVES

Early-life socioeconomic status (SES) and adversity are associated with late-life cognition and risk of dementia. We examined the association between early-life SES and adversity and late-life cross-sectional cognitive outcomes as well as global cognitive decline, hypothesizing that adulthood SES would mediate these associations.

METHODS

Our sample (N = 837) was a racially and ethnically diverse cohort of non-Hispanic/Latino White (48%), Black (27%), and Hispanic/Latino (19%) participants from Northern California. Participant addresses were geocoded to the level of the census tract, and US Census Tract 2010 variables (e.g., percent with high school diploma) were extracted and combined to create a neighborhood SES composite. We used multilevel latent variable models to estimate early-life (e.g., parental education, whether participant ever went hungry) and adult (participant's education, main occupation) SES factors and their associations with cross-sectional and longitudinal cognitive outcomes of episodic memory, semantic memory, executive function, and spatial ability.

RESULTS

Child and adult factors were strongly related to domain-specific cognitive intercepts (0.20-0.48 SD per SD of SES factor); in contrast, SES factors were not related to global cognitive change (0.001-0.01 SD per year per SD of SES factor). Adulthood SES mediated a large percentage (68-75%) of the total early-life effect on cognition.

CONCLUSIONS

Early-life sociocontextual factors are more strongly associated with cross-sectional late-life cognitive performance compared to cognitive change; this effect is largely mediated through associations with adulthood SES.

Links between early-life contextual factors and later-life cognition and the role of educational attainment

OBJECTIVE

Educational attainment is a well-documented predictor of later-life cognition, but less is known about upstream contextual factors. This study aimed to identify which early-life contextual factors uniquely predict later-life global cognition and whether educational attainment mediates these relationships.

METHOD

Participants were drawn from the Michigan Cognitive Aging Project (N = 485; Mage = 63.51; SDage = 3.13; 50% non-Hispanic Black). Early-life exposures included U.S. region of elementary school (Midwest, South, Northeast), average parental education, household composition (number of adults (1, 2, 3+), number of children), school racial demographics (predominantly White, predominantly Black, diverse), self-reported educational quality, and school type (public/private). Later-life global cognition was operationalized with a factor score derived from a comprehensive neuropsychological battery. Sequential mediation models controlling for sociodemographics estimated total, direct, and indirect effects of early-life contextual factors on cognition through educational attainment (years).

RESULTS

Higher educational quality, higher parental education, and attending a private school were each associated with better cognition; attending a predominantly Black or diverse school and reporting three or more adults in the household were associated with lower cognition. After accounting for educational attainment, associations remained for educational quality, school type, and reporting three or more adults in the household. Indirect effects through educational attainment were observed for school region, educational quality, school racial demographics, and parental education.

CONCLUSIONS

School factors appear to consistently predict later-life cognition more than household factors, highlighting the potential long-term benefits of school-level interventions for cognitive aging. Future research should consider additional mediators beyond educational attainment such as neighborhood resources and childhood adversity.

Association of primary lifetime occupational cognitive complexity and cognitive decline in a diverse cohort: Results from the KHANDLE study

INTRODUCTION

Higher occupational complexity has been linked to favorable cognitive outcomes, but rarely examined in racially and ethnically diverse populations.

METHODS

In a diverse cohort (n = 1536), linear mixed-effects models estimated associations between main lifetime occupational complexity and domain-specific cognitive decline (z-standardized). Occupational complexity with data, people, and things were classified using the Dictionary of Occupational Titles.

RESULTS

For occupational complexity with data, highest tertile (vs. lowest) was associated with higher baseline executive function (β = 0.11; 95% confidence interval [CI] 0.00-0.22) and slower annual rate of decline (β = 0.03; 95% CI 0.01-0.06), and higher baseline semantic memory (β = 0.14; 95% CI 0.04-0.25). Highest tertile of occupational complexity with people was associated with higher baseline executive function (β = 0.29; 95% CI 0.18-0.40), verbal episodic memory (β = 0.12; 95% CI 0.00-0.24), and semantic memory (β = 0.23; 95% CI 0.12-0.34).

DISCUSSION

In a diverse cohort, higher occupational complexity is associated with better cognition. Findings should be verified in larger cohorts.

HIGHLIGHT

Few studies have examined associations of occupational complexity with cognition in diverse populations. Racial and ethnic minorities are disproportionately exposed to lower occupational complexity. Occupational complexity with data and people are associated with better cognition.

Is Stress an Overlooked Risk Factor for Dementia? A Systematic Review from a Lifespan Developmental Perspective

Stress exposure and stress reactivity may be potent factors associated with increased risk of dementia. The 2017 Lancet Commission on Dementia and its 2020 update reviewed modifiable risk factors associated with dementia, but stress was not addressed directly. The present study provides a focused review of the association between stress and dementia across the lifespan, with measures of stress including stress exposure, psychological stress, posttraumatic stress disorder (PTSD), and biological markers of stress. Published research articles were identified in the American Psychological Association PsycINFO database (1887-2021), Web of Science database, and Google Scholar. A total of 53 samples from 40 studies published from 1985 to 2020 met inclusion criteria. Results suggest that stressful life events that occur earlier in the lifespan, such as loss of a parent, psychological stress experienced in midlife, and extreme stress responses, i.e., PTSD, correlate with higher risk of dementia. Although results generally are mixed, a consistent theme is that stress experienced earlier in the lifespan and chronic stress portend the greatest risk of dementia. Reducing stress exposure and improving stress management when stress exposure cannot be changed are thus relevant strategies in dementia risk reduction.

Gender, Personality, and Cognitive Resilience Against Early-Life Disadvantage

OBJECTIVES

Early-life disadvantage (ELD) relates to lower late-life cognition. However, personality factors, including having an internal locus of control (LOC) or a conscientious personality, relate to resilience and effective stress coping. We explore whether personality factors convey resilience against the negative effects of ELD on cognition, by gender, in Mexico.

METHODS

Using the 2015 Mexican Health and Aging Study, we estimated expected cognition using multiple ELD markers to identify a subsample in the lowest quartile of expected cognition given ELD (n = 2,086). In this subsample, we estimated cross-sectional associations between personality and having above-median observed cognitive ability (n = 522) using logistic regression.

RESULTS

Among those in the lowest quartile of expected cognition, a more internal LOC (β = 0.32 [men] and β = 0.44 [women]) and conscientious personality (β = 0.39 [men] and β = 0.17 [women]) were significantly associated with having above-median cognitive ability in models adjusted for demographic confounders. Larger benefits of conscientiousness were observed for men than women. Associations between personality and having above-median cognitive ability remained statistically significant after further adjustment for health, stress, and cognitive stimulation variables, regardless of gender.

DISCUSSION

Personality factors may convey resilience among individuals who experienced ELD, potentially breaking the link between ELD and worse late-life cognition. Structural factors and gender roles may affect how much women benefit from personality factors.

Cognitive dysfunction in patients with childhood-onset systemic lupus erythematosus may impact treatment

BACKGROUND

Cognitive dysfunction (CD) is a widespread manifestation in adult systemic lupus erythematosus (SLE) patients, but this subject is rarely examined in patients with childhood-onset SLE (cSLE). This study aimed to assess the frequency of CD, its associations with lupus clinical manifestations and its impact on the health-related quality of life (HRQL) in young adult cSLE patients.

METHODS

We evaluated 39 cSLE patients older than 18 years. They underwent a rheumatologic evaluation and extensive neuropsychological assessment, encompassing all cognitive domains described by the American College of Rheumatology. HRQL was assessed with the WHOOQOL-BREEF, General Activities of Daily Living Scale (GADL) and Systemic Lupus Erythematosus-specific quality-of-life instrument (SLEQOL). The activity of SLE was evaluated with the modified sle disease activity index (sledai-2k).

RESULTS

Impairment in at least one cognitive domain was found in 35 (87.2%) patients. The most compromised domains were attention (64.1%), memory (46.2%), and executive functions (38.5%). Patients with cognitive impairment were older, had more accumulated damage and had worse socioeconomic status. Regarding the association between cognitive dysfunction and HRQL, memory impairment was correlated with worse environmental perception and a worse relationship with the treatment.

CONCLUSION

In this study, the frequency of CD in cSLE patients was as high as that in the adult SLE population. CD can significantly impact the response of cSLE patients to treatment, justifying preventive measures in the care of this population.

Leisure activities and cognitive impairment in old age: The role of life course socioeconomic status

In the current literature on cognitive function, life course socioeconomic status (SES) and engaging in leisure activities are often viewed as parallel measures of cognitive reserve that independently affect cognitive impairment in old age. Some studies also suggest that leisure activity mediates the effect of SES on cognitive impairment. What is less examined is the modification effect of SES on the association between engaging in leisure activities and cognitive impairment, especially from a life course perspective. In this study, we focus on the interaction effects of specific measures of SES and leisure activities on cognitive impairment. We use data from the Chinese Longitudinal Healthy Longevity Survey, which includes five waves of interviews with adults aged 65 and older between 2002 and 2014. Cognitive impairment is measured by the Chinese version of the Mini-Mental Status Examination. Childhood and adulthood SES and participation in seven leisure activities are included in this analysis. We adopt a lagged independent variable approach and the Generalized Linear Mixed Model to conduct the analysis. Findings confirm that higher SES in both childhood and adulthood are associated with low levels of cognitive impairment in the older Chinese population. Furthermore, there are significant interaction effects between specific life course SES and leisure activities with a consistent pattern: Those of higher life course SES enjoy extra benefits from engaging in leisure activities. The findings point to a modification mechanism that connects life course SES, leisure activities, and cognitive health inequality among older adults.

20th Century Puerto Rico and Later-Life Health: The Association Between Multigenerational Education and Chronic Conditions in Island-Dwelling Older Adults

OBJECTIVES

Previous research on the association between education and older adult health in the U.S. has not included Puerto Rico. We investigated the effects of multigenerational educational attainment and chronic conditions among older Puerto Ricans residing on the archipelago's main island.

METHODS

Data were from the longitudinal Puerto Rican Elderly Health Conditions Project. Generalized Poisson regression models were used to examine if multigenerational educational attainment was associated with chronic disease.

RESULTS

Findings show that parental educational attainment was associated with fewer chronic conditions among females at baseline but not at follow-up, suggesting that the effects of parental education on health over time are less pronounced. For males, educational attainment across the three generations was not significantly associated with chronic disease at baseline or follow-up.

DISCUSSION

Multigenerational education is an important determinant of older adult health that continues to be relevant in Puerto Rico and the Latin American and Hispanic-Caribbean region.

Socioeconomic Status, Biological Aging, and Memory in a Diverse National Sample of Older US Men and Women

BACKGROUND AND OBJECTIVES

Exposure to socioeconomic disadvantage is associated with early-onset cognitive aging. Biological aging, the progressive loss of system integrity that occurs as we age, is proposed as a modifiable process mediating this health inequality. We examined whether socioeconomic disparities in cognitive aging in mid-to late-life adults is explained by accelerated biological aging similarly across race, ethnicity, and sex/gender.

METHODS

Data were from a prospective cohort study of the US Health and Retirement Study DNA methylation substudy. Socioeconomic status (SES) was measured from years of education and household wealth at baseline. The extent and pace of biological aging were quantified using 3 DNA methylation measures: PhenoAge, GrimAge, and DunedinPoAm. Cognitive aging was measured from repeated longitudinal assessments of immediate and delayed word recall. Latent growth curve modeling estimated participants' level of memory performance and rate of decline over 2-11 follow-up assessments spanning 2-20 years. Multiple-group models were estimated to assess whether the relationship between SES and memory trajectories was mediated by biological aging across racial-ethnic by sex/gender subgroups.

RESULTS

Data from a total of 3,997 adults aged 50-100 years were analyzed. Participants with lower SES had a lower memory performance, had a faster decline, and exhibited accelerated biological aging (SES effect size associations [β] ranged from 0.08 to 0.41). Accelerated biological aging was associated with decreased memory performance and faster memory decline (effect size range 0.03-0.23). SES-biological aging associations were the strongest for White men and women and weakest for Latinx women. The relationship between biological aging measures and memory was weaker for Black participants compared with that for White and Latinx people. In mediation analysis, biological aging accounted for 4%-27% of the SES-memory gradient in White participants. There was little evidence of mediation in Black or Latinx participants.

DISCUSSION

Among a national sample of mid-to late-life adults, DNA methylation measures of biological aging were variably associated with memory trajectories and SES across White, Black, and Latinx mid-to late-life adults. These results challenge the assumption that DNA methylation biomarkers of aging that were developed in primarily White people can equivalently quantify aging processes affecting cognition in Black and Latinx mid-to late-life adults.

Direct and indirect associations between childhood socioeconomic status and cognitive function in the middle-aged and older adults in China

OBJECTIVES

To investigate whether childhood socioeconomic status (SES) is associated with cognitive function, and what factors might mediate the associations.

METHOD

Using data from the China Health and Retirement Longitudinal Study (CHARLS) and within frameworks of the latency model, the pathway model and the accumulation model, we quantified direct and indirect pathways between childhood SES and cognitive function for Chinese middle-aged and older adults aged 45+ by structural equations modeling.

RESULTS

We found significant direct, indirect and total effects of childhood SES on cognitive function at baseline. The indirect effects were mediated through educational attainment, household consumption, smoking behaviors and social engagement. At follow-ups, cognitive enhancement can be made by indirect pathways through educational attainment, improvement of household consumption and social engagement.

CONCLUSION

Our results supported the latency model, the pathway model and the accumulation model when considering pathways linking childhood SES to cognitive function. The findings underscored the value of taking early interventions to improve SES and cognitive function, especially among those with low childhood SES.

Black-White variation in the relationship between early educational experiences and trajectories of cognitive function among US-born older adults

Black adults face a substantially higher risk for dementia in later life compared to their White peers. Given the critical role of educational attainment and cognitive function in later life dementia risk, this paper aims to determine if early educational experiences and educational attainment are differentially related to trajectories of cognitive status across race and if this further varies by education cohort. We use data from the Life History Mail Survey (LHMS) and prospective data on cognition from the Health and Retirement Study (HRS). We restrict our sample to Black and White US-born adults who provided at least one measure of cognitive status from 1995/6–2016. We find evidence of Black-White differences in the association between educational experiences and level of cognitive function, episodic memory, and working memory, but little evidence of Black-White differences in these associations with decline. Having a learning problem was associated with lower levels of cognitive function, episodic memory, and working memory for White and Black older adults, but was more strongly related to these outcomes among Black older adults. Further, the Black-White difference in this association was generally found in older cohorts that completed schooling after enactment of federal policies that improved educational resources for children with learning disabilities. Attending racially discordant schools was positively associated with level of these cognitive outcomes for Black older adults but not for White older adults. We also find that the educational gradient in level of cognitive function was larger for Black compared to White older adults in older cohorts not benefiting from the Brown v Board of Education decision but was similar for Black and White older adults attending school in the post-Brown era.

•

Black adults are twice as likely to have dementia than White adults.

•

The roots of this risk are poorly understood but may be due to educational experiences.

•

Three educational experiences differentially predicted cognitive status by race.

•

These included having a learning problem, desegregated schooling, and attainment.

Job demands may determine cognitive and physical aging after retirement

During adulthood, we spend most of our time and efforts at work. However, the impact of employment in aging is poorly explored. Our study addressed how job demands can affect aging after retirement. We have developed a descriptive observational study carried out in 367 older adults with a mean age of 73.9 years (66.5% women and 33.5% men), measuring cognition and functional status. Our results demonstrate that older adults who had high mental demands in their jobs, show better scores in cognition. However, they show poor functional development of basic and instrumental activities of daily life (p< .05). In contrast, former workers who had high physical demands, display lower scores in cognition and lower functional performance in instrumental activities (p< .05). Work life activities contribute to cognitive and physical decline after retirement. Therefore, healthy aging should include interventions that consider the job influence on the age impairment.

Associations between childhood maltreatment and educational, health and economic outcomes among middle-aged Chinese: The moderating role of relative poverty

BACKGROUND

Despite substantial evidence in developed countries showing that child maltreatment can lead to serious life-long consequences, relatively few studies so far have examined the associations between childhood maltreatment and adulthood outcomes in developing countries, such as China. It also remains unclear as to the impact of relative poverty on the long-term development of maltreated children.

OBJECTIVE

This study aims to investigate the associations between childhood maltreatment and educational, health, and economic outcomes among middle-aged Chinese, as well as explore the moderating effects of relative poverty.

PARTICIPANTS AND SETTING

The participants of this study were the middle-aged respondents (aged 45 to 59) in the 2011, 2013, and 2015 China Health and Retirement Longitudinal Studies (CHARLS) and the CHARLS Life History Survey (N = 24,114).

METHODS

Physical abuse and emotional neglect were measured to investigate childhood maltreatment. Subjective and objective indicators were used to examine relative poverty. A broad range of midlife outcomes were explored, including educational attainment, physical health, mental health, cognitive functions, labor force participation, wage expenditure, and financial strain. Data analyses were conducted using fixed effects model for panel data and a propensity score matching approach.

RESULTS

Childhood physical abuse and emotional neglect were both significantly associated with lower levels of midlife educational attainment, cognitive functions, individual wages, and household expenditures, as well as higher rates of chronic diseases, depressive symptoms, poverty, and welfare involvement. Childhood physical abuse also predicted higher risks of difficulty performing the activities of daily living (ADL), unemployment, and fewer work hours. Early-life exposure to relative poverty was linked to a greater likelihood of childhood maltreatment and mid-life adversities. It further aggravated the negative impacts of childhood maltreatment on middle-age outcomes.

CONCLUSION

Child maltreatment had a profound effect on long-term child development and midlife outcomes in Chinese contexts. Relative poverty in early life was a moderator that exacerbated the outcomes associated with childhood maltreatment.

Childhood deprivations predict late-life cognitive impairment among older adults in India

Large population-based studies on the associations of childhood factors with late-life cognition are lacking in many low and middle income countries including India. In this study, we assessed the prevalence of late-life cognitive impairment and examined the associations of childhood socioeconomic status (SES) and health conditions with cognitive impairment among older adults in India. Data for this study were derived from the Longitudinal Ageing Study in India conducted in 2017–18. The effective sample size was 31,464 older adults aged 60 years and above. Cognitive functioning was measured through five global domains (memory, orientation, arithmetic function, executive function, and object naming). The overall score ranged between 0 and 43, and the score was reversed indicating cognitive impairment. Descriptive statistics along with mean scores of cognitive impairment were presented. Additionally, moderated multivariable linear regression models were employed to examine the association between explanatory variables, including childhood SES and health conditions and late-life cognitive impairment. The mean score of cognitive functioning among the study participants was 21.72 (CI 2.64–21.80). About 15% of older adults had poor health conditions, and 44% had lower financial status during their childhood. Older adults who had a fair health during their childhood were more likely to suffer from cognitive impairment in comparison to older adults who had good health during their childhood (Coef: 0.60; CI 0.39, 0.81). In comparison to older adults who had good childhood financial status, those who had poor childhood financial status were more likely to suffer from cognitive impairment (Coef: 0.81; CI 0.56, 1.07). Older adults who had fair childhood health status and poor childhood financial status were more likely to suffer from cognitive impairment in comparison to older adults who had good childhood health and good financial status (Coef: 1.26; CI 0.86, 1.66). Social policies such as improving educational and financial resources in disadvantaged communities and socioeconomically poor children and their families, would help to enhance a better cognitive ageing and a healthy and dignified life in old age.

Paternal Occupation and Delirium Risk in Older Adults: A Potential Marker of Early-Life Exposures

Background and Objectives

Delirium is a common disorder among older adults following hospitalization or major surgery. Whereas many studies examine the risk of proximate exposures and comorbidities, little is known about pathways linking childhood exposures to later-life delirium. In this study, we explored the association between paternal occupation and delirium risk.

Research Design and Methods

A prospective observational cohort study of 528 older adults undergoing elective surgery at two academic medical centers. Paternal occupation group (white collar vs. blue collar) served as our independent variable. Delirium incidence was assessed using the Confusion Assessment Method (CAM) supplemented by medical chart review. Delirium severity was measured using the peak CAM-Severity score (CAM-S Peak), the highest value of CAM-S observed throughout the hospital stay.

Results

Blue-collar paternal occupation was significantly associated with a higher rate of incident delirium (91/234, 39%) compared with white-collar paternal occupation (84/294, 29%), adjusted odds ratio OR (95% confidence interval [CI]) = 1.6 (1.1, 2.3). All analyses were adjusted for participant age, race, gender, and Charlson Comorbidity Index. Blue-collar paternal occupation was also associated with greater delirium severity, with a mean score (SD) of 4.4 (3.3), compared with white-collar paternal occupation with a mean score (SD) of 3.5 (2.8). Among participants reporting blue-collar paternal occupation, we observed an adjusted mean difference of 0.86 (95% CI = 0.4, 1.4) additional severity units.

Discussion and Implications

Blue-collar paternal occupation is associated with greater delirium incidence and severity, after adjustment for covariates. These findings support the application of a life-course framework to evaluate the risk of later-life delirium and delirium severity. Our results also demonstrate the importance of considering childhood exposures, which may be consequential even decades later.

The intersectionality of life course socioeconomic status, race, and cognitive decline: An 18-year follow-up

OBJECTIVES

Studies have documented the impact of childhood socioeconomic status (SES) on cognition. However, research that simultaneously considers SES in varied life stages, the multidimensional mechanisms, and racial differences is relatively understudied. This study examines the intersectionality across age, SES, and race and its impact on cognitive trajectories.

METHODS

Using 8376 respondents aged 65+ from the 1998-2016 Health and Retirement Study, we used latent growth curve modeling to examine the effects of four life course models (latency, pathway, accumulation, and mobility) on 18-year trajectories of mental status and episodic memory. We further tested for differences in the links between SES and cognitive trajectories between black and white respondents.

RESULTS

Cognitive function declines with age and is interrelated with SES and race. Adulthood has a stronger effect on cognitive performance than childhood. However, linked positive childhood and adulthood SES contributes to positive cognition. Accumulated SES disadvantages were associated with lower cognition. Older adults with downward mobility and low SES throughout their lifespans had the lowest cognition scores. Life course models operated differently on trajectories of cognitive decline, yet the effects were particularly evident among older black respondents. Overall, those with socioeconomic advantages tended to have a slower decline in cognition, while a faster decline occurred for those with accrued disadvantages.

CONCLUSIONS

Cognitive performance is a complex, longitudinal process intertwined with socioeconomic conditions and population heterogeneity shaped by life course contexts. Policies that facilitate healthy cognitive performance and address SES inequality could equalize health opportunities and address racial cognitive disparities later in life.

Retrospective reports of socioeconomic disadvantage in childhood and mortality risk: are associations consistent across measures and sex?

Although prior research has established associations between childhood socioeconomic disadvantage and all-cause mortality, there is still limited research investigating (1) the consistency between subjective and objective reports of childhood socioeconomic status, (2) sex differences in the associations between childhood socioeconomic disadvantage and all-cause mortality, and (3) potential mediators within these associations. Drawing on data from the Midlife in the United States (MIDUS) cohort (N = 7425), we examined the associations between three distinct indicators of childhood socioeconomic disadvantage and all-cause mortality risk, and whether these associations differ for males and females. Among males only, lower perceived relative childhood financial status, lower levels of parents' education, and receipt of welfare during childhood were associated with excess mortality risk, adjusted for age and minority status, with adjusted hazard ratios ranging from 1.24 (95% confidence interval (CI): 1.02, 1.51) for perceived childhood financial status to 1.28 (95% CI: 1.11, 1.47) for welfare in childhood. When additionally adjusted for education, substance use, depression, and underlying health conditions, only childhood welfare status maintained an association with mortality (AHR, 1.17; 95% CI, 1.02-1.35). Mediation analyses among males revealed that education, substance use, depression, and underlying health conditions accounted for substantial proportions of these associations, ranging from 31.03 to 57.63%, across indicators of childhood socioeconomic disadvantage. Future research is needed to clarify the developmental mechanisms that lead to sex differences and identify effective strategies to intervene on the relation between childhood socioeconomic position and excess mortality risk among males.

Establishing a Framework for Gathering Structural and Social Determinants of Health in Alzheimer's Disease Research Centers

Structural and social determinants of health (SSDoH) are environmental conditions in which individuals are born, live, learn, work, play, worship, and age that affect health, functioning, and quality-of-life outcomes across the life course. Growing evidence suggests that SSDoH can help to explain heterogeneity in outcomes in Alzheimer's disease and Alzheimer's disease and related dementias (AD/ADRD) research and clinical practice. The National Institute on Aging has prioritized collecting SSDoH data to elucidate disease mechanisms and aid discovery of disease-modifying treatments. However, a major nexus of AD/ADRD research, the national network of Alzheimer's Disease Research Centers (ADRCs), collects few SSDoH data. We describe a framework for feasibly gathering and modeling SSDoH data across ADRCs. We lay out key constructs, their measures, and empirical evidence for their importance in elucidating disease and prevention mechanisms. Toward a goal of translation, the framework proposes a modular structure with a core set of measures and options for adjunctive modules. We describe considerations for measuring SSDoH in existing geographically and culturally diverse research cohorts. We also outline a rationale for universal implementation of a set of SSDoH measures and juxtapose the approach with alternatives aimed at collecting SSDoH data.

Childhood Socioeconomic Disadvantage and Pathways to Memory Performance in Mid to Late Adulthood: What Matters Most?

OBJECTIVES

Childhood socioeconomic disadvantage is consistently associated with lower cognitive function in later life. This study aims to distinguish the contribution of specific aspects of childhood socioeconomic disadvantage for memory performance in mid-to-late adulthood, with consideration for direct and indirect effects through education and occupation.

METHODS

Data were from adults aged 50-80 years who completed the life history module in the 2006/07 wave of the English Longitudinal Study of Ageing (n=4,553). The outcome, memory score, was based on word recall tests (range: 0-20 points). We used the g-formula to estimate direct and indirect effects of a composite variable for childhood socioeconomic disadvantage, and its four individual components: lower-skilled occupation of the primary breadwinner, having few books in the home, overcrowding in the home, and lack of water and heating facilities in the home.

RESULTS

Few books were the most consequential component of childhood socioeconomic disadvantage for later life memory (total effect: ⎼0.82 points for few books; 95% CI: ⎼1.04, ⎼0.60), with roughly half being a direct effect. The total effect of a breadwinner in lower-skilled occupations was smaller but not significantly different from few books (⎼0.67 points; 95% CI: ⎼0.88, ⎼0.46), while it was significantly smaller with overcrowding (⎼0.31 points; 95% CI: ⎼0.56, ⎼0.06). The latter two total effects were mostly mediated by education and occupation.

DISCUSSION

A literate environment in the childhood home may have lasting direct effects on memory function in mid-to-later life, while parental occupation and overcrowding appear to influence memory primarily through educational and occupational pathways.

Intergenerational Socioeconomic Mobility and Cognitive Impairment Among Chinese Older Adults: Gender Differences

This study examined the impact of intergenerational socioeconomic mobility on the risk of cognitive impairment in a cohort of Chinese older adults aged 60 years and older. Data were derived from the 2014 wave of the Chinese Longitudinal Healthy Longevity Survey. Logistic regression models were performed to assess the impact of three dimensions of socioeconomic mobility (occupational mobility, educational mobility, and residential mobility) on the risk of cognitive impairment. We found that men who were stable with non-professional jobs across generations had a higher risk of cognitive impairment than their counterparts who experienced upward occupational mobility compared to their father. This pattern was not observed in women. There was little evidence that educational mobility or residential mobility affected cognitive impairment in later life. The findings have implications for advancing supportive policies and practices related to maximizing the benefits of education and career advancements for cognition in later life.

Race, Childhood Socioeconomic Status, and Region of Childhood Residence as Intersectional Life Course Predictors of Cognitive Aging in the U.S

Background and Objectives

Race, childhood socioeconomic status (cSES), and region of childhood residence are each associated with later life cognition, but no studies have examined how the confluence of these factors influence later life cognitive performance. Guided by intersectionality theory, we examined individuals’ social positionality across these dimensions as a predictor of cognitive performance in later life among non-Hispanic White (NHW) and Black (NHB) older adults.

Research Design and Methods

We used data from the 2010-2016 waves of the Health and Retirement Study (HRS) with participants ages 65 and older in 2010. We employed growth curve modeling to estimate associations among race, cSES and region of childhood residence, as well as their interactions, and cognitive performance at baseline and over time.

Results

Identifying as NHB, residing in the South, and having lower cSES each were associated with poorer later life cognition at baseline. Childhood residence in the South was an especially strong risk factor for poorer cognition among NHBs. Among NHWs, higher cSES was associated with better baseline cognitive performance, especially among those from the South. NHBs from the South demonstrated a small advantage of higher cSES, but regardless of cSES, NHBs from the South had lower levels of baseline cognitive scores compared to all other subgroups. We found that Southern childhood residence predicted faster rates of change in over a 6-year period.

Discussion and Implications

Our findings suggest that intersectional social positions across race, cSES, and region of childhood residence primarily influence baseline cognition in later life. Results implicate the importance of attention to multiple social positions in the context of racism within social policies and other initiatives to promote equity in life course brain health.

Effect of childhood proximity to lead mining on late life cognition

INTRODUCTION

Lead exposure negatively affects cognitive functioning among children. However, there is limited evidence about whether exposure to lead in early life impairs later life cognitive functioning.

METHODS

Participants in the prospective Wisconsin Longitudinal Study cohort (N = 8583) were linked to the 1940 Census, which was taken when they were young children. We estimated the effect of living near a lead mine in childhood on late life memory/attention and language/executive function in 2004 (mean age 64) and 2011 (mean age 71).

RESULTS

Lead-exposed children had significantly steeper memory/attention decline between 2004 and 2011 and worse language/executive function at baseline in late life. These long-term effects of lead were not mediated through adolescent IQ or late life SES and health factors.

DISCUSSION

Proximity to lead mining in childhood had long-term effects on late life memory/attention decline and language/executive function, reflecting a possible latent influence of lead exposure. More research is needed to understand behavioral and biological pathways underlying this relationship.

Using sibling models to unpack the relationship between education and cognitive functioning in later life

As the population ages and the prevalence of dementia increases, unpacking robust and persistent associations between educational attainment and later life cognitive functioning is increasingly important. We do know, from studies with robust causal designs, that policies that increase years of schooling improve later life cognitive functioning. Yet these studies don't illuminate why older adults with greater educational attainment have relatively preserved cognitive functioning. Studies focused on why, however, have been hampered by methodological limitations and inattention to some key explanations for this relationship. Consequently, we test explanations encompassing antecedent factors, specifically family environments, adolescent IQ, and genetic factors, as well as adult mediating mechanisms, specifically health behaviors and health. We employ the Wisconsin Longitudinal Study, which includes 80 years of prospectively collected data on a sample of 1 in every 3 high school graduates, and a selected sibling, from the class of 1957. Sibling models, and the inclusion of prospectively collected early and midlife covariates, allows us to address the explanatory and methodological limitations of the prior literature to better unpack the relationship between education and later life cognitive functioning. We find little evidence that early life genetic endowments and environments, or midlife health and health behaviors, explain the relationship. Adolescent cognition, however, does matter; higher educational attainment, linked to antecedent adolescent cognitive functioning, helps protect against lower levels of cognitive functioning in later life. Both adolescent cognition and education, however, independently associate with later life cognitive functioning at relatively similar magnitudes. Educational attainment's relationship to later life cognitive functioning is not simply a function of adolescent cognitive functioning.

Life course linkages between enriching early-life activities and later life cognition: Evidence from the Wisconsin Longitudinal Study

Prior research suggests that participation in enriching early-life activities (EELAs) has long-term benefits for cognitive health and aging. This study aims to examine the life course processes underlying these associations by drawing on theoretical models from life course epidemiology. Specifically, we tested sensitive-period effects, social pathways, and selection effects as potential explanations for linkages between greater participation in EELAs and better later life cognition. We drew on data from the Wisconsin Longitudinal Study (WLS), which is among the longest-running cohort studies in the U.S. that has followed graduates (all identified as non-Hispanic White) from Wisconsin high schools since 1957. We used prospective measures of key variables, including information from high school yearbooks, with assessments of cognitive performance at ages 65 and 72. Results from multilevel modeling indicated that greater participation in cognitively oriented extracurricular activities (but not physically nor socially oriented activities) was associated with both better language/executive functioning and memory at age 65. Although the size of these associations was reduced when accounting for other cognitive resources in adolescence (childhood socioeconomic status and adolescent cognitive ability) and in midlife (adult socioeconomic status and formal group participation), there remained small, yet statistically robust, associations. We did not find robust associations between greater EELA engagement and slower rates of decline in cognition between ages 65 and 72, nor did we find evidence of gender differences. Results suggest that for this cohort of older adults, EELA participation is part of life course "protective chains," whereby exposures to assets at one point in the life course increase the likelihood of subsequent exposures, each sequentially and in their own right, toward better later life cognition. We discuss how results support the importance of policies and practices to promote healthy cognitive development among youth for the long-term cognitive health of a rapidly aging U.S. population.

Adverse Childhood Experiences and Mild Cognitive Impairment in Later Life: Exploring Rural/Urban and Gender Differences Using CHARLS

This paper aims to examine whether and how adverse childhood experiences are associated with mild cognitive impairment among middle-aged and older adults in China, and if the associations vary by gender and rural/urban residence. Using four waves of data from the China Health and Retirement Longitudinal Study, cox proportional hazard models were applied. Results showed that the rural and female subsamples were significantly disadvantaged and were more likely to be cognitively impaired. Moreover, childhood family socioeconomic status and childhood social relationships were significantly associated with the risk of mild cognitive impairment for the study sample. Our findings suggest that, for middle-aged and older Chinese adults, adverse childhood experiences could have long-lasting impacts on cognitive functioning throughout the life course.

Promoting brain health through physical activity among adults exposed to early life adversity: Potential mechanisms and theoretical framework

Adverse childhood experiences such as abuse, neglect, and poverty, profoundly alter neurobehavioral development in a manner that negatively impacts health across the lifespan. Adults who have been exposed to such adversities exhibit premature and more severe age-related declines in brain health. Unfortunately, it remains unclear whether the negative effects of early life adversity (ELA) on brain health can be remediated through intervention in adulthood. Physical activity may represent a low-cost behavioral approach to address the long-term consequences of ELA on brain health. However, there has been limited research examining the impact of physical activity on brain health among adults with a history of ELA. Accordingly, the purpose of this review is to (1) review the influence of ELA on brain health in adulthood and (2) highlight evidence for the role of neurotrophic factors, hypothalamic-adrenal-pituitary axis regulation, inflammatory processes, and epigenetic modifications in mediating the effects of both ELA and physical activity on brain health outcomes in adulthood. We then propose a theoretical framework to guide future research in this area.

Pathways from early life SES to dementia risk in old age: The role of personality

OBJECTIVE

This study investigates the association between childhood socioeconomic status (cSES) and risk of cognitive impairment in older adulthood, and whether Five Factor Model personality traits mediated this association.

METHODS

A sample of 9,995 participants (mean age = 67.01 years) from the Health and Retirement Study were followed every two years from 2006 to 2018. cSES was tested as a predictor of risk of dementia and risk of cognitive impairment not dementia (CIND). Personality was tested as a mediator of these associations. Models were adjusted for age, gender, ethnicity, race, education, and baseline year.

RESULTS

Although effect sizes were modest, results indicated that lower cSES was associated with higher risk of dementia (HR=0.88, [0.775, 0.985]). Higher cSES was also associated with higher Conscientiousness and lower Neuroticism. Conscientiousness and Neuroticism each accounted for 7.9% of the total effect of cSES on dementia. Results were similar for CIND.

CONCLUSIONS

Early childhood socioeconomic factors may contribute to cognitive impairment in older adulthood, an association mediated, in part, through adult personality traits.

Trans-ethnic Meta-analysis of Interactions between Genetics and Early Life Socioeconomic Context on Memory Performance and Decline in Older Americans

Later life cognitive function is influenced by genetics as well as early- and later-life socioeconomic context. However, few studies have examined the interaction between genetics and early childhood factors. Using gene-based tests (iSKAT/iSKAT-O), we examined whether common and/or rare exonic variants in 39 gene regions previously associated with cognitive performance, dementia, and related traits had an interaction with childhood socioeconomic context (parental education and financial strain) on memory performance or decline in European ancestry (EA, N=10,468) and African ancestry (AA, N=2,252) participants from the Health and Retirement Study. Of the 39 genes, 22 in EA and 19 in AA had nominally significant interactions with at least one childhood socioeconomic measure on memory performance and/or decline; however, all but one (father's education by SLC24A4 in AA) were not significant after multiple testing correction (FDR <0.05). In trans-ethnic meta-analysis, two genes interacted with childhood socioeconomic context (FDR <0.05): mother's education by MS4A4A on memory performance, and father's education by SLC24A4 on memory decline. Both interactions remained significant (p<0.05) after adjusting for respondent's own educational attainment, APOE ε4 status, lifestyle factors, BMI, and comorbidities. For both interactions in EA and AA, the genetic effect was stronger in participants with low parental education. Examination of common and rare variants in genes discovered through GWAS shows that childhood context may interact with key gene regions to jointly impact later life memory function and decline. Genetic effects may be more salient for those with lower childhood socioeconomic status.

Cognition in context: Pathways and compound risk in a sample of US non-Hispanic whites

The population of individuals with cognitive impairment and dementia is growing rapidly, necessitating etiological investigation. It is clear that individual differences in cognition later in life have both genetic and multi-level environmental correlates. Despite significant recent progress in cellular and molecular research, the exact mechanisms linking genes, brains, and cognition remain elusive. In relation to cognition, it is unlikely that genetic and environmental risk factors function in a vacuum, but rather interact and cluster together. The purpose of the present study was to examine whether aspects of individual socioeconomic status (SES) explain the cognitive genotype-phenotype association, and whether neighborhood SES modifies the effects of genes and individual SES on cognitive ability. Using data from non-Hispanic White participants in the 2016 wave of the Health and Retirement Study, a national sample of United States adults, we examined links between a polygenic score for general cognition and performance-based cognitive functioning. In a series of weighted linear regressions and formal tests of mediation, we observed a significant genotype-phenotype association that was partially attenuated after including individual education to the baseline model, although little reductions were observed for household wealth or census tract-level percent poverty. These findings suggest that genetic risk for poor cognition is partially explained by education, and this pathway is not modified by poverty-level of the neighborhood.

Objective and subjective childhood socioeconomic disadvantage and incident depression in adulthood: a longitudinal analysis in the Sister Study

Understanding of the role of objective versus subjective childhood socioeconomic disadvantage (SD) in depression onset in adulthood among women, independent of later life SD, and across birth cohorts, is limited. We examined the association between objective (i.e., household education level) and subjective (i.e., rank of family income and report of not enough food to eat) SD during childhood and diagnosis of clinical depression after age 30 among 47,055 women in the Sister Study. We used Cox proportional hazard models adjusting for women's race/ethnicity, childhood household composition, mother's age at her birth adulthood educational attainment, and calendar year of birth. Analyses were repeated stratified by 10-year birth group. A total of 8036 (17.1%) women were diagnosed with clinical depression over a mean follow-up of 24.0 (± 9.9) years. Those reporting being poor (versus well-off) or not having enough food to eat in childhood had a 1.28 (95% confidence interval (CI) 1.13, 1.44) and 1.30 (95% CI 1.21, 1.41) times higher rate of depression diagnosis, respectively, with consistent associations observed across birth year groups. An inverse association between low household education level and incident depression was observed at baseline (i.e., age 30) becoming positive over time in the total sample but only among women born between 1935-1954 in analyses stratified by 10-year birth group. Our findings suggest that subjective SD in childhood is a largely consistent predictor of depression onset among women in adulthood whereas the effects of household education level in childhood may vary across women born into different birth cohorts, and for some, across the lifecourse.

Musical instrument engagement across the life course and episodic memory in late life: An analysis of 60 years of longitudinal data from the Wisconsin Longitudinal Study

Background

As the global burden of dementia increases, the absence of treatment underscores the need for identification of factors that may improve cognitive reserve–the ability to stave off cognitive decline in old age. The beneficial association between musical instrument engagement and episodic memory has been identified in children, young adults, and older adults. Yet, previous studies in musical instrument engagement have rarely examined the potential for adolescence and adulthood exposures to independently improve cognition, nor have they been linked with the rate of memory decline over time in older adults. We investigated whether adolescent musical instrument engagement and continued musical instrument engagement over the adult life course were separately associated with higher episodic memory, as well as rate of decline in a large longitudinal cohort.

Methods

Data were from a prospective cohort of high school graduates from 1957. High school music engagement (HSME) was ascertained through graduate yearbooks and assessed as membership in musical performance groups. A questionnaire was used to assess musical engagement through adulthood (MEA) at ages 35, 55, and 65. The episodic memory score was composed of immediate and delayed recall task scores, and was assessed when participants were aged approximately 65 and 72 years old among 5,718 individuals. Linear mixed models were used to assess the association between music, and memory performance and decline over time.

Results

Of high school graduates who participated in the study, 38.1% played music in high school, and 21.1% played music in adulthood. While musical engagement was more common in those who played in childhood, 40% of those who played continuously as an adult did not play in high school. High HSME (B = 0.348, p = 0.049) and continuous MEA (B = 0.424, p = 0.012) were associated with higher memory scores at age 65 after covariate adjustment. When examining memory decline, the benefits of high HSME decreased over time (B = -0.435, p = 0.048), while the rate of decline did not differ between MEA groups. Exploratory models revealed differential benefits for HSME and immediate recall, and MEA and delayed recall.

Conclusion

This study provides further evidence that musical engagement in childhood or adulthood is associated with non-musical cognitive reserve. These two exposures may act differentially in different domains of episodic memory. Further work is needed to determine the relationship between musicianship and the rate of cognitive decline.

Childhood Socioeconomic Status Does Not Predict Late-Life Cognitive Decline in the 1936 Lothian Birth Cohort

This study examined childhood socioeconomic status (SES) as a predictor of later life cognitive decline. Data came from 519 participants in the Lothian Birth Cohort 1936 (LBC1936) study. SES measures at 11 years of age included parental educational attainment, father's occupational status, household characteristics and a composite measure of global childhood SES (i.e., a total of low SES childhood indicators). Cognitive abilities were assessed by the Mini-Mental State Exam at ages 69.8, 72.8 and 76.7 years. Most indicators of low childhood SES (i.e., father manual worker, less than secondary school father education, household overcrowding, exterior located toilet, and global childhood SES) did not predict cognitive decline between the ages of 69.8 and 76.7. Participants with less educated mothers showed an increase in cognitive decline (β = -0.132, p = 0.048, and CI = -0.80, -0.00). The relationship between maternal educational attainment and cognitive decline became non-significant when controlling for adult SES (i.e., participant educational attainment and occupation). Adult SES did not mediate the latter relationship. This study provides new evidence that childhood SES alone is not strongly associated with cognitive decline. New knowledge is critical to improving population health by identifying life span stages in which interventions might be effective in preventing cognitive decline.

Multigenerational Households During Childhood and Trajectories of Cognitive Functioning Among U.S. Older Adults

Objectives

Family structure in childhood influences early brain development and cognitive performance in adulthood. Much less is known about its long-term impact on later-life cognitive functioning. We extend the two-generation family structure approach to investigate the potential contribution of living with grandparents in multigenerational households to differences in cognitive functioning at older ages.

Methods

Data were drawn from 9 waves of the Health and Retirement Study (1998–2014) merged with newly collected childhood family history data. Five types of family structure were assessed: two-parent households, two-parent households with grandparents, single-parent households, single-parent households with grandparents, and grandparent-headed households. Growth curve models were used to estimate trajectories of cognitive functioning over time.

Results

Childhood family structure was significantly associated with level of cognitive functioning, but not to rate of cognitive decline. Relative to those from two-parent households, individuals who grew up in multigenerational households showed higher levels of cognitive functioning, including those living with a single parent and grandparents. Those who lived with a single parent alone were the most disadvantaged. The effects of these multigenerational households persisted net of childhood and adulthood socioeconomic status and health outcomes.

Discussion

Grandparent coresidence may cultivate a socially enriched home environment, providing resources and protection for early cognitive development that could persist throughout life. Multigenerational living arrangements are likely to increase as the contemporary population ages. More research needs to be done to understand the impact of these living arrangements on future generations’ brain health and cognitive aging.

Adverse childhood events and cognitive function among young adults: Prospective results from the national longitudinal study of adolescent to adult health

BACKGROUND

Adverse childhood experiences (ACEs) may have lasting impacts on cognition.

OBJECTIVE

To determine if ACE exposure is prospectively associated with cognition in young adults. We hypothesized that deprivation- and threat-type ACEs as well as higher cumulative ACE exposure predict poorer cognition.

PARTICIPANTS & SETTING

Participants were from the National Longitudinal Study of Adolescent to Adult Health (Add Health), a prospective cohort investigation of U.S. adolescents followed to adulthood. Current study participants were 18-24 years old (Wave III), 24-32 years old (Wave IV), and 31-42 years old (Wave V). The maximum Wave IV sample was 12,288 adults; Wave V was 1277 adults.

METHODS

History of ACEs were assessed at Wave III. Three cognitive indicators were assessed at Wave IV and Wave V using the Rey Auditory Verbal Learning Test (immediate and delayed verbal memory) and the Digit-Span Backward Task (working memory).

RESULTS

The deprivation ACE of not-having-basic-needs met was associated with poorer working (β = 0.14, CI95 -0.26, -0.01), immediate (β=-0.29, CI95 -0.43, -0.15), and delayed memory (β=-0.27, CI95 -0.43, -0.12) at Wave IV; poorer immediate (β=-0.47, CI95-0.79, -0.16) and delayed memory (β=-0.33, CI95 -0.65, -0.01) at Wave V. The threat ACE of sexual abuse was associated with poorer immediate (β=-0.40, CI95 -0.62, -0.17) and delayed memory (β=-0.29, CI95 -0.55, -0.03) at Wave IV. Higher cumulative ACEs predicted poorer delayed memory (β =-0.05, CI95 -0.10, -0.01) at Wave V.

CONCLUSIONS

Higher ACEs, especially deprivation-type, were prospectively linked to poorer cognition. Early wide-scale screening/tailored treatments addressing ACEs and cognitive function may be warranted.

Height and quality of life among older adults (50+) in India: a cross-sectional study

Adult height is a summary measure of health and net nutrition in early childhood. This study examines the association between height and quality-of-life outcomes in older adults (50+) in India. Cross-sectional data from Wave 1 of the World Health Organization (WHO) Study on global AGEing and adult health (SAGE) conducted in 2007 were analysed. The association between height and quality of life was assessed using bivariate and multivariate logistic and linear regression models. The mean WHO quality-of-life score (WHO-QoL) increased from 45.2 among the older adults in the lowest height quintile to 53.2 for those in the highest height quintile. However, the prevalence of self-rated poor quality of life declined from 16.4% in the lowest height quintile to 6.1% in the highest height quintile. In the fully adjusted regression model, height was found to be positively associated with quality-of-life outcomes among both men and women, independent of socioeconomic and physical health confounders. The association was particularly strong for women. Women in the highest height quintile had a 2.65 point higher WHO-QoL score than those in the lowest height quintile. Similarly, the likelihood of reporting a poor quality of life was lower among women in the highest height quintile. Furthermore, measures of economic status, handgrip strength, cognitive ability and poor self-rated health were significantly associated with WHO-QoL and self-rated poor quality of life. Overall, this study revealed a significant association between height and quality of life among older adults in India, suggesting a significant role of childhood circumstances in quality of life in later life.

Is College Completion Associated with Better Cognition in Later Life for People Who Are the Least, or Most, Likely to Obtain a Bachelor's Degree?

OBJECTIVES

Drawing on insights from theorizing on cumulative dis/advantage (CDA), we aimed to advance understanding of educational attainment as a protective factor for later-life cognition by examining whether associations between obtaining a bachelor's degree and later-life cognition differ according to individuals' likelihood of completing college based on characteristics in adolescence.

METHODS

We conducted a propensity score analysis with data from the Wisconsin Longitudinal Study (WLS). Measures to predict college completion were assessed prospectively in adolescence, and a global measure of later-life cognition was based on cognitive assessments at age 65.

RESULTS

College completion by age 25 (vs high school only) was associated with better later-life cognition for both men and women. Among men specifically, associations were stronger for those who were less likely as adolescents to complete college.

DISCUSSION

Results indicate the utility of a CDA perspective for investigating the implications of interconnected early life risk and protective factors for later-life cognition, as well as ways in which college education can both contribute to, as well as mitigate, processes of CDA.

Does the association between cognition and education differ between older adults with gradual or rapid trajectories of cognitive decline?

Education is associated with improved baseline cognitive performance in older adults, but the association with maintenance of cognitive function is less clear. Education may be associated with different types of active cognitive reserve in those following different cognitive trajectories. We used data on n = 5642 adults aged >60 from the English Longitudinal Study of Aging (ELSA) over 5 waves (8 years). We used growth mixture models to test if the association between educational attainment and rate of change in verbal fluency or immediate recall varied by latent class trajectory. For recall, 91.5% (n = 5164) of participants were in a gradual decline class and 8.5% (n = 478) in a rapid decline class. For fluency, 90.0% (n = 4907) were in a gradual decline class and 10.0% (n = 561) were in a rapid decline class. Educational attainment was associated with improved baseline performance for both verbal fluency and recall. In the rapidly declining classes, educational attainment was not associated with rate of change for either outcome. In the verbal fluency gradual decline class, education was associated with higher (an additional 0.05-0.38 words per 2 years) or degree level education (an additional 0.04-0.42 words per 2 years) when compared to those with no formal qualifications. We identified no evidence of a protective effect of education against rapid cognitive decline. There was some evidence of active cognitive reserve for verbal fluency but not recall, which may reflect a small degree of domain-specific protection against age-related cognitive decline.

Education and Cognition in Middle Age and Later Life: The Mediating Role of Physical and Cognitive Activity

OBJECTIVES

Although educational attainment is related to cognitive function in later life, little is known about the mechanisms involved. This study assessed the independent mediating effects of two behavioral variables, physical and cognitive activity, on the association between educational attainment and cognitive function and change.

METHODS

Data were derived from the three waves of the Midlife in the United States (MIDUS) study. Predictors (educational attainment) were from the 1995 baseline, mediators (physical and cognitive activities) were from the 2004 wave, and outcomes (cognitive function) were from the 2004 and 2013 waves. Conditional process modeling was applied using PROCESS in SPSS.

RESULTS

There were both direct and indirect effects of educational attainment on level and change of executive function (EF) and episodic memory (EM). Physical activity and cognitive activity were both significant mediators for cognitive level. For mediators of change, however, cognitive activity was significant for EF and physical activity was significant for EM.

DISCUSSION

Physical and cognitive activity are discussed as possible factors for protecting against cognitive decline in later life. The findings have implications for advancing supportive policies and practices related to maximizing the benefits of education and physical and cognitive activities for cognition in middle age and later life.

Offspring Educational Attainment and Older Parents' Cognition in Mexico

Population-level disparities in later-life cognitive health point to the importance of family resources. Although the bulk of prior work establishes the directional flow of resources from parents to offspring, the "linked lives" perspective raises the question of how offspring resources could affect parental health as well. This paper examines whether adult children's education influences older parents' (aged 50+) cognitive health in Mexico, where schooling reforms have contributed to significant gains in the educational achievements of recent birth cohorts. Harnessing a change in compulsory school laws and applying an instrumental variables approach, we found that each year of offspring schooling was associated with higher overall cognition among parents, but was less predictive across different cognitive functioning domains. More offspring schooling improved parents' cognitive abilities in verbal learning, verbal fluency, and orientation, but not in visual scanning, visuo-spatial ability, or visual memory. The beneficial effects of offspring schooling on those cognitive domains are more salient for mothers compared to fathers, suggesting potential gendered effects in the influence of offspring schooling. The results remained robust to controls for parent-child contact and geographic proximity, suggesting other avenues through which offspring education could affect parental health and a pathway for future research. Our findings contribute to growing research which stresses the causal influence of familial educational attainment on population health.

UDSNB 3.0 Neuropsychological Test Norms in Older Adults from a Diverse Community: Results from the Einstein Aging Study (EAS)

BACKGROUND

The Uniform Data Set, Version 3 Neuropsychological Battery (UDSNB3.0), from the database of the University of Washington's National Alzheimer's Coordinating Center (NACC), is widely used to characterize cognitive performance in clinical and research settings; however, norms for underrepresented community-based samples are scarce.

OBJECTIVE

We compared UDSNB 3.0 test scores between the Einstein Aging Study (EAS), composed of racially/ethnically diverse, community-dwelling older adults aged≥70 and the NACC, and report normative data from the EAS.

METHODS

Analyses included 225 cognitively normal EAS participants and comparable data from 5,031 NACC database participants. Linear regression models compared performance between the samples, adjusting for demographics (sex, age, education, race/ethnicity), depressive symptoms, and whether English was the first language. Linear regression models to examine demographic factors including age, sex, education and race/ethnicity as predictors for the neuropsychological tests were applied in EAS and NACC separately and were used to create a demographically adjusted z-score calculator.

RESULTS

Cognitive performance across all domains was worse in the EAS than in the NACC, adjusting for age, sex, education, race/ethnicity, and depression, and the differences remained in visuo-construction, visuospatial memory, confrontation naming, visual attention/processing speed, and executive functioning after further adjusting for whether English was the first language. In both samples, non-Hispanic Whites outperformed non-Hispanic Blacks and more education was associated with better cognitive performance.

CONCLUSION

Differences observed in demographic, clinical, and cognitive characteristics between the community-based EAS sample and the nationwide NACC sample suggest that separate normative data that more accurately reflect non-clinic, community-based populations should be established.