Life course financial mobility and later-life memory function and decline by gender, and race and ethnicity: an intersectional analysis of the US KHANDLE and STAR cohort studies.

BACKGROUND: Intersectionality has rarely been considered in research studies of cognitive ageing. We investigated whether life-course financial mobility is differentially associated with later-life memory function and decline across intersectional identities defined by gender, and race and ethnicity. METHODS: Data were from two harmonised multiethnic cohorts (the Kaiser Healthy Aging and Diverse Life Experiences cohort and the Study of Healthy Aging in African Americans cohort) in northern California, USA (n=2340). Life-course financial mobility, measured using a combination of self-reported financial capital measures in childhood (from birth to age 16 years) and later adulthood (at the cohort baseline) was defined as consistently high, upwardly mobile, downwardly mobile, or consistently low. We clustered individuals into 32 strata representing intersectional identities defined by life-course financial mobility combined with gender, and race and ethnicity. Verbal episodic memory was assessed using the Spanish and English Neuropsychological Assessment Scales over four waves from 2017 to 2023. Adjusted mixed-effects linear regression models were estimated with and without fixed effects of gender, race and ethnicity, and financial mobility, to evaluate whether the random effects of the intersectional identity strata contributed variance to memory beyond individual fixed effects. FINDINGS: Mean age was 73·6 years (SD 8·1). Of 2340 individuals, 1460 (62·4%) were women, 880 (37·6%) were men, 388 (16·6%) were Asian, 1136 (48·5%) were Black, 334 (14·3%) were Latinx, and 482 (20·6%) were White. Consistently low and downwardly mobile financial capital were strongly negatively associated with later-life memory at baseline (-0·162 SD units [95% CI -0·273 to -0·051] for consistently low and -0·171 [-0·250 to -0·092] for downwardly mobile), but not rate of change over time. Intersectional identities contributed 0·2% of memory variance after accounting for the fixed effects of gender, race and ethnicity, and financial mobility. INTERPRETATION: Consistently low and downward life-course financial mobility are associated with lower later-life memory function. Intersectional identities defined by financial mobility in addition to gender, and race and ethnicity, contribute negligible additional variance to later-life memory in this study setting. FUNDING: US National Institute on Aging, US National Institutes of Health.

Effect of a cash transfer intervention on memory decline and dementia probability in older adults in rural South Africa.

Evidence on cash transfers as a population-level intervention to support healthy cognitive aging in low-income settings is sparse. We assessed the effect of a cash transfer intervention on cognitive aging outcomes in older South African adults. We leveraged the overlap in the sampling frames of a Phase 3 randomized cash transfer trial [HIV Prevention Trial Network (HPTN) 068, 2011-2015] and an aging cohort [Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community (HAALSI), 2014-2022] in rural Mpumalanga Province, South Africa. In 2011/12, young women and their primary caregivers were randomly assigned 1:1 to receive a monthly cash transfer or control. In 2014/2015, 862 adults aged 40+ y living in trial households were enrolled in the HAALSI cohort, with cognitive data collected in three waves over 7 y. We estimated the impact of the intervention on rate of memory decline and dementia probability scores. Memory decline in the cash transfer arm was 0.03 SD units (95% CI: 0.002, 0.05) slower per year than in the control arm. Dementia probability scores were three percentage points lower in the cash transfer arm than the control arm (ß = -0.03; 95% CI: -0.05, -0.001). Effects were consistent across subgroups. A modestly sized household cash transfer delivered over a short period in mid- to later-life led to a meaningful slowing of memory decline and reduction in dementia probability 7 y later. Cash transfer programs could help stem the tide of new dementia cases in economically vulnerable populations in the coming decades.

Impact of the South African Child Support Grant on memory decline and dementia probability in rural and low-income mothers, 2014-2021.

INTRODUCTION: Aging populations across sub-Saharan Africa are rapidly expanding, leading to an increase in the burden of Alzheimer's disease and related dementias (ADRD). Cash transfer interventions are one plausible mechanism to combat ADRD at a population-level in low-income settings. We exploited exogenous variation in eligibility for South Africa's Child Support Grant (CSG) to estimate the longitudinal association between potential CSG benefit and cognitive trajectories in rural mothers with <10 children (n = 1090). METHODS: South Africa's CSG delivers monthly cash payments to primary caregivers, predominantly mothers, to offset the costs associated with child rearing. This study implemented a quasi-experimental design using data (2014-2022) from a rural, low-income cohort in the Agincourt research area, South Africa. We fit linear mixed effects models and generalized linear models to estimate the association of potential CSG benefit per eligible child with memory decline and dementia probability, respectively. We stratified all models by the mother's total number of children (1-4 and 5-9) and examined effect modification by household wealth and the mother's education level. RESULTS: Having above median CSG per eligible child was associated with higher baseline memory scores (ß = 0.12 SD units, 95% CI = 0.02, 0.22) but steeper memory decline (ß = -0.02 SD units, 95% CI = -0.04, -0.00) compared to below median CSG. Within stratified analyses, this effect was primarily observed among mothers with 5-9 children. No associations were observed between potential CSG per eligible child and dementia probability. CONCLUSIONS: Our findings support the use of large-scale cash transfers as a promising intervention to promote healthy cognitive aging in mid-life women within rural, low-income settings. However, we found evidence that the CSG in its current structure may not be sufficient support for women to sustain measurable cognitive benefits over the long-term.

DNA Methylation Age Acceleration Mediates the Relationship between Systemic Inflammation and Cognitive Impairment.

Background: Chronic inflammation and DNA methylation are potential mechanisms in dementia etiology. The linkage between inflammation and DNA methylation age acceleration in shaping dementia risk is understudied. We explored the association of inflammatory cytokines with cognitive impairment and whether DNA methylation age acceleration mediates this relationship. Methods: In a subset of the 2016 wave of the Health and Retirement Study (n=3,346, age>50), we employed logistic regression to estimate the associations between each inflammatory cytokine (interleukin-6 (IL-6), C-reactive protein (CRP), and insulin-like growth factor-1 (IGF-1)), and both Langa-Weir classified cognitive impairment non-dementia and dementia, respectively. We calculated DNA methylation age acceleration residuals by regressing GrimAge on chronologic age. We tested if DNA methylation age acceleration mediated the relationship between systemic inflammation and cognitive impairment, adjusting for sociodemographic, behavioral factors, chronic conditions, and cell type proportions. Results: The prevalence of cognitive impairment was 16%. In the fully-adjusted model, participants with a doubling of IL-6 levels had 1.12 (95% CI: 1.02-1.22) times higher odds of cognitive impairment. Similar associations were found for CRP and IGF-1. Participants with a doubling of IL-6 levels had 0.77 (95% CI: 0.64, 0.90) years of GrimAge acceleration. In mediation analyses with each cytokine as predictor separately, 17.7% (95% CI: 7.0%, 50.9%) of the effect of IL-6 on cognitive impairment was mediated through DNA methylation age acceleration. Comparable mediated estimates were found for CRP and IGF-1. Conclusions: Systemic inflammation is associated with cognitive impairment, with suggestive evidence that this relationship is partially mediated through DNA methylation age acceleration.

The mediating role of systemic inflammation and moderating role of racialization in disparities in incident dementia.

BACKGROUND: Exposure to systemic racism is linked to increased dementia burden. To assess systemic inflammation as a potential pathway linking exposure to racism and dementia disparities, we investigated the mediating role of C-reactive protein (CRP), a systemic inflammation marker, and the moderating role of the racialization process in incident dementia. METHODS: In the US Health and Retirement Study (n = 6,908), serum CRP was measured at baseline (2006, 2008 waves). Incident dementia was classified by cognitive tests over a six-year follow-up. Self-reported racialized categories were a proxy for exposure to the racialization process. We decomposed racialized disparities in dementia incidence (non-Hispanic Black and/or Hispanic vs. non-Hispanic white) into 1) the mediated effect of CRP, 2) the moderated portion attributable to the interaction between racialized group membership and CRP, and 3) the controlled direct effect (other pathways through which racism operates). RESULTS: The 6-year cumulative incidence of dementia is 12%. Among minoritized participants (i.e., non-Hispanic Black and/or Hispanic), high CRP levels ( ≥ 75th percentile or 4.73µg/mL) are associated with 1.26 (95%CI: 0.98, 1.62) times greater risk of incident dementia than low CRP ( < 4.73µg/mL). Decomposition analysis comparing minoritized versus non-Hispanic white participants shows that the mediating effect of CRP accounts for 3% (95% CI: 0%, 6%) of the racial disparity, while the interaction effect between minoritized group status and high CRP accounts for 14% (95% CI: 1%, 27%) of the disparity. Findings are robust to potential violations of causal mediation assumptions. CONCLUSIONS: Minoritized group membership modifies the relationship between systemic inflammation and incident dementia.

Higher levels of inflammation in blood are linked to greater dementia risk in older adults. Non-Hispanic Black and Hispanic Americans have higher inflammation levels compared to non-Hispanic white Americans. We conducted a study to examine whether high levels of inflammation could explain differences in dementia risk among these racial groups. We found that differences in inflammation levels in non-Hispanic Black or Hispanic adults modestly explain their higher risk of dementia compared to non-Hispanic white adults. These findings suggest that interventions aimed at reducing high levels of inflammation in minoritized US adults could ameliorate racial differences in dementia risk.

Could differential under-reporting of loneliness between men and women bias the gender-specific association between loneliness duration and rate of memory decline? A probabilistic bias analysis of effect modification.

Gender is an observed effect modifier of the association between loneliness and memory aging. However, this effect modification may be a result of information bias due to differential loneliness under-reporting by gender. We applied probabilistic bias analyses to examine whether effect modification of the loneliness-memory decline relationship by gender is retained under three simulation scenarios with various magnitudes of differential loneliness under-reporting between men and women. Data were from biennial interviews with adults aged 50+ in the US Health and Retirement Study from 1996-2016 (5,646 women and 3,386 men). Loneliness status (yes vs. no) was measured from 1996-2004 using the CES-D loneliness item and memory was measured from 2004-2016. Simulated sensitivity and specificity of the loneliness measure were informed by a validation study using the UCLA Loneliness Scale as a gold standard. The likelihood of observing effect modification by gender was higher than 90% in all simulations, although the likelihood reduced with an increasing difference in magnitude of the loneliness under-reporting between men and women. The gender difference in loneliness under-reporting did not meaningfully affect the observed effect modification by gender in our simulations. Our simulation approach may be promising to quantify potential information bias in effect modification analyses.

Altered place engagement since COVID-19: A multi-method study of community participation and health among older americans.

Little is known about longer-term changes to community participation since the COVID-19 pandemic onset and potential implications for health and wellbeing in later life. This multi-method investigation analyzes national data from the COVID-19 Coping Study. Statistical analyses of survey data (n = 1,630; mean age 67.9 years; data collected April/May 2022) identified that adults residing in the US still tended to stay inside their homes more often since the pandemic onset. Overall, participants decreased their engagement with amenities such as eateries, gyms, and arts and cultural sites. Reflexive thematic analysis of semi-structured in-depth interviews (n = 57; mean age 70.7 years; data collected May-July 2021) identified altered community participation with perceived long-term impacts on physical, mental, and social health and wellbeing. The results provide novel insights about the critical nature of 'third places' to support later life, and policy implications to strengthen community environments. Investment in outdoor, well-ventilated, and distanced third places may support wellbeing.

Mid-Life Household Food Insecurity and Subsequent Memory Function and Rate of Decline in Rural South Africa, 2004-2022.

INTRODUCTION: We aimed to investigate mid-life food insecurity over time in relation to subsequent memory function and rate of decline in Agincourt, rural South Africa. METHODS: Data from the longitudinal Agincourt Health and Socio-Demographic Surveillance System (Agincourt HDSS) were linked to the population-representative Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI). Food insecurity (yes vs. no) and food insecurity intensity (never/rarely/sometimes vs. often/very often) in the past month were assessed every 3 years from 2004 to 2013 in Agincourt HDSS. Cumulative exposure to each food insecurity measure was operationalized as 0, 1, and ≥2 time points. Episodic memory was assessed from 2014/15 to 2021/22 in HAALSI. Mixed-effects linear regression models were fitted to investigate the associations of each food insecurity measure with memory function and rate of decline over time. RESULTS: A total of 3,186 participants (mean age [SD] in 2004: 53 [12.87]; range: 30-96) were included and 1,173 (36%) participants experienced food insecurity in 2004, while this figure decreased to 490 (15%) in 2007, 489 (15%) in 2010, and 150 (5%) in 2013. Experiencing food insecurity at one time point (vs. never) from 2004 to 2013 was associated with lower baseline memory function (ß = -0.095; 95% CI: -0.159 to -0.032) in 2014/15 but not rate of memory decline. Higher intensity of food insecurity at ≥2 time points (vs. never) was associated with lower baseline memory function (ß = -0.154, 95% CI: -0.338 to 0.028), although the estimate was imprecise. Other frequencies of food insecurity and food insecurity intensity were not associated with memory function or decline in the fully adjusted models. CONCLUSION: In this setting, mid-life food insecurity may be a risk factor for lower later-life memory function, but not decline.

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

PURPOSE: Cardiovascular risk factors (CVRFs) are associated with increased risk for cognitive impairment and decline in the general population, but less is known about how CVRFs might influence cognitive aging among older cancer survivors. We aimed to determine how CVRFs prior to a cancer diagnosis affect post-cancer diagnosis memory aging, compared to cancer-free adults, and by race/ethnicity. METHODS: Incident cancer diagnoses and memory (immediate and delayed recall) were assessed biennially in the US Health and Retirement Study (N = 5,736, 1998-2018). CVRFs measured at the wave prior to a cancer diagnosis included self-reported cigarette smoking, obesity, diabetes, heart disease, hypertension, and stroke. Multivariable-adjusted linear mixed-effects models evaluated the rate of change in standardized memory score (SD/decade) post-cancer diagnosis for those with no, medium, and high CVRFs, compared to matched cancer-free adults, overall and stratified by sex and race/ethnicity. RESULTS: Higher number of CVRFs was associated with worse baseline memory for both men and women, regardless of cancer status. Cancer survivors with medium CVRFs had slightly slower rates of memory decline over time relative to cancer-free participants (0.04 SD units/decade [95% CI: 0.001, 0.08]). Non-Hispanic Black (NHB) and Hispanic cancer-free participants and cancer survivors had worse baseline memory than their Non-Hispanic White (NHW) counterparts. CONCLUSIONS: CVRFs were associated with worse baseline memory function, but not decline, for cancer-free adults and cancer survivors. Racial disparities were largely similar between cancer survivors and cancer-free adults. IMPLICATIONS FOR CANCER SURVIVORS: These findings may inform hypotheses about pre-diagnosis multimorbidity and cognitive aging of cancer survivors from diverse groups.

The Impact of Old Age Pension Eligibility on Alcohol Consumption: Evidence From a Population-Based Study in Rural South Africa.

Background and Objectives: Alcohol causes more than 3 million deaths a year globally and contributes to over 5% of global disease and injury. Heavy drinking and alcohol use disorders among older adults have increased in the last 10-15 years. For individuals living in low-income countries, where wages are low and unemployment is high, old age pensions may provide a significant increase in household income. In turn, the receipt of supplementary income may increase spending on alcohol. Earlier life factors and socioeconomic status may affect alcohol consumption, making it difficult to directly assess the impact of income on alcohol consumption. This study reduces the potential for endogeneity with other life factors by exploiting an exogenous increase in income from old age pensions to isolate the impact of extra income on alcohol consumption for older adults. Research Design and Methods: We used a regression discontinuity design to assess changes in drinking patterns among rural, low-income adults who were 3 years below and 3 years above South Africa's Old Age Pension Grant eligibility threshold (age 60). We assessed this relationship separately by gender and for employed and unemployed individuals. Results: We observed a significantly increased alcohol use associated with the Old Age Pension Grant eligibility for employed men (ß = 4.57, 95% confidence interval: 1.72-12.14). We did not observe this same trend for unemployed men or for women. Discussion and Implications: The analysis in this study indicates that increased income from reaching the pension eligibility age may contribute to an increase in alcohol consumption for employed men. Interventions, such as informational campaigns on the risks of alcohol consumption for older adults or age-appropriate health interventions to help individuals reduce alcohol consumption, targeted around the time of pension eligibility age for employed men may help to reduce alcohol-related harms in low-income, rural sub-Saharan African settings.

The Impact of the Older Person's Grant Expansion on Hypertension Among Older Men in Rural South Africa: Findings From the HAALSI Cohort.

Background and Objectives: Hypertension is a major modifiable contributor to disease burden in sub-Saharan Africa. We exploited an expansion to age eligibility for men in South Africa's noncontributory public pension to assess the impact of pension eligibility on hypertension in a rural, low-income South African setting. Research Design and Methods: Data were from 1 247 men aged ≥60 in the population-representative Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa in 2014/2015. We identified cohorts of men from 0 (controls, aged ≥65 at pension expansion) through 5 years of additional pension eligibility based on their birth year. Using the modified Framingham Heart Study hypertension risk prediction model, and the Wand et al. model modified for the South African population, we estimated the difference in the probabilities of hypertension for men who benefitted from the pension expansion relative to the control. We conducted a negative control analysis among older women, who were not eligible for pension expansion, to assess the robustness of our findings. Results: Older men with 5 additional years of pension eligibility had a 6.9-8.1 percentage point greater probability of hypertension than expected without the pension expansion eligibility. After accounting for birth cohort effects through a negative control analysis involving older women reduced estimates to a 3.0-5.2 percentage point greater probability of hypertension than expected. We observed a mean 0.2 percentage point increase in the probability of hypertension per additional year of pension eligibility, but this trend was not statistically significant. Discussion and Implications: Although the Older Person's Grant is important for improving the financial circumstances of older adults and their families in South Africa, expanded pension eligibility may have a small, negative short-term effect on hypertension among older men in this rural, South African setting.

Does Neighborhood Socioeconomic Status Alter Memory Change Associated with a Cancer Diagnosis? Preliminary Evidence from the US Health and Retirement Study.

BACKGROUND: Neighborhood disadvantage has been linked to cognitive impairment, but little is known about the effect of neighborhood disadvantage on long-term cancer-related memory decline. METHODS: Incident cancer diagnosis and memory (immediate and delayed recall, combined with proxy-reported memory) were assessed at biennial interviews in the US Health and Retirement Study (N = 13,293, 1998-2016). Neighborhood disadvantage was measured using the National Neighborhood Data Archive disadvantage index, categorized into tertiles (T1: least disadvantaged-T3: most disadvantaged). Linear mixed-effects models estimated the standardized memory trajectories in participants with or without cancer, by neighborhood disadvantage. RESULTS: Living in more disadvantaged neighborhoods was associated with worse mean memory function and steeper memory declines, regardless of cancer status. An incident cancer diagnosis was associated with an acute memory drop for those living in least disadvantaged neighborhoods but not more disadvantaged neighborhoods [T1: -0.05, 95% confidence interval (CI): -0.08, -0.01; T3: -0.13, 95% CI: -0.06, 0.03]. Cancer survivors in the least disadvantaged neighborhoods had a slight memory advantage in the years prior to diagnosis (T1: 0.09, 95% CI: 0.04, 0.13) and after diagnosis (T1: 0.07, 95% CI: 0.01, 0.13). CONCLUSIONS: An incident cancer diagnosis among those living in the least disadvantaged neighborhoods was associated with an acute memory drop at the time of diagnosis and a long-term memory advantage before and after diagnosis compared with cancer-free individuals in similar neighborhoods. IMPACT: These findings could inform interventions to promote cancer survivor's long-term aging. Future studies should investigate the social and biological pathways through which neighborhood socioeconomic status could influence cancer-related memory changes.

Child support grant expansion and cognitive function among women in rural South Africa: Findings from a natural experiment in the HAALSI cohort.

BACKGROUND: Cash transfers are a promising but understudied intervention that may protect cognitive function in adults. Although South Africa has a rapidly ageing population, little is known about the nature of association between cash transfers and cognitive function in this setting. OBJECTIVES: We leveraged age-eligibility expansions to South Africa's Child Support Grant (CSG) to investigate the association between duration of CSG eligibility and cognitive function of biological mothers of child beneficiaries in South Africa. METHODS: We analysed 2014/2015 baseline data from 944 women, aged 40-59 years with at least one CSG-eligible child, enrolled in the population-representative HAALSI cohort in Agincourt, South Africa. Duration of CSG eligibility for each mother was calculated based on the birth dates of all their children and the CSG age-eligibility expansion years (2003-2012). Cognitive function was measured using a cognitive battery administered at the HAALSI baseline interview. Linear regression was used to estimate the association between duration of CSG eligibility, dichotomized as low (≤10 years) and high (>10 years) eligibility, and cognitive function z-scores of the mothers. RESULTS: High vs. low duration of CSG eligibility, was associated with higher cognitive function z-scores in the full sample [ß: 0.15 SD units; 95% CI: 0.04, 0.26; p-value = 0.01]. In mothers with one to four lifetime children, but not five or more, high vs. low duration of CSG eligibility, was associated with higher cognitive function z-scores [ß: 0.19 SD units; 95% CI: 0.05, 0.34, p-value = 0.02]. CONCLUSION: Government cash transfers given to support raising children may confer substantial protective effects on the subsequent cognitive function of mothers. Further studies are needed to understand how parity may influence this relationship. Our findings bring evidence to policymakers for designing income supplementation programmes to promote healthy cognitive ageing in low-income settings.

Mid-life employment trajectories and subsequent memory function and rate of decline in rural South Africa, 2000-22.

AIM: To investigate mid-life employment trajectories in relation to later-life memory function and rate of decline in rural South Africa. METHODS: Data from the Agincourt Health and Socio-Demographic Surveillance System were linked to the 'Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa' (HAALSI) in rural Agincourt, South Africa (N = 3133). Employment was assessed every 4 years over 2000-12 as being employed (0, 1, 2 and ≥3 time points), being employed in a higher-skill occupation (0, 1, 2 and ≥3 time points) and dynamic employment trajectories identified using sequence analysis. Latent memory z-scores were assessed over 2014-22. Mixed-effects linear regression models were fitted to examine the associations of interest. RESULTS: Sustained mid-life employment from 2000-12 (ß = 0.052, 95% CI: -0.028 to 0.132, 1 vs 0 time points; ß = 0.163, 95% CI: 0.077 to 0.250, 2 vs 0 time points; ß = 0.212, 95% CI: 0.128 to 0.296, ≥3 vs 0 time points) and greater time spent in a higher-skill occupation (ß = 0.077, 95% CI: -0.020 to 0.175, 1 vs 0 time points; ß = 0.241, 95% CI: 0.070 to 0.412, 2 vs 0 time points; ß = 0.361, 95% CI: 0.201 to 0.520, ≥3 vs 0 time points) were associated with higher memory scores in 2014/15, but not subsequent rate of memory decline. Moving from a lower-skill to higher-skill occupation was associated with higher memory function, but a faster rate of decline over 2014-22. CONCLUSIONS: Sustained mid-life employment, particularly in higher-skill occupations, may contribute to later-life memory function in this post-Apartheid South African setting.

Cross-national comparisons of later-life cognitive function using data from the Harmonized Cognitive Assessment Protocol (HCAP): Considerations and recommended best practices.

The Harmonized Cognitive Assessment Protocol (HCAP) is a major innovation that provides, for the first time, harmonized data for cross-national comparisons of later-life cognitive functions that are sensitive to linguistic, cultural, and educational differences across countries. However, cognitive function does not lend itself to direct comparison across diverse populations without careful consideration of the best practices for such comparisons. This perspective discusses theoretical and methodological considerations and offers a set of recommended best practices for conducting cross-national comparisons of risk factor associations using HCAP data. Because existing and planned HCAP studies provide cognition data representing an estimated 75% of the global population ≥65 years of age, these recommended best practices will support high-quality comparative analyses of cognitive aging around the world. The principles described in this perspective are applicable to any researcher aiming to integrate or compare harmonized data on cognitive outcomes and their risk and protective factors across diverse populations.

Location Matters: The Role of the Neighborhood Environment for Incident Cardiometabolic Disease in Adults Aging With Physical Disability.

PURPOSE: People aging with disability may be limited in their ability to engage in healthy behaviors to maintain cardiometabolic health. We investigated the role of health promoting features in the neighborhood environment for incident cardiometabolic disease in adults aging with physical disability in the United States. DESIGN: Retrospective cohort study. SETTING: Optum's Clinformatics® Data Mart Database (2007-2018) of administrative health claims. SUBJECTS: ICD-9-CM codes were used to identify 15 467 individuals with a diagnosis of Cerebral Palsy, Spina Bifida, Multiple Sclerosis, or Spinal Cord Injury. MEASURES: Cardiometabolic disease was identified using ICD-9-CM/ICD-10-CM codes over 3 years of follow-up. Measures of the neighborhood environment came from the National Neighborhood Data Archive and linked to individual residential ZIP codes over time. Covariates included age, sex, and comorbid health conditions. ANALYSIS: Cox regression models estimated hazard ratios (HR) for incident cardiometabolic disease. Using a 1-year lookback period, individuals with pre-existing cardiometabolic disease were excluded from the analysis. RESULTS: Net of individual risk factors, residing in neighborhoods with a greater density of broadband Internet connections (HR = .88, 95% CI: .81, .97), public transit stops (HR = .89, 95% CI: .83, .95), recreational establishments (HR = .89, 95% CI: .83, .96), and parks (HR = .88, 95% CI: .82, .94), was associated with reduced risk of 3-year incident cardiometabolic disease. CONCLUSION: Findings identify health-promoting resources that may mitigate health disparities in adults aging with disability.

Educational Attainment and Later-Life Cognitive Function in High- and Middle-Income Countries: Evidence From the Harmonized Cognitive Assessment Protocol.

OBJECTIVES: Identifying social policies that can promote cognitive health is crucial for reducing the global burden of dementia. We evaluated the importance of educational attainment for later-life cognitive function in various social and geographic settings. METHODS: Using harmonized data for individuals aged ≥65 years from the United States Health and Retirement Study (HRS) and its international partner studies in England, Mexico, China, and India, and each study's respective Harmonized Cognitive Assessment Protocol (HCAP), we conducted a cross-national comparative study to examine the role of educational attainment in later-life cognitive function across countries (n = 14,980, 2016-2019). We used multivariable-adjusted regression to estimate associations between educational attainment and harmonized global cognitive function scores. RESULTS: In Mexico, China, and India, the general cognitive function scores on average are approximately one standard deviation of the HRS-HCAP cognitive function score distribution lower compared to the United States and England, paralleling patterns of educational attainment across countries. In all countries, higher educational attainment was associated with progressively higher later-life cognitive function scores. Population-level differences in educational attainment explained about 50%-90% of the observed differences in cognitive function scores across countries. DISCUSSION: The relationship between education and later-life cognitive function across social and geographic contexts underscores the crucial role of education to promote cognitive health and reduce dementia risk. Continual improvement of educational attainment in low- and middle-income settings may yield a significant pay-off in later-life cognitive health.

Does education moderate gender disparities in later-life memory function? A cross-national comparison of harmonized cognitive assessment protocols in the United States and India.

INTRODUCTION: We compared gender disparities in later-life memory, overall and by education, in India and the United States (US). METHODS: Data (N = 7443) were from harmonized cognitive assessment protocols (HCAPs) in the Longitudinal Aging Study of India-Diagnostic Assessment of Dementia (LASI-DAD; N = 4096; 2017-19) and US Health and Retirement Study HCAP (HRS-HCAP; N = 3347; 2016-17). We derived harmonized memory factors from each study using confirmatory factor analysis. We used multivariable-adjusted linear regression to compare gender disparities in memory function between countries, overall and by education. RESULTS: In the United States, older women had better memory than older men (0.28 SD-unit difference; 95% CI: 0.22, 0.35). In India, older women had worse memory than older men (-0.15 SD-unit difference; 95% CI: -0.20, -0.10), which attenuated with increasing education and literacy. CONCLUSION: We observed gender disparities in memory in India that were not present in the United States, and which dissipated with education and literacy.

Association of cancer history with structural brain aging markers of Alzheimer's disease and related dementias risk.

INTRODUCTION: Cancer survivors are less likely than comparably aged individuals without a cancer history to develop Alzheimer's disease and related dementias (ADRD). METHODS: In the UK Biobank, we investigated associations between cancer history and five structural magnetic resonance imaging (MRI) markers for ADRD risk, using linear mixed-effects models to assess differences in mean values and quantile regression to examine whether associations varied across the distribution of MRI markers. RESULTS: Cancer history was associated with smaller mean hippocampal volume (b = -19 mm3 , 95% CI = -36, -1) and lower mean cortical thickness in the Alzheimer's disease signature region (b = -0.004 mm, 95% CI = -0.007, -0.000). Quantile regressions indicated individuals most vulnerable to ADRD were more affected by cancer history. DISCUSSION: Some brain MRI markers associated with ADRD risk were elevated in adults with a history of cancer. The magnitude of the adverse associations varied across quantiles of neuroimaging markers, and the pattern suggests possible harmful associations for individuals already at high ADRD risk. HIGHLIGHTS: We found no evidence of an inverse association between cancer history and ADRD-related neurodegeneration. Cancer history was associated with smaller mean hippocampal volume and lower mean cortical thickness in the Alzheimer's disease signature region. Quantile regressions indicated individuals most vulnerable to ADRD were more affected by cancer history.