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Background: As global populations age, cross-national comparisons of cognitive health and dementia risk are increasingly valuable. It remains unclear, however, whether country-level differences in cognitive function are attributable to population differences or bias due to incommensurate measurement. To demonstrate an effective method for cross-national comparison studies, we aimed to statistically harmonize measures of episodic memory and language function across two population-based cohorts of older adults in the United States (HRS HCAP) and India (LASI-DAD)., Methods: Data for 3,496 HRS HCAP (≥65 years) and 3,152 LASI-DAD (≥60 years) participants were statistically harmonized for episodic memory and language performance using confirmatory factor analysis (CFA) methods. Episodic memory and language factor variables were investigated for differential item functioning (DIF) and precision., Results: CFA models estimating episodic memory and language domains based on a priori adjudication of comparable items fit the data well. DIF analyses revealed that four out of ten episodic memory items and five out of twelve language items measured the underlying construct comparably across samples. DIF-modified episodic memory and language factor scores showed comparable patterns of precision across the range of the latent trait for each sample., Conclusions: Harmonization of cognitive measures will facilitate future investigation of cross-national differences in cognitive performance and differential effects of risk factors, policies, and treatments, reducing study-level measurement and administrative influences. As international aging studies become more widely available, advanced statistical methods such as those described in this study will become increasingly central to making universal generalizations and drawing valid conclusions about cognitive aging of the global population., Competing Interests: The authors have declared that no competing interests exist.

Racial/ethnic inequalities in dementia risk are a major public health and health justice concern. Group differences that persist despite adjustment for socioeconomic and vascular indicators suggest that known dementia risk factors exhibit differential impact across race/ethnicity and/or there are unrecognized dementia risk factors that are racially patterned. This article provides targeted examples of both of these possibilities. First, depressive symptoms and white matter hyperintensities represent two known dementia risk factors that more strongly relate to negative cognitive outcomes among Black older adults than Whites, pointing to the need to consider contextual factors. Second, racial discrimination and external perceived control predict worse brain and cognitive aging above and beyond known risk factors. These psychosocial factors warrant explicit consideration in dementia cohort studies. Several challenges appear to be particularly relevant to the study of dementia inequalities, including selective survival and recruitment. These challenges complicate not only cross-study comparisons, but also within-study causal inferences. This article provides recommendations for addressing these challenges in order to accelerate high-quality research on dementia inequalities. Stemming from these recommendations, the article introduces the design and methods of the Michigan Cognitive Aging Project, a new, racially-balanced cohort study of Black and White adults transitioning to late life. In sum, careful research with community partners is needed to more fully explore the factors and contexts that create and sustain racial/ethnic disparities, as well as those that buffer against them. The ultimate goal of this research is to facilitate the dismantling of structural barriers to health justice for diverse older people. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Objective: The lack of disease-modifying pharmacological agents for dementia highlights the critical importance of prevention, but known modifiable factors (e.g., education, physical health and health behaviors, depression, and social isolation) do not fully represent potential intervention targets. Positive psychosocial factors predict cognitive aging outcomes above and beyond known risk factors and may also correspond to upstream determinants that open up new avenues for prevention and intervention, as well as for reducing racial/ethnic inequalities in dementia. In this brief report, I summarize contemporary evidence for three positive psychosocial factors that appear to be particularly relevant to cognitive aging: perceived control, religious involvement, and social relations., Methods: Targeted review and synthesis of published studies., Results: Each of the multidimensional constructs appears to contain "active ingredients" that could help to optimize cognitive aging through disparate mechanisms. Although historically marginalized racial/ethnic groups face disproportionate barriers to accessing certain psychosocial protective factors (e.g., perceived control), these same groups also exhibit naturally occurring sources of psychosocial resilience (e.g., religious involvement) that allow them to achieve better late-life cognitive health than would be otherwise expected. With regard to social relations, converging evidence from disparate studies shows that fostering late-life friendships in particular may have high potential for building cognitive reserve and promoting healthy cognitive aging., Conclusions: Positive psychosocial factors represent culturally relevant resources that, through careful research, could ultimately be harnessed to promote better cognitive aging for a growing and increasingly diverse population of older adults., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Late-life marital status is associated with cognitive aging; however, the influence of life course marital biography (i.e., changes in marital status) on late-life cognitive trajectories, as well as gender differences in the effects of marital biography, remain to be explored. Associations between (a) marital status at study baseline (currently married, previously married, never married) and (b) retrospectively reported life course marital biography (i.e., age at first marriage, time spent unmarried following initial marriage, history of divorce, history of widowhood) and up to 20 years of subsequent episodic memory trajectories were examined using latent growth curve models in 3,061 participants aged 51 + in the Health and Retirement Study 2017 Life History Mail Survey. Gender differences were examined with multiplicative interaction terms and stratified models. Participants who were married at study baseline demonstrated higher initial memory than previously and never married individuals. Older age at first marriage and shorter duration spent unmarried were each associated with better initial episodic memory among previously married individuals only; longer duration spent unmarried was associated with slower memory decline. Stratified models suggested that these associations may be driven by women. These results highlight the importance of considering multiple aspects of marital biography, not just current marital status, in cognitive aging research. Marital biography may have an enduring influence on cognitive aging, particularly among previously married older women. Future work is needed to identify mechanisms (e.g., socioeconomic resources, cognitive stimulation, self and spousal health, emotional support) through which marital histories influence cognitive aging. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Objective: Racial/ethnic disparities in cognitive aging are only partly attributable to socioeconomic indicators. Psychosocial factors, such as discrimination and perceived control, also differ across racial/ethnic groups, and emerging literature highlights their potential role in contributing to cognitive disparities in addition to socioeconomic status. Method: 1,463 older adults (51% Hispanic, 27% non-Hispanic Black, and 22% non-Hispanic White) in the Washington Heights-Inwood Columbia Aging Project completed cognitive and psychosocial measures, including a comprehensive neuropsychological battery, Everyday and Major Experiences of Lifetime Discrimination scales, and the Perceived Control scale. Mediation models quantified separate indirect effects of Black race and Hispanic ethnicity on global cognitive composite scores through education, income, discrimination, and external perceived control. Results: Educational attainment, income, and perceived control each mediated racial/ethnic disparities in global cognition. Socioeconomic indicators (i.e., lower education and lower income) explained approximately 50% of the Black-White and Hispanic-White disparities in global cognition, and more external perceived control explained an additional 5%-8%. Hispanics reported the lowest levels of discrimination, while non-Hispanic Blacks reported the highest levels. However, neither everyday nor major lifetime discrimination was associated with global cognition. Significant racial/ethnic disparities in global cognition remained after accounting for the included socioeconomic and psychosocial factors. Conclusions: This study suggests that psychosocial factors may explain racial/ethnic disparities in cognitive aging above and beyond socioeconomic indicators. More external perceived control, which could reflect chronic exposure to interpersonal and institutional marginalization, may be a particularly salient psychosocial risk factor for poorer cognitive aging among non-Hispanic Black and Hispanic older adults. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Objectives: The composition of one's social network has been associated with cognition such that a greater proportion of family is associated with worse cognition compared to a greater proportion of friends. It is not clear whether this association between network composition and cognitive aging is driven by potential negative effects of family interactions or positive effects of friend interactions. Methods: Using the Health and Retirement Study (T1: 2006/2008, T2: 2010/2012, T3: 2012/2014), a longitudinal mediation model was conducted to test the effects of composition on episodic memory and latent change in memory through contact frequency with friends and family. Results: Analyses revealed indirect effects of composition on both T2 memory and latent change in memory through contact frequency with friends. A greater proportion of family in one's network was associated with lower contact frequency with friends and in turn lower memory. Composition was also associated with higher contact frequency with family; however, contact frequency with family was not associated with memory. Conclusions: These findings suggest that spending time with family may not affect episodic memory in older adulthood, but spending time with friends may be beneficial. Potential mechanisms and implications regarding the importance of friendships in later life are discussed.

Educational attainment is associated with cognition among older adults, but this association is complex and not well understood. While associated with better cognition among healthy adults, more education predicts faster decline in older adults with cognitive impairment. Education may influence cognitive functioning through mechanisms involving brain maintenance (BM: reduced age-related pathology) or cognitive reserve (CR: altered pathology-cognition association). We examined evidence for each mechanism by quantifying main and interaction effects of education within a well-studied pathway involving systolic blood pressure, white matter hyperintensities (WMH), and episodic memory in 2 samples without dementia at the baseline (total N = 1136). There were no effects of education on systolic blood pressure or WMH, suggesting a lack of evidence for BM. In the sample less likely to progress to dementia, education attenuated the effect of WMH on memory at the baseline. In the sample more likely to progress to dementia, education exacerbated this effect at the baseline. These moderations provide evidence for a CR mechanism and are consistent with previous findings of faster decline once CR is depleted., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objectives: Low educational attainment is a risk factor for more rapid cognitive aging, but there is substantial variability in cognitive trajectories within educational groups. The aim of this study was to determine the factors that confer resilience to memory decline within educational strata., Methods: We selected 2573 initially nondemented White, African American, and Hispanic participants from the longitudinal community-based Washington Heights/Inwood Columbia Aging Project who had at least two visits. We estimated initial memory (intercept) and the rate of memory decline (slope) using up to five occasions of measurement. We classified groups according to the educational attainment groups as low (≤5 years), medium (6-11 years), and high (≥12 years). We used a multiple-group latent growth model to identify the baseline predictors of initial memory performance and rate of memory decline across groups. The model specification considered the influence of demographic, socioeconomic, biomedical, and cognitive variables on the intercept and the slope of memory trajectory., Results: Our results indicated that the three educational groups do not benefit from the same factors. When allowed to differ across groups, the predictors were related to cognitive outcomes in the highly educated group, but we found no unique predictor of cognition for the low educated older adults., Conclusions: These findings highlight that memory-protective factors may differ across older adults with distinct educational backgrounds, and the need to evaluate a broader range of potential resilience factors for older adults with few years of school.

Older Black and Hispanic adults report more religious involvement, and religious involvement has been linked to better cognition. This study examined which aspects of religious involvement are associated with better longitudinal episodic memory and whether religious involvement offsets racial and ethnic inequalities in episodic memory. Using Health and Retirement Study data ( N = 16,069), latent growth curves estimated independent indirect pathways between race and ethnicity and 6-year memory trajectories through religious attendance, private prayer, and religious belief, controlling for nonreligious social participation, depressive symptoms, chronic health diseases, age, education, and wealth. Negative direct effects of Black race and Hispanic ethnicity on memory were partially offset by positive indirect pathways through more private prayer and religious attendance. While results were significant for memory intercept and not subsequent memory change, religious attendance and private prayer were independently associated with better cognitive health among diverse older adults. Findings may inform culturally relevant intervention development to promote successful aging and reduce older adults' cognitive morbidity.

Growing evidence supports a link between locus of control and memory in older adults. Control beliefs may directly predict larger hippocampal volume (i.e., brain maintenance). Alternatively, control beliefs may be associated with smaller hippocampal volume at any given level of memory (i.e., cognitive reserve). Multivariable regression analyses examined associations between verbal episodic memory, locus of control and hippocampal volume among 236 non-demented older adults in the community-based Washington Heights-Inwood Columbia Aging Project. Control beliefs were negatively associated with hippocampal volume when controlling for memory performance, indicating that individuals with stronger control beliefs were able to maintain memory function in the face of lower hippocampal volume. Subsequent exploratory models stratified by race/ethnicity indicated that this association was more prominent among racial/ethnic minorities (particularly Caribbean Hispanic older adults) than among non-Hispanic White older adults. Control beliefs were not associated with hippocampal volume before memory was taken into account. Results are consistent with the view that control beliefs facilitate the maintenance of memory function despite hippocampal volume loss. Results are not consistent with the view that locus of control contributes to brain maintenance. Culturally-appropriate interventions are needed to test whether strengthening control beliefs provides cognitive resistance to neuropathology.

Objectives: Cross-sectional and longitudinal evidence from largely non-Hispanic White cohorts suggests that positive psychosocial factors, particularly self-efficacy and social support, may protect against late-life cognitive decline. Identifying potentially protective factors in racial/ethnic minority elders is of high importance due to their increased risk of Alzheimer's disease. The overall goal of this study was to characterize cross-sectional associations between positive psychosocial factors and cognitive domains among Black, Hispanic, and White older adults., Methods: A total of 548 older adults (41% Black, 28% Hispanic, 31% White) in the Washington Heights-Inwood Columbia Aging Project completed cognitive and psychosocial measures from the NIH Toolbox and standard neuropsychological tests. Multiple-group regressions were used to compare cross-sectional associations between positive psychosocial factors and cognition across racial/ethnic groups, independent of demographics, depressive symptoms, and physical health., Results: Positive associations between self-efficacy and language did not significantly differ across race/ethnicity, although the bivariate association between self-efficacy and language was not significant among Hispanics. Additional positive associations were observed for Whites and Blacks, but not Hispanics. Negative associations between emotional support and purpose in life and working memory were seen only in Hispanics., Conclusions: Results confirm and extend the link between self-efficacy and cognition in late life, particularly for White and Black older adults. Previous studies on positive psychosocial factors in cognitive aging may not be generalizable to Hispanics. Longitudinal follow-up is needed to determine whether negative relationships between certain psychosocial factors and cognition in Hispanics reflect reverse causation, threshold effects, and/or negative aspects of having a strong social network. (JINS, 2018, 24, 294-304).

Objective: We aimed to whether the abnormally high amyloid-β (Aβ) level in the brain among apparently healthy elders is related with subtle cognitive deficits and/or accelerated cognitive decline., Methods: A total of 116 dementia-free participants (mean age 84.5 years) of the Washington Heights Inwood Columbia Aging Project completed 18F-Florbetaben PET imaging. Positive or negative cerebral Aβ deposition was assessed visually. Quantitative cerebral Aβ burden was calculated as the standardized uptake value ratio in pre-established regions of interest using cerebellar cortex as the reference region. Cognition was determined using a neuropsychological battery and selected tests scores were combined into four composite scores (memory, language, executive/speed, and visuospatial) using exploratory factor analysis. We examined the relationship between cerebral Aβ level and longitudinal cognition change up to 20 years before the PET scan using latent growth curve models, controlling for age, education, ethnicity, and Apolipoprotein E (APOE) genotype., Results: Positive reading of Aβ was found in 41 of 116 (35%) individuals. Cognitive scores at scan time was not related with Aβ. All cognitive scores declined over time. Aβ positive reading (B = -0.034, p = 0.02) and higher Aβ burden in temporal region (B = -0.080, p = 0.02) were associated with faster decline in executive/speed. Stratified analyses showed that higher Aβ deposition was associated with faster longitudinal declines in mean cognition, language, and executive/speed in African-Americans or in APOE ε4 carriers, and with faster memory decline in APOE ε4 carriers. The associations remained significant after excluding mild cognitive impairment participants., Conclusions: High Aβ deposition in healthy elders was associated with decline in executive/speed in the decade before neuroimaging, and the association was observed primarily in African-Americans and APOE ε4 carriers. Our results suggest that measuring cerebral Aβ may give us important insights into the cognitive profile in the years prior to the scan in cognitively normal elders.