Childhood and Adulthood Trauma Associate With Cognitive Aging Among Black and White Older Adults.

Sociocontextual factors powerfully shape risk for age-related cognitive impairment, including excess risk burdening medically underserved populations. Lifecourse adversity associates with cognitive aging, but harms are likely mitigable. Understanding population-salient relationships and sensitive periods for exposure is crucial for targeting clinical interventions. OBJECTIVE: The authors examined childhood and adulthood traumatic events in relation to cognition among Black and White older adults in the Health and Retirement Study (HRS). PARTICIPANTS: Participants (N = 13,952) aged 55+ had complete lifetime trauma and cognitive testing data at the 2006/08, 2010/12, and/or 2014/16 waves. MEASURES: Trauma indices comprised childhood and adulthood event counts. Outcomes included baseline performance and trajectories on the Telephone Interview for Cognitive Status. DESIGN: Main and nonlinear trauma effects were modeled via linear regression, and overall contributions assessed with omnibus likelihood ratio tests. RESULTS: Black participants (N = 2,345) reported marginally lower adulthood trauma exposure than White participants (N = 11,607) with no other exposure differentials observed. In White participants only, greater childhood trauma exposure predicted worse baseline cognition but slower change over time. Across race, adulthood trauma robustly associated with baseline cognition. Relationships were frequently nonlinear: low but nonzero trauma predicted highest cognitive scores, with much poorer cognition observed as trauma exposure increased. Relationships between adulthood trauma and trajectory were limited to the White sample. CONCLUSION: Traumatic experiences, particularly in adulthood, may impact late-life cognitive health if not addressed. Findings highlight foci for clinical researchers and providers: adverse life events as a source of cognitive risk, and identification of community-specific resources that buffer behavioral, physical, and mental health sequelae of previous and incident trauma.

Association between military service and Alzheimer's disease neuropathology at autopsy.

INTRODUCTION: Anti-amyloid therapies are at the forefront of efforts to treat Alzheimer's disease (AD). Identifying amyloid risk factors may aid screening and intervention strategies. While veterans face increased exposure to risk factors, whether they face a greater neuropathologic amyloid burden is not well understood. METHODS: Male decedents donating to two Alzheimer's Disease Research Center (ADRC) brain banks from 1986 to 2018 with categorized neuritic plaque density and neurofibrillary tangles (n = 597) were included. Using generalized ordered logistic regression we modeled each outcome's association with military history adjusting for age and death year. RESULTS: Having served in the military (60% of sample) is associated with post mortem neuritic amyloid plaque (for each comparison of higher to lower C scores OR = 1.26; 95% confidence interval [CI] = 1.06-1.49) and tau pathology (B score OR = 1.10; 95% CI = 1.08-1.12). DISCUSSION: This is the first study, to our knowledge, finding increased levels of verified AD neuropathology in those with military service. Targeted veteran AD therapies is a pressing need.

The structural and social determinants of Alzheimer's disease related dementias.

INTRODUCTION: The projected growth of Alzheimer's disease (AD) and AD-related dementia (ADRD) cases by midcentury has expanded the research field and impelled new lines of inquiry into structural and social determinants of health (S/SDOH) as fundamental drivers of disparities in AD/ADRD. METHODS: In this review, we employ Bronfenbrenner's ecological systems theory as a framework to posit how S/SDOH impact AD/ADRD risk and outcomes. RESULTS: Bronfenbrenner defined the "macrosystem" as the realm of power (structural) systems that drive S/SDOH and that are the root cause of health disparities. These root causes have been discussed little to date in relation to AD/ADRD, and thus, macrosystem influences, such as racism, classism, sexism, and homophobia, are the emphasis in this paper. DISCUSSION: Under Bronfenbrenner's macrosystem framework, we highlight key quantitative and qualitative studies linking S/SDOH with AD/ADRD, identify scientific gaps in the literature, and propose guidance for future research. HIGHLIGHTS: Ecological systems theory links structural/social determinants to AD/ADRD. Structural/social determinants accrue and interact over the life course to impact AD/ADRD. Macrosystem is made up of societal norms, beliefs, values, and practices (e.g., laws). Most macro-level determinants have been understudied in the AD/ADRD literature.

Global rural health disparities in Alzheimer's disease and related dementias: State of the science.

INTRODUCTION: Individuals living in rural communities are at heightened risk for Alzheimer's disease and related dementias (ADRD), which parallels other persistent place-based health disparities. Identifying multiple potentially modifiable risk factors specific to rural areas that contribute to ADRD is an essential first step in understanding the complex interplay between various barriers and facilitators. METHODS: An interdisciplinary, international group of ADRD researchers convened to address the overarching question of: "What can be done to begin minimizing the rural health disparities that contribute uniquely to ADRD?" In this state of the science appraisal, we explore what is known about the biological, behavioral, sociocultural, and environmental influences on ADRD disparities in rural settings. RESULTS: A range of individual, interpersonal, and community factors were identified, including strengths of rural residents in facilitating healthy aging lifestyle interventions. DISCUSSION: A location dynamics model and ADRD-focused future directions are offered for guiding rural practitioners, researchers, and policymakers in mitigating rural disparities. HIGHLIGHTS: Rural residents face heightened Alzheimer's disease and related dementia (ADRD) risks and burdens due to health disparities. Defining the unique rural barriers and facilitators to cognitive health yields insight. The strengths and resilience of rural residents can mitigate ADRD-related challenges. A novel "location dynamics" model guides assessment of rural-specific ADRD issues.

Predictors of Willingness to Enroll in Hypothetical Alzheimer Disease Biomarker Studies that Disclose Personal Results.

INTRODUCTION: We examined factors related to willingness to enroll in hypothetical Alzheimer disease (AD) biomarker studies. METHODS: Using linear regression, we assessed the relationship among enrollment willingness and demographics, family dementia history, research attitudes, concern about AD, experiences of discrimination, and belief in AD risk modifiability. Inductive coding was used to assess qualitative data. RESULTS: In middle-aged and older adult AD research participants (n=334), willingness to enroll in biomarker studies was driven by biomarker collection method, research attitudes, and disclosure of personal results. Predictors of willingness were similar for Black and White participants. Themes associated with increased willingness included a desire to learn biomarker results and support research. DISCUSSION: Research attitudes were an important predictor of biomarker study willingness regardless of race. As seen elsewhere, Black participants were more hesitant to participate in biomarker research. Disclosure of biomarker results/risk can bolster willingness to enroll in biomarker studies, particularly for Black participants.

Alzheimer's disease biomarkers in Black and non-Hispanic White cohorts: A contextualized review of the evidence.

Black Americans are disproportionately affected by dementia. To expand our understanding of mechanisms of this disparity, we look to Alzheimer's disease (AD) biomarkers. In this review, we summarize current data, comparing the few studies presenting these findings. Further, we contextualize the data using two influential frameworks: the National Institute on Aging-Alzheimer's Association (NIA-AA) Research Framework and NIA's Health Disparities Research Framework. The NIA-AA Research Framework provides a biological definition of AD that can be measured in vivo. However, current cut-points for determining pathological versus non-pathological status were developed using predominantly White cohorts-a serious limitation. The NIA's Health Disparities Research Framework is used to contextualize findings from studies identifying racial differences in biomarker levels, because studying biomakers in isolation cannot explain or reduce inequities. We offer recommendations to expand study beyond initial reports of racial differences. Specifically, life course experiences associated with racialization and commonly used study enrollment practices may better account for observations than exclusively biological explanations.

Addressing the disparities in dementia risk, early detection and care in Latino populations: Highlights from the second Latinos & Alzheimer's Symposium.

The Alzheimer's Association hosted the second Latinos & Alzheimer's Symposium in May 2021. Due to the COVID-19 pandemic, the meeting was held online over 2 days, with virtual presentations, discussions, mentoring sessions, and posters. The Latino population in the United States is projected to have the steepest increase in Alzheimer's disease (AD) in the next 40 years, compared to other ethnic groups. Latinos have increased risk for AD and other dementias, limited access to quality care, and are severely underrepresented in AD and dementia research and clinical trials. The symposium highlighted developments in AD research with Latino populations, including advances in AD biomarkers, and novel cognitive assessments for Spanish-speaking populations, as well as the need to effectively recruit and retain Latinos in clinical research, and how best to deliver health-care services and to aid caregivers of Latinos living with AD.

Perspectives of Veterans Affairs mental health providers on working with older adults with dementia and their caregivers.

Continuing education directed at building providers' skills and knowledge in geriatrics represents a practical approach to addressing the geriatric mental health (MH) care workforce shortage. To inform the development of professional training curricula, we surveyed MH providers (N = 65) at a Veterans Affairs medical center on working with older persons with dementia (PwD) and informal caregivers. Providers rated service provision to PwD and caregivers as highly important but endorsed modest self-efficacy. Half of respondents were minimally confident in managing risk of harm to self or others in a PwD. Respondents believed PwD can benefit from MH treatments, yet identified several barriers to providing care, including inadequate time and staffing resources. Interest in geriatric training topics was high. Findings demonstrate that MH providers at this site value care provision to PwD and caregivers, and desire additional training to serve this population. System-level barriers to MH care for PwD should also be identified and addressed.

Depressive role impairment and subthreshold depression in older black and white women: race differences in the clinical significance criterion.

OBJECTIVES: We examined race differences in the DSM-IV clinical significance criterion (CSC), an indicator of depressive role impairment, and its impact on assessment outcomes in older white and black women with diagnosed and subthreshold depression. DESIGN: We conducted a secondary analysis of a community-based interview study, using group comparisons and logistic regression. SETTING: Lower-income neighborhoods in a Midwestern city. PARTICIPANTS: 411 community-dwelling depressed and non-depressed women ≥ 65 years (45.3% Black; mean age = 75.2, SD = 7.2) recruited through census tract-based telephone screening. MEASUREMENTS: SCID interview for DSM-IV to assess major depression and dysthymia; Center for Epidemiologic Studies-Depression Scale to define subthreshold depression (≥16 points); Mini-Mental State Examination, count of medical conditions, activities of daily living, and mental health treatment to assess health factors. RESULTS: Black participants were less likely than Whites to endorse the CSC (11.8% vs. 24.1%; p = .002). There were few race differences in depressive symptom type, severity, or count. Blacks with subthreshold depression endorsed more symptoms, though this comparison was not significant after adjustments. Health factors did not account for race differences in CSC endorsement. Disregarding the CSC-eliminated differences in diagnosis rate, race was a significant predictor of CSC endorsement in a logistic regression. CONCLUSIONS: Race differences in CSC endorsement are not due to depressive symptom presentations or health factors. The use of the CSC may lead to underdiagnosis of depression among black older adults. Subthreshold depression among Blacks may be more severe compared to Whites, thus requiring tailored assessment and treatment approaches.

Association between enrollment factors and incident cognitive impairment in Blacks and Whites: Data from the Alzheimer's Disease Center.

INTRODUCTION: We examined the influence of enrollment factors demonstrated to differ by race on incident mild cognitive impairment and dementia using Alzheimer's Disease Center data. METHODS: Differences in rates of incident impairment between non-Latino Whites and Blacks (n = 12,242) were examined with age-at-progression survival models. Models included race, sex, education, source of recruitment, health factors, and family history of dementia. RESULTS: No significant race differences in progression were observed in cognitively unimpaired participants. In those with mild cognitive impairment at baseline, Whites evidenced greater risk for progression than Blacks. Enrollment factors, for example, referral source, were significantly related to progression. DISCUSSION: The finding that Blacks demonstrated lower rate of progression than Whites is contrary to the extant literature. Nested-regression analyses suggested that selection-related factors, differing by race, may account for these findings and influence our ability to accurately estimate risk for progression. It is potentially problematic to make racial comparisons using Alzheimer's Disease Center data sets.

Work Disability Among Native-born and Foreign-born Americans: On Origins, Health, and Social Safety Nets.

Public debates about both immigration policy and social safety net programs are increasingly contentious. However, little research has explored differences in health within America's diverse population of foreign-born workers, and the effect of these workers on public benefit programs is not well understood. We investigate differences in work disability by nativity and origins and describe the mix of health problems associated with receiving Social Security Disability Insurance benefits. Our analysis draws on two large national data sources-the American Community Survey and comprehensive administrative records from the Social Security Administration-to determine the prevalence and incidence of work disability between 2001 and 2010. In sharp contrast to prior research, we find that foreign-born adults are substantially less likely than native-born Americans to report work disability, to be insured for work disability benefits, and to apply for those benefits. Overall and across origins, the foreign-born also have a lower incidence of disability benefit award. Persons from Africa, Northern Europe, Canada, and parts of Asia have the lowest work disability benefit prevalence rates among the foreign-born; persons from Southern Europe, Western Europe, the former Soviet Union, and the Caribbean have the highest rates.

A Framework for Assessing the Effects of Climate Change on Dementia Risk and Burden.

Alzheimer's disease and related dementias (ADRD) represent a public health crisis poised to worsen in a changing climate. Substantial dementia burden is modifiable, attributable to risk rooted in social and environmental conditions. Climate change threatens older populations in numerous ways, but implications for cognitive aging are poorly understood. We illuminate key mechanisms by which climate change will shape incidence and lived experiences of ADRD, and propose a framework for strengthening research, clinical, and policy actions around cognitive health in the context of climate change. Direct impacts and indirect risk pathways operating through built, social, interpersonal, and biomedical systems are highlighted. Air pollution compromises brain health directly and via systemic cardiovascular and respiratory ailments. Flooding and extreme temperatures constrain health behaviors like physical activity and sleep. Medical care resulting from climate-related health shocks imposes economic and emotional tolls on people living with dementia and caregivers. Throughout, inequitable distributions of climate-exacerbated risks and adaptive resources compound existing disparities in ADRD incidence, comorbidities, and care burden. Translational research, including work prioritizing underserved communities, is crucial. A mechanistic framework can guide research questions and methods and identify clinical- and policy-level intervention loci for prevention and mitigation of climate-related impacts on ADRD risk and burden.

Associations of sleep duration and daytime sleepiness with plasma amyloid beta and cognitive performance in cognitively unimpaired, middle-aged and older African Americans.

STUDY OBJECTIVES: Given the established racial disparities in both sleep health and dementia risk for African American populations, we assess cross-sectional and longitudinal associations of self-report sleep duration (SRSD) and daytime sleepiness with plasma amyloid beta (Aß) and cognition in an African American (AA) cohort. METHODS: In a cognitively unimpaired sample drawn from the African Americans Fighting Alzheimer's in Midlife (AA-FAiM) study, data on SRSD, Epworth Sleepiness Scale, demographics, and cognitive performance were analyzed. Aß40, Aß42, and the Aß42/40 ratio were quantified from plasma samples. Cross-sectional analyses explored associations between baseline predictors and outcome measures. Linear mixed-effect regression models estimated associations of SRSD and daytime sleepiness with plasma Aß and cognitive performance levels and change over time. RESULTS: One hundred and forty-seven participants comprised the cross-sectional sample. Baseline age was 63.2 ±â€…8.51 years. 69.6% self-identified as female. SRSD was 6.4 ±â€…1.1 hours and 22.4% reported excessive daytime sleepiness. The longitudinal dataset included 57 participants. In fully adjusted models, neither SRSD nor daytime sleepiness is associated with cross-sectional or longitudinal Aß. Associations with level and trajectory of cognitive test performance varied by measure of sleep health. CONCLUSIONS: SRSD was below National Sleep Foundation recommendations and daytime sleepiness was prevalent in this cohort. In the absence of observed associations with plasma Aß, poorer self-reported sleep health broadly predicted poorer cognitive function but not accelerated decline. Future research is necessary to understand and address modifiable sleep mechanisms as they relate to cognitive aging in AA at disproportionate risk for dementia. CLINICAL TRIAL INFORMATION: Not applicable.

Disparities in 30-day readmission rates among Medicare enrollees with dementia.

BACKGROUND: Readmissions contribute to excessive care costs and burden for people living with dementia. Assessments of racial disparities in readmissions among dementia populations are lacking, and the role of social and geographic risk factors such as individual-level exposure to greater neighborhood disadvantage is poorly understood. We examined the association between race and 30-day readmissions in a nationally representative sample of Black and non-Hispanic White individuals with dementia diagnoses. METHODS: This retrospective cohort study used 100% Medicare fee-for-service claims from all 2014 hospitalizations nationwide among Medicare enrollees with dementia diagnosis linked to patient, stay, and hospital factors. The sample consisted of 1,523,142 hospital stays among 945,481 beneficiaries. The relationship between all cause 30-day readmissions and the explanatory variable of self-reported race (Black, non-Hispanic White) was examined via generalized estimating equations approach adjusting for patient, stay, and hospital-level characteristics to model 30-day readmission odds. RESULTS: Black Medicare beneficiaries had 37% higher readmission odds compared to White beneficiaries (unadjusted OR 1.37, CI 1.35-1.39). This heightened readmission risk persisted after adjusting for geographic factors (OR 1.33, CI 1.31-1.34), social factors (OR 1.25, CI 1.23-1.27), hospital characteristics (OR 1.24, CI 1.23-1.26), stay-level factors (OR 1.22, CI 1.21-1.24), demographics (OR 1.21, CI 1.19-1.23), and comorbidities (OR 1.16, CI 1.14-1.17), suggesting racially-patterned disparities in care account for a portion of observed differences. Associations varied by individual-level exposure to neighborhood disadvantage such that the protective effect of living in a less disadvantaged neighborhood was associated with reduced readmissions for White but not Black beneficiaries. Conversely, among White beneficiaries, exposure to the most disadvantaged neighborhoods associated with greater readmission rates compared to White beneficiaries residing in less disadvantaged contexts. CONCLUSIONS: There are significant racial and geographic disparities in 30-day readmission rates among Medicare beneficiaries with dementia diagnoses. Findings suggest distinct mechanisms underlying observed disparities differentially influence various subpopulations.

Wisconsin Healthcare Utilization Cost Among American Indians/Alaska Natives with and without Alzheimer's Disease and Related Dementias.

Individuals with Alzheimer's disease and related dementias (ADRD) accrue higher healthcare utilization costs than peers without ADRD, but incremental costs of ADRD among American Indians/Alaska Natives (AI/AN) is unknown. State-wide paid electronic health record data were retrospectively analyzed using percentile-based bootstrapped 95% confidence intervals of the weighted mean difference of total 5-year billed costs to compare total accrued for non-Tribal and Indian Health Service utilization costs among Medicaid and state program eligible AI/AN, ≥40 years, based on the presence/absence of ADRD (matching by demographic and medical factors). AI/AN individuals with ADRD accrued double the costs compared to those without ADRD, costing an additional $880.45 million to $1.91 billion/year.

Effect of Metabolic Syndrome Risk Factors on Processing Speed and Executive Function in Three Racialized Groups.

BACKGROUND: Metabolic syndrome (MetS) has been associated with increased risk for Alzheimer's disease and related dementias (ADRD). Understanding the association of MetS risk factors to processing speed and executive function in the pre-clinical stages of ADRD in under-represented groups would offer insight on potential mechanisms through which MetS associates with ADRD risk. OBJECTIVE: Examine association of MetS features and processing speed and executive function across three racial groups. METHODS: Cognitively unimpaired adults from the Wisconsin Alzheimer's Disease Research Center and the Wisconsin Registry for Alzheimer's Disease Prevention completed blood-draws and neuropsychological testing. Six cognitive outcomes were assessed in association to MetS risk factors: Trailmaking Tests A and B, Animal Fluency, Digit Symbol, and composite scores for Processing Speed and Executive Function. Linear mixed effect models were used to assess the relationship between MetS risk factor count and longitudinal cognitive performance across three racialized groups. RESULTS: Participant sample sizes varied by outcome analyzed (N = 714-1,088). African American and Native American groups exhibited higher rates of MetS than non-Hispanic Whites. MetS was associated with processing speed and executive function across all racialized groups. Three-way interaction by racialized group was limited to one cognitive outcome: Trailmaking Test A. CONCLUSION: Metabolic dysfunction incrementally affects cognitive trajectory, with generally similar associations across racial groups. Since racialized groups exhibit higher levels of both MetS and ADRD, MetS may represent a driving factor for increased ADRD risk experience by racialized group and an important and modifiable target through which to reduce risk of ADRD.

Associations between self-reported sleep patterns and health, cognition and amyloid measures: results from the Wisconsin Registry for Alzheimer's Prevention.

Previous studies suggest associations between self-reported sleep problems and poorer health, cognition, Alzheimer's disease pathology and dementia-related outcomes. It is important to develop a deeper understanding of the relationship between these complications and sleep disturbance, a modifiable risk factor, in late midlife, a time when Alzheimer's disease pathology may be accruing. The objectives of this study included application of unsupervised machine learning procedures to identify distinct subgroups of persons with problematic sleep and the association of these subgroups with concurrent measures of mental and physical health, cognition and PET-identified amyloid. Dementia-free participants from the Wisconsin Registry for Alzheimer's Prevention (n = 619) completed sleep questionnaires including the Insomnia Severity Index, Epworth Sleepiness Scale and Medical Outcomes Study Sleep Scale. K-means clustering analysis identified discrete sleep problem groups who were then compared across concurrent health outcomes (e.g. depression, self-rated health and insulin resistance), cognitive composite indices including episodic memory and executive function and, in a subset, Pittsburgh Compound B PET imaging to assess amyloid burden. Significant omnibus tests (P < 0.05) were followed with pairwise comparisons. Mean (SD) sample baseline sleep assessment age was 62.6 (6.7). Cluster analysis identified three groups: healthy sleepers [n = 262 (42.3%)], intermediate sleepers [n = 229 (37.0%)] and poor sleepers [n = 128 (20.7%)]. All omnibus tests comparing demographics and health measures across sleep groups were significant except for age, sex and apolipoprotein E e4 carriers; the poor sleepers group was worse than one or both of the other groups on all other measures, including measures of depression, self-reported health and memory complaints. The poor sleepers group had higher average body mass index, waist-hip ratio and homeostatic model assessment of insulin resistance. After adjusting for covariates, the poor sleepers group also performed worse on all concurrent cognitive composites except working memory. There were no differences between sleep groups on PET-based measures of amyloid. Sensitivity analyses indicated that while different clustering approaches resulted in different group assignments for some (predominantly the intermediate group), between-group patterns in outcomes were consistent. In conclusion, distinct sleep characteristics groups were identified with a sizable minority (20.7%) exhibiting poor sleep characteristics, and this group also exhibited the poorest concurrent mental and physical health and cognition, indicating substantial multi-morbidity; sleep group was not associated with amyloid PET estimates. Precision-based management of sleep and related factors may provide an opportunity for early intervention that could serve to delay or prevent clinical impairment.

Plasma Aß42/40 and cognitive variability are associated with cognitive function in Black Americans: Findings from the AA-FAIM cohort.

Introduction: It is critical to develop more inclusive Alzheimer's disease (AD) research protocols to ensure that historically excluded groups are included in preclinical research and have access to timely diagnosis and treatment. If validated in racialized groups, plasma AD biomarkers and measures of subtle cognitive dysfunction could provide avenues to expand diversity in preclinical AD research. We sought to evaluate the utility of two easily obtained, low-burden disease markers, plasma amyloid beta (Aß)42/40, and intra-individual cognitive variability (IICV), to predict concurrent and longitudinal cognitive performance in a sample of Black adults. Methods: Two hundred fifty-seven Black participants enrolled in the African Americans Fighting Alzheimer's in Midlife (AA-FAIM) study underwent at least one cognitive assessment visit; a subset of n = 235 had plasma samples. Baseline IICV was calculated as the standard deviation across participants' z scores on five cognitive measures: Rey Auditory Verbal Learning Test Delayed Recall, Trail Making Test Parts A and B (Trails A and B), and Boston Naming Test. Using mixed effects regression models, we compared concurrent and longitudinal models to baseline plasma Aß42/40 or IICV by age interactions. PrecivityAD assays quantified baseline plasma Aß42/40. Results: IICV was associated with concurrent/baseline performance on several outcomes but did not modify associations between age and cognitive decline. In contrast, plasma Aß42/40 was unrelated to baseline cognitive performance, but a pattern emerged in interactions with age in longitudinal models of Trails A and B and Rey Auditory Verbal Learning Test total learning trials. Although not significant after correcting for multiple comparisons, low Aß42/40 was associated with faster cognitive declines over time. Discussion: Our results are promising as they extend existing findings to an Black American sample using low-cost, low-burden methods that can be implemented outside of a research center, thus supporting efforts for inclusive AD biomarker research.

Traversing the Aging Research and Health Equity Divide: Toward Intersectional Frameworks of Research Justice and Participation.

Meaningful reductions in racial and ethnic inequities in chronic diseases of aging remain unlikely without major advancements in the inclusion of minoritized populations in aging research. While sparse, studies investigating research participation disparities have predominantly focused on individual-level factors and behavioral change, overlooking the influence of study design, structural factors, and social determinants of health on participation. This is also reflected in conventional practices that consistently fail to address established participation barriers, such as study requirements that impose financial, transportation, linguistic, and/or logistical barriers that disproportionately burden participants belonging to minoritized populations. These shortcomings not only risk exacerbating distrust toward research and researchers, but also introduce significant selection biases, diminishing our ability to detect differential mechanisms of risk, resilience, and response to interventions across subpopulations. This forum article examines the intersecting factors that drive both health inequities in aging and disparate participation in aging research among minoritized populations. Using an intersectional, social justice, and emancipatory lens, we characterize the role of social determinants, historical contexts, and contemporaneous structures in shaping research accessibility and inclusion. We also introduce frameworks to accelerate transformative theoretical approaches to fostering equitable inclusion of minoritized populations in aging research.

Psychological well-being and cognitive aging in Black, Native American, and White Alzheimer's Disease Research Center participants.

Psychological well-being is associated with cognition in later life but has not been examined across diverse populations-including minoritized communities at disproportionately high risk of dementia. Further, most previous work has not been able to examine links between specific facets of psychological well-being and performance within distinct cognitive domains that can capture subclinical impairment. Using a well-characterized sample followed through enrollment in an NIH-funded Alzheimer's Disease Center, we sought to test these associations within three racial groups at baseline. Participants were N = 529 cognitively unimpaired Black, American Indian/Alaska Native (AI/AN), and white middle-aged and older adults (mean age = 63.6, SD = 8.1, range = 45-88 years) enrolled in the Wisconsin Alzheimer's Disease Research Center's Clinical Core. Predictors included validated NIH Toolbox Emotion Battery scales assessing positive affect, general life satisfaction, and meaning and purpose. Outcomes included performance on widely used tests of executive functioning and episodic memory. We conducted race-stratified regression models to assess within-group relationships. Black and AI/AN participants reported lower life satisfaction than white participants. Racial disparities were not observed for positive affect or meaning and purpose scores. Across groups, life satisfaction predicted better executive functioning. Similar associations were observed for positive affect in Black and AI/AN samples but not among whites. In general, well-being measures were not related to performance on tests of episodic memory. Our results highlight well-being as a potentially important determinant of late-life cognitive health, particularly executive functioning, that is modifiable if older adults are connected with appropriate resources and supports. Further, psychological well-being may represent a potent target for brain health interventions tailored for Black and Native communities.