Lifecourse Residential Segregation, Ethnic Enclaves and Risk and Resilience to ADRD in Diverse Cohorts - PROJECT SUMMARY (ABSTRACT) As the population ages, the prevalence and risk for Alzheimer’s disease and related dementia (ADRD) is expected to increase with even greater risk for Blacks and Hispanic/Latinx groups. Historical and contemporary structural racism in the form of residential segregation is a fundamental cause of health disparities that may contribute to ADRD inequities. However, residential segregation in some communities may inadvertently lead to formation of ethnic enclaves where higher concentration and proportion of some ethnic groups may be protective against the negative effects of segregation. Some studies found that higher residential segregation is associated with greater cognitive decline and higher risk for ADRD, but other found that it may be protective. It is unclear how lifecourse residential segregation is associated with cognitive decline and risk for ADRD. This project will determine the relationship of lifecourse residential segregation with ADRD using measures of incident ADRD, cognition and neuroimaging brain biomarkers. Furthermore, we will explore how education and poverty rates may mediate the relationship of segregation and ADRD risk. We will use data from the KHANDLE and STAR cohort studies, two longitudinal cohort studies of racial/ethnically diverse participants of older-adults residing in the Northern California area. Measures of residential segregation indices of evenness, exposure, concentration, centralization, and clustering will be derived from decennial census data from 1970s to 2010s and linked with historical addresses of participants across 7 timepoints (birth, ages 5, 10, 18, 30, 40, 65). Causal inferences models will be used to (Aim 1) examine the association of lifecourse residential segregation and cognition for approximately 2476 participants and (Aim 3) examine 614 subset of participants with MRI markers of brain health. Mediation analysis (Aim 2) will be conducted for educational quality and attainment, and poverty rates to assess the impact of proximal and distal social determinants of health on the relationship between residential segregation and late-life cognition. As of current, this is the first study to our knowledge that will examine the lifecourse timing and duration of residential segregation with cognitive decline and risk for ADRD in multiple racial groups. This study present opportunities to comprehensively assess the effects of lifecourse residential segregation, significantly improving our understanding of structural racism on late-life cognitive outcomes and ADRD. Findings from this study may inform decision-making policies on equitable home lending, and neighborhood reform for healthy cognitive aging. With the support of an exemplary team of experts, the applicant will be trained and enhanced with skills, research proficiency, and rigorous methodology needed to carry out this project and advanced his career as a researcher on health disparities.
