Project Summary/Abstract Alzheimer’s Disease and Alzheimer’s Disease Related Dementias (AD/ADRD) are on the rise in the United States. Estimates project a 40% increase in AD among older Americans by 2025. This increase, along with its associated economic, social, and health burdens, are likely to have disproportionate impacts, as Black adults have the highest incidence of dementia of any racial/ethnic group in the U.S. Moreover, Black Americans experience higher rates of established biological risk factors for AD/ADRD, including hypertension, diabetes, stroke, inflammation, and biological aging. The expected growth in AD diagnoses, expenditures, and burdens, as well as potentially widening racial inequalities, make it imperative to investigate early risk factors for the development of AD/ADRD and racial inequalities in AD/ADRD. Structural forms of racism are likely important drivers of racial inequalities in AD/ADRD risk. Yet, much of the research in this area focuses on downstream factors, such as exposure to stressors and discrimination, or specific domains of structural racism at one point in time. Missing are longitudinal studies of structural racism and aging-related health inequalities across multiple geographic contexts. Further, there is limited knowledge of how public health and policy interventions addressing structural racism can be utilized to reduce racial inequalities in AD/ADRD. Causal modeling techniques provide opportunities to assess the impact of structural interventions on documented inequalities in biological risk factors for AD/ADRD using observational data. The purpose of this project is twofold: 1) to create a public-use, comprehensive data repository of multilevel and repeated contextual measures of structural racism; and 2) use the new contextual data in combination with existing contextual and individual-level longitudinal data from the National Longitudinal Study of Adolescent to Adult Health (Add Health) to examine specific pathways linking structural racism and AD/ADRD biological risk among early midlife U.S. adults. Specifically, we will investigate whether structural racism across educational, residential, and criminal justice contexts independently and jointly shape Black-White disparities in biological risk factors for AD/ADRD, including hypertension, diabetes, inflammation, epigenetic aging, and two novel biomarkers of AD/ADRD risk (neurofilament light and total tau). We will also use simulation models to compare the effects of hypothetical population-based policy changes and targeted interventions on racial inequalities in biological risk factors of AD/ADRD risk. Findings from this study will advance our understanding of how structural racism shapes AD/ADRD risk early in the life course. Results from simulation models will also inform the development of population-level, early interventions aimed to slow the progression of AD/ADRD risk and reduce health inequalities in these outcomes.

Project Narrative Longitudinal studies of structural racism and resulting inequalities in risk factors for Alzheimer’s Disease and Alzheimer’s Disease Related Dementias (AD/ADRD) are rare, especially in young adulthood. Additionally, effective population-level policies and interventions targeting structural racism to reduce racial inequalities in biological risk factors for AD/ADRD are sparse. The proposed study will create a database of multilevel, repeated, and prospective measures of structural racism; investigate the extent to which structural racism in education, residential, and criminal justice contexts shape Black-White inequalities in AD/ADRD risk; and use causal modeling techniques to evaluate the impact of structural interventions on documented racial inequalities in biological risk factors for AD/ADRD.