PROJECT SUMMARY The rapid increase in the population with Alzheimer?s disease and related dementias (ADRD) in the United States constitutes a looming public health crisis. Dementia is a syndrome of progressive cognitive impairment and a leading cause of disability, loss of independence, institutionalization, and death in older adults. ADRD affect more than 5 million U.S. adults over age 65, but also impact an estimated 16 million family and friends who, as primary caregivers, are at increased risk of poor physical and mental health and social isolation. The prevalence of dementia is expected to increase as the population ages, and there is currently no known treatment that can cure or substantially slow its progression. A top public health priority, therefore, is to determine how to improve the lives of persons living with dementia (PWD) in order reduce the impact of dementia on PWD and their caregivers. Features of the neighborhood social, physical, built, and service environment may provide necessary support to PWD and their caregivers, or, alternatively, exacerbate the adverse impacts of dementia. The proposed study will determine how neighborhood-based supportive factors (e.g., meal delivery, home health care, amenities, walkability) and stressors (e.g., lack of safety, disorder, noise, traffic) affect health and well- being among PWD and their caregivers. We leverage data from two large, nationally representative, and longitudinal surveys that have collected information on thousands of PWD and their caregivers and provide information on their place of residence: the Health and Retirement Study (HRS) and the National Health and Aging Trends Study (NHATS). We will first create a national, longitudinal database of neighborhood characteristics that, as indicated by theory and research, reflect opportunities for physical activity, social engagement, and mental stimulation, supportive services and resources, and psychosocial stressors. Using this new data resource, which will be made available to the research community, we will estimate the impact of neighborhood-level factors on multiple dimensions of health and well-being (e.g., frailty, social engagement, institutionalization) for both PWD and their caregivers. We will further determine if health and well-being vary across groups defined by race/ethnicity, socioeconomic status, living alone, and residence in urban/rural areas and assess the role of the neighborhood in generating this inequality. To our knowledge, this will be the first empirical study to examine, in a national context, how neighborhoods can engender quality of life in PWD and their caregivers. The proposed study is timely because an increasing number of cities and communities are engaged in efforts to become more dementia-friendly. This project will identify aspects of neighborhoods and communities that support living well with dementia and inform policies and programs to reduce the costs and burden of dementia on individuals, families, and communities.