The role of Southern context in shaping life course exposures linked to dementia incidence for Black and White older adults in the United States.

While racial inequities in dementia risk are well-documented in the United States, research has paid less attention to role of US Southern context in shaping dementia risk through life course exposures. In this study, we examine how Southern birth and Southern residence in adulthood are linked to dementia incidence for Black and White older adults in the United States. Using the Health and Retirement Study (N = 15,613), we estimate a series of hazard models to evaluate how life course risk factors such as childhood health and social disadvantage, education, adult socioeconomic status, health behaviors, and cardiometabolic conditions impact the association between Southern life course residency and dementia risk. We find different patterns in how Southern life course context shapes dementia risk among Black and White adults, with dementia risk among Blacks especially sensitive to combinations of Southern life course context. These findings demonstrate the importance of considering potential heterogenous life course pathways to cognitive aging and health that may be shaped by larger socio-historical experiences.