Association between birth in the stroke belt and late‐life cognition with assessment of socioeconomic and cardiovascular risk factors: The Study of Healthy Aging in African Americans (STAR)

Abstract

AbstractBackgroundThe Southeastern U.S. (“Stroke Belt”) is known for high rates of cardiovascular diseases and cognitive impairment. Due to the high proportion of Black Americans born in the Stroke Belt and their elevated risk of cognitive impairment, we examined the relationship of birth in a Stroke Belt state with late‐life cognition in The Study of Healthy Aging in African Americans (STAR).MethodSTAR evaluated cognition in African Americans (N=764) ages 50+ who were long‐term Kaiser Permanente Northern California members. Participants completed Multiphasic Health Check‐ups (1964‐1985) at which early adulthood cardiovascular risk factors (CVRF) of body mass index, blood pressure, glucose, and total cholesterol were measured. At STAR wave 1 (2018), participants self‐reported birth state (all participants resided in northern California by the 1980s), childhood and young adulthood socioeconomic status (SES), and completed cognitive assessments using the Spanish and English Neuropsychological Assessment Scales (SENAS). We used linear regression to estimate the association between Stroke Belt birth state with cognition adjusting for birth year, gender, and parental education and evaluating SES and CVRF as potential mediators.ResultAfter exclusions for missing data, 27% (n=197) of 728 participants were born in a Stroke Belt state and mean age at cognitive assessment was 69 years (SD=9). Birth in a Stroke Belt state was associated with worse late‐life executive function (β(95% CI): ‐0.18(‐0.33, ‐0.02)) and semantic memory (β(95% CI): ‐0.37(‐0.53, ‐0.21)), but not verbal episodic memory, compared to individuals born elsewhere. Having 2+ SES risk factors (β(95% CI): ‐0.77(‐0.97, ‐0.56)) or 2+ CVRF (β(95% CI): ‐0.20(‐0.37, ‐0.03)) was associated with significantly worse executive function compared to having no SES or cardiovascular risk factors, respectively. Additionally, having 2+ SES risk factors (β(95% CI): ‐0.64(‐0.85, ‐0.43)) was associated with worse semantic memory. Associations of birth in a Stroke Belt state with executive function (β(95% CI): ‐0.07(‐0.23, 0.08)) and semantic memory (β(95% CI): ‐0.30(‐0.47, ‐0.14)) were attenuated after adjusting for SES and cardiovascular risk factors simultaneously (as well as individually).ConclusionBirth in a Stroke Belt state has lasting influence on cognitive function that is only partially mediated by childhood and early adulthood SES and cardiovascular risk factors.