Stroke Belt birth state and late-life cognition in the Study of Healthy Aging in African Americans (STAR).

Abstract Purpose We examined the association of Stroke Belt birth state with late-life cognition in The Study of Healthy Aging in African Americans (STAR). Methods STAR enrolled 764 Black Americans ages 50+ who were long-term Kaiser Permanente Northern California members. Participants completed Multiphasic Health Check-ups (MHC;1964-1985) where early-life overweight/obesity, hypertension, diabetes, and hyperlipidemia were measured. At STAR (2018), birth state, self-reported early-life socioeconomic status (SES), and executive function, verbal episodic memory, and semantic memory scores were collected. We used linear regression to examine the association between Stroke Belt birth and late-life cognition adjusting for birth year, gender, and parental education. We evaluated early-life SES and cardiovascular risk factors (CVRF) as potential mechanisms. Results Twenty-seven percent of participants were born in the Stroke Belt with a mean age of 69(SD=9) at STAR. Stroke Belt birth was associated with worse late-life executive function (β(95% CI):-0.18(-0.33,-0.02)) and semantic memory (-0.37(-0.53, -0.21)), but not verbal episodic memory (-0.04(-0.20, 0.12)). Adjustment for SES and CVRF attenuated associations of Stroke Belt birth with cognition (executive function (-0.05(-0.25, 0.14)); semantic memory (-0.28(-0.49, -0.07))). Conclusion Black Americans born in the Stroke Belt had worse late-life cognition than those born elsewhere, underscoring the importance of early-life exposures on brain health.