Abstract WP482: Early Life Exposure to the Stroke Belt and Later Life Incident Cognitive Impairment: The Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Abstract

Introduction: Incidence of cognitive impairment is higher for residents of the Stroke Belt (SB) compared to those living outside it, but the importance of timing of SB residence is unclear. Methods: Participants were aged 45+ yrs, and enrolled in 2003-2007 in REGARDS. Cognition was assessed annually, by telephone, using the Six-Item Screener (SIS) in 11,488 black or white stroke-free participants currently living in the SB, and 8,949 currently living outside of the SB. Incident cognitive impairment was defined as SIS score of < 4 at last assessment among participants with initial SIS >4. Exposures were defined as SB residence all years, some years, or no years of childhood (ages 0-18) and early adulthood (ages 19-30). Demographic adjusted logistic regression models were stratified by SB residence at enrollment, and were used to estimate the demographic-adjusted odds of incident cognitive impairment. Results: Among those currently residing in the SB, childhood residence outside the SB for some (OR = 0.82; 95% CI: 0.68 - 0.99) or all (OR = 0.76; 95% CI: 0.65 - 0.90) of the time predicted lower odds of incident cognitive impairment. Similarly, early adulthood residence outside the SB for some (OR = 0.86; 95% CI: 0.74 - 0.98) or all (OR = 0.70; 95% CI: 0.58 - 0.84) of the time predicted lower incident cognitive impairment. Conversely, for those currently living outside the SB, the risk of incident cognitive impairment was higher for those who had spent their entire early adulthood in the SB (OR = 1.51; 95% CI: 1.01 - 2.57), with non-significant increased risk for childhood exposure or some early adulthood exposure to the SB (table). Conclusions: These findings suggest that early residence in the SB during childhood or early adulthood increases the risk of cognitive impairment regardless of place of residence in later adulthood. Further research is needed to determine the characteristics of early SB life that are linked to later adult cognitive impairment.