Abstract P554: Multiple Social Determinants of Health and Incident Stroke in the Reasons for Geographic and Racial Differences in Stroke Study

Abstract

Introduction: Although social determinants of health (SDOH) were shown to be individually associated with incident stroke, few studies explored the effect of multiple SDOH within the same individuals on incident stroke. To address this limitation, we operationalized SDOH as a count and examined its association with incident stroke. This approach is practically appealing in clinical settings - it is easy to calculate and interpret. Hypothesis: We hypothesized that a greater number of SDOH within individuals would be significantly associated with a higher risk of incident stroke. Methods: REGARDS is a prospective cohort of 30,239 black and white adults aged > 45 years recruited in 2003-2007. Sociodemographic, medical history, and stroke risk factors were collected at baseline. To define exposure, we followed the Healthy People 2020 framework, and initially used 10 SDOH to represent 5 domains: education, health, social, economic and neighborhood factors. We selected SDOH that were significantly associated with incident stroke: race, education, income, zip code poverty, health insurance, social isolation, and residence in states with poor public health infrastructure. We then created a primary exposure - a count of SDOH for each individual. The outcome was expert adjudicated incident strokes. Cox proportional hazards models examined associations between a count of SDOH (0, 1, 2, 3+) and incident stroke, adjusting for confounders. Results: This study included 27,813 individuals free from stroke at baseline. We observed 1470 incident strokes during the follow-up. A significant interaction between SDOH count and age resulted in stratification at 75 years. In fully adjusted Cox models, among individuals <75 years, risk of stroke amplified with each increase in number of SDOH. This pattern was not observed among those 75+ years (Table 1). Conclusions: Individuals <75 years with a greater number of SDOH had higher risk of stroke. Targeting individuals with multiple SDOH, especially those <75 years, may help reduce risk of stroke.