Abstract 30: Black On Black: Stroke Outcomes In Foreign Vs. Us Born Individuals Of African Ancestry

Introduction: Black individuals are disproportionally affected by stroke, yet little is known about the effect of region of origin and acculturation on stroke mortality. We examined associations between nativity and stroke outcomes among Black individuals in the US. Methods: Using the National Health Interview Service 2000-2014 data and mortality linked files through 2015, we identified participants aged 25-74 years who self-identified as Black (n=64,717). We categorized Black race by birth region, i.e. foreign-born (Caribbean, South and Central American, and African) vs. US-born. Stroke was determined by self-report. Using Cox regression, we examined the association between nativity and all-cause, cardiovascular (CV), and stroke mortality, adjusting for age, sex, education, income, smoking, and body mass index, overall and by time since migration. Results: Overall, 4329 deaths (including 205 stroke and 932 CV deaths) were recorded during the study period. Weighted cumulative incidence of all-cause, CV, and stroke mortality at 10 years follow up were 12.62%, 2.76%, and 0.59% for those born in the US; 6.12%, 1.58%, and 0.45% for those born in the Caribbean, South and Central America; and 3.15%, 0.54%, and 0.08% for those born in Africa. In the model adjusted for demographic factors, compared to US-born Black individuals, rates of all cause and CV mortality were lower among Black individuals born in the Caribbean, South and Central America [all-cause mortality: aHR (95%CI): 0.46 (0.38-0.55); CV mortality [0.60 (0.40-0.89)], but rates of stroke mortality were similar [1.00 (0.55-1.99)]. African-born Black individuals had lower all-cause mortality rates [0.50 (0.32-0.80)] and trended toward having lower CV [0.47 (0.20-1.13)] mortality rates compared to those born in the US. The above findings remained similar after adjusting for smoking and BMI. Time since migration did not significantly affect mortality outcomes among foreign born Blacks. Conclusion: Foreign-born Black individuals generally have lower all cause and CV mortality regardless of time since migration. These findings highlight the need for more granular information regarding region of origin and acculturation to understand and target racial disparities.