Racial differences in stroke and its associated risk factors remain partially understood, and there is a persistent disparity in mortality and incidence of stroke impacting Black Americans. Evidence suggests that Interleukin-6 mediates racial disparities in stroke through its association with traditional risk factors including heart disease, smoking, atrial fibrillation, hypertension, and diabetes. Only one reviewed biomarker, Lipoprotein(a), is a race-specific risk factor for stroke, which is about 80% genetically determined, and levels are substantially higher in Black than White people.
The overrepresentation of traditional risk factors explains about 50% of the excess stroke among Black people. In the United States, the Sickle Cell trait is relatively common in the Black population, with a prevalence of 9%, and about 1/601 Black newborns have the HbSS genotype. Black people have smaller Lp(a) isoforms and much higher Lp(a) than other race-ethnic groups. Although the Black-White disparities in stroke have been known for at least a half-century, only recently have studies focused on biological and genetic factors contributing to racial disparities in stroke.
Understanding the causes of these large disparities is the first step to design and implement interventions to reduce the unequal distribution of stroke’s public health burden. Further research is needed for the study of interactions amongst preclinical models, risk factors and social determinants of health, biomarkers, and origins of stroke risk factors by race.