Risk factors for stroke in blacks: a critical review.

Stroke is the third leading cause of death in US Blacks and is an important cause of mortality and morbidity worldwide. Mortality rates are higher in Blacks than in Whites in the United States at ages below 70 years. In Blacks, advanced age, elevated blood pressure, diabetes mellitus, and smoking are the only risk factors for stroke whose status has been firmly established by published data. More data are needed to assess other likely risk factors of importance for risk stratification and intervention and to determine the fraction of racial differences in stroke that may be explained by risk factor differences. Higher prevalences of hypertension, diabetes, obesity (in women), elevated lipoprotein(a) level, smoking (in men), and low socioeconomic status may contribute to the higher stroke incidence and mortality in US Blacks as compared with Whites. However, further environmental influences must be studied and candidate genes identified before assuming that racial differences can be attributed to inborn susceptibility linked to inheritance of specific genes.