Racial disparity in stroke risk factors: the Berlin-Ibadan experience; a retrospective study

Different workers have reported racial disparities in the distribution of risk factors for stroke and stroke subtype (ischemic vs hemorrhagic). No transcultural transnational studies have been conducted to confirm and relate these disparities to one another. Our objective was to identify differences in the distribution of risk factors for stroke and stroke subtypes among urban-dwelling stroke patients in Nigeria, a developing country, and Germany, an industrialized country. Consecutive stroke patients in Ibadan (100) and Berlin (103) were studied. Their hospital records were screened to identify documented vascular risk factors and stroke subtype. The stroke patients in Ibadan were younger than those in Berlin (t = 4.940, P = 0.000). Hypertension was significantly more common in Ibadan while cigarette smoking, dyslipidemia, atherosclerosis, and cardiac factors were significantly more frequent in Berlin. Cerebral infarction was more common in Berlin (80%) than in Ibadan (63%). The risk factors associated with cerebral infarction were more frequent in Berlin. We suspect that racial disparity in risk factors for stroke may account for the difference in proportions of stroke subtype in black and white populations. Larger prospective community-based multinational multiracial studies are required to confirm these disparities and identify possible underlying genetic, dietary, and socio-economic factors.