A comparison of cardiovascular disease risk factor biomarkers in African Americans and Yoruba Nigerians

Classical risk factors for coronary artery disease are changing in the developing world while rates of cardiovascular disease are increasing in these populations. Newer risk factors have been identified for cardiovascular disease, but these have been rarely examined in elderly populations and not those of developing countries.

This study was a cross-sectional comparison from a longitudinal, observational, epidemiologic study in which participants are interviewed at three-year intervals. The sample included 1510 African Americans from Indianapolis, Indiana, and 1254 Yoruba from Ibadan, Nigeria. We compared anthropomorphic measurements; biomarkers of endothelial dysfunction (plasminogen activator inhibitor type 1 [PAI-1 and E-selectin), inflammation (C-reactive protein), and lipid oxidation (8-isoprostane); and levels of lipids, homocysteine, folate, and vitamin B12.

Cholesterol, triglycerides, and low-density lipoprotein cholesterol levels were higher in African Americans. For markers of endothelial dysfunction, E-selectin and homocysteine differed between men, and PAI-1 was higher in the Yoruba. C-reactive protein differed only in women, but 8-isoprostane was higher in the Yoruba.

Higher lipid levels in African Americans are consistent with their Western diet and lifestyle. Oxidative stress appears to be higher in the Yoruba than in African Americans, which may be secondary to dietary differences. Whether these differences in classical and emerging risk factors account for the different rates of cardiovascular disease, dementia, or other morbidities in these two populations remains to be determined.