N-terminal prohormone B-type natriuretic peptide and cardiovascular function in Africans and Caucasians: The SAfrEIC study

Background: This study compared NT-proBNP levels and the association with cardiovascular markers between Africans and Caucasians from South Africa. Methods: This cross-sectional study involved 201 Africans and 255 Caucasians from the North West province, South Africa. Serum NT-proBNP concentrations, blood pressure, pulse wave velocity and arterial compliance were measured. Results: NT-proBNP levels were significantly higher (P<0.001) in Africans than Caucasians, also after adjusting for gender, body mass index (BMI) and pulse wave velocity (P=0.008). This significant difference became borderline significant after adjusting for systolic blood pressure (SBP) (P=0.060), and non-significant after adjusting for arterial compliance (P=0.35). In single regression, a significant positive correlation of NT-proBNP with SBP (r=0.26; P<0.001) and pulse pressure (PP) (r=0.28; P<0.001) were shown for Africans only. After multiple adjustments, the associations of NT-proBNP with SBP and PP remained significant in Africans (SBP: β=0.187, P<0.01; PP: β=0.234, P<0.001), with no significant associations in Caucasians. Conclusions: NT-proBNP levels were higher in Africans than Caucasians, independently of BMI and gender. This difference was partly driven by higher SBP and lower arterial compliance in Africans. NT-proBNP was persistently associated with SBP and PP in Africans, but not in Caucasians. These associations may suggest early vascular changes contributing to cardiac alterations in Africans.