Protection from Cardiovascular Disease Due to Increased High-Density Lipoprotein Cholesterol in African Black Populations: Myth or Reality?

Abstract

The burden of cardiovascular disease (CVD) in sub-Saharan Africa has increased over the last decade. Despite this, African Black populations present with relatively low incidences of coronary heart disease and ischemic heart disease, which may be attributed to their lower total cholesterol, triglycerides and low-density lipoprotein cholesterol concentrations, compared with White populations. Commensurate with these lower lipid levels, it was believed that high-density lipoprotein cholesterol (HDL-C) concentrations would be higher in Black populations compared with their White counterparts. This is based on data from previous studies of African and African American populations; however, recent studies conducted in Africa found similar or lower HDL-C concentrations in Black compared with White individuals. Current research, therefore, suggests that HDL-C may not be a good indicator of cardiovascular risk and future research should focus on HDL quality (vs quantity), by measuring HDL functionality and subclass.

Keywords: African Population Studies; Cardiovascular Risk; High-Density Lipoprotein Cholesterol.

Figure 1.. Quality vs quantity of HDL

Despite equivalent concentrations of HDL-C, CVD risk may be different. This is related to improved HDL functionality, namely reverse cholesterol efflux, antioxidative, anti-inflammatory, anti-thrombotic and anti-apoptotic functions. Decreased CVD risk may be associated with shifts in HDL subclass distribution, with decreased HDL2 and increased HDL3. Increased CVD risk may be associated with dysfunctional HDL and a reduction in sphingosine-1-phosphate (S1P) content.