The association between apolipoproteins and arterial stiffness in young adults: the AfricanPREDICT study

Abstract

Motivation: South Africa is facing a high burden of non-communicable diseases with cardiovascular disease (CVD) being the largest contributor. Changes in vascular structure and function, even at an early age, contributes to the future development of CVD. Dyslipidaemia is traditionally defined asincreased low-density lipoprotein cholesterol and decreased high-density lipoprotein cholesterol levels and is strongly related to vascular changes and CVD development. Ethnic differences in the traditional lipid profile are well documented, with white populations tending to present with a more atherogenic profile, characterised by increased low-density lipoprotein cholesterol and decreased high-density lipoprotein cholesterol. In addition to the the tradiotional lipid markers, the use of apolipoproteins as risk markers for CVD is showing increased credibility in recent studies. Evidence regarding associations between apolipoproteins and the development of changes within the vasculature are limited and whether any ethnic differences are at play also remains to be determined.Aim: Our study aimed to investigate whether differences in apolipoproteins are evident in a young, apparently healthy bi-ethnic population and whether apolipoproteins are associated with arterial stiffness in each ethnic group. Methods: This study included 1162 young, apparently healthy black and white, men and women from the African-PREDICT study. Measures of vascular structure and function were determined including: pulse wave velocity (PWV), augmentation index (AIx), central pulse pressure (cPP) and carotid intima-media thickness (cIMT). Apolipoprotein B (Apo B) and apolipoprotein A-1 (Apo A-1) were determined from serum samples and a Apo B/ Apo A-1 ratio was calculated. Results and conclusion: We found that Apo B, Apo B/Apo A-1 and Apo A-1 were all higher in the white group (all P<0.030) as compared to the black group. Apolipoprotein B was independently associated with cPP (β=0.16, P<0.027) and cIMT (β=0.19, P<0.022) and Apo B inversely associated with PWV (β=-0.15, P<0.025) in the black group. No associations between the vascular markers and any of the apolipoproteins were found in the white group. In conclusion, the results indicate that apolipoproteins may play an important role in the early changes of the vasculature in young, black South Africans.