HDL particle subpopulations: Focus on biological function.

Low levels of high-density lipoprotein-cholesterol (HDL-C) constitute an independent biomarker of cardiovascular morbi-mortality. However, recent advances have drastically modified the classical and limited view of HDL as a carrier of 'good cholesterol', and have revealed unexpected levels of complexity in the circulating HDL particle pool. HDL particles are indeed highly heterogeneous in structure, intravascular metabolism and biological activity. This review describes recent progress in our understanding of HDL subpopulations and their biological activities, and focuses on relationships between the structural, compositional and functional heterogeneity of HDL particles.

Radial augmentation index is a surrogate marker of atherosclerotic burden in a primary prevention cohort.

Arterial stiffness is linked to cardiovascular risk and predicts clinical events independently of peripheral blood pressure. The potential relationship between the augmentation index measured at the radial artery and asymptomatic atherosclerosis remains unclear however. In order to assess relationship between the peripheral augmentation index and traditional risk factors, we estimated cardiovascular risk and presence of subclinical atherosclerosis in a large asymptomatic population in primary prevention. Patients in primary prevention (n = 1007) with at least 1 cardiovascular risk factor were included and radial augmentation index was measured. Maximum common carotid intima-media thickness, the presence of plaque and Framingham 10 year cardiovascular risk score were assessed. The mean augmentation index was 81 ± 13% in a population composed of 55% males (mean age 56 years). The augmentation index differed significantly between men (77 ± 12%) and women (86 ± 12%). In the global population, augmentation index was negatively correlated to height and weight, and positively correlated to cardiovascular risk, age, systolic blood pressure, pulse pressure, diabetes, HDL-Cholesterol, fasting glucose, intima-media thickness and to the presence of plaques. Multivariate analysis in the global and in the male population revealed an independent and positive relationship between augmentation index and intima-media thickness on the one hand, and between augmentation index and the presence of plaque on the other. Our results confirm that there are significant relationships between a surrogate marker of arterial stiffness and subclinical atherosclerosis in a large primary prevention population.