SERUM CHOLESTEROL EFFLUX CAPACITY INVERSELY CORRELATES WITH ARTERIAL STIFFNESS IN HEALTHY SUBJECTS

Objective – Little is known on the impact of HDL athero-protective properties on vascular remodeling in healthy subjects. We investigated the relationship between serum cholesterol efflux capacity (CEC), an indicator of HDL functionality, and Pulse Wave Velocity (PWV), an indicator of arterial stiffness, in healthy subjects. Methods and Results - 167 healthy subjects (54 males, 113 females) underwent serum CEC measurement (aqueous diffusion and ATP binding cassette A1 (ABCA1)-dependent cholesterol efflux) and carotid-femoral PWV with a high-fidelity tonometer. Both ABCA1-mediated CEC and PWV did not correlate with HDL-C levels, either as a whole group and as males and females separately. In an unadjusted model, PWV inversely correlated with ABCA1-dependent cholesterol efflux (r= 0.183, p-val = 0.018). No correlation was found between PWV and aqueous diffusion-dependent CEC (r = 0.129, p-val = 0.095). In a nested linear regression model, controlling for age, sex, body mass index, mean arterial pressure, serum low-density lipoprotein, HDL and glycated hemoglobin, PWV displays a significant negative regression on ABCA1-dependent CEC (β= -0.204, 95%CI -0.371/-0.037). The finding that ABCA1-dependent CEC, but not serum HDL cholesterol level, is a significant predictor of PWV in healthy subjects points to the relevance of HDL function in vascular physiology and arterial stiffness prevention along life.