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, an indicator of HDL functionality, and Pulse Wave Velocity (PWV), an indicator of arterial stiffness, in healthy subjects. Methods and Results - 151 healthy subjects (45 males, 106 females) underwent serum cholesterol efflux capacity measurement (aqueous diffusion and ATP binding cassette A1 (ABCA1)-dependent cholesterol efflux) and carotid-femoral PWV with a high-fidelity tonometer. In the unadjusted model, PWV relates directly with aqueous cholesterol diffusion (R2= 0.021, P= 0.039) and indirectly with ABCA1-dependent cholesterol efflux (R2= 0.045, P= 0.009). In a stepwise multivariate analysis including age, body mass index, mean arterial pressure, serum low density lipoprotein and HDL levels, fasting plasma glucose, ABCA1-dependent cholesterol efflux, and aqueous cholesterol diffusion, the best PWV predictors were mean arterial pressure (B= 0.66, 95%CI 0.048-0,085), age (B= 0.039, 95%CI 0.022-0.055) and ABCA1-dependent cholesterol efflux (B= -0.232, 95%CI -0.405--0.059). Conclusions – The finding that ABCA1-dependent cholesterol efflux capacity, but not serum HDL levels, is a significant predictor of PWV in healthy subjects points to the relevance of HDL function in vascular modeling and arterial stiffness prevention along life.