In elderly women moderate hypercholesterolemia is associated to endothelial and microcirculatory impairments

Abstract

How cholesterol influences the microcirculation on aging subjects is not well known. This study evaluated moderate hypercholesterolemia effects in, treated or not, lean elderly women on brachial artery reactivity and microcirculatory function using venous occlusion plethysmography (VOP) and nailfold videocapillaroscopy (NVC). Patients (mean age 73years) were divided into healthy elderly (HE, n=15), treated dyslipidemia with statins during at least 6months (TDL, n=9) and dyslipidemia (DL, n=9, cholesterol, 257±11 and LDL-cholesterol, 157±24mg/dl). Young, mean age 23years, women (YC, n=24), served as controls. Laboratory and anthropometrical analysis, VOP peak forearm blood flow (FBF) during the reactive hyperemia response/baseline FBF (%HYPER) and peak FBF after 0.4mg sublingual nitroglycerin/baseline FBF (%NITRO) were assessed. NVC capillary density and diameters, maximum red blood cell velocity (RBCVmax) during reactive hyperemia/baseline RBCV and time to reach RBCVmax were evaluated. Correlations between %HYPER, %NITRO and plasma cholesterol fractions were performed.Total and LDL-cholesterol were increased only in DL group. Capillary diameters were larger in elderly groups than YC. RBCVmax/baseline RBCV was reduced in the DL group compared to HE, TDL and YC. %HYPER was lower in DL and normalized in TDL group. YC %HYPER was double of HE. %NITRO decreased from (HE=YC) to TDL and DL groups. There was a significant inverse correlation between LDL-cholesterol, non-HDL-cholesterol and %HYPER/% Nitro. In conclusion, moderate hypercholesterolemia reversibly impaired the vasodilatatory response in the microcirculation but the endothelial-independent vasodilator response to nitroglycerine remained irreversibly lower in healthy aged women.