INCREASED HDL CHOLESTEROL LEVELS RELATE TO ENDOTHELIAL GLYCOCALYX INTEGRITY IN OLDER TREATED PATIENTS WITH ESSENTIAL HYPERTENSION

Abstract

Objective: Endothelial dysfunction indicates target organ damage in patients with arterial hypertension. The integrity of endothelial glycocalyx (EG) plays a vital role in vascular permeability, inflammation and elasticity and finally to cardiovascular disease (CVD). We aimed to investigate the role of increased HDL cholesterol levels (HDL-C), which usually are considered protective against cardiovascular disease, in endothelial glycocalyx integrity in older healthy hypertensive patients. Design and method: One hundred-twenty (120) patients with arterial hypertension under treatment (mean age 66+9 years, females) and no history of previous cardiovascular disease were divided regarding HDL-C tertiles in two groups. In group HDLH, HDL-C was > 71 mg/dl (upper HDL-C tertile, n = 41, mean age 67+10 years, 6 males). In group HDLL, HDL-C was < 71 mg/dl (two lower HDL-C tertiles, n = 79, mean age 66+9 years, 45 males). Increased perfusion boundary region (PBR) of the sublingual arterial microvessels (ranged from 5–9 micrometers) using Sideview Darkfield imaging (Microscan, Glycocheck) was measured as a non-invasive accurate index of reduced EG thickness. Results: No significant differences were found within groups regarding age, central and brachial systolic and diastolic BP as well as PP, smoking habit, LDL-C levels and PWV. PBR 5–9 was significantly decreased in group HDLH (p = 0.04). In the whole population, HDL-C was inversely related with PBR 5–9 (r = -0.22, p = 0.01). In a multiple linear regression analysis model, using age, BMI, smoking habit, HDL-C, LDL-C and office SBP, as independent variables, we found that BMI (Beta = 0.25, p = 0.006) independently predicted PBR 5–9 in the whole population. Conclusions: We found that endothelial function, represented by EG levels, seems to be protected even in older hypertensive patients with extremely increased HDL-C levels and no history of cardiovascular disease. The possible role of EG, as a novel cardiovascular risk index in essential hypertension, needs to be further evaluated.