Hdl Cholesterol Levels And Endothelial Glycocalyx Integrity In Treated Hypertensive Patients Over 40 Years Old

Objective: Endothelial dysfunction indicates target organ damage in hypertensive patients. The integrity of endothelial glycocalyx (EG) plays a vital role in vascular permeability, inflammation and elasticity and finally to cardiovascular disease. We aimed to investigate the role of increased HDL cholesterol levels (HDL-C), which usually are considered protective against cardiovascular disease, in EG integrity in middle aged hypertensive patients. Design and method: We studied 186 treated hypertensive patients, apparently healthy and older than 40 years. They were divided regarding sex distribution in two groups. In males’ group, HDL-C was 48 + 19 mg/dl (n = 77, mean age 51 + 11 years) while in females’ group, HDL-C was 67 + 16 mg/dl (n = 109, mean age 63 + 12 years). 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: Females were older (p = 0.04) with fewer smokers (p = 0.04), higher levels of office SBP (148 + 19 mmHg vs. 139 + 15 mmHg, p < 0.001) as well as higher HDL levels (p < 0.001). No differences were found within groups regarding BMI, DBP, total Cholestelol and PBR 5–9. In males, HDL-C was inversely related with PBR 5–9 (r = -0.29, p = 0.01). In a multiple linear regression analysis model, using smoking habit and office SBP levels, as independent variables, we found that HDL-C independently predicted PBR 5–9 (Beta = 0.25, p = 0.006) in male hypertensives. Conclusions: In middle-aged, apparently healthy, hypertensive patients, higher HDL-C levels protect EG and subsequently endothelial function. However, the role of EG as a novel index regarding cardiovascular risk in essential hypertension needs to be extensively investigated in future studies.