Body fat distribution and flow-mediated endothelium-dependent vasodilation in older men.

Abstract

Recent studies indicate that abdominal fat accumulation, in particular intra-abdominal fat, is related to impaired endothelial function in young healthy volunteers. The aim of this study was to examine whether the distribution of body fat depots is related to impaired endothelial function in older men. Cross-sectional sample of 38 older (68+/-1 y) sedentary (VO(2max)=2.4+/-0.1 l/min) men. Flow-mediated endothelial dependent vasodilation (EDD) was assessed in the brachial artery in response to reactive hyperemia using high-resolution ultrasound. Abdominal subcutaneous and visceral fat depots were assessed by computed tomography scan (CT-scan) at the L(4)-L(5) region in the supine position. Percentage body fat was assessed via dual-energy X-ray absorptiometry (DEXA). Flow-mediated percentage change in brachial artery was 7.6+/-0.7%, suggesting an impaired flow-mediated EDD. Using simple linear regression analysis, there were no statistically significant relationship observed between flow-mediated EDD and the indices of total and abdominal adiposity (percentage body fat=29.3+/-0.9%, r=-0.11; total abdominal fat area=465+/-23 cm(2), r=-0.1; intra-abdominal fat area=200+/-14 cm(2), r=-0.14; subcutaneous fat area=265+/-13 cm(2), r=-0.05; BMI=29.3+/-0.9 kg/m(2), r=-0.07; and waist to hip ratio=0.98+/-0.01, r=-0.20). These findings suggest that in older sedentary men there is no clear correlation between adiposity and body fat distribution and impairment of flow-mediated endothelium dependent vasodilation.