VISCERAL ADIPOSITY: DISCORDANCE BETWEEN ARTERIAL STIFFNESS AND PERIPHERAL WAVE REFLECTIONS: PP.34.361

Abstract

Objective: Excess body fat accumulation is considered to be a determinant of arterial stiffness, as expressed by increased carotid - femoral pulse wave velocity (c-f PWV) and Augmentation index (Aix). However, in the context of visceral obesity, the relationship between Aix and c-f PWV is less well established. We sought to evaluate the influence of abdominal fat distribution, as reflected by abdominal fat index (AFI) on arterial stiffness and peripheral wave reflections. Design and Method: We studied 185 newly diagnosed, utreated, non diabetic, essential hypertensive subjects (aged =57 ± 10 years, male=96, office blood pressure=156/92 mm Hg, waist circumference=89 ± 13 cm). In all participants anthropometric data were recorded and venous blood sampling was performed to determine their metabolic profile. Aortic stiffness was evaluated on the basis of c-f PWV by means of a computerized method (Complior SP). Heart rate-corrected augmentation index (AIx75) was estimated as a measure of wave reflections. Ultrasonography was used for the assessment of abdominal fat distribution. Subcutaneous (S) and preperitoneal (P) fat layers were measured at their maximum and minimum thickness sites on the upper median abdomen. AFI was calculated as Pmax to Smin ratio. Results: Excess visceral adiposity as expressed by increased AFI was negatively correlated with Aix75 (r = - 0.28, p = 0.04) and positively with c-f PWV, glomerular filtration rate, triglycerides and homocysteine levels (r = +0.18 p = 0.44, r = +0.32 p = 0.02, r = +0.16 p = 0.04, r = +0.28 p = 0.79, respectively). On multiple regression analysis, 57% of the variance in AIx75 was carried out with the following significant predictors: age, smoking, glucose, mean systolic blood pressure and waist circumference. Conclusions: In the seting of essential hypertension, excess of visceral adiposity is associated with increased arterial stiffness but decreased peripheral wave reflections.