Fat distribution and endothelial function in normal-overweight menopausal women.

Background: Adipose tissue is not an inert deposit of fat; in the truncal area, it seems to be metabolically active, due to the adipokines produced locally. These substances are related to insulin resistance, inflammation and atherosclerotic damage to the vascular system. The development of ultrasound methodologies enable better estimation of fat distribution and more detailed investigation of the metabolic aspects of the fat depots and their impact on the initial stages of atherosclerosis. Aim of the study: To investigate the influence of abdominal fat on endothelial function, the initial stages of atherosclerotic vascular damage and its relationship with inflammatory status in normaloverweight subjects [n. 162, body mass index (BMI) >25 kg ⁄m2 to <30 kg ⁄m2]. Methods: A total of 162 Caucasian postmenopausal women (mean age 54 ± 4 years, menopausal age 8 ± 4 years) were subdivided on the basis of the median value of the visceral fat distribution and associations with brachial flow-mediated vasoactivity (FMV), BMI, intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1), total and LDL cholesterol investigated. Results: Subjects with lower levels of visceral fat had a higher brachial FMV (7.9 ± 4.3 vs. 5Æ1 ± 3.2%, P < 0.05) and lower BMI, waist, sICAM- 1, sVCAM-1, total and LDL cholesterol. In univariate analyses, abdominal visceral fat showed a direct correlation with sICAM-1 (r = 0.43, P < 0.001), and an inverse correlation with FMV (r = -0.49, P < 0.01). Moreover an indirect relationship emerged between brachial FMV and sICAM-levels (r = -0.36, P < 0.05). In a multivariate analysis the predictive variables for brachial FMV were LDL cholesterol (b = -0.22, P < 0.05), visceral fat (b = -0.32, P < 0.05), sICAM-1 (b = -0.18, P < 0.05), HDL cholesterol (b = 0.25, P < 0.05) and brachial diameter (b = -0.27, P < 0.05). Subcutaneous fat and triglycerides were also included in the model. Conclusions: In Caucasian normal-overweight women, visceral fat thickness was directly associated with the level of soluble ICAM-1 and inversely with FMV, thereby showing its relevance to endothelial function and the inflammatory state.