P2.54 Influence of Central Obesity on Early Carotid Intima-Media Thickening is Independent of that from Other Risk Factors

Abstract

Its unknown if obesity or its associated risk factors influence early vascular change.

Methods

We investigated if anthropometric measurements, body mass index [BMI], waist/hip ratio [WHR], waist circumference [Wc] and Waist/ height ratio WHTR, or metabolic parameters (glucose, insulin, lipid, uric acid and blood pressure {BP}) correlated more with Carotid intima-media thickness (IMT), vascular stiffness [Augmentation Index] and brachial artery reactivity). 100 Subjects (71F, 29M) without vascular events, BP <140/90, LDL < 4 mmol/l, glucose < 6.2 mmol/l participated.

Results

BMI, WHR, WC, WHTR correlated significantly with triglyceride, HDL, LDL, insulin, glucose, uric acid and BP levels (p< 0.001). IMT correlated with WHTR, BMI, WC, Glucose (p<0.001), Homeostasis Index (HOMA) and Cholesterol levels (p<0.05). Only Age, WHTR or BMI were significant correlates of IMT in a multivariate analysis (MVA) (p<0.01) including WHTR or BMI, with age, sex, SBP, HDLc and HOMA. Augmentation Index correlated with age (p<0.0001), WHTR and WC (p<0.0005) but with age only in a MVA. Vascular reactivity did not correlate with any anthropometric or metabolic parameters. Anthropometric cut off points, (BMI <25, WC <102cm M, <88cm F, WHR <0.9 M, <0.8 F, and WHTR < 0.5) significantly differenciated normal from abnormal metabolic and vascular measurements. The WHTR ratio < 0.5 was as reliable as the BMI cut-off < 25 in determining metabolic and vascular abnormalities. BMI and WHTR were strongly associated with 89% agreement (p<0.0001). These results demonstrated that anthropometric and metabolic parameters correlated, but anthropometric parameters were the significant correlates of vascular change. A waist/height ratio > 0.5 predicts both early vascular and metabolic changes. These data support a risk factor independent vasculotrophic effect of obesity.