Abdominal volume index. an anthropometry-based index for estimation of obesity is strongly related to impaired glucose tolerance and type 2 diabetes mellitus

Our objective was to develop an anthropometric-based index (abdominal volume index, AVI) for estimating overall abdominal volume and to determine its relationship with presence of impaired glucose tolerance (IGT) and type 2 diabetes mellitus (DM). We conducted a cross-sectional, population-based study between November 1998 and June 2001 among 746 men and non-pregnant women randomly recruited from Durango City in northern Mexico. AVI was calculated using volume formulas for cylinder (V = πr2h) and vertical cone V = (1/3)πr2h. The formula developed was AVI = [2 cm (waist)2 + 0.7 cm (waist-hip)2]/1,000, which estimates overall abdominal volume between symphysis of pubis and xiphoid appendix and theoretically includes intra-abdominal fat and adipose tissue volumes. Receiver operating curve (ROC) scatter plot showed as best cut-off value of AVI for estimation of obesity, corresponding to 24.5 liters (L). Logistic regression analysis adjusted by age and sex showed higher odds ratio between AVI and IGT 1.6 (95% confidence interval [95% CI] 1.1–9.1, p = 0.01) as well as between AVI and DM 2.1 (95% CI 1.3–7.9, p = 0.001) than odds ratio (OR) estimated by other anthropometric obesity criteria such as waist-to-hip ratio, body mass index, truncated cone, and waist circumference. AVI is a reliable and easy-to-calculate anthropometric tool for estimation of overall abdominal volume that is shown to be strongly related to IGT and DM.