The waist-height ratio is a potential anthropometric index of insulin resistance: Observations based on oral glucose tolerance test in lean, normo-glycaemic, Asian Indian males from Southern India

Abstract

AimsTo correlate the waist-to-height ratio (WHt-R) with Matsuda index of the Oral Glucose Tolerance Test (OGTT) and other surrogate indices of fasting insulin resistance/sensitivity and to derive a cut-off value for the WHt-R in lean, normoglycaemic males from Southern India. MethodsA cohort of 105 lean, normoglycaemic males (mean BMI: 19.2 ± 2.6 kg/m2) underwent OGTT. Surrogate indices of insulin resistance viz, the Homeostatic model assessment of Insulin Resistance (HOMA-IR), the Quantitative Insulin sensitivity Check Index (QUICKI), the Fasting glucose to insulin ratio (FG-IR), the McAuley's index and the Triglyceride/HDL-C ratio were correlated with the Matsuda and the Insulinogenic indices. The cut-off value for WHt-R to predict insulin resistance was obtained using Receiver operating characteristics (ROC) with Area under curve (AUC) at 95% confidence interval (CI). The P value < 0.05 was considered statistically significant. ResultsThe ROC analysis at 95% confidence interval (CI), showed an AUC of 0.58 for the WHt-R cut-off value ≥ 0.39 with 69.4% sensitivity and 57.1% specificity. On pooled ROC analysis, significantly higher AUC was observed for the WHt-R (0.90) when compared to BMI (0.83) and waist-to-hip ratio (0.83). Paired wise comparison analysis of ROC curves revealed significant differences for AUC of WHt-R when compared to waist circumference (p < 0.01), but not for BMI and WHR. ConclusionThe WHt-R can be used as a potential anthropometric index to screen for insulin resistance, when compared to BMI and WC in lean, normoglycaemic males from Southern India.