Clearance approach in hyperinsulinemic-euglycemic clamp evaluation in lean and obese subjects

Abstract Purpose/Aim: The main aim of this study was to propose a method to express whole body insulin sensitivity as estimated by a hyperinsulinemic-euglycemic clamp (HEC) as a dimensionless parameter. Materials and methods: Two groups of subjects were examined: The first group was comprised of seven healthy lean volunteers with BMI <25 kg/m(2) and a second group comprised of four obese subjects with BMI ≥30 kg/m(2). The dependence between the M/I index expressing the whole body insulin sensitivity, and the dimensionless whole human body effect E as a ratio of the clearance of glucose and the clearance of insulin after their exogenous administration during the last 40 min of the HEC test, was expressed by regression analysis. Unlike an expression of insulin sensitivity/resistance as a function of M taking into account the space corrections or the M/I index, our whole human body effect represents the insulin sensitivity/resistance as a dimensionless number. Results: A linear dependence between the M/I index and the dimensionless effect E with zero intercept and slope at 2.2623 ± 0.157, r = 0.914, and between the M/I index and the effect E recalculated per kg of human body weight with zero intercept and slope at 0.03164 ± 0.00127, r = 0.978, were observed. Conclusions: The high correlation between the M/I index and new effect E in lean and obese volunteers confirms our proposal that the HEC test could be evaluated by a dimensionless parameter which eliminates potential unit mismatches in the expression of clamp results.