Glucose effectiveness and insulin sensitivity measurements derived from the non-insulin-assisted minimal model and the clamp techniques are concordant

Abstract

Background: We investigated the concordance between glucose effectiveness (SG) and insulin sensitivity (SI), derived from the unmodified dynamic non-insulin-assisted intravenous glucose tolerance test (IVGTT) implemented by SGMM and SIMM; simulation analysis and modelling/conversational interaction (SAAM/CONSAM) versus the eu/hyperglycaemic basal insulinaemic and the euglycaemic hyperinsulinaemic clamp (SGCLAMP and SICLAMP). Methods: Twenty-seven of 30 normoglycaemic subjects completed a (1) euglycaemic hyperinsulinaemic clamp, (2) 6-h eu/hyperglycaemic nearnormoinsulinaemic pancreatic clamp with hyperglycaemia present over the final 2 h of the clamp (Day 2 study), (3) identical clamp to (2) but with euglycaemia maintained over the entire 6 h (Day 3 study) and (4) IVGTT. SGCLAMP was calculated in two ways based on data from study (2) alone (Day 2 SGCLAMP 210-240́) or from data from study day (2) and (3) (Day 2-3 SGCLAMP 330-360́). Results: SGMM was unrelated to the magnitude of endogenous insulin release (AIR). The single-day (Day 2) and two-day (Day 2 and 3) SGCLAMP protocols correlated (r = 0.72, p = 0.003), but SGCLAMP 210-240́ was significantly (p = 0.001) higher than SGCLAMP 330-360́. Employing the Day 2 and 3 SGCLAMP protocol, the whole body SGCLAMP 330-360́ was similar to SGMM (1.80 ± 0.82 versus 1.73 ± 0.58 dL/min) and correlated (r = 0.45, p < 0.02). SGCLAMP 210-240́ did not correlate with SGMM (r = 0.24). SIMM and SICLAMP were similar (0.093 ± 0.060 versus 0.087 ± 0.029 dL/min per mU/L) and correlated (r = 0.76, p < 0.001). Conclusions: The time-dependent increase in glucose disposal observed during a prolonged 6-h clamp significantly influences the estimation of SGCLAMP, and significant concordance coefficients are observed between SGMM, and SGCLAMP 330-360́, and SIMM and SICLAMP. © 2010 John Wiley & Sons, Ltd.