Fasting Blood Sample–Based Assessment of Insulin Sensitivity in Kidney-Pancreas– Transplanted Patients

OBJECTIVE — To ascertain whether simple indexes of insulin sensitivity based on a fasting blood sample may be reliable measures of insulin sensitivity in combined kidney-pancreas– transplanted patients. RESEARCH DESIGN AND METHODS — Estimates of insulin sensitivity based on fasting plasma glucose, insulin (homeostasis model assessment of insulin sensitivity [HOMA-IS], Quantitative Insulin Sensitivity Check Index [QUICKI]), and free fatty acid (revised QUICKI) concentrations were compared with insulin sensitivity as assessed with the gold standard tech-nique (euglycemic-hyperinsulinemic clamp) in 22 patients who had undergone kidney-pancreas transplantation (KP-Tx) and 18 matched healthy subjects (NOR). RESULTS — In KP-Tx patients, indexes based on the glucose-insulin product, HOMA-IS (r 0.47, P 0.03) and QUICKI (r 0.47, P 0.03), were shown to be reliable measures of insulin sensitivity. The introduction of fasting plasma free fatty acid concentration in the revised QUICKI (r 0.76, P 0.0001) considerably improved the power of prediction of the clamp-based measure of insulin sensitivity as observed in the healthy control subjects (r 0.83, P 0.0001)