Effects of acute starvation on insulin resistance in obese patients with and without type 2 diabetes mellitus

Background Et Aims: Starvation decreases insulin sensitivity and glucose tolerance in both lean and obese (013) non-diabetic subjects. Influence of drastic calorie reduction on insulin resistance in patient with type 2 diabetes (T2DM) is not known. Methods: We enrolled 10 T2DM (diabetes duration 11.1 +/- 7.9 years) and 10 OB age and weight-matched subjects and performed isoglycaemic hyperinsulinaemic clamp (two 120min phases of 60 and 120 mlU min(-1) m(-2) i.v. insulin) with indirect calorimetry at baseline and after 60h of fasting. Results: After starvation insulin-mediated glucose disposal decreased significantly in both hyperinsulinaemic phases in T2DM (phase 1: from 46 +/- 28 to 33 +/- 17, P < 0.004; phase 2 from 122 +/- 47 to 80 +/- 30 mu g kg(-1) min(-1), P < 0.01) as well as in OB (phase 1: from 94 +/- 52 to 52 +/- 24, P < 0.04; phase 2: from 131 +/- 46 to 106 +/- 43 mu g kg(-1) min, P < 0.01). Both oxidative and non-oxidative components of glucose disposal tended to be reduced after fasting. A change of insulin sensitivity was found to be highly dependent upon pre-starvation conditions: more insulin resistant subjects tended to maintain (or modestly improve) insulin resistance whilst subjects with better insulin sensitivity tended to worse it. Conclusion: Insulin sensitivity worsens similarly in both T2DM and OB subjects during 60-h fast. The change is probably predictable according to pre-starvation insulin sensitivity. (c) 2005 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.