Treatment of patients with non-insulin-dependent diabetes mellitus: diabetic control and insulin secretion and action after different treatment modalities.

In order to define the relationship between treatment-induced changes in diabetic control and improvement in in vivo insulin-stimulated glucose utilization (insulin clamp technique) 30 patients with non-insulin-dependent diabetes mellitus (NIDDM) were treated with either insulin, glipizide or diet alone, depending on their initial weight. Fasting plasma glucose concentrations fell from 16.3 +/- 1.2, 15.9 +/- 1.0, and 16.3 +/- 1.0 mmol/l, (mean +/- SE) to 6.3 +/- 0.5, 11.6 +/- 0.6, and 13.4 +/- 1.6 mmol/l, after insulin, glipizide and weight reduction, respectively. These changes in fasting plasma glucose concentration were associated with an improvement in insulin-stimulated glucose uptake, which increased by 69% after insulin, 45% after glipizide, and 72% after weight reduction. Thus, the improvement in insulin action was comparable in the three different groups of patients following each therapeutic intervention, and appeared to be unrelated to the fall in plasma glucose concentration. These results appear to suggest that the ability of any specific treatment to improve diabetic control can vary independently of its effect on in vivo insulin-stimulated glucose utilization.