Comparison of insulin sensitivity, glucose sensitivity, and first phase insulin secretion in patients treated with repaglinide or gliclazide.

The traditional sulfonylureas with long half-lives have sustained stimulatory effects on insulin secretion compared to the short-acting insulin secretagogue. In this study, we used the frequently sampled intravenous glucose tolerance test (FSIGT) to evaluate the insulin sensitivity (IS), glucose sensitivity (SG), and acute insulin response after glucose load (AIRg) after 4 months treatment with either gliclazide or repaglinide. The design of study was randomizedcrossover. We enrolled 20 patients with new-onset type 2 diabetes (mean age, 49.3 years). Totally three FSIGTs were performed, one before and one after each of the two treatment periods as aforementioned. No significant differences in fasting plasma glucose, insulin, body mass index, blood pressure, glycated hemoglobin, or lipids were noted between the two treatments. After the repaglinide treatment, higher AIRg, lower IS, and lower SG were noted, but they did not reach statistical significance. The disposal index (DI) was also not significantly different between the two treatments. In conclusion, since non-significantly higher DI, AIRg, lower IS and SG were noted after repaglinide treatment, it might be a better treatment for diabetes, relative to gliclazide.