The effect of long-term glibenclamide treatment on glucose tolerance, insulin secretion and serum lipids in subjects with impaired glucose tolerance.

The effects of glibenclamide plus diet (n = 27) or diet alone (n = 18) on glucose tolerance, insulin secretion and serum lipids in non-obese subjects with normal or low insulin responses and impaired glucose tolerance (IGT) has been followed up for two years. Glucose tolerance and insulin secretion were characterized by means of a glucose infusion test consisting of an initial injection of 0.33 g glucose/kg body weight followed by 12 mg/kg body weight/min for 2 h. Dietary treatment did not improve glucose tolerance in normal and low insulin-responders. Glibenclamide plus diet succeeded in improving glucose tolerance only in low insulin responders whereas glucose tolerance remained unchanged in normal insulin responders. There was a significant decrease in fasting and glucose-stimulated insulin levels after two years of glibenclamide treatment in both the normal and low insulin-responders. The body weight was not altered. Triglyceride and cholesterol levels both decreased. In summary, the present study failed to demonstrate an increase in insulin secretion under chronic administration of glibenclamide in subjects with IGT independent of the type of insulin response. From the practical point of view, glibenclamide is of benefit in the treatment of non-obese subjects with IGT and relative insulin deficiency.