Restoration of sensitivity to sulfonylurea after strict glycaemic control with insulin in non-obese type 2 diabetic subjects.

Ten non-obese type 2 diabetic patients with secondary failure to sulfonylureas received an intensive insulin therapy (four doses schedule) for 90 days. The glycaemic control was poor at entry (HbA1c = 11.7 +/- 1.2%) and ameliorated significantly after insulin (HbA1c = 7.1 +/- 0.7%, p less than 0.01). The reintroduction of the sulfonylurea after insulin withdrawal resulted in a persistent satisfactory long-term control (300 days) in all, but two diabetics responded no more after about 3 and 4 months of clinical remission (good control on sulfonylurea). Both basal and stimulated (iv glucagon and mixed meal) beta-cell secretory activity increased significantly at 3 months and declined thereafter without falling below baseline values. Three months of strict metabolic control seem to restore the sensitivity to sulfonylurea by enhancing beta-cell secretory activity in non-obese type 2 diabetic patients.