Restored insulin secretion and euglycemia in type 1 diabetes a decade and more after successful pancreas transplantation

Although successful pancreas transplantation has been demonstrated to be efficacious in restoring endogenous insulin secretion and normal blood glucose levels, it remains a highly controversial form of therapy for type 1 diabetes. A major obstacle to acceptance of this procedure is the lack of proven long-term success. We performed these studies to assess the hypothesis that successful pancreas transplantation is efficacious in long-term (over a decade) normalization of endogenous insulin secretion and glycemia. 16 patients with histories of diabetic complications who had been transplanted with either a whole or a segment of pancreas 10 to 18 years earlier were studied. All patients were taking immunosuppressive drugs but none was using insulin or other hypoglycemic agents. All recipients had normal levels of fasting blood glucose (91 ± 3 mg/dl) and HbA1c (5.15%) and 15/16 stated their qualities of life had improved after transplantation. They had intact acute insulin responses to intravenous pulses of glucose (73 ± 24 μU/ml) and to arginine and (47 ± 11 μU/ml) substantial insulin secretory reserve 187 ± 45 μU/ml. Glucose-potentiation of arginine-induced insulin secretion (GPAIS), the measure of insulin secretory reserve, correlated significantly (r = 0.95, p< 0.001) with the acute insulin response to intravenous glucose (AlRg), rendering the latter a much simpler and valid measure of functional beta cell mass. While pancreas transplantation cannot be considered as treatment for all diabetic patients, it should be seriously considered for use in patients with a deteriorating clinical course whose response to pharmacologic treatment is inadequate.