Clinical Results after Islet Transplantation

After the discovery of insulin,1it was believed that diabetes was cured; however, the chronic complications of diabetes soon became evident. For the patient with Type 1 diabetes, the fine control of hyperglycemia to prevent retinopathy, nephropathy, neuropathy, or vascular disease has to be offset against the risk of hypoglycemia. The Diabetes Control and Complications Trial of the National Institute of Diabetes and Digestive and Kidney Diseases has unequivocally confirmed that hyperglycemia is associated with progressive complications, yet at the same time intensive insulin therapy has been associated with a three-fold increased risk of hypoglycemia.2These observations provide the stimulus for the development of alternative means of therapy. Although insulin analogues will undoubtedly facilitate this, to date they have not been associated with euglycemia. Pancreas transplantation alone has been associated with normoglycemia, but it is a major surgical procedure that is associated with significant morbidity, some mortality, and a one-year graft survival rate of about 86%.3,4Islet transplantation, on the other hand, is a simple procedure, but it has been associated with poor long-term success; at best, 10% of recipients have insulin independence at one year.5Last year we published preliminary results that confirmed that islet transplantation can be successful in establishing insulin independence,6and now we provide an update of these results as fully detailed in our recent report.7 Patients with Type 1 diabetes were selected for these studies. All had confirmed C-peptide absence and were selected on the basis of labile glucose values, as confirmed by a mean amplitude of glycemic excursion8of greater than 11.1 mmol/L, or by recurrent hypoglycemia, particularly if it is associated with decreased patient-awareness of hypoglycemia. In addition to labile glucose values, patients typically demonstrated disruption of their daily lives by diabetes. All patients must have …