Despite several therapeutic options existing for the patients with type I diabetes, the patients are still at high risk for severe acute and chronic complications (1). Pancreatic islet transplantation is a promising therapy to achieve good glycemic control with no or little additional insulin (2). This study was to evaluate the effectiveness, safety, economics and social ethics of islet transplantation (IT) for the patients with type I diabetes.

We searched PubMed, Cochrane Library, CNKI and CBM to retrieve eligible literatures. The values of H1bAc before and after transplantation, the rates of insulin independence and functional islet graft at the last follow-up, and the insulin dose per patient-day were analyzed. Descriptive statistics, t tests and random effects meta-analyses were used in the study.

Totally 21 original papers with 488 cases from 9 different countries were reviewed and analyzed. The studies showed that the H1bAc was decreased from 7.7 percent (95 percent Confidence Interval, CI: 7.4, 8.1) before IT to 6.2 percent (95 percent CI: 5.9, 6.4) after IT. At the last follow-up, the rate of insulin independence was 48.96 percent (95 percent CI: 31.32, 66.73) and the rate of functional islet graft was 65.79 percent (95 percent CI: 47.06, 82.21). The daily insulin requirement dropped from 0.52U/kg/d to 0.21 U/kg/d. The main adverse events of islet transplantation were bleeding (7.01 percent) and the complications related to immunosuppression therapy (6.37 percent), but they were less than those of whole pancreas transplantation.

Another study with a 20-year follow-up also showed that the cost-effectiveness of islet transplantation (USD47,800 per QALY) was better than that of insulin therapy (USD71,000 per QALY). In spite of the better evidences of islet transplantation, the insufficient organ donation and issues of cell purification and immunological rejection limited islet transplantation's widespread utilization (1).

The islet transplantation therapy for the patients with type I diabetes has a potential to achieve insulin independence and better cost-effectiveness, and is relatively safe. But there are some obstacles for its wide utilization.