Treating Type 1 Diabetes by Pancreas Transplant Alone: a Cohort Study on Actual Long-Term (10 Years) Efficacy and Safety

Background: Physiologically regulated insulin secretion and euglycemia are achievable in type 1 diabetes (T1D) by islet or pancreas transplantation. However, pancreas transplant alone (PTA) remains a debated approach, with uncertainties on its relative benefits and risks. We determined the actual long-term (10 years) efficacy and safety of PTA in carefully characterized T1D subjects. Methods: This is a single-centre, cohort study in 66 consecutive T1D subjects who received a PTA between April 2001 and December 2007, and were then all followed until 10 years since transplant. Main features evaluated were patient survival, pancreas graft function, C-peptide levels, glycemic parameters, and the function of the native kidneys. Results: Ten-year actual patient survival was 92.4%. Optimal (insulin-independence) or good (minimal insulin requirement) graft function was observed in 57.4 and 3.2% of patients, respectively. Six (9.0%) patients developed stage 5 or 4 chronic kidney disease. In the remaining individuals bearing a successful PTA, eGFR decline per year was -2.29±2.69 ml/min/1.73m. Reduction of eGFR at 1 year post-PTA was higher in those with pre-PTA hyperfiltration and higher HbA1c concentrations; eGFR changes afterwards significantly correlated with diabetes duration. In recipients with normoglycemia at 10 years, 74% of normo- or micro-albuminuric subjects pre-PTA remained stable, and 26% progressed towards a worse stage; conversely, in 62.5% of the macro-albuminuric individuals albuminuria severity regressed. Conclusions: These long-term effects of PTA on patient survival, graft function and the native kidneys support PTA as a suitable approach to treat diabetes in selected T1D patients.