Patient and kidney transplant survival in type 1 diabetics after kidney transplant alone compared to simultaneous pancreas‐kidney transplant

BACKGROUND: Donor and other differences mean understanding drivers of transplant survival for type 1 diabetics is challenging. We aimed to compare outcomes of simultaneous pancreas‐kidney transplant over kidney transplant alone for people with end‐stage kidney disease (ESKD) and type 1 diabetes. METHODS: We performed a population‐based cohort study comparing outcomes from kidney alone and kidney‐pancreas transplants using registry data. Our study population was people in Australia and New Zealand with type 1 diabetes and ESKD who received a kidney transplant in 1984–2016. Primary outcomes were time to kidney transplant failure and all‐cause death. Secondary outcomes were time to cardiovascular and non‐cardiovascular death. We compared adjusted survival using Cox regression (hazard ratio HR and 95% confidence intervals CI). RESULTS: Of 1295 type 1 diabetics receiving a transplant, 430 (33%) received deceased donor kidney, 172 (13%) received living donor kidney, and 693 (54%) received pancreas‐kidney transplant. Compared to deceased donor kidney, pancreas‐kidney recipients had 40% lower rate of kidney transplant failure (adjusted HR 0.60; 95% CI 0.45–0.81; p = 0.001) and 34% lower mortality (adjusted HR 0.66; 95% CI 0.53–0.83; p < 0.001), driven by 49% reduction in cardiovascular mortality (adjusted HR 0.51; 95% CI 0.36–0.72; p < 0.001). Pancreas‐kidney recipients had similar reductions in transplant failure and mortality compared to living kidney recipients, after adjusting for transplant timing. CONCLUSIONS: For people with type 1 diabetes, pancreas‐kidney transplant provides improved transplant and overall survival compared to deceased donor kidney alone. Living donor kidneys may perform just as well as pancreas‐kidney transplant if waiting times are short.