The impact of pancreas transplantation on kidney allograft survival

Whether pancreas after kidney transplantation (PAK) compromises kidney allograft survival, and what pre-PAK glomerular filtration rate (GFR) should be used to select patients for PAK is unclear. We analyzed all (n = 2776) PAK recipients in the United States between 1989 and 2007 and compared their risk of kidney failure to a comparator group of n = 13 635 young adult diabetic kidney only transplant recipients during the same time after accounting for selection bias by the use of a propensity score for PAK in a multivariate time to event analysis. In a secondary analysis, we determined the association of pre-PAK GFR with subsequent kidney allograft survival. Despite an increased risk of death early after pancreas transplantation, PAK recipients had a decreased long-term risk of kidney allograft failure compared to diabetic kidney only transplant recipients HR = 0.89; 95% CI: [0.78-1.00]; p = 0.05. An association of pre-PAK GFR with kidney survival was not evident until 3 years after pancreas transplantation, and patients with a pre-PAK GFR of 30-39 mL/min still attained 10-year post-PAK kidney survival of 69%. We conclude that PAK is associated with improved kidney allograft survival, and pre-PAK GFR 30-39 mL/min should not preclude PAK. Expanded use of PAK is warranted. Data taken from the UNOS and USRDS registries demonstrate that despite an increased risk of kidney allograft failure immediately after pancreas transplantation, pancreas after kidney transplantation is associated with a long-term kidney allograft survival advantage.