Background: The use of kidneys from expanded-criteria donors (ECD) is regarded with caution.
Methods: We compared 279 kidney transplant recipients (KTxR) from standard-criteria donors (SCD) and 237 from ECD, transplanted between January 1990 and December 2006. We evaluated the impact of immediate graft function (IGF), slow graft function (SGF), and delayed graft function (DGF) and the drop in estimated glomerular filtration rate (ΔeGFR) ≤ 30% or > 30% during the first year after transplantation on long-term patient and death-censored graft survival (DCGS).
Results: Ten-year patient survival was similar in SCD- or ECD-KTxR (P = 0.38). DCGS was better in SCD-KTxR versus ECD-KTxR (77.3% vs. 67.3%; P = 0.01). DCGS did not differ in either group experiencing IGF (P = 0.17) or DGF (P = 0.12). However, DCGS was worse in ECD-KTxR experiencing SGF (84.9% vs. 73.7%; P = 0.04). Predictors of DCGS were 1-year serum creatinine (hazard ratio, 1.03; P < 0.0001) and ΔeGFR > 30% between 1 and 12 months (Δ1-12eGFR) after transplantation (hazard ratio, 2.2; P = 0.02). In ECD-KTxR with IGF and more than 1-year follow-up, 10-year DCGS was better in those with Δ1-12eGFR ≤ 30% versus those with Δ1-12eGFR > 30% (83.8% vs. 53.6%; P = 0.01).
Conclusion: Recipients of SCD or ECD kidneys with IGF or DGF had similar 10-year patient survival and DCGS. SGF had a worse impact on DCGS in ECD-KTxR. In addition to 1-year serum creatinine, Δ1-12eGFR > 30% is a negative predictor of DCGS. Larger studies should confirm if increasing the use of ECD, avoiding factors that contribute to SGF or DGF, and/or a decline in eGFR during the first year after transplantation may expand the donor pool and result in acceptable long-term outcomes.