Impact of delayed graft function and acute rejection on kidney graft survival

1. From 1991 to 1998, the incidence of DGF remained at 21% of all kidney grafts (n = 86,682) reported to the UNOS Scientific Transplant Registry. In contrast, percentages of early acute rejection (EAR) and late acute rejection (LAR) have dropped precipitously to half their starting values. (EAR started at 37% and dropped to 18%, and LAR started at 11% and dropped to 5%.) 2. Among discharged recipients, DGF was associated with increased EAR (odds ratio = 1.7) within 6 months of transplant; whereas, EAR (odds ratio = 4.7) but not DGF (odds ratio = 1.1) was associated with increased LAR for recipients from 6 months to one year after transplantation. 3. Non-immune factors (e.g., duration of pretransplant dialysis, donor age, and cold ischemia time) primarily influenced the risk of DGF, and immune factors (e.g., recipient race, recipient age, HLA) mainly determined the risk of EAR and LAR. 4. DGF, EAR and LAR were independent risk factors for long-term graft loss. DGF and LAR exhibited the strongest influences, reducing half-lives by 30% and 50%, respectively. 5. Some long-term risk factors demonstrated consistent effects regardless of DGF and/or LAR. For example, Black recipients always had poor long-term GS. On the other hand, some risk factors, mostly immune-type factors, exhibited effects only in the absence of DGF (e.g., recipient sex, age and HLA matching). Many non-immune factors exhibited long-term effects only in the absence of LAR (e.g., donor age, cause of donor death). 6. Strategies aimed at reducing both DGF and AR are necessary to improve the long-term outcome of kidney transplants.