Previous studies have shown an inverse association between pre-transplant dialysis exposure and post-kidney transplant outcomes. Socioeconomic and allocation factors, in contrast to medical factors, play a greater role in dialysis exposure among minorities, and medical causes for delay may impact post-transplant outcomes. This study sought to test whether minorities behaved similarly to Caucasians with regard to the effect of duration of dialysis on post-transplant outcomes. All primary deceased donor kidney transplants between 1997 and 2004 (n = 54,162) were analyzed from the Organ Procurement and Transplant Network database and were categorized as either Caucasian or minority. Adjusted patient and graft survivals were determined in each subgroup based on the duration of pre-transplant dialysis. Caucasians recipients show a clear stepwise increase in risk of graft failure and death with increasing duration of dialysis. The risk of graft failure among minorities increased less without a clear stepwise pattern. The risk of death, however, showed a U-shaped risk profile with the highest risk of death among preemptive transplants and recipients with more than five yr of dialysis. The disparate effect of dialysis on minorities suggests that a selection bias and not a biologic effect may explain the association between dialysis duration and outcomes after kidney transplantation previously reported.
© 2011 John Wiley & Sons A/S.