Impact of prolonged dialysis prior to renal transplantation

IntroductionThe new kidney allocation system (KAS) prioritizes patients based on date of dialysis initiation or waitlisting, whichever is earlier. We hypothesized that this change would increase transplant rates for patients with prolonged pretransplant dialysis times (DT) and aimed to assess the impact of prolonged DT on post-transplant outcomes. MethodsWe used United Network for Organ Sharing registry data to assess outcomes for patients added to the renal transplant waitlist from January 1, 1998 to December 31, 2010 and patients transplanted from January 1, 1998 to December 3, 2012. ResultsCompared with patients transplanted pre-emptively, patients with <5years, 5-9years, and 10years DT had progressively decreased graft and patient survival (P<.001). The rates of short-term complications including delayed graft function, graft loss within 30days, and patient death within 30days were significantly higher in cohorts with 10years DT than in cohorts with less DT (P<.001). ConclusionsPatients with pretransplant DT of 10years had worse outcomes than patients pre-emptively transplanted or transplanted with shorter DT. Durations of dialysis dependence beyond 10years were associated with further deterioration in short-term but not long-term post-transplant outcomes.