Background: The advantage of preemptive kidney transplantation (KT) is well established, but the association of dialysis vintage with allograft survival is less clear. We evaluated the prognosis of KT recipients according to pretransplant dialysis vintage.
Methods: We retrospectively evaluated 1,843 first KT recipients transplanted between 2006 to 2021 at Seoul St. Mary’s Hospital. Duration of dialysis was used as a categorical variable divided by tertiles according to distribution of time of analysis, and preemptive transplantation was categorized as a separate group. Primary outcomes were death-censored graft loss and all-cause mortality and composite outcomes.
Results: Preemptive KT was received by 369 patients, with average pretransplant dialysis periods of 1.2 months, 21.4 months, and 107.6 months for each tertile, which included 491 patients, respectively. Mean duration of follow-up was 87 months, during which 88 (4.8%) deaths and 232 (12.6%) graft losses occurred. There were no significant differences in overall survival for the first or second tertile compared to preemptive KT group. However, the third tertile showed a significantly higher all-cause mortality (adjusted hazard ratio, 3.156; 95% confidence interval, 1.476–6.750; P=0.003). Although the rate of graft failure was highest in the third tertile, there were no statistically significant differences in death-censored graft loss or the composite outcome.
Conclusions: A longer period of pretransplant dialysis was associated with a higher risk of all-cause mortality. However, the association between longer dialysis vintage and increased risk of graft failure was unclear.