Comparison of Clinical Outcomes Between Preemptive Transplant and Transplant After a Short Period of Dialysis in Living-Donor Kidney Transplantation: A Propensity-Score-Based Analysis

BACKGROUND: The permissible extent of pretransplant dialysis for patient and allograft survival is unclear. We assumed that a short period of dialysis before living donor kidney transplantation (LDKT) will show the similar results as preemptive kidney transplantation (PKT). MATERIAL/METHODS: We retrospectively evaluated the outcomes of LDKT according to pretransplant dialysis duration in both unmatched cohorts (n=1984) and propensity-score-matched cohorts (n=986) cohorts. The primary study endpoint was post-transplantation patient survival and death-censored graft survival (DCGS) according to the duration of pretransplant dialysis by 19 months which was the best cutoff value to differentiate clinical outcomes with the use of the time-dependent area under the curve. RESULTS: Of 1984 patients with LDKT at our center between January 2005 and September 2016, PKT was performed in 429 patients. The durations of pretransplant dialysis were <19 months in 962 recipients and ≥19 months in 593 recipients. There was no significant difference in mortality and DCGS between PKT and non-PKT recipients with pretransplant dialysis of <19 months. Patient survival (P=0.024) and DCGS (P=0.001) were worse in non-PKT recipients with pretransplant dialysis of ≥19 months. In the matched cohort, DCGS was significantly lower in non-PKT recipients with pretransplant dialysis of ≥19 months (P=0.037). It is likely that the incidence of biopsy-proven acute rejection was higher in this group (P=0.083). CONCLUSIONS: Patient survival and DCGS were worse when the pretransplant dialysis duration was ≥19 months in a propensity-score-matched LDKT cohort.