Short Pretransplant Dialysis Periods are Clinically Acceptable Without Compromising Kidney Transplant Outcomes: A Japanese Multicenter Study.

OBJECTIVES: Preemptive kidney transplantation (PEKT) is known to have better outcomes than kidney transplantation (KT) after dialysis therapy. However, the effect of pretransplant dialysis duration (PTDD) on KT outcomes under good hemodialysis control remains unclear. We investigated the association between PTDD and KT outcomes in a Japanese cohort with favorable dialysis management. METHODS: Among three institutions, 805 patients who underwent a living donor KT between 2001 and 2021 were enrolled in this study. Those who underwent more than one KT, multiple organ transplantations in addition to KT, or transplantations at < 20 years of age were excluded. Calcineurin inhibitors, mycophenolate mofetil, and steroids were the primary maintenance immunosuppressors. RESULTS: The allograft survival rates of the non-PEKT group were significantly lower than those of the PEKT group (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.04-2.70). Univariate analysis showed that ≥ 2 years of PTDD demonstrated the highest HR for allograft loss when PTDD was separated by year (95% CI 1.11-2.55). Multivariate analysis showed that ≥ 2 years of PTDD (HR 2.61 [95% CI 1.58-4.38]), being a male recipient (HR 2.35 [95% CI 1.30-4.53]), and having diabetic nephropathy (HR 2.94 [95% CI 1.71-4.98]) were suggested to be risk factors for allograft loss. Additionally, < 2 years of PTDD resulted in significantly higher allograft survival rates; the 10-year allograft survival rates of recipients with ≥ 2 years and < 2 years of PTDD were 82.0% and 91.8%, respectively. CONCLUSIONS: Allograft survival remained unaffected when KT is performed after a short-term dialysis introduction.