Transplantation of Patients With Long Dialysis Vintage in the Current Deceased Donor Kidney Allocation System (KAS).

ABSTRACT

RATIONALE & OBJECTIVE: In 2014 the wait-time calculation for deceased donor kidney transplantation in the United States was changed from the date of first waitlisting to the date of first maintenance dialysis treatment with the aim of minimizing disparities in access to transplantation. This study examined the impact of this policy on access to transplantation, patient survival, and transplant outcomes among patients treated with maintenance dialysis for a prolonged duration before waitlisting. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Patients identified in the US Renal Data System between 2008 and 2018 aged 18-70 years and in the 95th percentile of dialysis treatment duration (≥6.5 years) before waitlisting. EXPOSURE Waitlisting for transplantation before versus after implementation of the policy. OUTCOME: Time from date of waitlisting to deceased donor transplantation and death, and from date of transplantation to all cause graft loss. ANALYTICAL APPROACH: Univariate and multivariable time to event analyses. RESULTS: Patients waitlisted after the policy change had a higher likelihood of deceased donor transplantation (HR, 3.12 [95% CI, 2.90-3.37]) and lower risk of death (HR, 0.74 [95% CI, 0.63-0.87]). The risk of graft loss was lower in the post-kidney allocation system (KAS) cohort (HR, 0.66 [95% CI, 0.55-0.80]). The proportion of adult patients treated with dialysis ≥6.5 years who were never waitlisted for transplantation remained high (73%) and did not decrease after the policy implementation. LIMITATIONS: Cannot determine causality in this observational study. CONCLUSIONS: The policy change was associated with an increase in deceased donor transplantation and marked improvement in patient survival for patients waitlisted after long periods of dialysis treatment without decreasing the utility of available deceased donor kidney supply. The policy was not associated with increased waitlisting of this disadvantaged population.