Determinants of Long Waiting Time to Kidney Transplantation

Background: Disparity in waiting time to kidney transplantation led to new policy (KAS250). Our aims were to identify variables associated with long wait time (LWT); assess the impact of KAS250 on WT; and analyze modifiable transplant center behaviors correlated with WT.

Methods: SRTR data for adult deceased donor kidney transplants were analyzed. Time-periods from 8/1/2018-7/31/2019 and 5/1/2021-4/30/2022 were chosen for pre- and post-KAS250 analyses. Transplant centers were categorized as LWT or SWT centers depending on whether pre-KAS250 median center waiting times were greater or less than the national pre-KAS250 median waiting time of 57.8 months.

Results: In multivariate analysis, transplantation with HCV NAT negative kidneys was associated with an additional 21.3 months of WT (CI: 18.5-24.2, P < .0001), and transplantation with KDPI <85% kidneys was associated with an additional 10.8 months (CI: 8.2-13.3, P < .0001). Post-KAS250 national kidney transplant waiting time decreased from 61-58 months (P < .0001) and waiting time at LWT centers decreased from 74-69 months (P < .0001). Cold ischemic times (CIT) increased (20.2 hours vs 18.3 hours, P < .0001) and DGF rates also increased (32.7% vs 31.0%, P < .0001). Centers generally displayed more aggressive transplantation practices post-KAS250 however significant differences in DCD utilization, organ offer acceptance ratios and tolerance for long CIT persist between SWT and LWT centers.

Conclusion: KAS250 has reduced waiting time disparities between SWT and LWT centers at the cost of increased CIT and DGF and reduced allocation efficiency. Significant differences in transplant practice persist between SWT and LWT centers.