Outcomes for Patients With a Deceased Donor Kidney Offer in the New Allocation System

Abstract

Introduction: In the United States (US), disparities in access to kidney transplantation exist for waitlisted candidates with end-stage kidney disease. Meanwhile, changes in kidney allocation policy have been associated with a dramatic increase in the number of organ offers declined before an organ is successfully placed.

Methods: We describe transplant and mortality rates for waitlisted candidates from 2015 to 2022 following these allocation changes.

Results: Among 249,145 incident waitlisted adults, 180,039 received at least 1 offer and were included in the study. Of these, 37.7% received a deceased donor kidney allograft, 14.7% received a living donor allograft, 7.4% died while on the waiting list, 12.7% were removed, and 27.5% were still waitlisted by the study end period. Overall, candidates' median number of days to receiving their first offer declined from 20 (7-48) in 2015 to 5 (2-13) in 2022. Candidates who died while on the waiting list received a median of 25 (9-56) offers and candidates who were removed received a median of 22 (8-53) offers during the study period. The total number of offers generated by the match-run algorithm, including those from nonutilized kidneys, increased sharply from 7,911,688 offers in 2015 to 13,682,914 in 2019, and to 29,332,516 in 2022.

Conclusion: These findings emphasize the inefficiencies inherent in our current allocation algorithms and the need to rethink how waitlisted patients are prioritized for a given deceased donor organ in order to maximize the probability of appropriate utilization of lifesaving organs .

Keywords: access to transplant; kidney allocation.

Graphical abstract

Figure 1

Flow diagram for cohort selection and categorizing waitlist outcomes of incident adult deceased donor kidney transplant candidates in the United States, 2015 to 2022.

Figure 2

Total number of kidneys accepted, and the proportion of kidneys accepted without a decline in the incident adult kidney waitlist population, 2015 to 2022. Multiorgan and multi-listed patients were excluded. Matches that were automatically declined by the allocation system bypasses were also excluded.

Figure 3

Cumulative incidence of deceased donor transplant with competing risks (living donor transplant, waitlist removal, and death) among (a) all candidates and (b) candidates activated on the waitlist after implementation of KAS250.

Figure 4

Center-level differences between the number of offers in 2015 compared with the number of offers in 2022 in the incident adult kidney waitlist population. The red dot indicates the median number of offers among all centers and the diagonal line indicates the line of identity. A close-up of the data is featured on the inset figure.

Figure 5

Number of offers per candidate in the prevalent adult kidney waitlist population, 2015 to 2022. Multiorgan, multi-listed patients, and patients with no offers were excluded. Matches that were automatically declined by the allocation system bypasses were also excluded. The blue line describes the number of offers per candidate among all offers; the orange line describes the number of offers per candidate among only offers resulting in transplant. Of note, neither transplanted nor nonutilized kidneys can be distinguished until all match-run efforts are exhausted.

Figure 6

Total offers per year in the prevalent adult kidney waitlist population for transplanted and nonutilized kidneys, 2015 to 2022. Multiorgan, multi-listed patients, and patients with no offers were excluded. Matches that were automatically declined by the allocation system bypasses were also excluded.