Kidney Transplant Wait Times Under Waiting List Expansion Scenarios.

Abstract

Importance: Kidney transplantation offers survival benefits and superior quality of life compared with maintenance dialysis for patients with end-stage kidney disease (ESKD), but it is limited to approximately 25 000 patients annually in the United States. Expanding access to transplant could be accomplished by allowing more patients to join the waiting list or by increasing organ supply.

Objective: To estimate how these interventions could affect transplant wait times.

Design, setting, and participants: This decision-analytic study used a Markov model with a simulated cohort of transplant-eligible US patients over 10 years (2022-2032).

Exposures: Three expansion strategies: waiting list expansion alone, waiting list expansion with deceased-donor transplant (DDT) expansion, and waiting list expansion with living-donor transplant (LDT) expansion. Relative 10%, 25%, 50%, and 100% expansions of the current deceased-donor organ supply and 25%, 50%, 100%, and 200% expansions of current living donation rates were simulated, modeling 2 degrees of waiting list expansion (10% and 50%) for each strategy.

Main outcomes and measures: Median wait time to kidney transplant using Kaplan-Meier survival analysis.

Results: There were a total of 662 190 transplant-eligible patients in the simulated cohort, with a mean (SD) age of 58.7 (14.7) years; 327 126 (49%) female individuals; and 269 082 (41%) Black, 163 028 (25%) Hispanic, 233 739 (35%) non-Hispanic White, and 78 496 (12%) Asian individuals and individuals with another race or ethnicity. Under the baseline strategy, median (IQR) wait time was 32.8 (13.1-66.4) months and increased to 36.8 (14.7-74.7) months and 52.6 (21.0-107.9) months for 10% and 50% waiting list expansion alone. DDT and LDT expansion strategies added 1911 to 20 035 organs. For 10% waiting list expansion, median (IQR) wait times ranged from 23.7 (9.3-47.8) months to 34.5 (13.9-74.7) months. For 50% waiting list expansion, median (IQR) wait times ranged from 34.2 (13.6-69.4) months to 49.4 (19.7-101.0) months.

Conclusions and relevance: In this decision-analytic model, expansion strategies without additional organ supply increased the median time to kidney transplant by nearly 2 years; 10% waiting list expansion required at least 2850 additional organs to shorten wait times. However, 50% waiting list expansion required at least 11 000 additional organs to approximate current wait times. Reduction in the deceased-donor organ nonuse rate alone is unlikely to meet the shortfall. Systems-level efforts to significantly increase deceased and living donation should be prioritized alongside increased access to the transplant waiting list.