Being Waitlisted is not Enough-Identification of Pseudo-access to Kidney Transplantation in the United States.

Objective: We sought to determine how kidney transplant center volume impacts waitlisted candidate access to transplant.

Summary Background Data: Over 90,000 candidates await a kidney transplant, of which we hypothesized that waitlist access is subject to significant program-level variation, potentially resulting in pseudo-access: a state where the waitlisted candidate does not achieve expected transplantation.

Methods: Center-level data on all U.S. adult kidney transplant programs was collected using the Scientific Registry of Transplant Recipients program-specific reports, updated through 12/31/23. Programs (N=196) were stratified into quartiles by yearly deceased donor kidney transplant volume (Q1 lowest, Q4 highest); program acceptance practices and outcomes were compared.

Results: Compared to lower volume programs, Q4 programs transplanted a higher proportion of their waitlist (30.5% vs 13.1% for Q1;P<0.001) with a higher transplant rate ratio (1.41 vs 0.74 for Q1;P<0.001), and an accelerated time to transplant (median time to transplant ratio: 0.79 vs 1.2 for Q1;P=0.008). Offer acceptance ratios were significantly higher at Q4 programs, particularly for marginal allografts (KDRI>1.75: 1.51 vs 0.46 for Q1;P<0.001) and hard-to-place kidneys (>100 offers: 1.18 vs 0.25 for Q1;P<0.001). Despite increased utilization of more marginal grafts, Q4 programs demonstrated shorter post-transplant hospital lengths of stay (median 4 days [4-5] vs 6 [5-7] for Q1; P<0.001).

Conclusion: High-volume (HV) programs excel through aggressive organ utilization, while low-volume (LV) programs often provide pseudo-access to transplantation, characterized by low transplant rate ratios, conservative offer acceptance practices, and prolonged wait times. To increase kidney allograft utilization, LV programs unable to improve acceptance practices should consider consolidation or the development of access programs to facilitate candidate migration to HV centers.