Out-of-Sequence Placement of Deceased Donor Kidneys is Exacerbating Inequities in the United States

Background: Deceased donor kidney allocation in the United States follows an objective algorithm that is designed to balance equity and utility. Organ procurement organizations (OPOs) are increasingly using out-of-sequence allocation of deceased donor kidneys (DDKs) to improve organ utilization rates. We investigated trends in the prevalence of out-of-sequence allocation in DDKs, and the association with successful organ placement, and its impact on equity and organ utilization. Methods: Using 2020-2023 transplant data from the Scientific Registry of Transplant Recipients and organ offer data from the potential transplant recipient dataset, we identified all organ offers for DDKs, including those placed out-of-sequence, along with donor and recipient characteristics. We obtained the prevalence of out-of-sequence allocation and placement in DDKs and assessed temporal trends across organ quality as measured by the kidney donor profile index (KDPI). Lorenz curves and Gini coefficients measured inequality for out-of-sequence transplantation at the transplant center and OPO levels. Results: From 2020 to 2023, out-of-sequence placement of DDKs increased from 328 kidneys in 2020 (2%) to 3,470 in 2023 (18%). Out-of-sequence placements now account for one in six DDK transplants and include kidneys across the organ quality spectrum, with 40% of these occurring with KDPI<50% (i.e., the highest quality) kidneys. By 2023, all 55 OPOs were using out-of-sequence allocation, reflected in the Gini coefficient decreasing from 0.88 to 0.43 with no appreciable impact on utilization rates. Conclusions: There has been a sharp increase in out-of-sequence allocation of DDKs including high-quality organs. Most of these kidneys are being placed at a small number of transplant centers, creating preferential access to transplantation and exacerbating inequities in access to transplantation.