Contemporary Prevalence and Practice Patterns of Out-of-Sequence Kidney Allocation.

Since 2021, the OPTN has reported a nearly 10-fold rise in out-of-sequence (OOS) kidney allocation, generating concern and halting development of continuous distribution policies. We report contemporary (2022-2023) practice patterns in OOS allocation using OPTN data. We examined in sequence vs. OOS donors with multivariable logistic regression and skipped vs. OOS-accepting recipients with conditional logistic regression. Nearly 20% of kidney placements were OOS, varying from 0% to 43% across OPOs; the 5 highest-OOS OPOs accounted for 29% of all OOS. Of OOS kidneys, 33% were declined >100 times in the standard allocation sequence and 51% were declined by >10 centers before OOS allocation began; 4.5% were made without any in-sequence declines. Nearly all OOS offers were open offers. OOS kidneys were more likely to be from female, Black, older, DCD, hypertensive, diabetic, and elevated creatinine donors. Candidates receiving OOS kidneys were more likely female, Asian, and older than skipped candidates. Higher-volume centers and centers with more White, fewer Hispanic, and more educated waiting list patients transplanted disproportionately more OOS kidneys. These findings suggest that the current, highly variable, discretionary use of OOS might exacerbate disparities, yet the impact of OOS on organ utilization cannot be determined with data now collected.