Impact of Acuity Circles on Outcomes for Pediatric Liver Transplant Candidates.

BACKGROUND: In December 2018, UNOS approved an allocation scheme based on recipients' geographic distance from a deceased donor ("acuity circles"). Previous analyses suggested acuity circles (AC) would reduce waitlist mortality overall, but their impact on pediatric subgroups was not considered. METHODS: We applied Scientific Registry of Transplant Recipients data from 2011-2016 towards the Liver Simulated Allocation Model (LSAM) to compare outcomes by age and illness severity for the UNOS-approved AC and the existing Donor Service Area (DSA)/Region-based allocation schemes. Means from each allocation scheme were compared using matched-pairs t-tests. RESULTS: Over a 3-year period, AC allocation is projected to decrease waitlist deaths in infants (39 vs 55; P<0.001), children (32 vs 50; P<0.001), and teenagers (15 vs 25; P<0.001). AC allocation would increase the number of transplants in infants (707 vs 560; P<0.001), children (677 vs 547; P<0.001), and teenagers (404 vs 248; P<0.001). AC allocation led to decreased median PELD/MELD at transplant for infants (29 vs 30; P=0.01), children (26 vs 29; P<0.001), and teenagers (26 vs 31; P<0.001). Additionally, AC allocation would lead to fewer transplants in status 1B in children (97 vs 103; P=0.006) but not infants or teenagers. With AC allocation, 77% of pediatric donor organs would be allocated to pediatric candidates, compared to only 46% in DSA/Region-based allocation (P<0.001). CONCLUSION: AC allocation will likely address disparities for pediatric liver transplant candidates and recipients by increasing transplants and decreasing waitlist mortality. It is more consistent with federally-mandated requirements for organ allocation.