Regional Variation in Early Effects of Acuity Circle-Based Liver Allocation
Recommended Citation
Ivanics T, Nagai S, Kitajima T, Shimada S, Shamaa TM, Collins K, Rizzari M, Yoshida A, Moonka D, Abouljoud M. Regional Variation in Early Effects of Acuity Circle-Based Liver Allocation. Am J Transplant 2022; 22:473.
Document Type
Conference Proceeding
Publication Date
6-1-2022
Publication Title
Am J Transplant
Abstract
Purpose: Liver allocation in the United States was updated on February 4th, 2020, byintroducing the acuity circle (AC)-based model. This study evaluated the early effects of the AC- based allocation on waitlist outcomes. Methods: Adult liver transplant (LT) candidates without MELD exception listed between Jan-1-2019 and Sep-30-2021 were assessed. Two periods were defined according to the LT listing date(pre- and post-AC), and 90-day waitlist outcomes were compared. Data was censored if none ofthe waitlist events had occurred before the end of the period. The median transplant MELD scoreof each transplant center was calculated, with centers categorized as low- (<25%ile), mid- (25-75%ile), and high-MELD (>75%ile) centers. Results: A total of 11,364 and 15,900 LT candidates in the pre- and post-AC eras wereidentified. Overall, the post-AC era was associated with a higher cause-specific hazard (csHR) of90-day waitlist mortality (csHR=1.21,95%CI=1.09-1.34;P<0.001) and a higher cause-specifichazard of transplant (csHR=1.37,95%CI=1.32- 1.43;P<0.001). The disparity in DCD use wasmore prominent in the post- AC era, with lower-MELD centers having a higher proportion ofDCDs used, a higher 90-day cumulative incidence of DCD transplantation, and a higher csHR ofDCD transplant (pre-AC ref. low-MELD: mid-MELD, csHR:0.56,95%CI0.45-0.71 to post-ACcsHR:0.46,95%CI0.38-0.56; and high- MELD, pre-AC csHR:0.09,95%CI0.06-0.15 to post-ACcsHR:0.08,95%CI0.05-0.12; all P<0.001) (Figure 1). Using a structural Bayesian time-series model, the ACpolicy was associated with an increase only in the actual monthly DCD transplants in low- MELD centers (Actual 21, predicted 14; posterior tail-area probability P=0.001), whereas it wasassociated with an increase in both DBD and DCD transplants in mid- and high-MELD centers. Conclusions: While AC-based liver allocation may improve waitlist outcomes, regional variation exists in the drivers of such outcomes between centers, including an increased use of DCD LTs in low-MELD centers. (Figure Presented).
Volume
22
First Page
473
