| Abstract: | BACKGROUND: Historically, patients with primary biliary cholangitis (PBC) experience waitlist mortality and low rates of liver transplant (LT). Herein, the impact of MELD-Na based allocation on PBC waitlist mortality was examined. METHODS: Adult patients with PBC were compared to those with alcohol-related liver disease (ALD) or non-alcoholic steatohepatitis (NASH) listed for LT from 2013 to 2019 in OPTN. Competing risk regression evaluated waitlist mortality in the MELD and MELD-Na eras using propensity score weights. RESULTS: Overall, 1508 patients with PBC, 13581 with ALD, and 10455 with NASH were examined. In the MELD-Na era, 24-month cumulative incidence of waitlist mortality for PBC was 23.0% (95%CI 19.7-26.5%), ALD 13.9% (95%CI 13.1-14.8%), and NASH 20.0% (95%CI 18.9-21.2%). Using propensity score weights, adjusted risk of waitlist mortality was higher for PBC versus ALD (HR = 1.45, 95%CI 1.22-1.71) and NASH (HR = 1.32, 95%CI 1.14-1.55). Furthermore, among PBC, waitlist mortality risk per five-point elevation in MELD-Na (HR = 1.22, 95%CI 1.11-1.35) and Karnofsky score ≤30% (HR = 2.02, 95%CI 1.39-2.92) was significantly higher than among ALD (HR = 1.08, 95%CI 1.04-1.13; HR = 1.28, 95%CI 1.10-1.49) and NASH (HR = 1.05, 95%CI 1.00-1.09; HR = 1.16, 95%CI .99-1.37; all P-interactions < .05). CONCLUSIONS: The MELD-Na score continues to underestimate risk of waitlist death for patients with PBC relative to ALD and NASH and highlights need for additional score modifications or exceptions. |