Background: Organ Procurement and Transplantation Network and United Network for Organ Sharing (OPTN/UNOS) implemented the Share 35 policy in June 2013 to prioritize the sickest patients awaiting liver transplantation (LT). However, Model for End-Stage Liver Disease (MELD) score does not incorporate hepatic encephalopathy (HE), an independent predictor of waitlist mortality.
Aim: To evaluate the impact of severe HE (grade 3-4) on waitlist outcomes in MELD ≥ 30 patients.
Methods: Using the OPTN/UNOS database, we evaluated LT waitlist registrants from 2005-2014. Demographics, comorbidities, and waitlist survival were compared between four cohorts: MELD 30-34 with severe HE, MELD 30-34 without severe HE, MELD ≥ 35 with severe HE, and MELD ≥ 35 without severe HE.
Results: Among 10,003 waitlist registrants studied, 41.6% had MELD score 30-34 and 58.4% had MELD ≥ 35. Patients with severe HE had a higher 90-day waitlist mortality in both MELD 30-34 (severe HE 71.1% vs. no HE 56.6%; p < 0.001) and MELD ≥ 35 subgroups (severe HE 85% versus no HE 74.2%; p < 0.001). MELD 30-34 patients with severe HE had similar 90-day waitlist mortality as MELD ≥ 35 patients without severe HE (71.1 vs. 74.2%, respectively; p = 0.35). On multivariate Cox proportional hazards modeling, MELD ≥ 30 patients had 58% greater risk of 90-day waitlist mortality than those without severe HE (HR 1.58, 95% CI 1.53-1.62; p < 0.001).
Conclusion: Patients awaiting LT with MELD score of 30-34 and severe HE should receive priority status for organ allocation with exception MELD ≥ 35.
Keywords: Liver transplantation; MELD; Severe hepatic encephalopathy; Share 35 policy; Waitlist mortality.