A Share 21 Model in Liver Transplantation: Impact on Waitlist Outcomes.

With the introduction of MELD-Na based allocation, the score at which patients benefit from liver transplantation (LT) has shifted from a score of 15 to 21. This study aimed to evaluate waitlist outcomes in patients with MELD-Na scores <21 and explore the utility of replacing "Share 15" with "Share 21". The study uses data from the OPTN/UNOS registry. All adult patients registered for LT after implementation of the MELD-Na based allocation were evaluated. Waitlist patients with initial and final scores <21 were eligible. Patients with exception scores were excluded. To explore the potential impact of a Share 21 model, patients with an initial MELD-Na score of 6-14 (Group 1) and those with a score of 15-20 (Group 2) were compared for waitlist outcomes. There were 3,686 patients with an initial score of 6-14 (Group 1) and 3,282 with a score of 15-20 (Group 2). Group 2, when compared to Group 1, showed comparable risk of mortality (adjusted hazard ratio [aHR] 1.00, P=0.97), higher transplant probability (aHR 3.25, P<0.001), and lower likelihood of removal from listing because of improvement (aHR 0.74, P=0.011). Share 21 may enhance transplant opportunities and increase parity for patients with higher MELD-Na scores without compromising waitlist outcomes.