Increasing practice and acceptable outcomes of high-MELD living donor liver transplantation in the USA

Abstract

Introduction: Recent deceased-donor allocation changes in the US may have increased high-MELD living-donor liver transplantation (LDLT); however, outcomes in these patients remain poorly defined. We aimed to examine the impact of MELD score on LDLT outcomes. Methods: Using UNOS data (01/01/2010-12/31/2021), LDLT recipients were identified and stratified into low- ( < 15), intermediate- (15-24), and high-MELD ( ≥ 25) groups. We compared outcomes between MELD-stratified LDLT groups and between MELD-stratified LDLT and donation after brain death liver transplantation (DBDLT) recipients. We used Kaplan-Meier analysis to compare graft survival rates and multivariable Cox proportional hazards modeling to identify factors associated with graft outcomes. Results: Of 3,558 LDLTs, 1,605 (45.1%) were low-MELD, 1,616 (45.4%) intermediate-MELD, and 337 (9.5%) high-MELD. Over the study period, the annual number of LDLTs increased from 282 to 569, and the proportion of high-MELD LDLTs increased from 3.9% to 7.7%. Graft survival was significantly higher in low-MELD versus high-MELD LDLT recipients (adjusted HR = 1.36, 95%CI:1.03-1.79); however, 5-year survival exceeded 70.0% in both groups. We observed no significant difference in graft survival between high-MELD LDLT and high-MELD DBDLT recipients (adjusted HR: 1.25, 95%CI:0.99-1.58), with 5-year survival of 71.5% and 77.3%, respectively. Low LDLT center volume ( < 3 LDLTs/year) and recipient life support requirement were both associated with inferior graft outcomes among high-MELD LDLT recipients. Conclusion: While higher MELD scores confer graft failure risk in LDLT, high-MELD LDLT outcomes are acceptable with similar outcomes to MELD-stratified DBDLT recipients. Future practice guidance should consider expansion of LDLT recommendations to high-MELD recipients in centers with expertise to help reduce donor shortage.