Living Donor Liver Transplantation in the United States: Evolution of Frequency, Outcomes, Center Volumes, and Factors Associated With Outcomes.

Recent modifications in organ allocation policies and increases in chronic liver diseases may have resulted in important changes in living donor liver transplantation (LDLT) in the United States. We examined the trends, outcomes, and factors associated with outcomes in adult LDLT. United Network for Organ Sharing data on 2566 adult LDLT recipients who received transplants from January 1, 2010, through December 31, 2019, were analyzed. LDLT graft and patient survival rates were compared with propensity score-matched deceased donor liver transplantation recipients by the Kaplan-Meier curve estimator. The association between preceding LDLT frequency and subsequent outcomes were assessed by Cox proportional hazards mixed effects modeling. After a stable annual frequency of LDLTs from 2010 to 2014 (~200 per year), the number of LDLTs doubled to 440 in 2019. The 1-year and 5-year graft survival rates for LDLT recipients were 88.4% and 78.1%, respectively, compared with 92.5% and 80.7% in the propensity score-matched donation after brain death recipients (P = 0.005), respectively. Older donor age and recipient diabetes mellitus and life support requirement were significantly associated with graft failure among LDLT recipients (P values <0.05). Average preceding LDLT frequencies of <3 per year, 3 to 20 per year, and >20 per year resulted in 1-year graft survival rates of 82%, 88% to 89%, and 93%, respectively (P values <0.05). There were 3 living donor deaths (0.12%). The frequency of LDLTs has doubled during the past decade, with good outcomes and acceptable donor safety profiles. However, there appear to be varying threshold transplant frequencies (volume/unit time) associated with acceptable (88%-89%) and aspirational (93%) 1-year graft survival rates. These data should be reassuring and encourage LDLT practice as efforts continue to expand the donor pool.