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

Abstract

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.

Figure 1.. Number of living donor liver transplantations in the USA 2010 – 2019 stratified by etiology of liver disease and sub-stratified by (A) overall, (B) decompensated cirrhosis, and (C) hepatocellular carcinoma.

LDLTs, living donor liver transplantations; PSC, primary sclerosing cholangitis; HCV, hepatitis C virus; NASH, nonalcoholic steatohepatitis; ALD, alcohol-associated cirrhosis; DC, decompensated cirrhosis; HCC, hepatocellular carcinoma.

Figure 2.. Geographic variation of living donor liver transplantations in the USA 2010 – 2019 stratified by UNOS region.

The bar charts display the (A) overall number and (B) % change between 2010 and 2019, while the maps show the number of LDLTs performed in (C) 2010 and (D) 2019 in respective UNOS regions. LDLTs, living donor liver transplantations; UNOS, United Network for Organ Sharing.

Figure 3

(A) Patient & (B) Graft survival for living-donor liver transplant (LDLT) recipients in the U.S. 2010-2019 vs. propensity-score matched donation after brain death liver transplant (DBD LT) recipients

Figure 4.

One-year graft survival for living-donor liver transplants (LDLTs) in the U.S. 2010-2019, stratified by the number of LDLTs performed in the combined two years preceding the transplant date for each individual recipient at respective transplant centers. A volume effect was observed, with the lowest transplant volume having the most inferior outcomes, while the highest transplant volume having the best outcomes. The pairwise comparisons are also provided in the form of p values.

Figure 5.

Graft survival rates for LDLTs stratified by (A) relative versus nonrelative donors and (B) offspring versus nonoffspring donors in the United States.