Living-donor liver transplant recipients gained an additional 13-17 years of life, compared with patients who remained on the wait list, according to a retrospective case-control study.
The data suggest that the life-years gained are comparable to or greater than those conferred by either other lifesaving procedures or liver transplant from a deceased donor, wrote the researchers, led by Whitney Jackson, MD, assistant professor of gastroenterology and medical director of living-donor liver transplantation at the University of Colorado Anschutz Medical Campus.
“Despite the acceptance of living-donor liver transplant as a lifesaving procedure for end-stage liver disease, it remains underused in the United States,” the authors wrote in. “This study’s findings challenge current perceptions regarding when the survival benefit of a living-donor transplant occurs.”
Dr. Jackson and colleagues conducted a retrospective, secondary analysis of the Scientific Registry of Transplant Recipients database for 119,275 U.S. liver transplant candidates and recipients from January 2012 to September 2021. They assessed the survival benefit, life-years saved, and the Model for End-Stage Liver Disease incorporating sodium levels (MELD-Na) score at which the survival benefit was obtained, compared with those who remained on the wait list.
The research team included 116,455 liver transplant candidates who were 18 and older and assigned to the wait list, as well as 2,820 patients who received a living-donor liver transplant. Patients listed for retransplant or multiorgan transplant were excluded, as were those with prior kidney or liver transplants.
The mean age of the study participants was 55 years, and 63% were men. Overall, 70.2% were White, 15.8% were Hispanic or Latinx, 8.2% were Black or African American, 4.3% were Asian, 0.9% were American Indian or Alaska Native, and 0.2% were Native Hawaiian or Pacific Islander. The most common etiologies were alcoholic cirrhosis (23.8%) and nonalcoholic steatohepatitis (15.9%).
Compared with patients on the wait list, recipients of a living-donor liver transplant were younger, more often women, more educated, and more often White. A greater proportion of transplant recipients had a primary etiology of nonalcoholic steatohepatitis (19.8%) and cholestatic liver disease (24.1%). At wait list placement, one-third of candidates had a MELD-Na score of 14 or higher.
The research team found a significant survival benefit for patients receiving a living-donor liver transplant based on mortality risk and survival scores. The survival benefit was significant at a MELD-Na score as low as 11, with a 34% decrease(95% confidence interval [CI], 17.4%-52.0%) in mortality compared with the wait list. In addition, mortality risk models confirmed a survival benefit for patients with a MELD-Na score of 11 or higher at 1 year after transplant (adjusted hazard ratio, 0.64; 95% CI, 0.47-0.88; P = .006). At a MELD-Na score of 14-16, mortality decreased by about 50% (aHR, 0.47; 95% CI, 0.34-0.66; P < .001).
The probability of death from a living-donor liver transplant for patients with very low MELD-Na scores (between 6 and 10) was greater than that for patients on the wait list for the first 259 days, at which point the risk of death for both groups was equal. At 471 days, the probability of survival in both groups was equal. As the MELD-Na score increased, both the time to equal risk of death and the time to equal survival decreased, demonstrating that the survival benefit occurs much earlier for patients with a higher MELD-Na score.
Analysis of life-years from transplant showed living-donor transplant recipients gained 13-17 life-years compared to those who didn’t receive one.
“Living-donor liver transplantation is a valuable yet underutilized strategy to address the significant organ shortage and long waiting times on the transplant list in the U.S.,” said Renu Dhanasekaran, MD, PhD, assistant professor of gastroenterology and hepatology at Stanford (Calif.) University.
Dr. Dhanasekaran, who wasn’t involved with this study, also welcomed the finding that living-donor liver transplantation can benefit patients with low MELD-Na scores, even below the expected cutoff at 15. According to the study authors,had suggested benefit would be seen only at MELD-Na 15 and above.
“In my practice, I have several patients whose symptoms are out of proportion to their MELD score, and data like this will convince them and their potential donors to avail a transplant at an earlier stage,” she said.
The findings challenge the current paradigm around the timing of referral for a liver transplant and may have ramifications for allocation policies for deceased donors, the study authors wrote. The data can also help to contextualize risk-benefit discussions for donors and recipients.
“Donating a part of one’s liver to save a patient suffering from end-stage liver disease is an incredible act of selfless love,” Dr. Dhanasekaran said. “I hope strong positive data from studies like this one encourage more donors, patients, and transplant centers to expand the use of [living-donor liver transplant].”
The authors reported no grant support or funding sources for this study. One author disclosed being married to the current chair of the United Network for Organ Sharing’s Liver and Intestinal Organ Transplantation Committee. No other conflicts of interest were reported. Dr. Dhanasekaran reported no relevant disclosures.