Improved Survival With Higher-risk Donor Grafts in Liver Transplant With Acute-on-chronic Liver Failure

Abstract

Background. Use of higher-risk grafts in liver transplantation for patients with acute-on-chronic liver failure (ACLF) has been associated with poor outcomes. This study analyzes trends in liver transplantation outcomes for ACLF over time based on the donor risk index (DRI). Methods. Using the Organ Procurement and Transplantation Network and the United Network for Organ Sharing registry, 17300 ACLF patients who underwent liver transplantation between 2002 and 2019 were evaluated. Based on DRI, adjusted hazard ratios for 1-y patient death were analyzed in 3 eras: Era 1 (2002-2007, n=4032), Era 2 (2008-2013, n=6130), and Era 3 (2014-2019, n=7138). DRI groups were defined by DRI<1.2, 1.2-1.6, 1.6-2.0, and >2.0. Results. ACLF patients had significantly lower risks of patient death within 1 y in Era 2 (adjusted hazard ratio, 0.69; 95% confidence interval, 0.61-0.78; P<0.001) and Era 3 (adjusted hazard ratio, 0.48; 95% confidence interval, 0.42-0.55; P<0.001) than in Era 1. All DRI groups showed lower hazards in Era 3 than in Era 1. Improvement of posttransplant outcomes were found both in ACLF-1/2 and ACLF-3 patients. In ACLF-1/2, DRI 1.2 to 1.6 and >2.0 had lower adjusted risk in Era 3 than in Era 1. In ACLF-3, DRI 1.2 to 2.0 had lower risk in Era 3. In the overall ACLF cohort, the 2 categories with DRI>1.6 had significantly higher adjusted risks of 1-y patient death than DRI<1.2. When analyzing hazards in each era, DRI>2.0 carried significantly higher adjusted risks in Eras 1 and 3‚ whereas DRI 1.2 to 2.0 had similar adjusted risks throughout eras. Similar tendency was found in ACLF-1/2. In the non-ACLF cohort, steady improvement of posttransplant outcomes was obtained in all DRI categories. Similar results were obtained when only hepatitis C virus-uninfected ACLF patients were evaluated. Conclusions. In ACLF patients, posttransplant outcomes have significantly improved, and outcomes with higher-risk organs have improved in all ACLF grades. These results might encourage the use of higher-risk donors in ACLF patients and provide improved access to transplant.