BACKGROUND: Although ABO-incompatible liver transplantation (ABOi LT) has undergone remarkable progress, the prognostic factors are poorly understood. This study aimed to elucidate the preoperative factors affecting graft survival after ABOi LT. METHODS: Patients who underwent ABOi LT between January 2012 and December 2020 at a single institution in South Korea were retrospectively reviewed. A total of 146 recipients, including 34 patients with graft loss, were analyzed. RESULTS: In the multivariate Cox proportional hazard model, recipient age (≥55 y
hazard ratio, 2.47
95% confidence interval, 1.18-5.19
P = 0.017) and donor ABO type (donor A, hazard ratio, 3.12
95% confidence interval, 1.33-7.33
P = 0.009) were significantly associated with an increased risk of graft loss. The most common cause of graft loss was recipient death due to bacterial infection (15/34, 44.1%). Both recipient age and donor ABO type were associated with an increased risk of recipient death due to bacterial infections. The incidence of complications after ABOi LT, including antibody-mediated rejection and diffuse intrahepatic biliary stricture, did not differ according to recipient age or donor ABO type. CONCLUSIONS: These findings suggest that recipient age and donor ABO type should be considered when preparing for ABOi LT. Careful monitoring and care after transplantation are required for recipients with preoperative risk factors.