Survival benefit of liver transplantation utilizing marginal donor organ according to ABO blood type.

ABSTRACT

BACKGROUND: The current liver transplantation (LT) allocation policy focuses on the Model for End-Stage Liver Disease (MELD) scores, often overlooking factors like blood type and survival benefits. Understanding blood types' impact on survival benefits is crucial for optimizing the MELD 3.0 classification. METHOD: This study used the United Network for Organ Sharing national registry database (2003-2020) to identify LT characteristics per ABO blood type and to determine the optimal MELD 3.0 scores for each blood type, based on survival benefits. RESULTS: The study included LT candidates aged 18 years or older listed for LT (total N=150,815; A56,546, AB5,841, B18,500, O69,928). Among these, 87,409 individuals (58.0%) underwent LT (A32,156, AB4,362, B11,786, O39,105). Higher transplantation rates were observed in AB and B groups, with lower median MELD 3.0 scores at transplantation (AB21, B24 vs. A/O26, p<0.01) and shorter waiting times (AB101 days, B172 days vs. A211 days, O201 days, p<0.01). A preference for Donation after Cardiac Death (DCD) was seen in A and O recipients. Survival benefit analysis indicated that B blood type required higher MELD 3.0 scores for transplantation than A and O (Donation after Brain Death transplantation ≥15 in B vs. ≥11 in A/O; DCD transplantation ≥21 in B vs. ≥11 in A, ≥15 in O). CONCLUSION: The study suggests revising the allocation policy to consider blood type for improved post-LT survival. This calls for personalized LT policies, recommending higher MELD 3.0 thresholds, particularly for individuals with type B blood.