Offspring Versus Nonoffspring to Parent Living Donor Liver Transplantation: Does Donor Relationship Matter?

Background: Offspring (donor) to parent (recipient) transplant is the most common form of living donor liver transplant in the United States. In kidney transplantation, it has been suggested that female recipients of offspring living donor kidney allografts have inferior outcomes. It is unknown whether such a phenomenon also occurs following living donor liver transplantation.
Methods: A retrospective analysis was completed of recipients of a living donor liver transplant from January 1998 to January 2018 in the Organ Procurement and Transplantation Network/United Network for Organ Sharing database. Patients were grouped as having received a living donor liver allograft from either an offspring or a nonoffspring, with exactly 3 HLA matches, as would be expected between an offspring and parent. Graft and patient survival were analyzed using Cox proportional hazards modeling.
Results: A total of 279 offspring to parent and 241 nonoffspring donor liver transplants were included in the analysis. Female recipients of offspring liver allografts had both inferior 10-year graft (52% versus 72%; P < 0.001) and patient survival (52% versus 81%; P < 0.001) compared with female recipients of nonoffspring allografts. No such difference in outcomes was discovered among male recipients. A stratified analysis of sex of offspring donors to female recipients demonstrated that donor male gender was associated with graft failure (HR = 2.87; P = 0.04) and mortality (hazard ratio = 3.89; P = 0.03). Again, this association was not seen with male recipients.
Conclusions: Among female recipients, offspring to parent living donor liver transplantation yields inferior long-term graft and patient survival. Furthermore, among offspring donors, male sex was strongly associated with inferior outcomes. These findings have significant implications for donor selection.