The combination of a male donor's high muscle mass and quality is an independent protective factor for graft loss after living donor liver transplantation.

We evaluated the hypothesis that grafts from donors with high muscle mass and quality may have a better outcome after living-donor-liver-transplantation (LDLT) than those from usual donors. A total of 376 primary adult-to-adult LDLT cases were enrolled in this study. Donor skeletal muscle mass index (SMI) and intramuscular adipose tissue content (IMAC) were used as markers of muscle mass and quality. In male donor cases (n = 198), those with higher SMI and lower IMAC than age-adjusted values were defined as the "high muscularity donors" (n = 38) and the others were defined as the "control" (n = 160). The high muscularity donor showed better 1-year (97% vs 82%, P = .020) and overall graft survival rate (88% vs 67%, P = .024) than the control group after LDLT. Contrastingly, the influence of the muscularity was not observed in female donor cases. Multivariable analysis including donor age confirmed that a high muscularity donor was an independent protective factor for overall graft survival after LDLT (hazard ratio, 0.337; 95% CI: 0.101-0.838; P = .017). Our study first confirmed that high muscle mass and quality of a male donor is a protective factor of allograft loss after LDLT, independently from donor age.