Sarcopenia defined by psoas muscle index independently predicts long-term survival after living donor liver transplantation in male recipients

Background: The effect of sarcopenia on long-term outcomes in recipients after living donor liver transplantation (LDLT), including overall survival and hepatocellular carcinoma (HCC) recurrence, remains unclear, especially in China. Methods: From 2009 to 2015, 117 adult patients underwent LDLT in our center. In all, 82 patients who had computed tomography images reaching the third lumbar vertebra level within 1 month of LDLT were included; 70 male patients were included in the final analysis after excluding 12 female patients because of poor performance of the calculated cutoff value. Sarcopenia was defined according to the psoas muscle index (PMI) cutoff value, which was calculated based on dynamic time-dependent outcomes using X-tile software. Cox proportional hazards models were used to assess multivariate-adjusted hazards ratios (HRs) to seek potential correlations between sarcopenia and posttransplant outcomes. Results: According to the cutoff value of PMI (6.25 cm(2)/m(2)), 38 patients (54.3%) were diagnosed with sarcopenia. After an average of 63.3 months of follow-up, 21 patients died after LDLT, 16 in the sarcopenia group and 5 in the non-sarcopenia group, respectively. Sarcopenia was identified as being significantly associated with worse posttransplant overall survival in multivariate analysis, resulting in an HR of 3.22 [95% confidence interval (CI), 1.15-8.98]. Among the 50 recipients with HCC, sarcopenia was significantly associated with HCC recurrence in univariate analysis (HR 2.87, 95% CI, 1.06-7.80) but was not detected as an independent risk factor of HCC recurrence in multivariate analysis, although a trend (tendency)towards significance was observed (HR 2.60, 95% CI, 0.95-7.10; P=0.062). Conclusions: Sarcopenia defined by PMI is a feasible and reliable independent predictor of posttransplant overall survival in male LDLT candidates. However, its correlation with posttransplant HCC recurrence remains uncertain.