Abstract
BACKGROUND AND AIM: Pre-transplant sarcopenia (reduced skeletal muscle mass) predicts poor outcome in cirrhosis. In contrast, whether muscle mass increases post-orthotopic liver transplantation (OLT) is not known and was studied prospectively. METHODS: Consecutive patients who underwent a comprehensive nutritional evaluation in a liver transplant nutrition clinic were included. Core abdominal muscle area was measured on abdominal computed tomography obtained pre- and post-OLT. Age- and gender-based controls were used to define sarcopenia. Measures of body composition pre-transplant were correlated with computed tomography measurements. Predictors and clinical impact of post-OLT change in muscle area were examined. In three subjects post-OLT and three controls, expression of genes regulating skeletal muscle mass were quantified. RESULTS: During the study period, 53 patients (M:F 41:12; age 56.9 ± 7.5 years) were followed up after OLT for 19.3 ± 9 months. Five patients died and another five had acute graft rejection. Pre-OLT sarcopenia was present in 33 (66.2%). Pre-transplant clinical characteristics including Child's score, MELD score, and nutritional status or post-transplantation immunosuppression regimen did not predict post-transplant change in muscle mass. New onset post-OLT sarcopenia developed in 14 patients. Loss of muscle mass post-OLT increased risk of diabetes mellitus and a trend toward higher mortality. Skeletal muscle expression of myostatin was higher and that of ubiquitin proteasome proteolytic components lower post-OLT than in controls. CONCLUSIONS: Post-transplantation sarcopenia is common and could not be attributed to pre-transplant characteristics or the type or duration of post-OLT immunosuppression. Post-transplant sarcopenia contributes to adverse consequences and strategies targeting myostatin may be beneficial.