Abstract
AIM: This study assessed the prognostic value of sarcopenia and myosteatosis for survival following liver transplantation using CT-derived skeletal muscle index (SMI) and skeletal muscle radiation attenuation (SMRA). BACKGROUND: Sarcopenia and myosteatosis are common in liver transplant (LT) candidates and may affect postoperative outcomes. METHODS: This retrospective cohort study analyzed 79 LT recipients (aged 17-75 years) at Taleghani Hospital, Tehran, Iran, from October 2019 to November 2023, excluding patients with malignancy or cardiovascular disease. Non-contrast-enhanced CT scans at the third lumbar vertebra were analyzed using SliceOmatic software to quantify SMI and SMRA. Sarcopenia was defined using AWGS-adapted criteria for CT: low SMI (<42 cm²/m² for men, <38 cm²/m² for women), reduced handgrip strength (<30 kg for men, <20 kg for women), or reduced gait speed (<1 m/s). Sarcopenia was classified as pre-sarcopenia (low SMI), sarcopenia (low SMI with either deficit in hand grip strength or gait speed), severe sarcopenia (low SMI with both deficits), or sarcopenic obesity (sarcopenia with BMI ≥30 kg/m²). Myosteatosis was defined by SMRA (<41 HU for BMI <25 kg/m²; <33 HU for BMI ≥25 kg/m²). The Cox proportional hazards model and Kaplan-Meier analysis assessed survival predictors (P<0.05). RESULTS: Among 79 recipients (58.2% male, mean age 47.2±13.7 years), 77.2% had myosteatosis and 34.2% had pre-sarcopenia. Over 60,173 person-days, 17 deaths occurred. Myosteatosis (HR 2.15, 95% CI 1.03-4.48), elevated bilirubin (HR 1.04, 95% CI 1.02-1.07 per unit), and female sex (HR 2.29, 95% CI 1.19-4.14) were associated with increased mortality hazard (all P<0.05). Kaplan-Meier curves showed 5-year survival of 70-80%. CONCLUSION: Myosteatosis, elevated bilirubin, and female sex are significant predictors of mortality post-LT in this cohort. CT-derived SMRA assessment offer valuable tools for pre-transplant risk stratification, supporting targeted interventions to improve early outcomes.