Use of skeletal muscle index as a predictor of short-term mortality in patients with acute-on-chronic liver failure.

Sarcopenia is a well-recognized factor affecting the prognosis of chronic liver disease, but its impact on acute decompensation underlying chronic liver disease is unknown. This study evaluated the impact of sarcopenia on short-term mortality in patients with acute-on-chronic liver failure (ACLF). One hundred and seventy-one ACLF patients who underwent abdominal CT between 2015 and 2019 were retrospectively included in this study. Skeletal muscle index at the third lumbar vertebrae (L3-SMI) was used to diagnose sarcopenia.The ACLF patients in this study had a L3-SMI of 41.2 ± 8.3 cm2/m2 and sarcopenia was present in 95/171 (55.6%) patients. Body mass index (BMI), cirrhosis, and higher serum bilirubin were independently associated with sarcopenia. Following multivariate Cox regression analysis, cirrhosis (hazard ratio (HR) 2.758, 95%CI 1.323-5.750), serum bilirubin (HR 1.049, 95%CI 1.026-1.073), and international normalized ratio (INR) (HR 1.725, 95%CI 1.263-2.355) were associated with 3-month mortality (P < 0.05), whereas L3-SMI and sarcopenia were not. A subgroup analysis of the factors related to sarcopenia showed that sarcopenia was still not predictive of short-term outcome in ACLF patients. L3-SMI and sarcopenia are not associated with short-term mortality in patients with ACLF.