Background and aim: The prognosis of patients with acute-on-chronic liver failure (ACLF) is assessed on the basis of organ failure scores. Sarcopenia is associated with poor prognosis in patients with cirrhosis but has not been investigated in patients with ACLF. Hence, we evaluated whether sarcopenia was associated with short-term outcome in this population.
Patients and methods: We retrospectively included all patients with cirrhosis and ACLF hospitalised in the ICU of Lausanne University Hospital between 2010 and 2019 for whom an abdominal CT performed ± 7 days from admission was available. The lumbar-3-skeletal muscle index (L3SMI) was quantified using a deep learning-based method. Sarcopenia was defined as L3SMI ≤ 50 cm2/m2 in men and ≤ 39 cm2/m2 in women.
Results: A total of 192 patients fulfilled the inclusion criteria. Of these, 73.5% were male, with a median age of 62 (range, 53.2-70.0) years, a MELD score of 21.9 (range, 15.1-27.9) and a CLIF-C ACLF-lactate score of 71.5 (range, 64.1-80.2) on admission. The 28-day survival was 58.2% (95% confidence interval, 51.2-65.2%). The median L3SMI was 43.2 (range, 37.1-50.1) cm2/m2, with 63% of patients being sarcopenic. None of the main characteristics differed between patients randomly assigned to a derivation (N=128) vs. a validation (N=64) cohort. In the derivation cohort, logistic regression analyses on day 0 and day 3, the variables independently associated with 28-day survival were at day 0: CLIF-C ACLF- lactate on day 0 (OR 1.14, 1.07-1.22, p<0.0001) and sarcopenia (4.66, 1.78-12.20, p=0.002) and at day 3: CLIF-C ACLF-lactate on day 3 (OR 1.21, 1.12-1.30, p<0.0001) and sarcopenia (OR 3.16, 1.04-9.78, p=0.05). Based on the results of multivariate analyses, we derived two scores combining sarcopenia and the CLIF-C ACLF-lactate score on days 0 and 3, with AUROCs of 0.81 and 0.91, respectively, that outperformed the CLIF-C ACLF-lactate score alone (AUROC 0.75 on day 0 [p=0.04] and 0.88 on day 3 [p=0.03]). These scores had excellent performance in the validation set, with AUROCs of 0.87 and 0.91. None of the infection- and organ support-related variables explained the difference in outcome observed between sarcopenic and non-sarcopenic patients.
Conclusion: sarcopenia is independently associated with 28-day survival in patients with ACLF hospitalised in the ICU. Adding sarcopenia to the CLIF-C ACLF-lactate score on days 0 and 3 improved prediction of prognosis. Sarcopenia is an important parameter related to outcome and should be evaluated in patients with ACLF hospitalised in the ICU.