Supplementary Material for: Impact of Muscle Mass on Survival in Patients with Sepsis: A Systematic Review and Meta-Analysis

Introduction: The aim of this study is to investigate the association between loss of muscle mass and prognosis of sepsis. Methods: Six databases, including PubMed, Embase, Cochrane Library, Web of Science, Scopus, and Ovid, were searched by the deadline of August 18, 2020. A meta-analysis was conducted on the collected data by means of a random-effects model. The quality of each included article was assessed according to the Newcastle-Ottawa Scale. Results: Out of 1,819 references, 6 articles and 1 conference abstract were included. Sepsis patients with a loss of muscle mass or sarcopenia had higher mortality (risk ratio [RR]: 1.94, 95% confidence intervals [CI]: 1.59–2.37; I-squared = 18.7%, p < 0.001). The RR of mortality within 30 days (RR: 2.31, 95% CI: 1.78–2.99, p < 0.001) was higher than that of mortality over 30 days. Loss of psoas muscle mass, as evaluated by CT, showed the highest RR of sepsis mortality. In addition, based on data on overall survival retrieved from 4 trials, the pooled hazard ratio (HR) for patients with a loss of muscle mass or sarcopenia was 3.04. Subgroup analysis showed that survival time was the main source of heterogeneity for the overall HR. Furthermore, the scanning areas of muscle mass in survival patients were 0.33 cm2/m2 higher than those measured in deceased patients. Conclusion: A loss of muscle mass, as evaluated by CT scan, was associated with a poor outcome in sepsis.