Pectoral muscle area index is an independent protective factor for mortality in sepsis patients: a retrospective observational study.

Background: Sepsis is an infection-induced systemic inflammatory response involving multiple mediators. Identifying risk factors for mortality in patients with sepsis is important for determining treatment strategies. Sarcopenia is a systemic pathology of the skeletal muscles associated with poor outcomes in patients with sepsis. However, there exists a gap in the literature regarding the thoracic muscle area and early outcomes of sepsis. Thus, this study investigated the relationship between 28-day survival and indicators of sarcopenia (pectoral muscle area and pectoral muscle density) from chest computed tomography images of patients with sepsis.

Methods: Patients (n = 134, median age = 75 years) who met the Sepsis-3 diagnosis criteria were included. Pectoral muscle area and density were measured in patients who underwent pulmonary computed tomography within ±3 days of admission. Univariate and multivariable factors associated with 28-day mortality were evaluated via Cox regression analysis. Factors with a single-factor p  <  0.05 were included in the multivariate Cox regression analysis to evaluate the factors associated with 28-day mortality in sepsis.

Results: In this study, 88 patients survived, whereas 46 did not survive at the 28-day mark. Body mass index (BMI) (P = 0.044), pectoral muscle area (P = 0.005), pectoral muscle density (P = 0.008), and pectoral muscle area index (P = 0.003) significantly differed between patients who survived and those who did not survive. BMI was positively correlated with pectoral muscle area (r = 0.516, P  <  0.001) and index (r = 0.560, P  <  0.001). Acute Physiology and Chronic Health Evaluation II score (hazard ratio (HR) = 1.119, P  <  0.001) constituted an independent risk factor for 28-day mortality, whereas the pectoral muscle area index (HR, 0.847; P = 0.027) was a protective factor for 28-day mortality in patients with sepsis. The pectoral muscle area index was associated with a reduced risk of early mortality in patients with sepsis.