Utility of the simplified measurements of muscle mass in patients with gastrointestinal and chronic liver diseases

Sarcopenia is an important prognostic factor in patients with gastrointestinal and chronic liver diseases. Computed tomography and bioelectrical impedance analysis are the gold standards for measuring skeletal muscle mass for the diagnosis of decreased muscle mass, but there are some institutions where BIA and CT cannot be carried out. We evaluated the utility of simplified methods for measuring muscle mass; the psoas muscle mass index (PMI) method, simple PMI method, and arm muscle area (AMA) method. This retrospective study included 331 patients with gastrointestinal diseases and 81 patients with chronic liver diseases who were admitted from June 2018 to December 2019 at Municipal Hospital of Kofu. The skeletal muscle mass was measured using the PMI via the volume analyzer SYNAPSE VINCENT ver3.0, simple PMI based on CT imaging, and AMA method. Positive correlations were found between muscle mass measured by PMI and simple PMI, PMI and AMA, and simple PMI and AMA in patients with gastrointestinal diseases (correlation coefficients = 0.76, 0.57, 0.47, respectively, p < 0.001). Positive correlations were observed between muscle mass measured by PMI and simple PMI, PMI and AMA, and simple PMI and AMA in chronic liver diseases (correlation coefficients = 0.77, 0.53, 0.45, respectively, p < 0.001). Measurement of muscle mass by the AMA method showed some correlation with the PMI method. Measurement of muscle mass by the simple PMI method showed correlation with the PMI method. These simplified methods can be alternative methods of evaluating muscle mass in patients with gastrointestinal and chronic liver disease.