Usefulness of the Phase Angle in Evaluating Locomotive Syndrome in Cancer Patients

Background: Locomotive syndrome (LS), a condition characterized by impaired mobility due to locomotive organ dysfunction, is highly prevalent among patients with cancer. The phase angle (PhA), measured via bioelectrical impedance analysis (BIA), reflects cellular health and nutritional status. This study aimed to investigate the association between LS and the PhA in patients with cancer. Methods: This cross-sectional study included hospitalized patients who underwent cancer treatment. The assessed variables included age, sex, body mass index (BMI), gait speed, grip strength, PhA, and the outcomes of LS risk assessment using the stand-up test, two-step test, and the 25-Geriatric Locomotive Function Scale (GLFS25). Results: A total of 190 patients (57 females, 133 males; mean age, 62.6 ± 17.2 years) were analyzed. The PhA was significantly negatively correlated with the LS stage (rs = -0.507, p < 0.001). Similarly, a significant negative correlation was observed between the PhA and each LS risk test, namely, the stand-up test, two-step test, and GLFS25. Furthermore, the PhA was identified as an independent and significant factor associated with LS progression (odds ratio, 0.361; 95% confidence interval, 0.221-0.588; p < 0.001). More effective and rapid than completing the full range of LS risk tests, measuring the PhA represents a convenient and practical tool for the early screening of mobility decline. Conclusions: The PhA is a simple and effective parameter for assessing mobility decline in patients with cancer. It is a potential clinical indicator for initiating rehabilitation interventions aimed at preventing the onset and progression of LS.