Bioimpedance phase angle and sarcopenia in older patients with prostate cancer

Aim: The purpose of this study was to evaluate the factors associated with the bioimpedance phase angle (PhA) in older patients with prostate cancer, and to determine the optimal cutoff for the PhA in patients with sarcopenia and prostate cancer. Methods: This retrospective cross-sectional analysis enrolled patients with prostate cancer aged ≥60 years. Appendicular skeletal muscle mass and PhA estimated by bioimpedance analysis, grip strength, the five-time chair stand test, gait speed, the Short Physical Performance Battery, the 2-min walk test and the International Physical Activity Questionnaire Short Form were obtained at enrollment. The diagnosis of sarcopenia was based on the 2019 consensus of the Asian Working Group for Sarcopenia. Results: In total, 119 male participants (mean age = 70.7 ± 6.1 years) were available for analysis. A multivariable linear regression model revealed that age, body mass index and the maximal grip strength value were associated with the PhA. The area under the receiver operating characteristic curve value of the PhA for sarcopenia diagnosis was 0.77 (95% confidence interval 0.64–0.90, P < 0.001), with a PhA cutoff value of 4.87°. Conclusions: PhA estimated by bioimpedance analysis may be utilized as useful clinical biomarker for reflecting muscle strength and sarcopenia in older patients with prostate cancer. Geriatr Gerontol Int 2022; 22: 623–627.