Phase Angle as a Prognostic Predictor for Physical Function in Fragile Osteoporotic Fracture Patients

ABSTRACT Objectives: This study aimed to determine whether the phase angle is associated with physical function at discharge and discharge destination in patients with osteoporotic fragile fractures. Methods: This retrospective cohort study included patients with fragile osteoporotic fractures who were admitted to a convalescent rehabilitation ward. The phase angle was calculated using a body composition meter and bioelectrical impedance analysis. The primary outcome was the Functional Independence Measure motor (FIM-motor) score at discharge, and the secondary outcome was discharge to home. Multivariate analysis was used to determine the association between phase angle and FIM-motor scores at discharge and discharge to home. Results: The study included 127 patients (108 women, age 81.2 ± 9.7 years). The median phase angle on admission was 4.1° for men and 3.6° for women. The median FIM-motor score at discharge was 83, with 92 (72.4%) patients discharged home and 35 (27.6%) discharged to a destination other than home. Multiple regression analysis adjusted for confounders revealed a significant independent association between the phase angle and FIM-motor score at discharge (β=0.262, P=0.019). However, no significant association was found between phase angle and discharge destination (odds ratio, 1.350; 95% confidence interval: 0.680–2.670, P=0.391). Conclusions: Phase angle was independently associated with physical function at discharge in patients with fragile osteoporotic fractures. For patients with a reduced phase angle on admission, a multidisciplinary approach, including exercise, nutrition, oral health, and medication, should be implemented to maximize improvement in physical function.