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.