Phase angle is related to physical function and quality of life in preoperative patients with lumbar spinal stenosis

Purpose Lumbar spinal stenosis (LSS) causes various symptoms, which can interfere with daily life and Quality of Life (QOL). Evaluating both patients’ physical function and QOL and helping them to improve is the focus of rehabilitation. Phase angle (PhA) assessment has been widely used to measure body composition, and it has been reported to reflect physical function and QOL. The purpose of this study was to investigate the relationship between PhA and physical function, physical activity, and QOL in patients with LSS. Methods PhA, handgrip strength, walking speed, timed up and go test (TUG), Life Space Assessment (LSA), Prognostic Nutritional Index (PNI), Japanese Orthopaedic Association back pain evaluation questionnaire (JOABPEQ), and EQ-5D were assessed. Multiple regression analysis was conducted to investigate the relationship of PhA to physical function, physical activity, and QOL using. Results Statistical analysis was performed on 104 patients with LSS. The results of multiple regression analysis of PhA adjusted for age, gender, and BMI (Model 1) and PhA adjusted for age, gender, BMI, and PNI (Model 2) compared with physical function and physical activity showed significant correlations respectively (P<0.05) in handgrip strength, walking speed, TUG, and LSA. In QOL assessment, both models showed a significant correlation (P<0.05) with lumbar function in JOABPEQ and a significant trend (P<0.1) in EQ-5D. Conclusion PhA in LSS patients in this study was associated with physical function and QOL, and may be a useful new tool for clinical evaluation in preoperative LSS patients.