Association of the Bioimpedance Phase Angle and Quality of Life in Postmenopausal Osteoporosis.

Objectives: Osteoporosis patients with fragility fractures and vertebral deformities have impaired quality of life (QOL). The phase angle, an index calculated from bioelectrical impedance analysis (BIA) measurements, has been reported to be related to clinical outcomes, mortality, and QOL in various diseases. We aimed to investigate the relationship between the phase angle and QOL in patients with postmenopausal osteoporosis.

Methods: 81 female patients treated for postmenopausal osteoporosis from September 2019 to March 2020 underwent measurement of bone mineral density (BMD) by dual-energy X-ray absorptiometry, body composition by BIA, and QOL by the 36-item Short-Form Health Survey (SF-36).

Results: The phase angle showed significant positive correlations with physical functioning (r = 0.270, p = 0.015) and physical component summary (PCS) (r = 0.251, p = 0.024) of the SF-36. The phase angle showed significant positive correlations with appendicular skeletal muscle mass index (ASMI) (r = 0.456, p < 0.001), lumbar spine BMD (r = 0.241, p = 0.030), and femoral neck BMD (r = 0.26, p = 0.021) and a significant negative correlation with age (r = -0.526, p < 0.001). Multiple regression analysis of the factors potentially associated with SF-36 PCS showed that the phase angle (r = 7.506, p = 0.012) was a significant contributor to PCS (R2 = 0.184).

Conclusion: The phase angle in postmenopausal osteoporotic patients was significantly related to QOL after adjusting for age, BMI, ASMI, and BMD. As the phase angle is a parameter that can be measured easily and noninvasively, it might be a useful aid for QOL assessment in osteoporotic patients.