Prediction of Walking Independence in Older Women with Vertebral Compression Fracture Using Phase Angle: A Preliminary Study Using Propensity Score

Abstract

Objectives: This study aimed to clarify whether phase angle can be a predictor of walking independence in older women with vertebral compression fractures (VCFs) and to determine a clinically usable cutoff value. Methods: We retrospectively assessed data of older women (n=59; median age, 83.0 years) with VCFs. Propensity score-matching and logistic regression were performed to examine the association between phase angle at admission and walking independence at discharge. The cutoff value for the phase angle at admission for predicting walking independence was calculated based on the receiver operating characteristic curve. Results: Thirty-one patients (52.5%) could walk independently at discharge. Thirty patients were extracted from the independent and non-independent groups according to the propensity score. After propensity score matching, there was no significant difference between the groups for age, medical history, knee extension strength, skeletal muscle mass index, mini nutritional assessment-short form score, or revised Hasegawa’s dementia scale score. However, the phase angle of the independent group was significantly higher than that of the non-independent group (P<0.05). Logistic regression revealed that phase angle at admission was significantly associated with walking independence at discharge (odds ratio, 12.2; 95% confidence interval, 2.1–72.0; P<0.01). The area under the receiver operating characteristic curve was 0.868, and the calculated phase angle cutoff value was 3.55°. Conclusions: This study revealed that the phase angle can predict walking independence in older women with VCFs. The cutoff values for women calculated in this study can be used as a simple and objective predictive index of walking independence.