Association between Multi-Frequency Phase Angle and Survival in Patients with Advanced Cancer.

CONTEXT: The ability to predict survival accurately has implications in clinical decision making.

OBJECTIVE: We determined the association of phase angle obtained from multi-frequency bioelectric impedance analysis (MF-BIA) with overall survival in patients with advanced cancer.

METHODS: We included consecutive patients with advanced cancer who had an outpatient palliative care consultation. MF-BIA assessed phase angle at three different frequencies (5 kHz/50 kHz/250 kHz) on each hemibody (right/left). Survival analysis was conducted using the Kaplan Meier method, log rank test and multivariate Cox regression analysis.

RESULTS: Among 366 patients, the median overall survival was 250 days (95% confidence interval 191-303 days). The mean phase angle for 5 kHz, 50 kHz and 250 kHz were 2.2°, 4.4°, 4.2° on the right, and 2.0°, 4.2° and 4.1° on the left, respectively. For all 6 phase angles, a lower value was significantly associated with a poorer overall survival (P<0.001). After adjusting for cancer type, performance status, weight loss and inflammatory markers, phase angle remained independently associated with overall survival (hazard ratio 0.85 per degree increase, 95% confidence interval 0.72-0.99; P=0.048).

CONCLUSION: Phase angle represents a novel objective prognostic factor in outpatient palliative cancer care setting, regardless of frequency and body sides.

Copyright © 2016. Published by Elsevier Inc.

KEYWORDS: Electric impedance; forecasting; neoplasms; palliative care; prognosis; survival

PMID: 28042079 DOI: 10.1016/j.jpainsymman.2016.09.016