Phase Angle and Body Composition in Breast Cancer Survivors Compared to Healthy Age-Matched Women

Abstract

Breast cancer survivors (BCS) experience well documented treatment induced alterations in body composition, particularly the loss of lean mass (LM) and bone mineral density. Less is known about the treatment-related effects on phase angle, body cell mass (BCM), extracellular mass (ECM) and the ratio of ECM/BCM. Phase angle is an objective indicator of cellular health and integrity, and BCM is a measure of the actively metabolizing component of LM that also decreases with age. A phase angle less than 5° is indicative of poorer cellular health and nutritional status. An ECM/BCM ratio less than 1.0 is optimal. PURPOSE: To identify any differences in measures of body composition, phase angle, BCM, ECM and ECM/BCM in BCS compared to healthy age-matched women (HC). METHODS: Thirty post-menopausal BCS (stages 0-III) (age: 57 ± 8yrs; BMI: 26.4 ± 4.8 kg/m2) and 26 HC (age: 58 ± 7 yrs; BMI: 26.9 ± 5.3 kg/m2) participated in this cross-sectional study. After an 8 hr fast, whole body bioelectric impedance analysis was used to assess measures of body composition including lean mass, fat mass, body fat (%), phase angle, BCM, ECM, and ECM/BCM. Data were analyzed via one-way ANOVA. Significance was accepted at p<0.05. RESULTS: There were no significant differences in lean mass (BCS: 45.7 ± 5.7; HC: 47.0 ± 7.1 kg), fat mass (BCS: 24.4 ± 8.3; HC: 25.7 ± 8.2 kg), body fat % (BCS: 34.0 ± 6.0; HC: 34.8 ± 5.7 %), BCM (BCS: 20.9 ± 3.0; HC: 21.3 ± 2.8 kg), ECM (BCS: 34.9 ± 3.1; HC: 25.2 ± 3.9 kg), ECM/BCM (BCS: 1.20 ± 0.1; HC: 1.18 ± 0.1), phase angle (BCS: 6.06 ± 0.7; HC: 6.17 ± 1.0 °). Only one BCS had a phase angle less than 5°. CONCLUSION: Our findings suggest that BCS that are at least five years into survivorship appear to have similar phase angle, BCM, ECM, ECM/BCM as HC. Future research should be conducted to determine the effects of cancer treatments on these phase angle, BCM and ECM/BCM in BCS that have recently completed treatment.