Bioelectrical impedance for detecting upper limb lymphedema in nonlaboratory settings

Abstract

Background: Single-frequency bioelectrical impedance has been used in clinical and research settings to measure extracellular fluid in arms. Its ease of use and low risk of user error suggests this measurement method may have advantages for use in nonlaboratory (community-based) environments when compared to other measurement methods. The purpose of this study was to evaluate the feasibility of using single-frequency bioelectrical impedance to detect upper limb lymphedema in nonlaboratory settings.

Methods and results: Using a standardized protocol, impedance ratios among healthy normal women, breast cancer survivors with lymphedema, and breast cancer survivors without lymphedema were compared with participants seated in an upright position conducive for use outside laboratory settings (community-based environments). Ratios of healthy normal controls and breast cancer survivor groups without lymphedema were very similar, with almost complete overlap in confidence intervals. However, those values were markedly different from the values assessed in the survivor group with lymphedema (p<0.001).

Conclusions: These findings suggest impedance ratios determined by single-frequency bioelectrical impedance can be used as markers for lymphedema in nonlaboratory settings when a standardized protocol is used.

FIG. 1.

Bias-corrected 99% confidence intervals of limb index ratios for breast cancer survivors and health control subjects by arm dominance. BCS, breast cancer survivor; BCSLe, breast cancer survivor with lymphedema; HCS, healthy control subject; LIRs, limb index ratio.