Persistent Cancer-Related Fatigue Predicts Static And Dynamic Balance in Women With A History of Breast Cancer

Abstract

<h3>Research Objectives</h3> To examine the contributions of persistent cancer-related fatigue (CRF) and chemotherapy-induced peripheral neuropathy (CIPN) to pre- and post-exertional static and dynamic balance among women with a history of breast cancer. <h3>Design</h3> Secondary analysis of cross-sectional data. <h3>Setting</h3> Outpatient private university laboratory <h3>Participants</h3> 43 women who had completed chemotherapy for stage I-III breast cancer 3.5 ± 2.1 years prior to study involvement were recruited from a breast cancer center in a large urban hospital. <h3>Interventions</h3> Repeated sit-to-stands, representing a moderate-intensity lower extremity exercise, were performed to volitional exhaustion or 15-minutes. <h3>Main Outcome Measures</h3> Postural sway was measured via force plate in the medial-lateral (ML) and anterior-posterior (AP) planes in static standing and during the unsupported rising phase of an instrumented sit-to-stand (ISTS) before and after exercise. <h3>Results</h3> CRF was a statistically significant predictor of static standing postural sway in the AP plane before, p = 0.04, and after exercise, p = 0.02, with greater CRF predicting greater AP sway. CRF accounted for greater variance in pre- and post-sway compared to CIPN which was not a significant predictor. CRF was also a statistically significant predictor of post-exertional rising phase sway in the AP plane, p = 0.01, with greater CRF predicting smaller, more conservative anterior weight shifting during the ISTS. CIPN was not a significant predictor of rising phase sway and accounted for less than half of the variance as CRF. <h3>Conclusions</h3> CRF, even several years following exposure to chemotherapy, may distinctly influence balance independent of CIPN symptoms. Individuals with CRF should be assessed for instability regardless of CIPN status and should be educated regarding potential imbalance following exercise or other fatiguing tasks. Clinicians should consider the order of an objective examination of an individual with CRF, as postural stability may vary based on whether it is tested before or after physically fatiguing tasks. CRF warrants greater consideration in clinical practice and research as a mechanism of postural instability. <h3>Author(s) Disclosures</h3> No conflicts of interest. This study was supported by a grant from the National Institute on Aging.