Changes in Physical Activity, Functional Capacity, and Cardiac Function during Breast Cancer Therapy

Authors: Bellissimo MP, Canada JM, Jordan JH, Ladd AC, Heiston EM, Brubaker P, Mihalko SL, Reding K, D"Agostino Jr R, O"Connell N, Hackney MH, Weaver KE, Lesser GJ, Avis NE, Hundley WG

Category: Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2022

Abstract Body:
Purpose: Functional capacity and cardiac function can decline during breast cancer (BC) therapy. In non-cancer populations, higher physical activity (PA) is associated with better physical function and cardiac health. This study compared baseline PA, functional capacity, and cardiac function between women with and without BC and tested if greater PA participation was related to higher functional capacity and/or better heart function after three months of BC therapy.Methods: Data was collected in 104 women without BC (82% Caucasian, baseline only) and 110 women with stage I-III BC (82% Caucasian) before therapy and after three months of treatment. Participants self-reported PA and underwent six-minute walk distance (6MWD) testing to measure functional capacity and cardiovascular magnetic resonance to assess left ventricular ejection fraction (LVEF). Analyses were adjusted for age, race, body mass index (BMI), and medication use.Results: The BC group was older (56.2 ± 10.7 vs 52.1 ± 14.7 yrs, P=0.02) with a higher average BMI than the non-cancer group (30.3 ± 6.8 vs 27.7 ± 6.2 kg/m2, P<0.01). Pre-treatment, BC participants reported lower PA scores (27.9 ± 2.8 vs 34.9 ± 2.8, P=0.04) with similar 6MWD and LVEF relative to those without cancer (485 ± 11 vs 496 ± 11 m, P=0.4 and 59.7 ± 0.7 vs 58.9 ± 0.8%, P=0.37, respectively). After three months of BC therapy, declines were observed for PA scores (27.9 ± 2.8 vs 18.3 ± 2.5, P=0.02), 6MWD (485 ± 11 vs 428 ± 10 m, P<0.001), and LVEF (59.7 ± 0.7 vs 56.1 ± 0.7%, P<0.001). Compared to BC participants who reported no PA at three months (n=24, 22%), BC women who reported any PA (n=78, 86%) had higher 6MWD (442 ± 11 vs 389 ± 17 m, P=0.006) but similar LVEF (56.5 ± 0.9 vs 55.3 ± 1.5%, p=0.5). Women who reported any PA were less likely to exhibit an LVEF below normal (<50%) or decline in LVEF of ≥10 points compared to inactive women (BMI-adjusted, OR [95% CI]: 0.27 [0.09, 0.85]).Conclusions: These preliminary results indicate that self-reported PA, LVEF and 6MWD decline in the first three months of BC treatment, but PA participation during BC treatment may mitigate declines in functional capacity and cardiac function. Further research is needed to identify barriers and facilitators of PA participation during BC therapy.

Keywords: functional capacity, behavior, physical activity, cardiac function, breast cancer