Abstract PO4-11-09: Feasibility of physical activity behaviour change for women living with metastatic breast cancer, a randomised controlled trial
Authors: Liu Mark , Kilbreath Sharon , Dylke Elizabeth , Yee Jasmine , Beith Jane 
Published: May 2024

Abstract
Background
Physical activity benefits women living with metastatic breast cancer by improving outcomes such as physical function, health-related quality of life and fatigue. These findings have been reported within well-resourced trials that involve exercise equipment and supervision. Home or community-based settings, however, may be preferable and more accessible. This trial evaluated the feasibility of a remotely delivered behaviour change intervention for increasing physical activity for women living with metastatic breast cancer, and evaluated the program’s efficacy.
Methods
A 12-week randomised controlled trial was conducted in which 20 women living with metastatic breast cancer were recruited from a metropolitan outpatient cancer clinic. Inclusion criteria were over 18 years old, English speaking, ambulatory, and not regularly active at time of recruitment. Participants were randomised 1:1 to an intervention or attention control group. Both groups received a recommendation for 150 minutes of physical activity, a wrist-worn activity monitor, a physical activity diary, and nine phone or video call sessions (six weekly, three fortnightly). The intervention group received individualised behaviour change advice on topics such as physical activity benefits, motivation, barriers and social support; the attention control group received a recurring symptom questionnaire and no behavioural advice. Feasibility outcomes included recruitment, dropout and session adherence rates, and acceptability of methods was evaluated with an interview at trial completion. Baseline and 12-week outcomes included: i) physical activity minutes measured with a 5-day Actigraph wear, ii) 6-minute walk distance, iii) 30-second sit-to-stands, iv) questionnaires for self-reported physical activity, health-related quality of life, fatigue, behavioural factors (stage of change, self-efficacy, decisional balance, processes of change, social support), and patient-specific function. Questionnaires were measured again at 18 weeks.
Results
Recruitment, baseline measures and within-trial sessions are completed; 12 and 18-week measures will conclude late August. Thirty-two women were approached to enrol the target sample of 20, with exclusion reasons being disinterest (n=5), health problems (n=4), loss of contact (n=2) and already physically active (n=1). Median age was 62 years (IQR: 60-69), and median time since metastatic diagnosis was 4 years (IQR: 1-5). Twelve women had bone metastases, and ten had a musculoskeletal comorbidity. Session delivery through video or phone calls were equally preferred (n=10 each). Participants completed 84% of the sessions, with reasons for missed sessions consisting of forgetting (55%), feeling unwell (24%), IT problems (7%), holiday (7%), and work commitments (7%). Median session duration for the intervention group was 23 minutes (IQR: 20-28), and control group was 17 minutes (IQR: 14-21). The preferred type of physical activity was predominantly walking, and no adverse events were reported. Four women dropped out after loss of contact. Compared to age-matched normative values, baseline outcomes varied: actigraphy-measured physical activity was low (median: 68 minutes/day, IQR: 45-88), self-reported physical activity was high (median: 289 MET-minutes/day, IQR: 52-728), 6-minute walk distance was equal (median: 529m, IQR: 416-579), 30-second sit-to-stands were low (median: 11, IQR: 8-14), health-related quality of life was high (median: 80, IQR: 70-100), and fatigue was equal (median: 30, IQR 20-40).
Conclusions
Women living with metastatic breast cancer were generally receptive of the trial, and recruitment, dropout and session adherence rates were positive. The women who dropped out were more physically active, physically functional and/or rated higher on the questionnaires, indicating that the trial may be more suited to those with limited physical activity experience.
Citation Format: Mark Liu, Sharon Kilbreath, Elizabeth Dylke, Jasmine Yee, Jane Beith. Feasibility of physical activity behaviour change for women living with metastatic breast cancer, a randomised controlled trial [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-11-09.