Remotely-delivered Cardio-oncology Rehabilitation for Breast Cancer Patients (REMOTE-COR-B): A single arm, feasibility trial (Preprint)

BACKGROUND Breast cancer survivors are at increased risk of cardiovascular disease due to shared risk factors and the cardiotoxic effects of some cancer treatments. Exercise rehabilitation may reduce cardiovascular risk, but most evidence comes from centre-based programs involving in-person supervision. Smartphone-based telerehabilitation may offer a scalable alternative that provides real-time supervision while improving access to home-based rehabilitation. OBJECTIVE This study aimed to evaluate the feasibility of REMOTE-COR-B, a smartphone-based telerehabilitation program for women with breast cancer at increased cardiovascular risk. Secondary aims were to assess safety, satisfaction, usability, trial feasibility, and preliminary effects on physical activity, fitness, fatigue, and quality of life. METHODS Women with stage I-III breast cancer at risk of cardiovascular disease participated in an 8-week, smartphone-based exercise program, involving remotely-delivered exercise supervision and behaviour change support. The primary feasibility outcome was adherence, defined as completion ≥70 % of monitored sessions. Secondary outcomes included recruitment, safety, satisfaction, usability, and effect outcomes. Assessments occurred at baseline, post-intervention and five-months post-baseline. Objective fitness was assessed in a subsample. RESULTS Recruitment was slower than expected. Of 21 participants recruited, 20 commenced the intervention and 17 completed it. Weekly sessions were completed by 94% of participants, and 47% met the adherence target. No serious adverse events occurred. Satisfaction was high (mean Client Satisfaction Questionnaire score = 24.2, SD = 3.8), while usability was below the acceptable threshold (mean System Usability Scale score = 63.0, SD = 21.6). Post-intervention, participants reported significant improvements in physical activity (mean change = 7.5 units on the Godin-Shepard Leisure-Time Physical Activity Questionnaire, 95% CI 0.7,14.3) and clinically meaningful improvements in cardiorespiratory fitness (mean increase incremental shuttle walk test = 64 m, 95% CI 6.3 to 122.3; n = 7). Positive trends were observed for fatigue and breast cancer-specific quality of life. CONCLUSIONS REMOTE-COR-B was feasible, safe, and acceptable, with promising early benefits. Recruitment protocols, session attendance expectations, and usability issues need consideration before a larger controlled trial. CLINICALTRIAL Australian New Zealand Clinical Trials Registry Study ID number: ACTRN12621001557820. Prospectively registered 09 August 2021. INTERNATIONAL REGISTERED REPORT RR2-10.2196/53301