Abstract 159: Understanding Baseline Physical Activity In Cardiac Rehabilitation Enrollees Using Mobile Health Technologies

Background: Cardiac rehabilitation (CR) improves physical activity (PA) and reduces morbidity for patients with cardiovascular disease. We understand little of baseline PA as patients initiate CR, particularly when outside of CR. We used mobile health (mHealth) technology to understand baseline PA of patients initiating CR within a clinical trial to potentially inform personalized care.

Methods: The Virtual AppLication-Supported Environment to INcrease Exercise During Cardiac Rehabilitation Study (VALENTINE) Study is a prospective, randomized-controlled, remotely administered trial designed to evaluate an mHealth intervention to supplement CR for low- and moderate-risk patients. Participants are randomized after 2 CR sessions; all receive a smartwatch and usual care. Remotely administered baseline PA outcomes include 6-minute walk distance, step count, and exercise minutes. Baseline PA was assessed for 7-days after study enrollment for compliant days, defined by >8 hours of watch wear/day. Multivariable linear regression identified features associated with baseline PA.

Results: From October 19, 2020 to January 31, 2022, 180 participants enrolled. Participants are mostly White [156 (86.7%)]; 59 (32.8%) are female and 69 (38.3%) are > 65 years old. Most enrolled in CR after coronary revascularization [114 (64.4%)] or valve intervention [40 (22.2%)]. Comorbidities include hypertension (65.0%), valve disease (35.6%), and heart failure (17.8%). Participants were compliant for 91.4% of days with 15.3 (4.0) hours/compliant day. Baseline PA included 6-minute walk distance of 491.8 (147.8) meters, daily step count of 6818 (3386), and exercise minutes of 36.0 (33.4). Substantial variation in baseline PA assessed by 6-minute walk distance was noted across age and gender but not CR indication.

Conclusions: Understanding baseline PA as participants enroll in CR may be useful in personalizing CR programs at initiation and designing mHealth interventions.