Effects of a wearable technology-based physical activity intervention on sleep quality in breast cancer survivors: the ACTIVATE Trial.

INTRODUCTION: Physical activity interventions can improve sleep quality in breast cancer survivors. This paper examines the effects of the ACTIVATE Trial, a wearable-based physical activity intervention (Garmin Vivofit2® coupled with behavioral feedback, goal setting, and health coaching) on sleep outcomes. METHODS: Post-primary treatment, inactive, postmenopausal breast cancer survivors were recruited and randomized to primary intervention or waitlist. Wrist-worn actigraphy (sleep onset latency, SOL; total sleep time, TST; sleep efficiency, SE; wake after sleep onset, WASO; and number of awakenings, NWAKE) and questionnaire-derived sleep measures (Pittsburgh Sleep Quality Index) were assessed at baseline (T1), 12 weeks (end of primary intervention and start of waitlist intervention, T2), and at 24 weeks (T3). RESULTS: Eighty-three women (mean age = 62 years) were randomized; trial retention was 94% at T2 and 87% at T3. At T2, primary intervention participants had greater improvements in WASO (- 5.7 min, 95% CI - 11.7 to - 0.2) and NWAKE compared with the waitlist arm (- 2.0, 95% CI - 3.6 to - 0.4). At T3, within-group improvements were observed for SE (both groups), WASO (both groups), NWAKE (primary intervention group only), total PSQI score (primary intervention group), and sleep efficacy (primary intervention group). CONCLUSIONS: The intervention reduced actigraphy-measured sleep disturbances. Within-group analyses suggest that improvements in sleep quality are sustained over a longer duration, and there may be similar benefits from an abridged intervention (wearable device only). Actigraphy-measured effects appeared stronger in participants who were poor sleepers at study entry. IMPLICATIONS FOR CANCER SURVIVORS: Wearable technology can increase physical activity and improve sleep for breast cancer survivors.