Effects of a Physical Activity mHealth Intervention (Fit2Thrive) on WCRF/AICR Cancer Prevention Score among Breast Cancer Survivors: A Secondary Data Analysis.

BACKGROUND

Interventions targeting moderate-to-vigorous physical activity (MVPA) may be a catalyst for improving other lifestyle behaviors in breast cancer survivors (BCS). We examined whether Fit2Thrive, mHeath MVPA intervention, influenced adherence to cancer prevention recommendations.

METHODS

BCS (N=269, age (M=52.9;SD=9.9) received a 12-week mHealth MVPA intervention and were randomized to "on" or "off" level of 5 intervention components. The World Cancer Research Fund International/American Institute for Cancer Research (WCRF/AICR) score was calculated (0= high cancer risk, 6=low cancer risk) based on cancer prevention recommendations: sugar-sweetened beverages, fast food, fruit/vegetable, body mass index, alcohol consumption, and MVPA (baseline, 12- and 24-weeks). Mixed-effects models examined changes in WCRF/AICR score and each risk factor and the effects of each intervention component (telephone support calls, Fitbit buddy, tailored text messages, deluxe app, online gym) level on the WCRF/AICR score.

RESULTS

The WCRF/AICR total score significantly improved at 12- and 24-weeks (p's<.001). MVPA improved at 12- and 24-weeks (p's<.001). Fruit and vegetable consumption improved at 12-weeks (p=0.01). No changes in other risk factors were observed.

CONCLUSIONS

Participation in a mHealth MVPA intervention may influence cancer risk in BCS and have effects on certain untargeted behaviors (fruit and vegetable consumption), but not other risk factors (sugar-sweetened beverages, fast food, body mass index, alcohol consumption). Future work should explore how to maximize these effects and determine if resource-efficient dietary intervention components improve cancer outcomes.

IMPACT

Understanding the impact of a mHealth MVPA intervention on untargeted dietary behaviors may guide the development of scalable interventions targeting lifestyle behaviors.