Symptom Monitoring App Use Associated With Medication Adherence Among Woman Survivors of Breast Cancer on Adjuvant Endocrine Therapy.

Purpose: Oral adjuvant endocrine therapy (AET) reduces the risk of cancer recurrence and death for women with hormone receptor-positive (HR+) breast cancer. Because of adverse symptoms and socioecologic barriers, AET adherence rates are low. We conducted post hoc analyses of a randomized trial of a remote symptom and adherence monitoring app to evaluate characteristics associated with higher app use, satisfaction, and how app use was associated with AET adherence.

Methods: Patients prescribed AET were randomly assigned to receive one of three intervention conditions: app, app + feedback, or enhanced usual care. Baseline and 6-month follow-up surveys, app use, and pillbox-monitored AET adherence data for app and app + feedback participants were used. Logistic regression evaluated the association between sociodemographic/clinical characteristics and app utilization and satisfaction, and how app use was associated with AET adherence (>80%).

Results: Overall, 163 women with early-stage HR+ breast cancer were included; 35.0% had high app use (≥75% of weeks enrolled). No sociodemographic characteristics were associated with app use. Satisfaction with the app was higher among those who were younger (88.9% for age 31-49 years v 54.9% for age 65+ years, P < .001), identified as White (76.8% v 60.1% for Black, P = .045), had lower health literacy (85.4% v 68.2% with higher health literacy, P = .017), or were nonurban residents (85.7% v 68.6% for urban, P = .021). Most participants (90.3%) with high app use were AET-adherent compared with 66.8% for those with lower app use (P < .001).

Conclusion: Use of a remote monitoring app was similar across sociodemographic characteristics, and more frequent app use was associated with a higher likelihood of 6-month AET adherence. Encouraging women to monitor medication adherence and communicate adverse symptoms could improve AET adherence.