Motivational Interviewing Counseling to Increase Endocrine Therapy Adherence in Diverse Patients

SIMPLE SUMMARY: Up to ten years of oral endocrine therapy can help prevent breast cancer recurrence and death in approximately 70% of patients diagnosed with hormone-receptor positive breast cancer for whom it is prescribed, but long-term adherence is low, particularly among Black women and those younger than age 50. Because the barriers to adherence are multifaceted, in this study, we designed and pilot-tested a flexible, evidence-based counseling intervention to help diverse women set breast health goals and identify and overcome the barriers to adherence. The results demonstrated a strong interest in the intervention, willingness to complete follow-up counseling sessions, high satisfaction with the intervention, and high adherence to endocrine therapy at twelve months, especially among Black participants, providing promising signals concerning the benefits of supportive behavioral counseling and motivating future work in this area. ABSTRACT: Background: Oral endocrine therapy (ET) is an inexpensive and effective therapy for hormone receptor-positive (HR+) breast cancer that prevents recurrence but relies upon long-term adherence for up to ten years. More than 80% of breast cancer patients have an HR+ phenotype and are candidates for ET, but approximately half discontinue or become non-adherent by five years. ET underuse is more prevalent in Black and young (<50 yrs) women, which may contribute to outcome disparities in these groups. The objective of this study was to evaluate the feasibility, acceptability, and utility of a patient-centered counseling intervention to enhance ET adherence, with a focus on the needs of Black and younger women. Methods: We conducted a single-arm pilot study of a twelve-month motivational interviewing (MI) intervention consisting of five MI counseling sessions, an interactive workbook, a resource guide, and an educational video developed and revised with iterative patient and clinician input. The eligible participants were >18 years old, English speaking, and with stage I–III HR+ breast cancer. Participants were recruited across a large academic medical center and four community sites. Feasibility and acceptability were assessed by measures of participant recruitment, retention, session participation, and patient-reported satisfaction. ET adherence at 12 months was assessed by self-report and medication event monitoring system (MEMS) caps using a continuous measure of the proportion of days covered (PDC) as well as a dichotomous measure of the optimal adherence, defined as >80% PDC. Results: Forty-two women initiated the intervention, of whom thirty-five participants (83%) completed outcome assessments at 12 months, including thirteen Black and twenty-two non-Black participants. The average participant age was 54.8 years (range: 25–73). Overall, 97% completed at least three MI sessions and 83% completed at least four sessions. Participant retention and satisfaction were high, particularly among Black women. Self-reported adherence at 12 months was 88% overall (100% in Black women and 81% in non-Black women). The majority of women also achieved 80% of days adherent using MEMS caps, with a greater adherence in Black women. Conclusions: This study demonstrates the feasibility, acceptability, and early promise of the effectiveness of an MI counseling-based intervention to promote ET adherence and prevent breast cancer recurrence in diverse populations.