Abstract PO-001: Evaluating medication adherence and its predictors among breast cancer survivors on oral endocrine therapy in a large academic medical center

Abstract

Abstract Introduction: Adherence to oral endocrine therapy (OET) reduces recurrence risk for hormone receptor-positive breast cancer (HR+ BC). Refill data accessed through electronic health records (EHRs) may provide objective assessment of medication adherence. Our goal was to (1) determine feasibility of reviewing EHR to assess medication adherence, (2) evaluate 6-month OET adherence in HR+ BC patients, and (3) identify predictors of low adherence. Materials and methods: A single-center, retrospective study from May through December 2018 was conducted. Primary endpoint was adherence rate at 6-months. Chi-square and student’s t-test were used to compare adherent and non-adherent groups. Multivariable logistic regression models were used to assess predictors of adherence. Further, a subgroup analysis was further conducted among patients with stage 0 – III to assess the adherence in early-stage setting. Results: Of 492 patients, 338 patients were included in adherence analysis. Of 338 patients identified, 82% (n= 277) were adherent at 6 months. In the multivariable logistic model, race/ethnicity, type of endocrine therapy, and time on therapy were found to be significantly associated with adherence. Asian/Non-Hispanic and Caucasian/Hispanic patients were less likely to be adherent as compared to Caucasian/Non-Hispanics (Asian/Non-Hispanic OR 0.3; 95% CI 0.11-0.82, Caucasian/Hispanic OR 0.27; 95% CI 0.11-0.64). Patients on aromatase inhibitors were more likely to be adherent as compared to patients on tamoxifen (OR 2.06; 95% CI 1.02-4.14). Lastly, patients on OET for 3-5 years had lower adherence as compared to patients on OET for 2 years or less (OR 0.29; 95% CI 0.09-0.91). The subgroup analysis of patients with stage 0-III disease revealed similar findings that race/ethnicity and type of endocrine therapy were significant predictors of adherence. Conclusion: Accessing refill data through EHR was found to be feasible. Tamoxifen therapy, Asian/Non-Hispanic and Caucasian/Hispanic origin, and longer time on therapy predicted non-adherence in our patients. Citation Format: Anjana Mohan, Rutugandha Paranjpe, Grace Hwang, Carine Opsomer, Kelvin Lu, Uzo Abajue, Hanna Zaghloul, Susan Abughosh, Meghana Trivedi. Evaluating medication adherence and its predictors among breast cancer survivors on oral endocrine therapy in a large academic medical center [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-001.