Identifying the predictors of adherence to oral endocrine therapy in racial/ethnic minority patients with low socioeconomic status.

Background Adherence to oral endocrine therapy (OET) is crucial in ensuring its maximum benefit in prevention and treatment of hormone receptor-positive (HR+) breast cancer (BC) in patients. Medication use behavior is suboptimal especially in racial/ethnic minorities of lower socioeconomic status (SES). We aimed to assess the OET adherence and its predictors in racial/ethnic minority patients of lower SES. Aim We aimed to assess the OET adherence and determine the predictors of OET nonadherence in racial/ethnic minority patients of lower SES. Method A retrospective study was conducted at the Harris Health System in Houston, Texas. Since the study period included the COVID-19 pandemic, data was collected during the 6 months prior and 6 months after the start of the pandemic. The adherence was assessed using the prescription refill data using the proportion of days covered. Multivariable logistic regression model was used to identify predictors of nonadherence. Eighteen years or older patients on appropriate doses of OET for prevention or treatment of BC were included. Result In 258 patients, the adherence was significantly lower during the pandemic (44%) compared to before the pandemic (57%). The predictors of OET nonadherence before the pandemic were Black/African American, obesity/extreme obesity, prevention setting, tamoxifen therapy, and 4 or more years on OET. During the pandemic, prevention setting and those not using home delivery were more likely to be nonadherent. Conclusion Racial/ethnic minority patients of lower SES, especially African Americans and those using OET for prevention of BC, require individualized interventions to improve adherence.