Concurrent factors associated with adherence to adjuvant endocrine therapy among women with non-metastatic breast cancer

Adjuvant endocrine therapy (AET) reduces breast cancer morbidity and mortality, yet women often report suboptimal adherence. Though correlates of AET adherence are well-documented, few studies examine the relative importance of multi-level factors associated with adherence. The aim of this study was to identify factors most strongly associated with AET adherence in women with breast cancer. Between 10/2019 and 6/2021, women (N = 100) with non-metastatic, hormone receptor-positive breast cancer, taking AET who reported AET-related distress enrolled into a clinical trial. Participants completed baseline measures, including the Medication Adherence Rating Scale-5, sociodemographics, and validated measures of anxiety, depression, medication-taking self-efficacy, social support, and treatment satisfaction. We created a latent factor and tested associations between sociodemographic, medical, and psychosocial characteristics and adherence. Associated predictors (p < .10) were entered into a structural model, which was corroborated via multivariate regression modeling. A four-indicator latent adherence factor demonstrated good model fit. Participants (Mage = 56.1 years, 91