Attribution of symptoms to adjuvant endocrine therapy and association with adherence among older women with breast cancer: A qualitative study.

e24086 Background: Oral adjuvant endocrine therapy (AET) is an effective treatment for hormone receptor positive breast cancer to decrease recurrence and mortality. However, adherence to AET is poor, with 1/3 of patients not completing the recommended 5-year treatment course. Studies have shown that symptoms of the medication, such as joint pain, hot flashes, and fatigue, are associated with AET discontinuation. While previous studies have focused on symptoms post-AET initiation, preliminary evidence suggests that pre-AET symptoms may be an important predictor of early AET discontinuation. We used qualitative interviews to explore adherence to AET and patients’ attribution of symptoms to AET to provide context for a larger quantitative study on the role of patient-reported distress pre-AET as a predictor of AET discontinuation. Methods: Participants were recruited from the Froedtert/MCW Cancer Center registry, stratified by high (≥4) and low pre-AET Distress Thermometer scores and adherence to/discontinuation of AET. Semi-structured phone interviews followed an interview guide focused on constructs previously identified in the literature as having strong associations with AET adherence. Interviews were recorded and transcribed. A multidisciplinary team developed a codebook based on the conceptual framework describing AET discontinuation by AlOmeir et al. as well as other themes that emerged from the data. Results: Interviews were conducted with 31 participants; ages ranged from 57-86 years. Participants were diverse with respect to race/ethnicity (55% white, 26% Black, 13% Latina, and 6% other racial/ethnic groups). Participants who reported symptoms described hot flashes, joint pain, low appetite, memory loss, depression, and fatigue. We saw support for previous findings by AlOmeir et al in which ability to deal with symptoms affected the decision to continue AET. We uncovered additional nuance related to attribution of symptoms, in that some participants attributed their symptoms to a side effect of AET, while others attributed symptoms to other factors including older age, recent completion of other cancer treatments, and psychological burden associated with a cancer diagnosis and treatment. Those who did not attribute symptoms to AET focused on AET as necessary treatment to increase survival, while those who attributed symptoms to AET reported a more negative AET experience in general, with AET described as an additional burden after cancer. Conclusions: Symptom attribution rather than experience of specific symptoms may be a key factor leading to discontinuation of AET. Patient-reported symptoms and associated distress pre-AET may be a viable way to identify patients at high-risk for AET nonadherence, allowing for timely intervention. This will be quantitatively tested in a large sample.