Wassermann, Johanna

Background Young age is a known factor associated with suboptimal adherence to endocrine therapy (ET) for adjuvant breast cancer (BC) treatment. This study was aimed at assessing nonadherent behaviors and associated factors among young women with early‐stage hormone receptor–positive BC. Methods As part of a multicenter, prospective cohort of women with a diagnosis of BC at or under the age of 40 years, participants were surveyed 30 months after their diagnosis about adherent behaviors. Among those who reported taking ET, adherence was measured with a 3‐item Likert‐type scale: Do you ever forget to take your ET? If you feel worse when you take your ET, do you stop taking it? Did you take your ET exactly as directed by your doctor over the last 3 months? Women reporting at least 1 nonadherent behavior were classified as nonadherers. Variables with a P value <.20 were included in a multivariable logistic model. Results Among 384 women, 194 (51%) were classified as nonadherers. Univariate factors that retained significance in the multivariable model included educational level (odds ratio [OR], 0.50 for high vs low; P = .04), level of social support according to the Medical Outcome Study Social Support Survey (OR, 0.98 per 1 point; P = .01), and confidence with the decision regarding ET measured on a 0 to 10 numerical scale (OR, 0.63 for high vs low; P = .04). Conclusions Findings from this study could help to identify young patients at higher risk for nonadherence. Interventions adapted to the level of education and aimed at reinforcing support and patients' confidence in their decision to take ET could improve adherence and associated outcomes in this population.

526 Background: Young age at diagnosis (dx) is a predictor of worse prognosis in patients (pts) with luminal breast cancer (BC). Poorer adherence to endocrine therapy (ET) among younger women may contribute to this disparity. Aim: To assess non-adherent behaviors and associated factors among young women with stage 1-3 hormone receptor (HR)+ BC taking ET. Methods: This study is a part of a multi-center, prospective cohort of pts with dx of BC at or under age 40. On a survey 30 months after dx, among pts reporting taking ET, adherence was measured using a 3-item Likert-type scale (Do you ever forget to take your ET? If you feel worse when you take your ET, do you stop taking it? Did you take your ET exactly as directed by your doctor?). Pts reporting any non-adherent behavior during the last 3 months were classified as non-adherers. Variables with a p-value <0.20 were included in a multivariate logistic model. Results: Among361 pts eligible for this analysis, 174 (48%) reported some non-adherent behaviors in the last 3 months; 56 (16%) moderate or greater non-adherent behaviors. None of the studied variables was associated with non-adherent behaviors (table). Conclusions: Non-adherent behaviors to ET are present in almost half of the young women with HR+ BC. Further analyses of explanatory factors and impact of non-adherence are required to understand and potentially improve this problem. [Table: see text]