# Factors Influencing Adherence to Adjuvant Endocrine Therapy After Breast Cancer Surgery

## TL;DR

This study explores why some women with breast cancer do not follow hormone therapy after surgery, finding that life satisfaction and side effects play a role.

## Contribution

The study identifies specific demographic and psychological factors influencing adherence to adjuvant endocrine therapy in breast cancer patients.

## Key findings

- Younger women and those who felt healthier were less likely to adhere to therapy.
- Satisfaction with work and family life improved adherence to treatment.
- Adherent women reported more side effects, including musculoskeletal and sexual issues.

## Abstract

Women with newly diagnosed hormone receptor‐positive breast cancer are offered adjuvant endocrine therapy (AET). Despite the survival benefits of the therapy, a significant proportion of breast cancer patients do not adhere to the anti‐hormonal medication.

The purpose of this study was to analyse demographic, social, psychological and treatment‐related factors influencing whether women diagnosed with early‐stage breast cancer were adherent to offered therapy.

This was a long‐term retrospective, medical record study, supplemented with a questionnaire, including 81 women. Data from the Swedish Prescribed Drug Register were used to examine adherence. The women were followed for 5 years of offered AET.

Out of 81 women, 67 (83%) were adherent (hade taken out 80% or more of the recommended dose), 10 (12%) were Partially Adherent and 4 (5%) never accepted AET. At baseline, the Never‐Adherent group members were younger, more often considered themselves healthy and seemed much more satisfied with their lives. Baseline factors that positively affected adherence were satisfaction with the vocational situation (p = 0.023) and satisfaction with family life (p = 0.040). Cumulative musculoskeletal side effects were more frequently reported among women in the Adherent group than Partially Adherent women, after both 12 and 60 months (p = 0.018 and p = 0.011, respectively). There was also a significant difference in reported cumulative psychological side effects (p = 0.049) in disfavour of the Adherent group. Moreover, according to the questionnaire where the women retrospectively were asked which side effects, they experienced during the treatment period; sexual desire was significantly lower in the Adherent group (p = 0.0402) than in the Partially Adherent group.

It is important to consider a woman's life situation, to support those who otherwise would not be able to complete AET and to help all women relieve side effects during AET. It should be investigated why some women did not start the recommended therapy.