The effect of treatment and coping on the quality of life in breast cancer patients: a moderated mediation model

Breast cancer involves complicated emotional processes. One of the factors that impacts the psychological symptoms and decreases QoL is the side effects of treatment. The purpose of this study is to explore the effect of the main medical treatment (chemotherapy or hormone therapy) on the three domains of quality of life. For this, coping strategies were considered as psychological variables that mediate the relationship based on high or low alexithymia as a moderating variable.

This study had a cross-sectional design. The participant sample comprised 129 women with breast cancer in early stage (I to III) (63 receiving chemotherapy and 66 hormone therapy) and were evaluated from September 2015 to September 2019. Physical, emotional and social functioning were measured by the Quality of Life Questionnaire for cancer patients (EORTC-QLQ-C30), coping strategies were measured by Mental Adjustment to Cancer Questionnaire (MAC) and alexithymia was evaluated by the Alexithymia Toronto Scale (TAS-20).

Treatment had a significant negative effect on physical domain in both patients receiving chemotherapy and hormone therapy. Moderated mediation analysis show that this relationship was significant when it was mediated by helplessness. Furthermore, this model is only significant when there are high levels of alexithymia. No significant effect direct was found on emotional and social functioning of quality of life.

Results confirmed that coping based on helplessness and stable emotional variables such as alexithymia can have an effect, mediator or moderator, respectively, in the decrease of the physical functionality of women with breast cancer. Our findings highlight the need to include psychological therapy to help patients alleviate their psychological state because it can affect their physical condition.