Predictors of medication adherence to endocrine therapy in women with breast cancer: An analysis based on Temporal self-regulation theory

Purpose Some patients with breast cancer show low adherence to endocrine therapy (ETs). The Temporal self-regulation theory (TST) can explain adherence to medication behavior. Using TST to demonstrate medication adherence in patients with cancer has not been previously investigated. This study aimed to describe the behavior of ET adherence in women with breast cancer and examine the factors affecting health behaviors by applying the TST model. Methods A cross-sectional study design was used to collect data on connectedness beliefs, temporal valuations, intentions, self-regulatory capacity, behavioral prepotency, and ET adherence among 220 women with breast cancer. Results Approximately one in seven women with breast cancer had low ET adherence. Under the guidance of the TST, it was found that factors directly influencing ET adherence included connectedness beliefs-barriers, intention, self-regulatory capacity, and behavioral prepotency. Both self-regulatory capacity and behavioral prepotency partially mediated the relationship between intention and medication adherence. Benefits and barriers to connectedness beliefs indirectly affected medication adherence through intentions. There were no significant moderators. Conclusions This finding indicated that connectedness beliefs, intention, self-regulatory capacity, and behavioral prepotency are important predictors of ET adherence. This can be considered the direction of future interventions for patients with breast cancer to promote ET adherence.