Sleep and endocrine therapy in breast cancer.

Sleep disturbances and insomnia are common among breast cancer survivors, and can have a significant effect on quality of life and numerous other significant outcomes. Among risks for sleep disturbance is the introduction of anti-estrogen endocrine therapies. The possible contributing factors to sleep disturbance in endocrine therapy are complex, and include pre-existing sleep disorders, the effects of chemotherapy and other treatments, and concurrent symptoms such as hot flashes. In addition, sleep disturbance in menopause, the natural downregulation of reproductive hormones in older age, is a common occurrence, and can offer a model for understanding the high prevalence of sleep problems in breast cancer survivors on endocrine therapy, as well as suggesting possible treatments such as behavioral interventions and pharmaceuticals. Altogether, significantly more research is needed to better understand and address sleep disturbance in breast cancer survivors on endocrine therapy in order to support quality of life and treatment adherence.