Prevalence, clinical characteristics, and risk factors for insomnia in thecontext of breast cancer

Study Objectives: To estimate the prevalence of insomnia, describe clinical characteristics of sleep difficulties, assess the influence of cancer on t he insomnia course, and identify potential risk factors involved in the dev elopment of insomnia among women who had received radiotherapy for non meta static breast cancer. Design: A sample of 300 consecutive women who had been treated with radioth erapy for non metastatic breast cancer first completed an insomnia screenin g questionnaire. Participants who reported sleep difficulties were subseque ntly interviewed over the phone to evaluate further the nature, severity, d uration, and course of their insomnia. Setting: N/A Patients or Participants: N/A Interventions: N/A Measurements and Results: Nineteen percent (n=56) of the participants met d iagnostic criteria for an insomnia syndrome. In most cases (95%), insomnia was chronic. The onset of insomnia followed the breast cancer diagnosis in 33% of the patients and 58% of the patients reported that cancer either cau sed or aggravated their sleep difficulties. Factors associated with an incr eased risk for insomnia were sick leave, unemployment, widowhood, lumpectom y, chemotherapy, and a less severe cancer stage at diagnosis. Among women w ith insomnia symptoms, the risk to meet diagnostic criteria for an insomnia syndrome was higher in those who were separated and had a university degre e. Conclusions: Insomnia is a prevalent and often chronic problem in breast ca ncer patients. Although it is not always a direct consequence of cancer, pr e-existing sleep difficulties are often aggravated by cancer. It is therefo re important to better screen breast cancer patients with insomnia and offe r them an appropriate treatment.