Sleep Quality and its Associated Factors in Iranian Patients with Breast Cancer

Background: Sleep disturbances are common, but widely underdiagnosed in cancer patients. Thus, the aim of the present study was to evaluate sleep quality and its associated factors among women with breast cancer.Methods: This cross-sectional study was conducted on women with breast cancer referring to 2 outpatient clinics in Isfahan, Iran. Sleep quality [Pittsburgh Sleep Quality Index (PSQI)], severity of anxiety and depression [Hospital Anxiety and Depression Scale (HADS)], cancer symptoms [M.D. Anderson Symptom Inventory (MDASI‎)], and quality of life (QOL) [European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-‎Core 30 (EORTC QLQ-C30)] were assessed in the present study.Results: The study population consisted of 101 patients with mean age of 49.7 years and mean cancer duration of 2.3 years. The mean global PSQI score of patients was 8.5 and 80.2% had poor sleep quality. Factors associated with global PSQI score in univariate analyses were body mass index (BMI) (r = 0.445), severity of cancer symptoms (r = 0.580), anxiety (r = 0.363), and depression (r = 0.332). BMI and symptom severity were independently associated with poor sleep quality (standardized coefficient = 0.388 and 0.480, respectively). With regards to QOL, patients with poor sleep quality had lower physical and psychosocial functioning than good sleepers.Conclusion: Sleep disturbances are highly common in women with breast cancer in our society and significantly affect their QOL. Obesity, cancer symptoms, and psychological symptoms are important factors associated with and contributing to sleep problems in these patients. Cancer care programs must have a comprehensive approach, including sleep assessment and management, toward the treatment of these patients