Insomnia in cancer patients: a systematic literature review

PURPOSE Cancer patients often experience insomnia which can remain undetected in clinical practice, exacerbating mood disturbance, fatigue, and immunosuppression and impacting quality of life (QoL) and treatment outcomes. This review aimed to identify risk factors for insomnia and susceptible populations among cancer patients, and to quantify the impact of insomnia on QoL. METHODS This systematic review utilized pre-defined search criteria to identify studies related to the epidemiology and humanistic impact of insomnia in adult (≥ 18 years) cancer patients and their caregivers in the Medline and EMBASE databases. RESULTS Search terms identified 1,371 publications; 82 of these met the inclusion criteria. The studies showed that insomnia was prevalent throughout patients’ cancer journeys. Insomnia often preceded the diagnosis of cancer by months and persisted for several years after treatment. Breast cancer was the tumor type with the most reports of insomnia. Insomnia substantially impacted patients’ QoL. Subgroups who might benefit most from treatment for insomnia were those receiving chemotherapy and those with comorbid psychological symptoms such as anxiety and depression. For many tumor types and patient populations there were few or no studies of insomnia. CONCLUSIONS The medical literature reports that insomnia is highly prevalent in cancer patients, and significantly affects their QoL. Detecting and treating insomnia should be an element in the comprehensive care of cancer patients, to improve their physical health, and emotional well-being and QoL.