Sleep disturbances are associated with cancer stage, being more common among patients with advanced disease, and can impact patient well-being in several domains, including anxiety, physical weakness (asthenia), and pain management, according to a new study of patients undergoing radiation therapy. The role of radiation therapy in sleep disturbance is poorly understood, but cranial irradiation is a well-established risk factor for sleep problems, including somnolence syndrome. Oncology nurses and radiation oncology team members should ask patients if they are experiencing sleep problems, and patients for whom sleep disorders are suspected should be referred for sleep medicine studies, diagnosis, and treatment.
Sleep disturbances are common among patients with medical conditions,1-9 and patients with cancer are at least twice as likely to suffer insomnia as the general population.4,5 Up to 88% of cancer patients experience sleep problems such as insomnia, hypersomnia, and sleep apnea, compared with 15% of the general population (Table 1).4,5 Such sleep disturbances can have an important impact on patients’ well-being in several domains, including memory and cognitive function, immune function, depression, anxiety, and quality of waking-life.1-5
TABLE 1. Sleep Disorders in Patients with Cancer5
|Circadian rhythm disorders
Disorders of the sleep-wake cycle
Disorders of excessive sleep
Disorders initiating or maintaining sleep state
Dysfunctions associated with sleep, sleep stages, or partial arousals from sleep
Sleep-related breathing disorders
Extreme daytime drowsiness and hypersomnia, frequently seen in adult and pediatric patients with acute lymphocytic leukemia
Several factors appear associated with sleep disturbances in cancer such as circulating hormone levels, pain, tumor-associated symptoms (such as pain, fever, and shortness of breath), seizure disorders, chemotherapy agents, alcohol consumption, and use of opioids and other sedatives or hypnotics.1-5 Sleep disorders may also predate cancer diagnosis; however, few studies have focused on the effects of preexisting sleep dysfunctions on cancer and its treatment and outcomes.
The exact nature of the relationships between postdiagnosis sleep problems and associated factors, including the molecular pathways involved, in patients with cancer remain poorly understood.