The sleep disorders most likely to affect patients with cancer are insomnias and disorders of the sleep-wake cycle. Effects of tumor growth and cancer treatment that may cause sleep disturbances include:
Some drugs that help patients sleep (such as hypnotics and sedatives) should not be stopped suddenly without the advice of a doctor. Suddenly stopping these medicines may cause nervousness, seizures, and a change in REM sleep that increases dreaming, including nightmares. This change in REM sleep may be dangerous for patients with peptic ulcers or heart conditions.
Patients may have sleep interruptions due to treatment schedules, hospital routines, and roommates. Other factors affecting sleep during a hospital stay include noise, temperature, pain, anxiety, and the patient's age. Chronic sleep disturbances can cause irritability, inability to concentrate, depression, and anxiety. While in the hospital, sleep disorders may make it hard for the patient to continue with cancer therapy.