Sleep disturbances and cancer: why sleep matters
Sleep disturbances and cancer: there is a relationship between them. Sleep disturbances affect between 30 and 75 % of newly diagnosed or recently treated cancer patients , a rate that has been reported as double as that of the general population . Surveys have suggested that sleep complaints from cancer patients consisted of difficulties in falling and staying asleep, with frequent and prolonged nighttime awakenings. Patients reported these complaints both before and during treatment .
Sleep disturbances have been shown to decrease quality of life, decrease work productivity, increase utilization of health care resources, decrease mental health, and serve as a predictor of other complications in cancer patients [4, 5, 6].
Sleep disturbances and cancer: why sleep matters for cancer patients
Studies covering sleep disturbances and cancer have shown that bad sleep habits may increase the risk of cancer recurrence. During sleep, our brain produces the hormone called melatonin. Melatonin is a very potent stimulant for our immune system and has oncostatic properties, which means it may help reduce the risk of cancer progression. Furthermore, having trouble sleeping, especially when it is chronic, alters the balance of cortisol and melatonin. These two hormones may influence the behavior of cancer cells .
“Patients need as much vitality and energy as possible to fight their cancer. Sleep allows the body to relax and recoup. Without sleep, the body becomes even more stressed, which can interfere with its ability to fight cancer.” says Dr. Altshuler, head physician of the Sleep Lab at Cancer Treatment Centers of America® (CTCA) in Tulsa .
Moreover, when patients get enough rest they are less likely to be depressed, and there is some evidence showing that depression may be associated with an increased risk of recurrence. A study submitted at the 2013 Annual Meeting of the American Society of Clinical Oncology reported that depressed women with breast cancer had a 50 % greater chance of recurrence than women with breast cancer who were not depressed.
What are the primary reasons for cancer patients to experience sleep disturbance?
Sleep disturbances and cancer are often linked to emotional distress. Emotional distress is usually the main reason cancer patients do not sleep well. Uncertainty and worries about the future, which include anxiety, depression, and overall stress related to familial and financial concerns, provoke stress that can hamper sleep.
The manifestations of the cancer itself or treatment side effects, including radiation and chemotherapy, are both known to lead to sleep disturbances, and may contribute to sleep problems; so does pain, a symptom often observed in cancer patients. Regarding the onset of sleep disturbances, studies have shown that it might already be present before the beginning of a treatment.
Diagnosing sleep disorders
Sleep disturbances are common among cancer patients for many reasons. Sleep problems can occur at any stage during treatment for cancer and in some patients, sleep disturbance may be the main symptom that leads to the diagnosis of certain types of cancer. Poor sleep impairs quality of life in people with cancer, but most do not specifically complain about sleep problems unless they are explicitly asked. Insomnia and fatigue are the most common sleep disorders in this cohort, although primary sleep disorders, including obstructive sleep apnea and restless legs syndrome, which are common in the general population, have not been carefully studied in oncology setting despite significant impairment of their quality of life .
If sleep is interrupted or does not last long enough, the phases of sleep are not completed and the brain cannot finish all the tasks that help restore the body and mind.
Sleep problems are significant among cancer patients prior to undergoing radiotherapy, and were found to be associated with cancer progression, prior treatments and other psychosomatic symptoms, e.g., anxiety. Sleep problems within this context must be explored to provide adequate guidelines to palliate their effects on quality of life .
Sleep disturbances and cancer: dealing with sleep disorders
If you have chronic sleep problems, a good night’s sleep can seem out of reach. Sleep problems that persist for a long time may increase the risk of anxiety and/or depression. There are, however, several therapies to help improve your sleep. In many cases, cancer patients can benefit from working with a psychologist or sleep specialist. Cognitive behavioral therapy, such as relaxation techniques, have shown promising results, next to mindfulness and/or setting up a strict bedtime and wake-up time. Please consult your clinician and/or medical specialist before starting any specific therapy.
- Ancoli-Israel S, Moore P, Jones V. The relationship between fatigue and sleep in cancer patients: a review. Eur J Cancer Care (Engl) 2001;10:245–255.
- Berger AM, Parker KP, Young-McCaughan S, et al. Sleep wake disturbances in people with cancer and their caregivers: state of the science.Oncol Nurs Forum.2005;32:E98–E126. A comprehensive review.[PubMed]
- Cimprich B. Pretreatment symptom distress in women newly diagnosed with breast cancer.Cancer Nurs.1999;22:185–194.[PubMed]
- Cancer Nurs. 2015 Jan-Feb;38(1):60-70. doi: 10.1097/NCC.0000000000000128.
- Akman, T., Yavuzsen, T., Sevgen, Z., Ellidokuz, H. and Yilmaz, A. U. (2015), Evaluation of sleep disorders in cancer patients based on Pittsburgh Sleep Quality Index. European Journal of Cancer Care. doi: 10.1111/ecc.12296
- Rumble ME, Keefe FJ, Edinger JD, Affleck G, Marcom PK, Shaw HS. Contribution of Cancer Symptoms, Dysfunctional Sleep Related Thoughts, and Sleep Inhibitory Behaviors to the Insomnia Process in Breast Cancer Survivors: A Daily Process Analysis. Sleep. 2010;33(11):1501-1509.
- De Bella et al (2013), Melatonin Anticancer Effects: Review, Int J Mol Sci. 2013 Feb; 14(2): 2410–2430.
- J Community Support Oncol.2015 Apr;13(4):148-55. doi: 10.12788/jcso.0126. / http://www.ncbi.nlm.nih.gov/pubmed/25978413
- Eur J Oncol Nurs.2015 Mar 14. pii: S1462-3889(15)00021-6. doi: 10.1016/j.ejon.2014.12.008. / http://www.ncbi.nlm.nih.gov/pubmed/25782721
- US National Library of Medicine. National Institutes for Health. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2951736/
- Cancer Treatment Centers America: http://www.cancercenter.com/southwestern/medical-departments/sleep-lab/
- National Cancer Institute: http://www.cancer.gov/about-cancer/treatment/side-effects/sleep-disorders-pdq