Approximately one quarter of all cancer patients suffer from chronic insomnia. This can present as difficulty falling asleep, waking throughout the night, or awakening early in the morning with the inability to fall back to sleep. Sleep disturbance and deprivation, as well as their associated pharmacological therapies, have side effects that can have a negative impact on an individual’s quality of life.
Starving the body of this vital repair period is detrimental cognitively, physically, and biologically. During sleep, the body undergoes a system of hormone release and inhibitions necessary for repair and information storage. Research has shown that, when left untreated, chronic insomnia leads to daytime fatigue and depressive behaviors, as well as impaired mood and reduced energy levels. Immune function is also compromised with the lack of sleep, leading to an increased risk of disease and infection.
Fatigue is highly prevalent in patients with cancer. Although cancer-related fatigue and cancer-related sleep disorders are distinct, a strong interrelationship exists between these symptoms. Studies that have assessed both sleep and fatigue in cancer survivors reveal a strong correlation between cancer-related fatigue and various sleep parameters, including poor sleep quality, nighttime awakening, restless sleep, a disrupted initiation and maintenance of sleep, and excessive daytime sleepiness. Current understanding of the possible link between cancer related fatigue and sleep disturbances suggests that interventions targeting disordered sleep could provide promising potential treatments.
Many treatment options have been explored to treat sleep disturbance and deprivation. In fact, Approximately 25%–50% of all prescriptions written for patients with cancer are for hypnotics. However, the vast majority contain side effects that interfere with quality of life, including residual next day effects, toxicity when combined with other sedating agents, risk of dependence, and rebound insomnia when stopped.
One possible non-pharmacologic treatment that may help offset the negative effects of sleep disturbance is exercise. The National Comprehensive Cancer Network (NCCN) asserts that moderate exercise has no harmful effects on cancer patients. In fact, decades of research support the use of exercise to improve mood, increase energy, increase strength, and build immunity. Further, patients who participate in regular exercise have reported up to 50% less fatigue during chemo-treatments. As such, the NCCN recommends approximately 150 minutes of moderate cardiovascular exercise each week along with 2 to 3 weekly sessions of strength training. In addition, regular stretching of major muscle groups will aid in mobility and reduce risk of injury.
Recently, at Maple Tree, we conducted a study on 253 patients who were undergoing chemotherapy and exercising as part of our program. On average, we found that patients who participated in prescribed, individualized exercise saw significant improvement to their sleep. These improvements are presented in the Table below. Given the emerging data that suggest cancer-related sleep disturbance is commonplace, and that it may be interrelated with symptoms of daytime fatigue, it follows that targeted treatment of either symptom may positively affect the other. This and other data point to physical exercise as an effective intervention for those with sleep disturbance and deprivation.
|Pre-score Average||Post-score Average||Percent Change|
|How long does it take you to fall asleep?||47.5 min||
|If you wake up one or more times during the night, how long are you awake in total?||41.4 min||22.12 min||90%*|
If your final wake-up time occurs before you intend to wake up, how much earlier is this?
|How many nights a week do you have problems with your sleep?||2.21||3.33||50.68%|
|How would you rate your sleep quality?||2.11 (Average)||3.41 (good)||61.61%*|
|Thinking about the last month, to what extent has poor sleep affected your mood, energy, or relationships?||2.42 (Somewhat)||3.81 (A little)||57.44%|
Thinking about the last month, to what extent has poor sleep affected your concentration, productivity, or ability to stay awake?
|1.72 (Very much)||3.01 (A little)||75%*|
|Thinking about the last month, to what extent has poor sleep troubled you in general?||2.78 (Somewhat)||3.71 (A little)||20.45%|