Patients suffering from chronic pain often find their problems are compounded by insomnia and sleeping disorders. Among those with chronic pain, an estimated 50% to 80% have ongoing sleep difficulties.1
Back pain is the most common type of chronic pain problem, and is the most common medical disorder in industrialized societies. Back pain is also the chief cause of disability among those younger than 45. Not surprisingly, more than half of individuals with back pain frequently report significant interference with sleep.2
Research has demonstrated that disrupted sleep will, in turn, exacerbate chronic back pain.3 A lack of restorative sleep also hampers the body’s immune response and can affect cognitive function. Thus, a vicious cycle develops in which the back pain disrupts one's sleep, and difficulty sleeping makes the pain worse, which in turn makes sleeping more difficult, etc.
Pain Is the Top Cause of Insomnia
The term "insomnia" includes all types of sleeping problems, such as difficulty falling asleep, difficulty staying asleep, and waking up earlier than desired. Of all medical conditions, pain is the number one cause of insomnia.
For people with chronic pain, trouble falling asleep is one of the most prevalent types of sleep disruption, but waking up during the night and waking earlier than desired are also frequent problems. In addition, many patients with chronic back pain problems do not feel refreshed in the morning when they awaken, a sleeping problem termed “non-restorative sleep.”
Trouble Falling Asleep
Chronic pain can impact sleep in a number of ways. To understand how a pain problem can make it difficult to fall asleep, it is helpful to think about the process associated with going to sleep for the night.
In getting ready for bed, it is common to eliminate all distractions or other influences in an effort to relax and fall asleep. This may include quieting the room, turning off the lights, eliminating any other noises, trying to get comfortable, and beginning to try to fall asleep.
However, this quieting of one's environment can cause problems for the chronic back pain sufferer, since the only thing left for the brain to focus on is the pain. Patients will often report that one of their primary pain management tools during the day is to distract themselves from their chronic back pain by staying busy with other tasks (e.g., reading, watching television, engaging in hobbies or crafts, working, interacting with others, etc.).
When trying to fall asleep, there are no distractions except for the pain, and the perception of pain can actually increase. The longer falling asleep is delayed, the more stressful the situation becomes.
Problems Staying Asleep
Many chronic pain patients also report awakening frequently during the night. Research has demonstrated that individuals experiencing chronic lower back pain may experience several intense "microarousals" (a change in sleep state to a lighter stage of sleep) per hour of sleep, which lead to awakenings. Thus, the chronic pain problem can be a significant intrusion into a night's sleep and disruptive to the normal stages of sleep.
This problem is often the cause of non-restorative sleep. Individuals with chronic pain often experience less deep sleep, more awakenings during the night, as well as less efficient sleep. Thus, the quality of sleep is often light and unrefreshing.
This non-restorative sleep pattern can then cause diminished energy, depressed mood, fatigue, and worse pain during the day.