We talk about sleep a great deal. We don’t seem to get enough, and when we do, we still don’t feel rested. But what really is dysfunctional sleep?
Dysfunctional sleep is loss of sleep and ineffective sleep patterns. This problem can cause agitation, phobia, sleep deprivation psychosis, headaches, cognitive deficit, problems with gait, weight problems, and it can affect our mental, physical, emotional, and spiritual health and weaken our immune response. Though sleep dysfunction can be part of any chronic pain condition, it is especially prevalent in fibromyalgia (FM) and myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS). Both disorders affect multiple body systems and have particular overlapping conditions of bruxism, severe headaches, and restless leg syndrome accompanied by periodic limb movement during sleep.
Dysfunctional sleep can be caused by some type of airway obstruction causing sleep apnea where the person stops breathing several times a night; it can be due to abnormal cycles of sleep, where certain cycles are not present or brain activity, measured by brain waves, is abnormal. These abnormalities have an effect on maintaining sleep or sleep quality. Insomnia, which is not being able to get to sleep, is also considered dysfunctional. Many of us seldom, if ever, enter deep stages of sleep.
In sleep apnea or other obstructions to air flow, a person is deprived of oxygen needed for cellular metabolism and energy resulting in many of the symptoms listed in the introduction, and it can cause problems with the cardiovascular system. Obstructive sleep can also create disrupted sleep cycles and in a recent review, it was found that as many as one third of patients diagnosed with ME/CFS actually had primary sleep problem and not ME/CFS at all. For certain other patients, dysfunctional sleep is comorbid to FM and ME/CFS.
Symptoms of bruxism, teeth grinding, are unusual wear and tear on your teeth, continued breakdown of dental restorations, teeth breaking, and tooth sensitivity. Though the exact cause is unknown, it could be mediated in the central nervous system creating an unconscious response to pain or stress. While it is usually your dentist who notices the wear pattern on your teeth, it can also be identified in sleep studies. Teeth grinding can also increase the incidence of myofascial trigger points, TMJ, and migraine. You can read more on this connection here.
Restless leg syndrome (RLS) is often misused interchangeably with periodic limb movement (PLM). Periodic limb movement is repeated movement of legs, and sometimes arms, during sleep. While RLS and PLM often occur together, they are not the same. Restless leg occurs during wakefulness and PLM occurs during sleep.
In a small study done at Johns Hopkins University, Richard Allen, PhD, using an MRI, found glutamate, a chemical messenger in the central nervous system associated with arousal, to be abnormally high in patients with RLS and the quantity was associated with sleep quality. Maybe not so coincidentally, glutamate levels were also found to be elevated in the muscle of FM patients.
In summary, could disrupted sleep patterns, obstructive sleep function, bruxism, and periodic limb movement be major contributing factors to our sleep quality? The answer is yes. And should all fibromyalgia and chronic fatigue syndrome (ME/CFS) patients have their sleep evaluated with a sleep study, not only considering sleep wave progression and presence of obstructive sleep function, but also a specific assessment for bruxism and PLM?
Sleep deprivation can impede healing, foster agitation, and when severe, cause psychosis. This might explain why so many of us have difficulty fighting off viruses and recovering from injury, which is normally repaired during sleep. The prevalence of bruxism, RLS and PLM in fibromyalgia is significant and can be factors in sleep quality which is a primary symptom of fibromyalgia. I felt it so important that I wrote a couple of letters and advocated with one of the authors of the diagnostic criteria for an automatic referral for a sleep study.
In light of the significance of sleep in both FM and ME/CFS, I feel it important to discuss your symptoms with your doctor. They may or may not know the many factors associated, but most important is to get a sleep study. You could have a treatable condition that might improve your symptoms overall.
Allen RP, Barker PB, Horská A, Earley CJ. Thalamic glutamate/glutamine in restless legs syndrome: increased and related to disturbed sleep. Neurology. 2013 May 28;80(22):2028-34. doi: 10.1212/WNL.0b013e318294b3f6. Epub 2013 Apr 26.