Sleep Disorders and Fibromyalgia
Sleep disorders and Fibromyalgia go hand in hand – it is a defining symptom. The 1990 study that established the diagnostic criteria for Fibromyalgia found that up to 85% of patients reported fatigue and sleep disturbances (including insomnia and non-restorative sleep). More recent studies have reported sleep disturbances in as many as 90% of the patients studied. Furthermore, revised diagnostic criteria for Fibromyalgia, published in 2010 by the American College of Rheumatology, now incorporate not only widespread pain and tenderness, but also recognize other common symptoms as part of a comprehensive diagnosis, including fatigue/tiredness and insomnia (Roizenblatt et al., 2011).
Common Sleep Problems Among Fibromyalgia Sufferers
Fibromyalgia sufferers can experience a number of different sleep-related problems, many of which they may collectively refer to as insomnia (Spaeth et al., 2011). Insomnia typically refers to difficulty initiating or maintaining sleep, or non-restorative sleep, for at least a month in duration, with resulting distress or impairment in social, occupational, and other important areas of functioning (Spaeth et al., 2011). Non-restorative sleep includes sleep that is light or of poor quality. Fibromyalgia patients may also report excessive daytime sleepiness and fatigue. A number of specific sleep disturbances have been documented in Fibromyalgia sufferers, including alpha anomalies, sleep apnea, restless leg syndrome, periodic limb movement disorder, and bruxism.
Alpha EEG anomalies are sudden bursts of brain activity – indicated as alpha waves on an EEG monitor – that occur during times when the brain should be in a deep sleep phase. These bursts of intense brain activity mimic being awake and therefore prevent sufferers from getting deep, restful sleep. This leads to intense feelings of fatigue and tiredness the following day. Sleep apnea affects approximately 80% of patients with Fibromyalgia and is a dangerous condition in which an individual periodically stops breathing while asleep. The pauses in breathing can last in duration from a few seconds to several minutes, and can occur anywhere from five to 30 times per hour. In addition to the pauses in breathing, sleep apnea disrupts sleep and causes sufferers to shift from deep sleep into lighter sleep phases when breathing pauses. This all culminates in poor sleep quality that leads to a feeling of fatigue and tiredness the following day.
Restless leg syndrome (RLS) is a condition in which an individual feels the overwhelming urge to move the legs in order to stop unpleasant sensations. These symptoms usually occur at night while the individual is lying down and trying to sleep and may persist for as long as an hour or more. They are only relieved by walking or moving the legs, actions which result in a loss of sleep for the affected individual.
Periodic limb movement disorder (PLMD) is closely related to RLS and is characterized by repetitive limb movements that occur while an individual is in the lighter stages of sleep. The legs, ankles, and feet are most often involved and movements include things such as flexion of the big toe, ankle, knee, and hip. The movements occur at regular intervals, generally between five to 90 seconds apart. Individuals who suffer from PLMD report frequent nighttime awakenings, poor sleep quality, excessive daytime fatigue, and daytime sleepiness.
Finally, bruxism is a condition marked by the grinding, gnashing or clenching of one’s teeth. Individuals with bruxism unconsciously clench teeth together during the day or night. Nighttime bruxism is referred to as “sleep bruxism.” Bruxism may also be related to a disease that commonly affects Fibromyalgia suffers – temporomandibular joint disorder (TMJD). TMJD causes severe pain in the jaw joint, which may radiate into the face, neck, shoulders and back. As many as 70% of Fibromyalgia patients may have TMJD (Blasubramaniam et al., 2007).
Not only does the pain of Fibromyalgia make sleeping difficult, the constant sleep deprivation aggravates and worsens the pain associated with Fibromyalgia and leads to the development of other symptoms and conditions, such as fatigue, anxiety, depression, and difficulty concentrating (a symptom frequently referred to as “fibro fog”). Some research has shown a cyclical association between the severity of Fibromyalgia symptoms, sleep disturbances, and daytime pain. For example, daytime pain leads to poor sleep quality, which results in daytime fatigue the following day. That fatigue further worsens the pain, which further disrupts the next attempt to sleep, and so on (Edinger et al. 2005; Miro et al., 2011; Nicassio et al., 2002).
A 2011 study by Mrio et al. evaluated the reciprocal relationship between pain and sleep disturbances in 104 women with Fibromyalgia and 86 healthy control subjects. Each subject completed a series of questionnaires designed to assess pain severity, sleep quality, anxiety and depression, self-efficacy, and level of functioning. They also completed a one to 1.5 hour semi-structured interview that focused on their symptoms, life history, work, lifestyle, relationships, attitudes about Fibromyalgia, and psychological status. The researchers found that the Fibromyalgia group had worse overall sleep quality, including shorter sleep duration, more sleep disturbances, and increased use of sleep-inducing medications compared to the healthy control subjects. They also found that the Fibromyalgia group experienced higher levels of anxiety and depression. In addition, Miro et al. found that poor sleep quality was related to greater pain intensity, anxiety, and depression, as well as lower levels of self-efficacy and functioning, findings that illustrate the cyclical relationship between pain and sleep in Fibromyalgia patients. The authors also note that their findings suggest that sleep disturbances and decreased self-efficacy help mediate the relationship between pain and emotional problems, such as depression and anxiety, in Fibromyalgia patients (Miro et al., 2011).
A 2007 study by Theadom et al. evaluated 101 patients with Fibromyalgia to determine the relationship between sleep and coping on health-related quality of life. The researchers used a series of questionnaires to assess each patient’s sleep over the previous month, ability to cope problematically and emotionally, and health-related quality of life. The researchers found that 99% of the subjects experienced poor sleep, including shortened duration and feeling unrefreshed the following day. The authors also found that poor sleep quality was predictive of pain, fatigue, and decreased social functioning (Theadom et al., 2007).