Fibromyalgia - Causes

Causes

Fibromyalgia is grouped into two categories:

• Primary (idiopathic) fibromyalgia -- the causes are not known.
• Secondary fibromyalgia -- the causes can be identified.

Primary fibromyalgia is the most common type. Many experts believe that fibromyalgia is not a disease but rather a chronic pain condition brought on by several abnormal body responses to stress. Physical injuries, emotional trauma, or viral infections such as Epstein-Barr may be triggers of the disorder, but none have proven to be a cause of primary fibromyalgia.

Research published in the December 2006 issue of Current Pain and Headache Reports found that the areas in the brain that are responsible for the sensation of pain are different in fibromyalgia patients from the same areas in healthy people.

Chronic Sleep Disturbance

Sleep disturbances are common in fibromyalgia. Both adult and young patients with fibromyalgia have a higher than average rate of a sleep disorder called periodic limb movement disorder (PLMD). PLMD used to be called nocturnal myoclonus. Patients with PLMD involuntarily contract their leg muscles every 20 - 40 seconds during sleep. This may occasionally wake up the patient.

Some experts believe that fibromyalgia does not lead to poor sleeping patterns, but that sleep disturbances come first. Researchers continue to investigate the link between fibromyalgia and sleep.

• In one study, healthy volunteers reported fibromyalgia-like pain after they had been subjected to disrupted deep sleep. Disturbed sleep appears to trigger factors in the immune system that cause inflammation, pain, fatigue, and lower tolerance to pain. A 2004 study found that patients with fibromyalgia have increased rates of cyclic alternating sleep pattern (CAP). Increased CAP produced serious sleep problems, which were strongly linked to symptom severity. Previous studies have also suggested that CAP may be related to PLMD.
• A 2004 report found that sleep disorders that cause breathing problems are common in women with fibromyalgia.
• Other biological measures of troubled sleep, however, such as levels of the hormone melatonin, which helps to regulate circadian rhythms and the sleep-wake cycle, appear to be normal in most fibromyalgia sufferers.