What is Fibromyalgia?
Fibromyalgia is characterised by chronic widespread pain and allodynia (a heightened and painful response to pressure).
Other symptoms include debilitating fatigue, sleep disturbance, and joint stiffness.
Some people also report difficulty with swallowing, bowel and bladder abnormalities, numbness and tingling, and cognitive dysfunction.
Fibromyalgia is frequently associated with psychiatric conditions such as depression and anxiety and stress-related disorders such as post traumatic stress disorder. Not all people with fibromyalgia experience all associated symptoms.
Its exact cause is unknown but is believed to involve psychological, genetic, neurobiological and environmental factors.
There is evidence that environmental factors and certain genes increase the risk of developing fibromyalgia – these same genes are also associated with other functional somatic syndromes and major depressive disorder.
The central symptom of fibromyalgia, namely widespread pain, appears to result from neuro-chemical imbalances including activation of inflammatory pathways in the brain which results in abnormalities in pain processing.
The brains of fibromyalgia patients show functional and structural differences from those of healthy individuals, but it is unclear whether the brain anomalies cause fibromyalgia symptoms or are the product of an unknown underlying common cause.
Fibromyalgia, a central nervous system disorder, is described as a "central sensitization syndrome" caused by neurobiological abnormalities which act to produce physiological pain and cognitive impairments as well as neuro-psychological symptomatology.
Fibromyalgia is classed as a disorder of pain processing due to abnormalities in how pain signals are processed in the central nervous system.
Differences in psychological and autonomic nervous system profiles among affected individuals may indicate the existence of fibromyalgia subtypes. A review divides individuals with fibromyalgia into four groups as well as "mixed types":
1. Extreme sensitivity to pain but no associated psychiatric conditions (may respond to medications)
2. Fibromyalgia and comorbid, pain-related depression (may respond to antidepressants)
3. Depression with concomitant fibromyalgia syndrome (may respond to antidepressants)
4. Fibromyalgia due to somatization (may respond to psychotherapy)
The defining symptoms of fibromyalgia are chronic widespread pain, fatigue, sleep disturbance, and heightened pain in response to tactile pressure (allodynia).
Other symptoms may include tingling of the skin (paresthesias), prolonged muscle spasms, weakness in the limbs, nerve pain, muscle twitching, palpitations, and functional bowel disturbances.
Many patients experience cognitive dysfunction (known as "fibrofog"), which may be characterized by impaired concentration, problems with short and long-term memory, short-term memory consolidation, impaired speed of performance, inability to multi-task, cognitive overload, and diminished attention span.
Fibromyalgia is often associated with anxiety and depressive symptoms.
Although fibromyalgia is classified based on the presence of chronic widespread pain, pain may also be localized in areas such as the shoulders, neck, low back, hips, or other areas.
The cause of fibromyalgia is unknown. However, several hypotheses have been developed including "central sensitization".
This theory proposes that fibromyalgia patients have a lower threshold for pain because of increased reactivity of pain-sensitive nerve cells in the spinal cord or brain.