Expert Guest Dr. Sherif Nasef
Fibromyalgia is a common chronic widespread pain condition. Patients often describe their pain as aching, exhausting, nagging or hurting. Most patients suffer from sleep disturbance, fatigue, cognitive difficulties (fibrofog) and morning stiffness. Multiple comorbidities have been reported with fibromyalgia including tension/migraine headaches, irritable bowel syndrome, temporomandibular disorder, interstitial cystitis, chronic pelvic pain and depression. Fibromyalgia affects 2-4 % of the US population, however, only half of those are diagnosed. It is about seven times more common in women and the typical age of onset is between 20 and 55 years. Fibromyalgia appears to be caused, at least partially, by genetic factors, as several genetic mutations were able to be associated with fibromyalgia. First degree relatives of fibromyalgia patients were more than eight times more likely to develop fibromyalgia than non relatives. Environmental factors have also been seen to play a role in fibromyalgia development. Fibromyalgia patients tend to report more stressful negative lifetime events than healthy controls and, in recent months, fibromyalgia has had a significant impact on the health care system. In one study, the annual health care costs for fibromyalgia patients were three times higher than patients with other diseases.
Although the underlying cause of fibromyalgia has not been established, recent data suggests that alteration of pain processing by the central nervous system may contribute to the chronic wide spread pain. Fibromyalgia is the prototype of a unique type of pain referred to as central sensitization syndrome.
According to the American College of Rheumatology, fibromyalgia can be diagnosed when a patient with at least three months of widespread pain shows 11 or more of the classic 18 “tender points” during a physical exam. Because many fibromyalgia patients have fewer than eleven tender points, a new validated questionnaire has been developed to replace these criteria.
Although there is no commercially available lab tests or imaging studies to confirm the diagnosis of fibromyalgia, several research methods have been used successfully. In research studies, the concentration of chemicals substance P and glutamate were higher in the fluid that surrounds the brain in fibromyalgia patients than in controls. A much less invasive way to test this theory is a special type of MRI called functional MRI, which showed wider areas of the brain activated by non painful stimuli in fibromyalgia patients compared to controls.
Treatment of fibromyalgia includes non pharmacologic therapies as well as medications. Moderately intense aerobic exercise has shown to improve pain but gradual exercise progression is advised to avoid exacerbation of symptoms. Intensive patient education also improves pain, sleep, fatigue, and quality of life. There has been some evidence of improvement in pain, fatigue, mood, and physical function with cognitive behavioral therapy. Other modalities include acupuncture, biofeedback, water therapy, and strength training.
The earliest clinical trial for medications to treat fibromyalgia in 1986 looked into amitriptyline (Elavil), which is a widely used tricyclic antidepressant. Amitriptyline was the recommended first line treatment at that time. The results of multiple trials on that medication and similar medications were mixed in terms of achieving significant improvement of fibromyalgia symptoms. Trials on opioid analgesics – including IV Morphine – failed to show significant improvement with the exception of Tramadol (Ultram), which is an opioid medication that increases serotonin and norepinephrine levels in the brain. Tramadol has been used for the treatment of fibromyalgia when there was no FDA approved medications for it. The anticonvulsant gabapentin (Neurontin) was effective in reducing fibromyalgia pain in a small study. Pregablin (Lyrica) is another anti-convulsant that emerged as the first FDA approved medication for fibromyalgia after it showed statistically significant improvement in pain when used by itself for fibromyalgia in a placebo controlled trial. Dizziness and somnolence happened in 38% and 20% of the study patients taking the medication respectively. Duloxetine (Cymbalta) was FDA approved for fibromyalgia several years later to provide another option through a different mechanism of action. Being an anti-depressant, it addressed a common problem seen in fibromylagia patients. Nausea was reported in 29% of the patients taking that medication in the clinical trials. Milnacipran (Savella) which belongs to the same category of medications as Duloxetine was the last FDA approved medication for fibromyalgia after showing significant improvement in a 3-measure composite response in a 3 month trial. In addition to nausea, new onset hypertension was another common adverse event. Monitoring of blood pressure is recommended while taking this medication.
Even though only three medications are FDA approved for fibromyalgia at this time, we are much more advanced in our understanding and treatment of the disease than we were ten years ago. New medications are constantly being tested as treatments for fibromyalgia. Patients and physicians continue to be hopeful that the future might bring a cure for such a disabling and widespread disease.
