Fibromyalgia is a chronic, nonarticular pain syndrome defined by widespread musculoskeletal pain and generalized tender points with other symptoms such as sleep disturbance, fatigue, headache, morning stiffness, paresthesia, and anxiety. Prevalence is 3.4% in women and 0.5% in men, with increasing prevalence to age 80 years and women being affected 10 times more frequently than men and familial clustering suggesting a genetic etiology.

This is a review of clinical features, management strategies, comorbidities, and differential diagnoses associated with fibromyalgia.

Diagnosis

Criteria for diagnosis of fibromyalgia are those issued by the American College of Rheumatology (ACR) in 1990. These include widespread pain with a minimum duration of 3 months and the presence of 11 or more tender points at 18 specific anatomic sites.

Diagnosis of fibromyalgia mainly depends on history and physical examination; ACR criteria used are widespread pain above and below the waist including the axial skeleton and presence of 11 tender points among 18 specified points. At presentation, patients may complain of pain at multiple sites, fatigue, poor sleep, and low back pain.
Comorbid conditions of fibromyalgia include anxiety and depression, headache and migraine, sleep disruption, irritable bladder, premenstrual syndrome, restless leg syndrome, temperomandibular joint pain, noncardiac chest pain, Raynaud's phenomenon, and sicca syndrome. Management strategies include pharmacotherapy, cognitive behavior therapy, education, and some types of complementary medicine.

Differential Diagnosis

Diagnosis is not by exclusion but by using ACR 1990 criteria; it mainly depends on history and physical examination.
ACR criteria include 2 components: widespread pain above and below the waist including the axial skeleton and presence of 11 tender points among 18 specified points.
Complaints at presentation include pain at multiple sites, fatigue, poor sleep, and low back pain that may radiate to buttocks and legs.
Cognitive impairment such as memory problems, headaches, dizziness, anxiety, and depression may occur.
The Fibromyalgia Impact Questionnaire is a self-administered instrument that is useful in assessing functional abilities in daily life and outcomes of treatment.
Systematic palpation at the 18 sites using a force of 8.8 lb (blanching of the examining thumbnail) is part of the physical examination for diagnosis.
Laboratory testing plays a limited role in diagnosis, and baseline tests used include complete blood count, thyroid-stimulating hormone testing, and comprehensive metabolic panel.
Triggers for symptoms include emotional stress, illness, surgery, and trauma.
Patients with higher count of tender points have been shown to have a higher incidence of childhood adverse experiences such as loss of a parent or abuse.
Comorbid conditions associated with fibromyalgia include alpha-delta sleep anomaly, altered sleep pattern with increase in stage 1 sleep, reduction in delta sleep, and sleep disruption, which also occurs with depression.
Anxiety and depression are the most common comorbidities.
Prevalence of migraines is higher than in the general population, headaches are a common complaint, and patients may also have irritable bowel syndrome and abdominal pain.
Other comorbid conditions include irritable bladder, premenstrual syndrome, restless leg syndrome, temperomandibular joint pain, noncardiac chest pain, Raynaud's phenomenon, and sicca syndrome.
The differential diagnoses for fibromyalgia include myofascial pain syndrome, chronic fatigue syndrome, hypothyroidism, metabolic and inflammatory myopathies (especially in patients taking statins), and polymyalgia rheumatica.

Conditions that should be considered in the differential diagnosis of fibromyalgia include myofascial pain syndrome, chronic fatigue syndrome, and hypothyroidism. Furthermore, these conditions may also be present in patients with fibromyalgia, which renders the diagnosis more difficult.

In recent years, recognition, understanding, and diagnosis of fibromyalgia have improved. Despite the absence of well-established treatment recommendations, a multidimensional approach can be effective.

Treatment

Management of fibromyalgia requires a multidimensional approach including patient education, cognitive behavioral therapy, exercise, and other treatment, according to a review published in the July 15 issue of American Family Physician.

Specific treatment recommendations are as follows:

Suggested treatment modalities include patient education, cognitive behavior therapy, exercise, physical therapy, and pharmacotherapy (level of recommendation, A, based on 5 randomized controlled trials).


Antidepressant medications may alleviate pain and improve sleep quality and global well-being in patients with fibromyalgia (level of recommendation, B, based on few randomized controlled trials).


Cyclobenzaprine, 10 to 30 mg at bedtime, may decrease pain and improve sleep quality in patients with fibromyalgia (level of recommendation, A, based on systematic review of randomized controlled trials).


Aerobic exercise training may ameliorate fibromyalgia symptoms (level of recommendation, A, based on systematic review of randomized controlled trials).
Fibromyalgia treatments for which there is strong evidence of effectiveness include amitriptyline, 25 to 50 mg at bedtime; cyclobenzaprine, 10 to 30 mg at bedtime; cardiovascular aerobic conditioning exercise; cognitive behavioral therapy; multidisciplinary therapy as discussed earlier; and patient education, which may take place in a group format using lectures, written materials, and demonstrations.

Fibromyalgia treatments for which there is moderate evidence of effectiveness include the dual-reuptake inhibitors duloxetine, venlafaxine, and fluoxetine, at doses of 20 to 80 mg at bedtime, either alone or in combination with a tricyclic antidepressant. Other pharmacotherapies backed by moderate evidence of effectiveness include pregabalin and tramadol, 200 to 300 mg daily, either alone or in combination with acetaminophen.

Nonpharmacologic therapies with moderate evidence of effectiveness in fibromyalgia are acupuncture, balneotherapy, biofeedback, hypnotherapy, and strength training.

Evidence to support the use of chiropractic therapy, electrotherapy, manual and massage therapy, or ultrasonography in patients with fibromyalgia is weak. Evidence to justify the use of corticosteroids, melatonin, nonsteroidal anti-inflammatory drugs, opioids, thyroid hormone, flexibility exercises, and injections of tender or trigger points is altogether lacking.

The effectiveness of acupuncture and biofeedback has been supported by some studies. Serum levels of substance P and serotonin were significantly elevated after acupuncture treatment, suggesting possible mechanisms in pain relief. Although their effectiveness has not been proven by controlled trials, other treatment modalities employed include chiropractic therapy, yoga, tai chi, massage therapy, magnetic therapy, and tender-point injections.

Guidelines from the American Pain Society assist in the definition and management of fibromyalgia. The 1990 ACR diagnostic criteria are also clinically useful, with the caveat that fibromyalgia can be diagnosed even if the ACR's tender point criteria are not met, provided the history is highly suggestive.

Now that there is an evidence- and consensus-based practical approach to the diagnosis and management of fibromyalgia, a higher quality of care can be provided to patients with this syndrome. Screening for disorders that may initiate or exacerbate symptoms of fibromyalgia is critical. If comorbid disorders are not identified early and treated appropriately, therapies that target fibromyalgia only as a primary disorder may be ineffective.

The editorial also highlights the controversy regarding the usefulness of opioids in fibromyalgia management, as well as the paucity of evidence supporting their use and the potential for opioid-induced hyperalgesia.

As with any chronic pain syndrome, patients should be carefully selected for opioid therapy, and a plan should be in place for appropriate follow-up and monitoring for pain reduction, outcome improvement, side effects, and misuse. Physician awareness of effective nonpharmacologic and pharmacologic therapies can minimize ineffective prescribing and patient frustration associated with failure of therapy. As growing evidence from well-designed studies becomes available, physicians can confidently employ a practical and evidence-based approach to this once ill-defined syndrome.

Pharmacologic treatment remains the mainstay of therapy.
Tricyclic antidepressants such as amitriptyline, 25 to 50 mg at bedtime, can provide analgesia and treat mood disorders.
Fluoxetine at 80 mg daily is of limited efficacy, and fluoxetine is more effective in combination with amitriptyline.
Tramadol may be used for analgesic effect for moderate to severe pain and needs to be titrated to avoid nausea and dizziness.
Cyclobenzaprine, 10 to 30 mg at bedtime, can improve sleep and reduce pain.
Pregabalin, a second generation anticonvulsant, has been shown to be effective at 450 mg daily for pain, fatigue, and improving sleep.
Other strategies of benefit include patient education, cognitive behavior therapy, and some forms of complementary and alternative medicine such as acupuncture and biofeedback.
Pearls for Practice