Fibromyalgia is a disorder characterized by musculoskeletal pain all over the body. Widespread pain is often accompanied with fatigue, sleep disturbance, memory-related problems, and emotional distress.
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Fibromyalgia is a chronic nervous system disorder, which is not associated with autoimmune or inflammation-related conditions. Although the condition does not cause any direct damage to tissues of the body, it may cause weakening of the muscles, leading to secondary problems.
Fibromyalgia most frequently occurs among middle-aged adults; however, the condition can also be seen among teenagers and elderly people.
People with rheumatic diseases, such as osteoarthritis, lupus, rheumatoid arthritis, or ankylosing spondylitis, are more likely to be diagnosed with fibromyalgia.
Patients with fibromyalgia have tender points on the body, particularly in neck, shoulders, back, hips, arms, and legs. People feel pain when pressure is applied to these points.
Back in the 1800s, physicians used to describe muscle pain-related conditions as rheumatism or muscular rheumatism. Later in 1904, the term fibrositis was first introduced by Sir William Gowers who described the condition as inflammation of the fiber.
The foundation of modern fibromyalgia was established in 1972 by Smythe who provided a thorough description on widespread pain and tender points. In 1975, the first sleep electroencephalogram study was carried out. With the evidence showing no connection with inflammation, the term fibrositis was replaced by fibromyalgia in 1976. The validation of known symptoms and tender points was first made in 1981 by a controlled clinical study, which also proposed the first data-based criteria of fibromyalgia. The connection between fibromyalgia and other similar conditions was proposed in 1984.
In 1987, fibromyalgia was first recognized by the American Medical Association as a defined disease entity, and the Journal of the American Medical Association (JAMA) published an article by Goldenberg describing the clinical manifestations, laboratory findings, and treatment outcomes of fibromyalgia patients. Finally in 1990, the first American College of Rheumatology criteria were published.
Fibromyalgia is a frequently occurring pain-related condition, affecting about 3 – 6% of people worldwide.
According to the National Fibromyalgia Association, about 10 million people are affected by this disorder In the United States. Based on the National Health Service data, about 2 – 4.5% of people in the United Kingdom have fibromyalgia.
Women are more like to develop fibromyalgia than men; about 75 – 90% of fibromyalgia patients are women. In general, the diagnosis is made between ages 20 – 50 years; however, the incidence increases with age.
Fibromyalgia is often accompanied by several co-morbid psychiatric conditions, such as depression, anxiety, personality disorder, obsessive-compulsive disorder, and post-traumatic stress disorder.
Because there are no specific diagnostic methods (physical examination or laboratory tests) for the condition except for the presence of pain at characteristic tender points, fibromyalgia patients consider the illness as a stigmatized and imperceptible disorder. In many cases, patients have negative perception about self-image and body-image; suffer from low self-esteem and negative self-efficacy; as well as develop suicidal tendency.
Taken together, these entire incidences give rise to the controversy that fibromyalgia may be a psychological condition and not a physical disease.
According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), a question has been put forward recently that whether fibromyalgia can be categorized as a somatic symptom disorder and therefore as a mental disorder.
Somatic symptom disorder is characterized by a person’s extreme focus on physical symptoms, such as pain and fatigue, which significantly increases his/her emotional distress.
Although widely regarded as a mental disorder, there are many factors suggesting that fibromyalgia is a physical disorder.
The most important evidence is that there are well-defined criteria of the American College of Rheumatology for diagnosing fibromyalgia. Based on these criteria, physicians are able to diagnose and differentiate fibromyalgia from other rheumatic diseases with 85% efficacy.
In addition, experimental evidence on the involvement of peripheral and central nervous systems as well as hypothalamic-pituitary-adrenal axis further suggests that altered stress regulation as well as neuro-hormonal changes may be responsible for the widespread pain and emotional distress associated with fibromyalgia.
Although exact etiology is unknown, scientific studies claim that a crosstalk between physical, neurological, and psychological factors plays the primary role in developing fibromyalgia.
It is believed that repeated stimulation of nerves in the brain alters the level of certain neurotransmitters that are responsible for pain-related signaling. Moreover, pain receptors in the brain develop a kind of pain memory, which makes them extra sensitive and overreactive to pain signals.
The levels of two principle neurotransmitters namely serotonin and norepinephrine are found to be reduced in the cerebrospinal fluid of fibromyalgia patients.
Many studies indicate that reduced levels of these neurotransmitters are responsible for reduced ‘conditioned pain modulation’ (a psychophysical process of measuring endogenous pain inhibitory pathway) in fibromyalgia patients.
In fibromyalgia, the brain perceives and analyzes pain and other sensory signals differentially (pain amplification), which makes a person more susceptible to pressure, temperature, bright light, and noise. However, the pain associated with fibromyalgia is different from that experienced in other diseases, such as arthritis. This is because no physical damage or injury to any body part is involved in fibromyalgia. Since there is no particular damage to be healed, the pain can be widespread and chronic.
There are certain predisposing factors for fibromyalgia. These include stressful or traumatic conditions (car accident), repetitive joint or muscle injuries, certain diseases (rheumatoid arthritis and other autoimmune diseases), viral infections, obesity, and psychological distress (childhood abuse, exposure to catastrophic events, low job satisfaction, etc.).
Fibromyalgia often runs in families, indicating that certain genetic factors may be responsible for the disease development. The first-degree relatives (siblings or children) of fibromyalgia patients are 8 times more susceptible to get the disorder. However, little is known about the responsible genes. It is believed that several genes may together play a role in disease development.
Certain candidate genes that are suspected to play roles in disease pathogenesis include hydroxytryptamine receptor 2A, serotonin transporter, Catechol-O-methyl transferase, D4 dopamine receptor, adrenergic receptor, etc.
The signs and symptoms of fibromyalgia vary from person to person. The intensity of symptoms also fluctuates over time.
The most common symptoms of fibromyalgia are widespread pain and stiffness, extreme tiredness, and sleep disturbance. People often describe the pain as a persistent dull ache lasting for at least 3 months.
Because of such constant pain, sleep is greatly disturbed; in some cases, people develop certain sleep disorders, such as restless legs syndrome and sleep apnea.
All these disturbances are mainly responsible for extreme tiredness, which subsequently causes lack of concentration/attention, memory problems, and difficulty thinking. This is commonly called as ‘fibro fog’ or ‘brain fog’. In many cases, people with fibromyalgia suffer from psychiatric problems including depression and anxiety.
Fibromyalgia often comes with different comorbidities, such as headache, migraine, irritable bowel syndrome, painful bladder syndrome, and temporomandibular joint syndrome. Women with fibromyalgia often feel extreme pain during menstruation.
Because of the long-lasting pain, people sometimes suffer from muscular twitch or cramp and tingling or numbness in the hands and feet. Some digestive problems, such as abdominal pain, bloating, and constipation, are also commonly seen in fibromyalgia patients.
Because of its close association with irritable bowel syndrome and reduced salivary secretion, fibromyalgia patients sometimes suffer from dry mouth syndrome. This is commonly associated with dry eye syndrome in patients with fibromyalgia. Patients who develop psychiatric problems are particularly at higher risk of developing dry eye syndrome.
Diagnosis of fibromyalgia is often very difficult because of the symptom similarity with other diseases including hypothyroidism, chronic fatigue syndrome, and rheumatoid arthritis. Initially, doctors ask patients to describe their pain; this helps distinguish the nature of pain from other related disorders.
Fibromyalgia pain can be of different types:
- Hyperalgesia – is a type of pain amplification where pain felt is much larger than the stimulus applied.
- Paresthesia – occurs due to auto-stimulation of nerves, in which patients feel tingling, burning, itching or numbing sensation over the area.
- Allodynia – feeling of intense pain even due to a mild touch or pressure from clothing or gentle massage. The pain may also arise from mild heat or cold exposure.
Until recently, the diagnosis of fibromyalgia was mainly made using the tender point test. In this test, doctors check if a suspected person feels pain when specific tender points on the body are pressed firmly. However, according to the 2010 guidelines of the American College of Rheumatology, tender point test is no longer required to diagnose fibromyalgia.
Criteria required for diagnosis are as follows:
- A person having pain and related symptoms over the past week, based on the total number of painful areas out of 19 parts of the body, as well as the intensity of symptoms (fatigue, waking unrefreshed, and cognitive problems)
- A person having widespread pain and symptoms for at least 3 months at a similar level
- No underlying disorder is present that can be responsible for the pain and symptoms
To date, no blood test or imaging test is available to diagnose fibromyalgia. However, doctors sometimes recommend blood tests to rule out the possibility of other pain-causing disorders. These tests include total blood count, erythrocyte sedimentation rate, cyclic citrullinated peptide test, rheumatoid factor, and thyroid function test.
Chronic pain and fatigue associated with fibromyalgia greatly interfere with patient’s day-to-day activity and social behavior, leading to reduced quality of life. Since the condition is often misunderstood clinically, patients may feel frustrated and depressed. Having fibromyalgia also increases the rate of hospitalization by two times.
Certain measures that are effective in managing the symptoms include:
- Exercise regularly
- Practice relaxation techniques, such as yoga, meditation
- Try to reduce stress and get enough sleep
- Eat healthy and avoid smoking, drinking alcohol
Alternative therapies, such as acupuncture or massage therapy, may also be helpful in reducing pain and stress levels.