What is Fibromyalgia and Who is Affected?

What is Fibromyalgia

Fibromyalgia, also known as Fibromyalgia Syndrome (FMS), is a debilitating, chronic disease characterized by body aches, fatigue, and pain in specific points in the body. Insomnia, lack of concentration and mood disturbances may also accompany these symptoms. In recent years more is being understood about the disease and its causes and diagnosis.

According to the medical dictionary: fibromyalgia is a neurosensory disorder characterized by widespread muscle pain, joint stiffness, and fatigue. The condition is chronic (ongoing), but pain comes and goes and moves about the body. The disorder is often misdiagnosed or unrecognized and is and often complicated by mood and anxiety disorders.

Fibromyalgia syndrome is also subject of keen psychiatric interest. Dr. Bradley* explained that fibromyalgia may be part of a group of affective spectrum disorders (ASD). The ASD hypothesis proposed by Hudson† and colleagues suggests that this group includes, but is not limited to, 10 psychiatric and 4 medical disorders that share 1 or more physiologic abnormalities important to their aetiology. These include inherited factors that may contribute to enhanced pain sensitivity, diminished pain inhibitory function, or mood disorders. Studies of patients, as well as their first-degree relatives, with fibromyalgia or rheumatoid arthritis have provided evidence to support the ASD hypothesis. For example, Arnold** and colleagues reported that the first-degree relatives of patients with fibromyalgia, compared with those of patients with rheumatoid arthritis, more frequently met diagnostic criteria for fibromyalgia or major depressive disorder (MDD) and exhibited a greater number of sensitive tender points (i.e., enhanced pain sensitivity). Hudson† and colleagues further examined data from this family study and found that fibromyalgia co-aggregated with 1 or more other forms of ASD whether mood disorders were included (p = .004) or not (p = .012). These findings suggest that, consistent with the ASD hypothesis, (1) heritable as well as environmental factors may contribute to family aggregation of pain sensitivity in fibromyalgia, (2) fibromyalgia co-aggregates with other affective spectrum disorders, and (3) these disorders may share heritable physiologic abnormalities.

Fibromyalgia 1990 – 2010

American College of Rheumatology had appointed a group medical doctors that formed Multicenter Criteria Committee who defined criteria for the classification of fibromyalgia in 1990. This has been presented in the bookmark  → diagnosis .

Fibromyalgia belongs to the group of illnesses defined as "soft tissue rheumatism" or "non joint rheumatism". The illness belongs to the most common peri-articular* chronic pain non-inflammatory disorder. The widespread pain is accompanied by hyperaesthesia in characteristic localization – so called tender points. Moreover, heavy, general, and chronic tiredness (chronic fatigue syndrome), sleep disturbances, and low mood or depression often occur. All these symptoms defined as the major criteria are accompanied by other various and more or less intense symptoms and disorders called as vegetative or functional.

It is estimated that, even in the US where fibromyalgia awareness is relatively high, it takes approximately five years from first symptoms to the final diagnosis. Patient sees at least 15 doctors of various specialities in that time. The variety and number of symptoms accompanying fibromyalgia is a real nightmare for patients and causes frequent and unproductive visits to different specialists and various examinations like blood tests as well as imaging scans (x-rays, NMR**, CT scans†, and USG scans‡.

Fibromyalgia after 2010

It is important to understand the impact of this illness on patient, her/his family, and community, when investigating fibromyalgia epidemiology. The modified new ACR diagnostic criteria of fibromyalgia in 2010 enables to perform broad epidemic research in different countries and continents without a necessity to examine tender points. This also would make possible to evaluate socio-demographic determinants of fibromyalgia and its coexistence with other disorders.

On the base of many (several dozen) epidemic survey performed according to fibromyalgia diagnostic criteria published by ACR in 1990 the average rate of fibromyalgia prevalence was 2.7 % of the total world population.

There are available three surveys applying the new (2010) diagnostic criteria of fibromyalgia, only (in the USA¹, Germany², Tailand³). It seems that the new criteria are more sensitive and less specific as compared to the old (1990) ACR diagnostic criteria. This may reflect on increased number of diagnosed fibromyalgia cases.

Primary Fibromyalgia

Primary fibromyalgia (FMS) also known as idiopathic fibromyalgia. In primary fibromyalgia, the causes are not known and primary fibromyalgia seems to be vaste majority of all fibromyalgia cases.

Juvenile primary fibromyalgia syndrome (JPFS) is a musculoskeletal pain syndrome characterized by multiple discrete tender points (TPs), fatigue, and sleep disturbance in the child and adolescent. JPFS can be chronic in nature and can necessitate a multidisciplinary approach to the ongoing treatment of the disorder. The pain experienced is modulated by factors such as activity, anxiety, stress, and weather changes.

The diagnosis is made on the basis of the presence or absence of specific criteria that have been found to be consistent with those who experience JPFS. The chronic nature of fibromyalgia in the pediatric population suggests consequences for psychosocial development and implies a more difficult transition from childhood to adulthood.

Secondary Fibromyalgia

Secondary fibromyalgia has similar symptoms as primary fibromyalgia. Possible causes of secondary fibromyalgia include:

• Physical injury. For example, secondary fibromyalgia sometimes develops in people who have had neck injuries.
• Ankylosing spondylitis. Ankylosing spondylitis is a form of chronic inflammation of the spine and the sacroiliac joints located in the low back where the sacrum meets the iliac bones.
• Surgery. Trauma, particularly in the upper spinal region, may trigger the development of fibromyalgia.
• Lyme disease.
• Hepatitis C.
• Endometriosis.

Fibromyalgia Prevalence

Fibromyalgia is one of the most common chronic pain conditions. The disorder affects an estimated 3 – 6% of the world population (7.6 billons in 2018). This gives from 228 million even up to 456 million all over the world. However, it varies from country o country. The diagnosis of fibromyalgia is difficult and there might a number of false positively or false negatively misdiagnosed people.

Fibromyalgia is most prevalent in women. Between 75 – 90 percent of the people who have FM are women. Fibromyalgia also occurs in men and children of all ethnic groups. The disorder is often seen in families, among siblings or mothers and their children. The diagnosis is usually made between the ages of 20 to 50 years, but the incidence rises with age so that by age 80, approximately 8% of adults meet the American College of Rheumatology classification of fibromyalgia.

Fibromyalgia percentage prevalence is presented is some contries, hereinafter:

Fibromyalgia Prevalence in Different Groups and Populations

Fibromyalgia may affect anybody regardless of age, gender, race, and territory. However, women are affected 5 – 10 times more often. Majority of patients is between 30 - 60 years, also in productive age.

The literature shows values of fibromyalgia prevalence in the general population between 0.2 and 6.6%, in women between 2.4 and 6.8%, in urban areas between 0.7 and 11.4%, in rural areas between 0.1 and 5.2%, and in special populations values between 0.6 and 15%. This literature review update shows a significant increase in fibromyalgia prevalence studies in the world. The new 2010 American College of Rheumatology criteria have not been widely used yet and the COPCORD (Community-oriented program for control of Rheumatic Diseases) methodology has increased the quality of studies on the prevalence of rheumatic diseases in General. (source: Pasqual Marques A, De Sousa A, et al. Prevalence of fibromyalgia: literature review update; Rev.Bras.Reumatol. 2017;57(4):356–363)

• In women age from 20 to 49 in Arendal, Norway a rate was 10.5 %
• In women in Trabzon, Turkey age from 20 to 64 years, a rate was 3.6 %.
• In school children age (9 – 15 years) in Mexico fibromyalgia rate was of 1.2 % of investigated children.
• In elderly subjects, 65 years or older, in São Paulo, Brazil, a rate of 5.5% was found.
• In hospitalized patients of a primary care unit of Seoul, South Korea the rate was 1.7%.
• Gallinaro et al. found a 10.4 % prevalence of FM in metalworkers without repetitive strain injuries, and 58.8 % in those with this condition*.
• Among textile workers in Denizli, Turkey, the rate was 7.3 % (9.0 % in females and 0.8 % in males)
• In hospital workers in Japan, the rate was 2.0 % in women and 0.5 % in men.
• In the Amish community of London, Ontario, Canada, the rate was 7.3 % (10.4 % in females and 3.7 % in males).
• In a low socioeconomic status population in Embu, São Paulo, Brazil, assisted by the public primary health care system, the rate was 4.4 %.
• In patients of 16 general practices of Marche, Italy, the rate 2.2 %.
• Patients of a health insurance company in Germany, the rate was 0.4 % of women and 0.05 % of men.
• According to the U.S. Centers for Disease Control and Prevention, the prevalence of FMS is 3.4% in women and 0.5% in men. [U.S. Centers for Disease Control and Prevention*]