What Causes Fibromyalgia?

No one knows for sure what causes fibromyalgia. Researchers suspect that many different factors, alone or in combination, may contribute to the development of fibromyalgia. For example, factors such as an infectious illness, physical trauma, emotional trauma or hormonal changes may trigger the development of generalized pain, fatigue and sleep disturbances that characterize the condition.

Studies have suggested that people with fibromyalgia have abnormal levels of several different chemicals in their blood or cerebrospinal fluid that help transmit and amplify pain signals to and from the brain. There also is evidence that the central nervous system’s ability to inhibit pain is impaired in these people. In addition to patient reports, brain-imaging studies have confirmed that when fibromyalgia patients are given a small amount of pressure or heat, they experience much higher amounts of pain, as if the “volume control” is set too high on pain processing. Whether these abnormalities are a cause or a result of fibromyalgia is unknown.

Who Gets Fibromyalgia?

Fibromyalgia affects more than 3.7 million Americans, the majority of whom are women between the ages of 40 and 75, but it also affects men, young women and children as well. People with other rheumatic diseases, such as rheumatoid arthritis or lupus, are at greater risk for fibromyalgia. For example, about 20 to 30 percent of people with rheumatoid arthritis also develop fibromyalgia, although no one knows why.

Fibromyalgia sometimes occurs in more than one member of the same family, but doctors have not verified a hereditary link or common genetic type. Several studies have, however, found a possible link between genetic markers called human leukocyte antigens, or HLAs, and fibromyalgia. This suggests that a gene that predisposes a person to develop fibromyalgia may exist.

Difficult to Diagnose

Unlike diabetes, which can be diagnosed with a simple blood test, fibromyalgia does not show up on lab tests. Unlike rheumatoid arthritis, which can cause joints to become swollen and deformed, fibromyalgia’s effects on the body are invisible. Most people with fibromyalgia don’t look sick. In most cases, the only clue there’s a problem is the person’s complaints of hurting all over or constantly feeling tired. Thus, many people – doctors included – have incorrectly assumed the condition is all in the patient's head.

Increasingly, however, that attitude is changing. The more researchers learn about this condition, the more doctors are taking it seriously.