Neurologic signs common with fibromyalgia

By Michelle Rizzo

NEW YORK (Reuters Health) - Fibromyalgia isn't all in your head, new research suggests.

In a study, researchers found that people with fibromyalgia were more likely than those without the chronic pain condition to have poor balance, tingling and weakness in the arms and legs, and other "neurologic" signs and symptoms.

Fibromyalgia, a debilitating pain syndrome that affects 2 to 4 percent of the population, is characterized by chronic pain, fatigue and difficulty sleeping. It's a somewhat mysterious condition with no clear-cut cause. Many people with fibromyalgia have faced the question of whether the condition is real.

The new findings, reported in the latest issue of Arthritis and Rheumatism, support a growing body of literature suggesting that the condition is real and also support the possibility that a "neuroanatomical" cause may underlie fibromyalgia.

Dr. Nathaniel F. Watson, of the University of Washington Medicine Sleep Institute at Harborview, Seattle, and colleagues studied 166 people with fibromyalgia and 66 pain-free controls.

All of them were examined by a neurologist who was unaware of their disease status. All study participants also completed a standard questionnaire on neurologic symptoms.

In 27 of 29 neurological categories tested, significantly more neurologic symptoms were seen in the fibromyalgia group than in the control group, Watson and colleagues found.

The greatest differences were found for light sensitivity, or "photophobia," seen in 70 percent of fibromyalgia patients but in only 6 percent of pain-free controls; poor balance, which plagued 63 percent of fibromyalgia patients but only 4 percent of controls; and weakness and tingling in the arms or legs, seen in more than half of fibromyalgia patients but in only around 4 percent of controls.

In addition, those with fibromyalgia had greater dysfunction than controls in certain nerves in the brain. They also had more "sensory" problems, motor abnormalities and gait problems.

Within the fibromyalgia group, there were significant correlations between several neurologic signs and symptoms. For example, numbness in any part of the body or tingling in the arms or legs correlated with neurologic test findings. Poor balance, poor coordination and weakness in the arms or legs also correlated with objective findings on neurologic tests.

These observations, Watson told Reuters Health, underscore the need for "careful neurological examinations in all fibromyalgia patients, particularly those with neurological complaints."

Watson cautioned that this study does not confirm a neuroanatomical basis for fibromyalgia and that much more work is necessary before this can be known with certainty.

SOURCE: Arthritis and Rheumatism, September 2009.