This report was extracted from list@hdot.tv.

NEW YORK (Reuters) -- Fibromyalgia, a disease featuring fatigue and muscle pains, affects 1 in every 20 people. Researchers say they may have discovered the first physical clues to the origins of the disease.

"This finding should provide some relief to millions of people who have been told that their pain is all in their head," says Laurence Bradley, PhD, who led a University of Alabama study into the origins of the disease. There's never been real physical evidence of fibromyalgia from the usual tests -- up to now, blood samples and tissue biopsies from patients with the disease have shown no apparent abnormalities.

Because of this, some researchers have theorized that fibromyalgia is a psychological rather than a physical ailment. But using cerebrospinal fluid drawn from spinal taps performed on those with fibromyalgia, Bradley's team discovered higher levels of a brain chemical called Substance P.

Bradley says Substance P is a neurological chemical which "allows cells in the nervous system to communicate with one another about potentially harmful stimuli," and create the sensation of pain.

Substance P levels are doubled or tripled in fibromyalgics, says Bradley. This, in turn, could produce more episodes of pain transmission throughout the body, he explained.

Researchers also used high-tech brain imaging on fibromyalgia patients, and found lower blood flow to segments of the brain specifically concerned with pain transmission. "If these pain centres are not working efficiently, they might not be inhibiting pain transmission as well as they should," said Bradley. In other words, in healthy individuals, these 'pain centres' keep the gates closed on most pain. In those with fibromyalgia, the gates are opened wider. "You see consistently -- in those with fibromyalgia -- very low pain threshold levels. Levels two or three times lower than that in healthy individuals," said Bradley.

Bradley thinks these two findings rule out a psychological base for fibromyalgia. He says his findings "are not just artefacts of psychiatric ailments." "Now that we know there are physical abnormalities in a wide variety of people with this disorder," said Bradley, "we can focus our research to determine why [they occur].... This may be a lead in developing treatments for this painful disorder."

He says the next step is watching brain blood flow in healthy people and comparing it to the results in fibromyalgic subjects. These tests will be conducted using magnetic resonance imaging (MRI) and a computerized brain-scan technique called Single Photon Emission Computed Tomography (SPECT).

"We have preliminary evidence that in healthy people, there's greater activation of blood flow as they respond to pain stimuli," said Bradley. He says his team will also look at a possible common origin between fibromyalgia and another syndrome with unexplained symptoms of tiredness and achiness -- Chronic Fatigue Syndrome.

Bradley presented his findings at the American College of Rheumatology national meeting in Orlando.