Pain of Fibromyalgia Linked to Central Nervous System Disorder

New research indicates that the chronic pain condition fibromyalgia is linked to central nervous system abnormalities evidenced by patients' elevated sensitivity to auditory and pressure sensations.

The study was conducted by researchers at the University of MIchigan and is published in The Journal of Pain.

The researchers studied 31 fibromyalgia patients to determine if there is a global central nervous system problem underlying sensory processing in fibromyalgia patients.

From previous studies it has become clear that people with fibromyalgia process stimuli differently to healthy individuals. It is thought that the end result of this is that a small amount of pressure on the skin is felt as pain by a fibromyalgia patient where it would be felt as a light touch to someone who is healthy. It is not just touch which can trigger symptoms in fibromyalgia however, stimuli such as sound also seem to be amplified meaning it is hard for patients to feel well in noisy environment

The Michigan researchers noted that few studies have looked at different stimuli in consistent ways and levels of intensity to measure pain sensitivities in the condition. In this study then, fibromyalgia patients and healthy subjects were exposed to random auditory and pressure stimuli.

In keeping with findings from previous studies, the researchers found that fibromyalgia patients showed greater sensitivity to auditory tones and reported higher sensitivity to everyday sounds. Additionally, significant associations were observed between the auditory and pressure responses which support the theory that such abnormalities maybe related to a common pathophysiological mechanism.

They also confirmed that noise is amplified in fibromyalgia subjects. The patients perceived auditory stimuli to be of the same intensity as felt by healthy subjects, even though the actual intensity levels they were being exposed to were lower.

The researchers concluded that their findings demonstrate fibromyalgia is associated with a central nervous deficit in sensory processing. They say further research is needed to examine mechanisms governing these perceptual abnormalities.