# Fibro Pain: Evidence of its physiological basis, an article.



## Susan Purry (Nov 6, 2001)

*Physiologic Factors Involved in Fibromyalgia, Contradicting Psychogenic Attribution*http://www.medscape.com/viewarticle/436963?srcmp=rheu-062102&WebLogicSession=PRoKWcripd3MhzwooKsf21tJJc9VbvJBR9S9ojiaZUit1QKdUE9N|1761235351179314329/-1408233355/6/7001/7001/ 7002/7://http://www.medscape.com/viewarticle...01/7001/ 7002/7://http://www.medscape.com/viewarticle...01/7001/ 7002/7 002/7001/-1


> quote:NEW YORK (Reuters Health) Jun 19 - *Functional magnetic resonance imaging (fMRI) and neuroendocrine studies of people with fibromyalgia reinforce the notion that altered responses to pain and exercise are physiologically based. "When patients with fibromyalgia tell us that they're tender, that they're experiencing pain at a much lower [pressure] level than people without the condition, they are in fact experiencing that pain," *Dr. Daniel J. Clauw, of the University of Michigan Medical Center in Ann Arbor, told Reuters Health. Two reports in the May issue of Arthritis and Rheumatism are the *"first neurobiological evidence of the veracity of their pain," *he added, referring to another study in which responses to exercise were measured in fibromyalgia patients. Dr. Clauw and colleagues studied 16 people who had been diagnosed with fibromyalgia and 16 healthy control subjects. All underwent fMRI while a piston-controlled device applied precisely calibrated pressure to the base of their left thumbnail. Fibromyalgia patients reported pain at about half the level of pressure that caused the same feelings of pain among the healthy controls (p<0.005). When all study participants received the same level of mild pressure, which was painful to the fibromyalgia patients, 12 brain areas were activated in patients with fibromyalgia, but only two were activated in the control group. Increased blood flow--a surrogate measure of nerve activity, according to Dr. Clauw--occurred in the primary and secondary somatosensory cortex, the insula, the putamen, and cerebellum. Moreover, pain in the control group activated regions in the thalamus, the anterior cingulate cortex and other regions involved in motor responses, which were not activated in the patient group. The investigators attribute these differences to "tonic inhibition maintained by persistent excitatory input associated with ongoing and spontaneous pain" in fibromyalgia patients. Dr. Clauw said *the findings suggest that something is awry with the way the central nervous system processes painful stimuli in fibromyalgia patients, resulting in a lowered pain threshold. *Future research should be aimed at identifying the problem and working to develop better treatments, he added. In the second report, Dr. Robert M. Bennett and colleagues of the Oregon Health Sciences University in Portland showed that 20 female fibromyalgia patients exhibited reduced growth hormone and cortisol responses to an acute exercise stressor, compared with 10 healthy female control subjects (p=0.003). The growth hormone response was restored in the patients, but not increased in the control subjects, by administration of the potent cholinergic agent pyridostigmine bromide 1 hour before exercise. Dr. Bennett and his associates conclude that patients with fibromyalgia have an increased hypothalamic somatostatin tone. They would like to see if long-term treatment with pyridostigmine would improve growth hormone production in fibromyalgia. *Both studies imply that regulatory mechanisms localized to the central nervous system are altered in fibromyalgia,* note Drs. Clauw and Leslie J. Crofford, also of the University of Michigan, in an editorial. "Purely behavioral or psychological factors are not primarily responsible for the pain and tenderness seen in fibromyalgia," they assert. While behavioral factors likely play a role in symptom expression in many of these patients, resulting in poor role functioning, the commentators note that this phenomenon is similar for all rheumatic diseases. Arthritis Rheum 2002;46:1136-1138,1333-1350.


Forgive me for always highlighting bits of articles I post. It's not that I don't think people know what the important bits are, but that I recognise sometimes we don't have the energy to read all the article.


----------



## trbell (Nov 1, 2000)

interesting information, Susan, but I get confused by some of these things and the way they are worded since the thalamus and other things they mention are in the brain?tom


----------



## Ian (Apr 18, 1999)

There was something similar on www.immunesupport.com a couple of weeks ago - may even have been reporting the same research.Anyway, this is obviously very encouraging both for giving proof of patients' symptoms and in setting directions for future research.


----------

