New Dimensions in Fibromyalgia
and Classification of Fibromyalgia:
Where do we draw the line?
According to the 1990 American
College of Rheumatology criteria the diagnosis of fibromyalgia is based
on the history of widespread pain and the finding of 11 or more out of
18 designated tender point areas. Rheumatologists often encounter other
- Patients with widespread pain
who only have 6 or 7 tender points.
- Patients with regional pain
associated with sleep disturbance and multiple tender points.
- FM patients with widespread
pain and a few criteria tender points but multiple tender points in
- FM patients who have pain allover
and have the physical finding of allodynia.
- FM patients with associated
- FM patients who are fully functional
and patients who are very dysfunctional.
- FM patients with the findings
of neurally mediated hypotension.
- FM patients with an associated
growth hormone deficiency.
Epidemiological studies suggest
that fibromyalgia is at one end of a spectrum of chronic pain. This often
starts with regional pain syndromes and ends in severe, widespread intractable
pain with allodynia. Diagnosing fibromyalgia is analogous to diagnosing
hypertension; a critical question is: where do we draw the line? The salient
feature of fibromyalgia appears to be an abnormality of central pain processing.
A discussion of how this notion could be incorporated into diagnostic
criteria seems relevant. Consideration also needs to be given to providing
guidelines for the diagnosis of fibromyalgia subsets. For instance most
practitioners can readily differentiate between their patients with simple
fibromyalgia and those with complex fibromyalgia. The latter group usually
have significant psychosocial problems and are more likely to be dysfunctional.
Examples of possible subsets include: Major depression, widespread allodynia,
primary sleep disorders (e.g. sleep apnea), neurally mediated hypotension,
growth hormone deficiency, and a primary pain diagnosis (e.g. RA, SLE,
RSD, etc.). Fibromyalgia is more than a pain syndrome. The possibility
of developing a Multi-Axial classification, similar to that used in psychiatry
should be explored. Before any recommendations could be implemented a
multi-center study would have to be initiated to validate the proposed