Our Medical Advisor Dr Gregor Purdie considers the overlap between M.E. and Fibromyalgia.
“My doctor talked in detail about Fibromyalgia at the same time as M.E. when he was coming to a diagnosis. He is sure it’s M.E. for me but there have been many times I have wondered. The pain and mobility are my hardest symptoms.” Sammy
Dr Gregor Purdie writes:
In my clinical practice, I have become increasingly of the opinion that M.E. and Fibromyalgia could well be part of a spectrum of illness. Some people have fatigue as the principal symptom and therefore would be at the M.E. end of the spectrum. With fibromyalgia, pain is the principal symptom. When going through the Canadian Guidelines rating scale with patients, it became increasingly obvious that after fatigue, including post-exertional fatigue, widespread pain was the next most debilitating problem.
Looking at the symptom list for Fibromyalgia, I note the great overlap in symptoms. Fatigue is a recognised symptom of Fibromyalgia. People with Fibromyalgia are assessed on the extent of problems they have with sleep disturbance. Cognitive problems are called “fibro fog.”
People with Fibromyalgia also suffer from headaches, bowel symptoms and dizziness. There can be problems with temperature regulation such as feeling too hot or too cold. Restless legs syndrome is noted in Fibromyalgia, and I have seen patients with M.E. who complain of this problem as well.
One can therefore see that there are symptoms that are common to both illnesses. Could there be some tie up between the two?
Causes of Fibromyalgia are noted to be infection, an injury, child birth or an operation. An extremely stressful event such as bereavement can also trigger the condition. There is again overlap with the triggers for M.E.
A paper has just been published exploring this whole question [McKay, PG. et al. 2019. CFS/M.E. and Fibromyalgia: the foundation of a relationship. British Journal of Pain]. It asked people with M.E. and people with Fibromyalgia to complete questionnaires specific to their illness, as well as more general questionnaires looking at the symptoms identified.
Some interesting outcomes include that some people with M.E. have pain symptoms so severe that they could be classed as severe Fibromyalgia. People with Fibromyalgia can suffer a high level of fatigue. People with both illnesses suffer from sleep disturbance. Both groups can suffer from co-morbid anxiety and depression, with this being more pronounced in people with Fibromyalgia.
M.E. is classed as a neurological illness by the World Health Organisation. In the UK, no single specialty covers this illness, with Infectious Diseases, Immunology and Neurology departments involved. Fibromyalgia comes under the remit of Rheumatology. Each condition has developed its own diagnostic criteria. Therefore the only doctors who would be liable to see people with either condition would be a GP.
When a GP is faced with a patient complaining of fatigue and pain in particular, it can be very difficult to differentiate between the two, as noted by Sammy; I would bear this out from my own clinical practice.
As with M.E., there is no specific treatment for Fibromyalgia. Medication is prescribed to help manage the pain and antidepressants are used as an adjunct in helping to relieve the pain.
There has been much debate on the use of Vitamin D. Some are advised to spend time in sunnier climes; I would interpret this as a way of maximising Vitamin D levels. But this might not be right for someone with M.E., and any management must be tailored to each individual patient.
In conclusion, there would appear to be really quite an overlap between the conditions. There are people at the pure M.E. end of the spectrum with others are the pure Fibromyalgia end. Many people, especially from a GP perspective, fall somewhere along a continuum in-between.
Neither illness has a specific diagnostic test; instead, diagnosis is made after listening to the person’s story, making a physical examination, and after any other diagnosis has been ruled out. Neither condition has a specific treatment, though many of the medications used to relieve symptoms are common to both illnesses. This is an area where further research is required.