Most people with fibromyalgia (FMS) and chronic fatigue syndrome (ME/CFS) also have a few other illnesses, and both research and observation have long shown that specific illnesses tend to accompany FMS and ME/CFS.
In a review of FMS literature, noted researcher Dr. Muhammed Yunus presents evidence for the cluster of illnesses we generally see all having a key feature in common: central sensitization (CS). As a group, they're called central sensitivity syndromes (CSS), although some of the conditions are classified as diseases.
The many illnesses Yunus identifies as CSS include:
- Chronic fatigue syndrome
- Irritable bowel syndrome
- TMD/TMJ (temporomadibular disorder)
- Restless legs syndrome
- Rheumatoid arthritis
- Systemic lupus
- Ankylosing spondylitis
- Inflammatory bowel disease
- Carpal tunnel disorder
- Myofascial pain syndrome
- Multiple chemical sensitivity
- Post-traumatic stress disorder
- Gulf War illness
- Interstitial cystitis
Yunus says it's important for doctors to be aware of these overlaps so they can accurately diagnose and manage FMS when it accompanies other conditions.
What is Central Sensitization?
Usually when we hear about sensitization or sensitivity, it has to do with an allergy. In an allergy, the body becomes sensitive to a particular substance and thereafter reacts inappropriately to it.
The central part of CS refers to the central nervous system, which is made up of the brain and spinal column. The central nervous system, in these conditions, because sensitized to "noxious stimuli," which is basically any input that's unpleasant - pain, bright light, certain noises, etc. As with an allergy, the body begins to react inappropriately to that input.
As a result, what should be mild discomfort becomes pain, an obnoxious noise may trigger pain or anxiety, and light pressure from a waistband may cause a burning feeling on the skin and a deep ache in the muscles and connective tissues.
Yunus says evidence supports the theory that CS is a causal factor in these illnesses and the reason that they so often occur together. (Causal factor means that it is one of many causes that come together and not the sole cause.) Having one CSS predisposes you to the others.
I can see CS at work in my life from an early age. I have myofascial pain syndrome, which I believe started with an accident at age 10 that jarred my entire spine and caused lasting muscle damage and, I'd eventually learn, multiple trigger points. I've had chronic pain since then.
In high school, I started having mild TMJ symptoms. In college, my job waiting tables lead to carpal tunnel disorder. I had severe gestational diabetes with both pregnancies.
Close relatives on my mother's side have/had diabetes, inflammatory bowel disease, interstitial cystitis, osteoarthritis and multiple chemical sensitivity. This is a good example of a genetic predisposition toward CS, which Yunus discusses.
Which CS conditions do you have? Which others are present in your family? Leave your comments below!
Learn more or join the conversation!
Photo © A.D.A.M.