Researchers trying to fathom the causes of fibromyalgia

September 14, 2018 by Kevin Davies, Jessica Eccles And Neil Harrison, The Conversation
Credit: TierneyMJ/

Fibromyalgia is something of a mystery. It can't be detected with scans or blood tests, yet it causes lifelong pain for millions of people.

The disease mainly affects women (about 75-90 percent of cases), causing pain all over the body. Because not all healthcare professionals are adept at identifying and diagnosing fibromyalgia, reported rates of the condition vary greatly from country to country. In China, it affects only 0.8 percent of people, in France around 1.5 percent, in Canada 3.3 percent, and in Turkey 8.8 percent. Estimates in the US range from 2.2 percent to 6.4 percent, and in Russia, about 2 percent of the population is affected.

People with the condition are often diagnosed if they have longstanding muscle pain, bone or joint pain and fatigue. Fibromyalgia can also cause insomnia, "brain fog", some symptoms of depression or anxiety, as well as a range of other complaints, including and headache. Many patients are also hypermobile ("double-jointed"), and there is some overlap with chronic fatigue syndrome (also known as ME).

Guidelines from the American College of Rheumatology make it clear that the diagnosis should be made using defined criteria based on the "widespread pain index" (which scores the number of painful regions out of 19) coupled with a symptom severity scale. The diagnosis also takes fatigue, generalised pain, unrefreshing sleep and cognitive symptoms into account. It doesn't matter if the patient has another rheumatic disease, they can still be diagnosed with fibromyalgia.

The scoring system, recommended by the American College of Rheumatology, is often used in clinical trials, but in the clinic, most doctors rely on detecting tender points in specific places and on excluding other medical conditions, including rheumatic conditions. Unlike say, rheumatoid arthritis or lupus, the tests do not show clear evidence of inflammation or autoimmunity (when the body's immune system attacks itself) and scans are normal.

The lack of inflammation or structural abnormality in muscles or joints – aside from making diagnosis difficult – is the main reason there are no widely accepted or effective treatments. In rheumatic diseases, where we understand the mechanisms that underlie the condition, we have the most effective treatments. In rheumatoid arthritis, for example, we know that much of the inflammation is caused by a cell-signalling protein (cytokine) called and that blocking the activity of this protein switches off the disease in most patients.

Researchers trying to fathom the causes of fibromyalgia
Many people with fibromyalgia are hypermobile ( MatthewThomasWxm/Wikimedia Commons, CC BY-SA

A number of possible mechanisms have been proposed in fibromyalgia, including abnormal muscle metabolism, reduced levels of steroid hormones such as cortisol, or abnormal small nerve fibres. But these abnormalities aren't found in all patients with the condition. As such, they can't be used as part of a diagnostic test, nor can they help develop treatments.

Some experts have suggested that fibromyalgia may be related to abnormalities in the autonomic nervous system – the part of the nervous system that controls bodily functions, such as and blood pressure – and how the brain responds to pain signals and reacts to external stressors (such as infections). But there is currently no hard evidence to back up this theory.

Looking for clues

To fill in some of the gaps in our knowledge about this devastating condition, our research team at Brighton and Sussex Medical School is investigating the potential role of the autonomic nervous system and inflammation in fibromyalgia and chronic fatigue syndrome.

For our study, we have two groups of patients: one with pain as the main symptom and the other with fatigue as the main symptom. We also have matched controls – people without the disease, but otherwise similar characteristics – to make meaningful comparisons.

The study is in two parts. First, we will test the patients' autonomic nervous system using a tilt-table. This involves tilting the person head downwards to see how well their body adapts to this change in posture by changing heart rate and (both of which are monitored during the test).

Researchers trying to fathom the causes of fibromyalgia
A tilt-table test. Credit: Blamb/

Second, we will stimulate patients' immune systems with a typhoid vaccine (the normal type used in travellers) and perform magnetic resonance brain scans to look for changes in blood flow and also measure the levels of "inflammatory mediators" (the chemicals the body produces in response to stimuli of this type), to see whether these are higher in the fibromyalgia patients.

Our study should, for the first time, help us to address the question of whether there really is an abnormal brain response to inflammation or infection in these patient groups and enable us to explore the relationship between the abnormal functioning of the autonomic nervous system and and .

Fibromyalgia rarely goes away and treatment options are limited. Only by developing a proper understanding of the disease processes underlying this condition will doctors be able to make a clear, positive diagnosis, and most importantly, offer effective therapy.

Explore further: Link between DNA and chronic widespread joint pain

Related Stories

Link between DNA and chronic widespread joint pain

November 11, 2016
Scientists at King's College London, funded by the charity Arthritis Research UK, have found a link between changes in marks on the outside of DNA (epigenetics) and chronic widespread joint pain, one of the main symptoms ...

Screening women veterans with fibromyalgia for childhood abuse may improve treatment

August 8, 2018
A new study has shown that women Veterans being treated for fibromyalgia exhibit high rates of childhood abuse.

New research could lead to a blood test for common pain syndrome fibromyalgia

May 12, 2015
New UK research could lead to a blood test to diagnose the common pain condition, fibromyalgia.

Men with fibromyalgia often go undiagnosed, Mayo Clinic study suggests

December 19, 2012
Fibromyalgia is a complex illness to diagnose and to treat. There is not yet a diagnostic test to establish that someone has it, there is no cure and many fibromyalgia symptoms—pain, fatigue, problems sleeping and memory ...

Fibromyalgia and the role of brain connectivity in pain inhibition

October 1, 2014
The cause of fibromyalgia, a chronic pain syndrome is not known. However, the results of a new study that compares brain activity in individuals with and without fibromyalgia indicate that decreased connectivity between pain-related ...

Weather conditions do not affect fibromyalgia pain or fatigue

June 4, 2013
Dutch researchers report that weather conditions including temperature, sunshine, and precipitation have no impact on fibromyalgia symptoms in female patients. Results published in Arthritis Care & Research, a journal of ...

Recommended for you

Antibiotic prescribing influenced by team dynamics within hospitals

November 15, 2018
Antibiotic prescribing by doctors is influenced by team dynamics and cultures within hospitals.

Discovery suggests new route to fight infection, disease

November 14, 2018
New research reveals how a single protein interferes with the immune system when exposed to the bacterium that causes Legionnaires' disease, findings that could have broad implications for development of medicines to fight ...

Zika may hijack mother-fetus immunity route

November 14, 2018
To cross the placenta, Zika virus may hijack the route by which acquired immunity is transferred from mother to fetus, new research suggests.

Maternally acquired Zika immunity can increase dengue disease severity in mouse pups

November 14, 2018
To say that the immune system is complex is an understatement: an immune response protective in one context can turn deadly over time, as evidenced by numerous epidemiological studies on dengue infection, spanning multiple ...

New research aims to help improve uptake of hepatitis C testing

November 14, 2018
New research published in Scientific Reports shows persisting fears about HIV infection may impact testing uptake for the hepatitis C Virus (HCV).

Synthetic DNA-delivered antibodies protect against Ebola in preclinical studies

November 13, 2018
Scientists at The Wistar Institute and collaborators have successfully engineered novel DNA-encoded monoclonal antibodies (DMAbs) targeting Zaire Ebolavirus that were effective in preclinical models. Study results, published ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Oct 23, 2018
Fibromyalgia pain can be frustrating. I had Fibromyalgia for at least 7 years. My initial symptoms were fatigue and lower back pain which were manageable, In 2015 it really kicked in with widespread pain, soreness, sleeplessness, inflammation and extreme fatigue. I tried so many medications and supplements to get some relief nothing worked, until last year, i learnt about FIBROMYALGIA SUCCESSFUL TREATMENT from Rich Herbs Foundation (RHF). I was skeptical it would help, but i gave the treatment a try. Few weeks into the treatment, I went back to work feeling good and my legs weren't hurting, i almost forgot how long it has been since I felt this good and normal. The pain was 95 percent gone on my legs and lower back, the inflammation was gone too. Visit RHF we b page ww w. richherbsfoundation. c om. Here I am 11 months after the treatment and i still feel good and active.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.