Fibromyalgia, a chronic disease that affects approximately 1.6% of the French population, remains largely misunderstood despite its prevalence. Indeed, the precise origins of this disorder remain uncertain. Various hypotheses have gradually been formulated to try to explain it: psychological trauma, dysfunctions of the central nervous system , sleep disorders , etc. To try to remedy this lack of understanding, studies are regularly conducted.
Thanks to these research approaches, the first elements of an answer are finally appearing: a direct link has just been established between the intestinal microbiome and fibromyalgia. This discovery marks a notable turning point in the understanding of this pathology and therefore in the treatment that results from it.
Current state of knowledge on the microbiome
The microbiome is defined as the set of microorganisms (viruses, parasites, bacteria and fungi) living in symbiosis with their host in a given environment. This is personal: each individual has their own composition of microorganisms . These evolve throughout life depending on various elements such as lifestyle, eating habits or taking certain medications.
The microbiome has a significant impact on our health. For example, a
Dysbiosis (i.e. an imbalance of the intestinal microbiota) may be the origin
of certain pathologies.
For example, studies have shown that changes in the microbiome may be associated with inflammatory diseases such as IBD (inflammatory bowel disease), as well as neurodegenerative, neurobehavioral, and neuropsychiatric disorders. These advances have opened the door to new hypotheses and thinking about the involvement of the microbiome in other diseases.
In 2019, and for the first time, a team of researchers managed to establish a direct link between this chronic disease and certain changes in the intestinal microbiome . Based on these results, the same professionals continued their investigations with a new study to try to learn more.
A reliable diagnosis now possible?
The second study, published in 2022 in the medical journal Pain, provides solid results on the manifestations of fibromyalgia. Two major discoveries were thus made.
The discovery of a biological signature of fibromyalgia
First, researchers found that people with fibromyalgia have significant biological differences compared to healthy people. These include differences in:
- The constitution of the intestinal microbiome. The quantity and variety of bacteria responsible for bile metabolism are different (and particularly marked) in people with fibromyalgia. These have also been clearly identified.
- Blood bile acid levels. Women with fibromyalgia have significantly altered serum concentrations of secondary bile acids compared to healthy women. The bile acids involved could also be identified.
The observed variations are sufficiently clear and distinct to be used as a biological marker, which may give hope for the development of a precise and concrete tool for the diagnosis of fibromyalgia.
The ability to assess and severity of symptoms
At the same time, the researchers were able to link certain biological alterations to the severity of fibromyalgia symptoms . Specifically, they demonstrated that the concentration of a secondary bile acid was on average five times lower in patients with fibromyalgia than in healthy people.
This change in concentration has been correlated with several symptoms of fibromyalgia such as sleep disturbances, pain, fatigue and cognitive problems. Variations in the gut microbiome and bile acids could therefore have a direct impact on the severity of symptoms.
Tracks away
Some of the differences observed in the composition of the patients' microbiome and in the bacteria metabolizing bile were likely attributable to fibromyalgia, and not to other individual or environmental factors as previously suggested.
It is not uncommon for people with fibromyalgia to also suffer from other conditions such as irritable bowel syndrome or depressive disorders. However, this latest study has shown that the changes found in bile acids are not associated with these other conditions.
In addition, some analyses conducted during the study have refuted the hypothesis that diet can play a role in fibromyalgia symptoms. Despite the impact of diet on the balance of the intestinal microbiome, and the importance of maintaining a healthy lifestyle, no significant correlation was observed between dietary habits and fibromyalgia symptoms. These results confirm the idea that this pathology has independent and specific causes.
Demonstrating that fibromyalgia and its symptoms are not simply due to external factors or associated diseases can help to provide legitimacy. Indeed, affirming that it is a distinct pathology could contribute to the recognition of this disease and to the fight against preconceived ideas.
Encouraging prospects
To date, the process of diagnosing fibromyalgia is still long and difficult. Doctors must exclude several other pathologies with similar symptoms, which makes the process all the more complex. This delay is particularly trying for patients given the presence of symptoms (such as intense pain) and their impact on quality of life.
The prospect of a new diagnostic method coming soon is therefore a real source of hope and progress. Theoretically, fibromyalgia could be diagnosed with an accuracy of more than 90% by measuring the presence of six secondary bile acids. In addition, biologically assessing the severity of the disease seems an increasingly realistic idea.
Another promising factor is the use of artificial intelligence (AI) in the medical field. By integrating biological analyses with AI algorithms, it becomes possible to process and interpret massive amounts of data, thus increasing the accuracy of diagnoses and treatments. However, although these discoveries open new perspectives, further studies are needed before their widespread adoption in clinical practice.
