Fibromyalgia: More men diagnosed with new critiera

Fibromyalgia is a combination of pain and the presence of more than one diagnosis, also known as comorbid ailments. These ailments can include fatigue, sleep problems, cognitive dysfunction, depressive symptoms, irritable bowel syndrome or headaches.

The vast majority of patients diagnosed with fibromyalgia to date have been women. New criteria for the diagnosis translated to Norwegian in 2016, fibromyalgia survey diagnostic criteria, aim to ensure that more people receive the correct diagnosis and treatment.

Norwegian researchers have now investigated these new translated criteria. The results show that they have a big impact on who is diagnosed with fibromyalgia, according to the independent health news magazine Dagens Medisin, which first mentioned the study.

“We feel positive about the new criteria and hope they’ll make the disease a little more recognized among doctors,” says Elisabeth W. Thomassen, director of the Norwegian Fibromyalgia Association.

Diagnostic form introduced

The researchers looked at 120 people, all of whom were diagnosed with fibromyalgia based on the old criteria, as well as 62 controls where fibromyalgia was not suspected. All of them responded to a Norwegian version of the fibromyalgia survey questionnaire, and were then assessed according to the old regime, the ACR1990 fibromyalgia criteria .

The biggest difference between the old diagnostic criteria and the new ones introduced in 2016 is that doctors will no longer only look for certain inflamed points on the body, called “tender points,” to make a diagnosis. From now on, a survey questionnaire will be used to find out what symptoms the patient has.

The symptoms can include fatigue, difficulty concentrating, sleep problems, headaches, depressive symptoms and irritable bowel syndrome, Dagens Medisin writes.

“The old way of thinking was that fibromyalgia was an inflammation or a rheumatic disease without inflammation. Now we believe it’s a hypersensitivity in the nervous system that makes it difficult to regulate pain,” Egil A. Fors tells Dagens Medisin.

Fors is a professor in NTNU’s Department of Public Health and Nursing and one of the researchers behind the study.

More men now being diagnosed

One change that separates the old and new criteria is who gets the diagnosis. Using the old criteria, nine out of ten people diagnosed with fibromyalgia were women.

“With the new criteria, the balance is two to one. It seems reasonable to believe that a lot of men are walking around with symptoms under the guise of other illnesses,” says Fors.

In addition, fibromyalgia has acquired the status of being a “woman's disease,” says Thomassen from the Fibromyalgia Association.

“Doctors haven’t wanted to diagnose fibromyalgia in men for that reason. But actually quite a few men also have the diagnosis today,” she says.

The Norwegian Fibromyalgia Association estimates that more than 160 000 Norwegians have the diagnosis, based on figures from the Trøndelag Health Study (HUNT).

Objective measurements

Fibromyalgia has long been considered a somewhat intangible diagnosis. But researchers now believe that objective measurements can characterize patients with fibromyalgia. Fors believes this has led to greater recognition of the diagnosis.

One of the criteria is the presence of a substance in the spinal fluid that surrounds the spine. The substance is called substanceP and regulates pain. People with fibromyalgia have an increased incidence of substanceP.

According to Fors, doctors can also measure hypersensitivity in the nervous system in people with fibromyalgia.

“For example, if you inflict pain in the left hand of a healthy person, the pain will disappear if you expose another area, such as the right ankle, with greater pain. This is called ‘conditioned pain modulation’ or CPM. This doesn’t happen in fibromyalgia patients, who have reduced CPM compared to healthy controls,” Fors tells Dagens Medisin.

Easier for patients and doctors now

The diagnostic form for the various ailments should simplify the diagnosing for doctors so they can provide the right treatment, according to the researchers behind the study.

Thomassen agrees and says, “Patients are able to think through the questions in advance and don’t have to answer on the spur of the moment. I think the form will make it easier for doctors and patients.”

She also hopes that the new diagnostic criteria will make fibromyalgia less fuzzy and diffuse.

“I really hope the process improves. But it’s still fuzzy because no blood tests or other tests exist to test for fibromyalgia. Doctors only have the compiled criteria to base their diagnosis on. There aren’t any blood tests to confirm this,” she says. However, it seems that the criteria are at least becoming more tangible now.

Blood test trials

In 2019, American researchers believed that they had found a blood test that could be used to diagnose fibromyalgia. Fors commented on the results in a forskning.no article and expressed scepticism.

“We don’t have to reject the study completely, but it hasn’t been mentioned in the professional community,” he said at that time.

However, he thinks the results were exciting.

“This study didn’t use a large amount of sample material, but the findings are promising. It will be exciting if they manage to repeat these findings with a larger sample,” Fors said.

Although the new diagnostic criteria do not include a blood test, Fors believes that the new system is a good instrument. He also says that most doctors find that the criteria work.

Translated by: Ingrid P. Nuse

Reference:

Fors, E. A., Wensaas, K., Eide, H., Jaatun, E. A., Clauw, D. J., Wolfe, F., & Helvik, A. (2020). Fibromyalgia 2016 criteria and assessments: comprehensive validation in a Norwegian population. Scandinavian Journal of Pain.

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Read the Norwegian version of this article on forskning.no