Does Fibromyalgia Still Have a Credibility Problem?

Fibromyalgia is a condition characterized by generalized pain, or high sensitivity to pain, chronic fatigue, lack of mental concentration, and mood and sleep disorders. Although physicians are continuing to develop a better understanding of it, it remains as one of the most difficult conditions to diagnose and treat.

Fibromyalgia has long been the subject of controversies, as there is a lack of specific tests or physical changes that other painful and inflammatory conditions have. Because of this, patients believe that their condition is not understood as well as it should be.

One of the earliest attempts to put an end to the controversy was by the American College of Rheumatology, which came up with one of the first diagnostic criteria for fibromyalgia in the early 1990's, and since then a lot has changed.

Even after more than a couple of decades of a standardized diagnostic criteria, understanding fibromyalgia is still very challenging. For one, the disease is presented very differently in each person. Even the triggers vary significantly among patients, for some it could be a rheumatic disease while for others it may be due to stress.

One of the latest attempts to improve the diagnosis and understanding of the disease has been the vision of diagnostic criteria by American College of Rheumatology in 2016. There have been several changes in this latest review of diagnostic criteria, like the creation of a single pain estimation criteria for both the patient and physician, or as per the latest understanding, the presence of other painful conditions that would exclude the diagnosis of fibromyalgia. But, is this really enough to go on?

The central component of fibromyalgia

One of the most significant challenges in understanding fibromyalgia has been due to the lack of cause for the widespread and chronic pain. This has led many physicians to try and find out if there is any neuromuscular disorders present in those living with fibromyalgia.

Now, it is well accepted that one of the primary mechanisms of fibromyalgia is central sensitization. In various experiments, helped by the latest neuroimaging techniques, it has been demonstrated that the brain responds more than usual to pain stimuli. In fact, while there is an altered resting state and changes in connectivity, there are morphological changes in the brain. Some research has noted changes in the grey matter with various brain areas including the hippocampis, post-central gyri, amygdala, superior frontal, insular, and anterior cingulate.

There is mounting evidence in favor of neurochemical changes in the brain, including a decrease in µ-opioid receptors, increased insular glutamate, and reduced GABA, as compared with healthy people. Further research has indicated changes in levels of neurotransmitters involved in pain transmission like an increase in the concentration of substance P, glutamate, nerve growth factor, while a decrease in the levels of serotonin, dopamine, norepinephrine, and GABA. There are also changes in neuroplasticity, causing lost concentration and brain fog.