Fibromyalgia (FM) is a condition that is characterized by widespread pain, fatigue and an increased pain response. Symptoms can include tingling of the skin, muscle spasms, weakness in the arms and legs, nerve pain, muscle twitching, bowel disturbances, chronic sleep disturbances, and more. So, what can cause such a widespread, whole body condition? Though the “cause” of FM is unknown, several hypotheses have emerged. Here is what we know:
1. The brains of FM patients: Structural and functional differences have been identified in the brains of FM vs. healthy individuals. What is unclear is whether these identifiable brain changes cause the FM symptoms or are the result of an unknown cause. Some experts have reported that the abnormal brain findings may be the result of childhood stress, or prolonged, severe stress at any time in life. An area commonly affected is called the hippocampus, which plays a crucial role in maintaining cognitive functions, sleep regulation, and pain perception.
2. Lower pain threshold: Due to an increased reactivity of pain-sensitive nerve cells in the spinal cord and brain (called “central sensitization), FM patients feel pain sooner and worse than non-FM subjects.
3. Genetic predisposition: It has been reported that FM is often found in multiple family members. This genetic propensity also includes other conditions that often co-exist in FM patients such as chronic fatigue syndrome, irritable bowel syndrome (IBS), and depression.
4. Stress & lifestyle: Stress by itself may be an important cause of FM. It is not uncommon to develop FM after suffering from post-traumatic stress disorder. An association between physical and sexual abuse both in childhood and adulthood has also been identified. Poor lifestyle issues including smoking, obesity, and lack of physical activity increase the risk of developing FM.
5. Dopamine dysfunction: Dopamine is a chemical needed for neurotransmission and plays a role in pain perception. It is also connected to the development of restless leg syndrome (RLS), which is a frequent complaint of FM patients. Medications found effective for RLS such as pramipexole (also used for the treatment of Parkinson’s disease) can be helpful for some FM patients.
6. Abnormal serotonin metabolism: Another neurotransmitter, serotonin, regulates sleep patterns, mood, concentration, and pain and can be involved in causing FM. Decreases in other neurotransmitters (especially norepinephrine), when combined with serotonin depletion, can especially cause FM (more so in women than men). Hence, medications like duloxetine (Cympalta) originally used to treat depression and painful diabetic neuropathy, have been found to help FM patients, especially women.
7. Deficient growth hormone (GH) secretion: Abnormal levels of GH have been found in FM patients, but studies report mixed results when treating FM with GH.
8. Psychological factors: Strong evidence supports the association of FM and depression. Similarities include neuroendocrine abnormalities, psychological characteristics, physical symptoms and similar treatment benefits using the same approach (medication, counciling, etc.).
9. Physical Trauma: Trauma can increase the risk of FM. One report found a direct association with neck trauma and increased risk of developing FM.
10. Small bowel bacterial overgrowth: This can contribute to FM and may explain the association with IBS. The autoimmune response to the presence of bacteria resulting in FM symptoms has been hypothesized in these cases.
CONCLUSION: As previously stated, it is clear that a “team” of providers is needed to effectively treat FM. We’d be honored to be part of your team!