The cause of fibromyalgia is unknown. There are indications that an injury, infection or illness may trigger the condition. There are also indications that hereditary factors are involved in the development of fibromyalgia as sometimes it occurs in several members of one family.
It is thought that fibromyalgia may be due to a malfunction in the way the central nervous system processes pain signals. This leads to people with fibromyalgia experiencing pain from sensations that other people might perceive only as discomfort.
Two brain chemicals, Serotonin and Substance P, are thought to play a role in the condition. Serotonin is a neurotransmitter (a chemical that enables the transmission of nerve impulses) that influences mood, appetite, pain perception, sexual function, anxiety, temperature control and sleep. Studies have indicated that levels of this chemical are lower than usual in people with fibromyalgia.
Substance P, another neurotransmitter, is involved in transmitting pain sensations to the brain and also regulates the way we perceive pain. Some studies have found substantially elevated levels of this substance in people with fibromyalgia.
Signs and symptoms
The one symptom experienced by everyone with fibromyalgia is pain. This pain can be described in various ways, such as an ache, a sharp pain, a throbbing or a burning feeling. The pain is felt throughout the body and on both sides of the body. The pain can move from one part of the body to another. The amount of pain experienced can vary throughout the day and can also worsen with a change in weather, increase in stress, noise, activity and lack of sleep.
Stiffness of muscles and joints is most noticeable in the morning and after a period of rest. This can interfere with work and daily activities such as driving. Keeping moving is the best way to prevent stiffness. If a person has to sit for long periods, he or she can reduce stiffness by regularly getting up to move around and stretch.
Many people with fibromyalgia experience sleep problems. There are a number of stages of normal sleep ranging from light to deep sleep. It seems that people with fibromyalgia often lack the deep restorative stages of sleep and often wake feeling unrefreshed. Over half of people with fibromyalgia experience symptoms such as irritability, forgetfulness, lack of concentration, mood changes, anxiety and depression.
Other symptoms that can be experienced by people with fibromyalgia include:
- Migraine and tension headaches
- Recurrent abdominal pain
- Difficulty swallowing
- Irritable bladder leading to frequent or painful urination
- Numbness and tingling of the extremities
- Dry eyes and mouth.
Doctors use certain criteria to help make a diagnosis. Most people with fibromyalgia have symptoms of widespread pain not explained by other conditions, and tenderness in at least 11 out of 18 tender points (shown in the diagram below). However, some people may still have fibromyalgia even without these symptoms. Other indicators doctors will look for include:
- Normal blood tests
- Chronic fatigue
- Sleep disturbances
- Skeletal pain (mainly in the neck and back).
Rest and sleep
Stress reduction and relaxation
Low doses of tricyclic antidepressants, such as amitriptyline or nortriptyline, can be helpful in relieving the pain of fibromyalgia. These medications also improve quality of sleep and can help address the imbalance of neurotransmitters in the pain conduction pathways. While these medications help some people with fibromyalgia, they are not effective in all cases.
Arthritis New Zealand
Phone: 0800 663 463
ReferencesArthritis New Zealand (2011) Fibromyalgia. Arthritis New Zealand, Wellington.
Shiel, W. C., (2007) Fibromyalgia. MedicineNet, Inc. San Clemente. CA. http://www.medicinenet.com/fibromyalgia/article.htm