Fibromyalgia - Causes 

The exact cause of fibromyalgia is unknown. Research into people with fibromyalgia has identified a number of changes in the way that their body functions. However, what causes these changes in the first place, and how exactly these cause fibromyalgia, is still not clear.

The changes that have been noticed in people with fibromyalgia include:

• disturbed pain messages
• low levels of hormones
• sleep problems

These are explained in more detail below.

Disturbed pain messages

One of the most likely causes of fibromyalgia is a problem with the way that pain messages are carried and received in your body.

The central nervous system (brain, spinal cord and nerves) transmits information all over your body through a network of specialised cells. In people with fibromyalgia, the way that pain messages are processed is disturbed. This may explain why fibromyalgia results in constant feelings of pain and extreme sensitivity to pain.

Low levels of hormones

People with fibromyalgia have been found to have lower-than-normal levels of the hormones serotonin, noradrenaline (also known as norepinephrine) and dopamine.

Low levels of these hormones may be a key factor in the cause of fibromyalgia, as they each control many of the processes in the body. For example:

• serotonin - this helps to regulate your moods, your appetite, and the way that you sleep
• noradrenaline - this contributes to your response in stressful situations
• dopamine - this helps to control your mood and behaviour, and the way that you learn

Sleep problems

It is possible that disturbed sleep patterns may be a cause of fibromyalgia, rather than just a symptom. Fibromyalgia can prevent you from sleeping deeply and cause fatigue (extreme tiredness). People with fibromyalgia who sleep badly also seem to feel more pain. This may suggest that the sleep problems in some way contribute to the other symptoms of fibromyalgia. 

Risk factors

There may be some risk factors that can either make fibromyalgia more likely, or act as a trigger for the condition. These include:

• physical trauma (damage to the body’s tissues)
• psychological trauma (an incident that causes emotional damage, such as the death of a loved one)
• a viral infection (such as hepatitis B, hepatitis C or HIV and AIDS)
• being depressed

Genetics

There may be a genetic link to fibromyalgia, with some people being more likely than others to develop the condition due to their genes (the units of genetic material inherited from their parents). If this is the case, a genetic predisposition (tendency) could explain why some people develop fibromyalgia after some sort of trigger.

Other conditions

There are several other conditions that can lead to fibromyalgia. In these cases, the condition is known as secondary fibromyalgia. Conditions that can cause fibromyalgia include:

• metabolic disturbances such as an underactive thyroid - when the thyroid gland does not produce enough of the thyroid hormone 
• inflammatory disorders such as rheumatoid arthritis - a condition that causes joint pain and stiffness 

It is also possible that there is no single cause of fibromyalgia, and that several of the above factors may combine to cause the condition.