The cause of fibromyalgia is unknown. Some researchers believe fibromyalgia originates with a problem in the nervous system, changing the way the brain and nerves process pain signals and increasing sensitivity to pain, cold, and other stimuli. Others believe that fibromyalgia begins with a disorder of the endocrine system, which produces hormones that regulate metabolism and respond to stress.

Scientists believe that both hereditary and environmental factors influence a person’s risk for developing fibromyalgia, but no one has identified why some people get fibromyalgia and some people don’t.

Risk Factors for Fibromyalgia

It is important to note that while science is good at finding correlations, or apparent relationships, between factors and disease, correlation does not prove that the factor causes the disease. Many risk factors for fibromyalgia have been identified and are being studied, but none have been pinpointed as the cause of fibromyalgia.

Hereditary Factors

Fibromyalgia does not appear to be directly inherited from parents in any clear genetic pattern. However, people with a family member who has fibromyalgia do have a higher risk for developing the disease themselves. In one small study, blood relatives of someone diagnosed with fibromyalgia had a 26 percent chance of developing the condition, while non-blood relatives had a 19 percent chance. Research to better understand hereditary predisposition for fibromyalgia is ongoing.

Women are much more likely than men to develop fibromyalgia – some researchers say the risk for women is twice as high, some say 10 times higher.

Fibromyalgia is more common among people diagnosed with an autoimmune condition such as lupus, rheumatoid arthritis (RA), or spondylitis. Some genes that predispose someone for autoimmunity may also pave the way for fibromyalgia.

Fibromyalgia is most commonly diagnosed in middle age but is sometimes diagnosed in children and older adults.

Environmental Factors

Researchers have identified a wide array of environmental factors linked to the development of fibromyalgia.

Studies have investigated specific viruses for links with fibromyalgia. Some scientists believe that one or more infections such as hepatitis C, Lyme disease, and HIV may cause genetic changes in some people, paving the way for the development of fibromyalgia. One study investigated links between receiving the vaccination for hepatitis B and developing fibromyalgia.

There are often links between psychological trauma and fibromyalgia. Post-traumatic stress disorder (PTSD) is a risk factor for the development of fibromyalgia symptoms. Depression and fibromyalgia are closely linked. Some people experience their first symptoms of fibromyalgia after an emotionally traumatic event such as divorce, an abusive relationship, or the death of a loved one. Automobile crashes and surgery, which can cause physical as well as emotional trauma, are other common triggers. There is evidence that a history of childhood abuse may increase risk for developing fibromyalgia, but more research is needed to confirm this link.

Fibromyalgia is commonly said to cause problems with sleep. However, some researchers theorize that sleep disturbances cause fibromyalgia symptoms of pain and fatigue to develop.

Obesity raises the risk of developing fibromyalgia.

Smoking may increase the likelihood of developing fibromyalgia and worsen chronic pain.

Condition Guide

• Fibromyalgia – An Overview
• Fibromyalgia – The Path to Diagnosis
• Symptoms of Fibromyalgia
• Treatments for Fibromyalgia
• What Causes Fibromyalgia?