Abuse and fibromyalgia
(Dr. Carol Burckhardt)

There is an increasing interest in the role of childhood physical and sexual abuse as a cause of fibromyalgia (FM). Beginning with two articles published simultaneously in Arthritis and Rheumatism, the major research journal of the American College of Rheumatology, the debate over this relationship has grown hot at times as researchers and clinicians have struggled with both the data and their biases.

For openers, no one, for the most part, denies that abuse occurs. Survey after survey confirms that a proportion of the adult population, both men and women, has been abused during childhood. While percentages vary by type of sample, in other words, community samples tend to have lower percentages than clinical samples, the rates of sexual abuse range from 10% all the way up to 80-90% in some groups (gastroesophageal reflux disease and irritable bowel syndrome). Physical abuse percentages may be even higher depending on how the abuse is measured.

For the purposes of this essay, I will limit the discussion to sexual abuse, primarily because it is generally recognized as the type of abuse that produces the most long-standing sequelae. It is also the type of abuse for which there are now standardized instruments for measurement, the most well-known of which is part of the National Population Survey of Canada. The studies of FM patients have all used this survey. That is an important point because one of the ways some people use to discredit a study is to say that the instruments used to measure something are not reliable or valid. They can’t say that about any of the studies that have been published so far on FM and sexual abuse or those that have been completed and are soon to be published.

First I’ll summarize the findings of the two studies that have been published. Taylor and colleagues (Arthritis and Rheumatism, 38:229-234) found that 65% of women with FM reported sexual abuse compared to 52% of healthy controls. They also found that the abused group of FM patients reported more symptoms such as pain, weakness, weight changes, and depression that did the FM patients who had not been abused. Their conclusions were that sexual abuse was associated with more severe symptoms of FM but didn’t appear to be a causal factor.

Boisset-Pioro and colleagues (Arthritis and Rheumatism, 38:235-241) found that 37% of their FM sample had experienced childhood sexual abuse compared to 22% of their controls who were women with other rheumatic diseases. They concluded that there was an association between FM and the severity of sexual abuse (e.g. multiple abuse events).

Several things are important to note about both of these studies. First, they used clinical populations, that is, women who were seeking medical care for their FM. So we can expect that the women were distressed enough by their FM symptoms to seek care. Second, we know that people who have had many stressors in their lives or who have psychiatric disorders are more likely to seek treatment and that they are more likely to come from dysfunctional families where abuse is more likely to occur (especially families in which a parent has alcoholism). Third, neither study provides any proof of a causal relationship between sexual abuse and FM. This is a very important point because recently there have been attempts by some professionals to say that sexual abuse causes FM. There is no way that anyone could even begin to prove a causal link between abuse and FM without doing very long-term studies of children who were watched over many years to see who was abused and who developed FM as adults.

There is some very fascinating research underway in related fields that may begin to shed some more light on this apparent relationship. Recently some researchers in the area of gastrointestinal disorders (American Journal of Medicine, 97:108-118) found that patients with these disorders who had been abused were also more likely to have abnormal pain perception and environmental stressors. They also tended to blame themselves for their pain.

Another body of research that is emerging and was summarized in Scientific American (October, 1995) concerns brain changes in the hippocampus part of the brain in patients who had suffered severe abuse. The researchers hypothesize that changes in the hippocampus which deals with short-term and long-term memory may be due to the flooding of that part of the brain with cortisol which is released during stressful events.

Now perhaps I am making a large leap here, but it just might be possible that childhood sexual abuse as a stressor may make some vulnerable people more susceptible to brain changes in the pain perception parts of the brain. Evidence is beginning to accumulate in FM research that there are changes in pain perception in patients with FM and that there are brain changes in these patients also. Thus, it is possible that childhood sexual abuse could be one of the factors that causes FM through its effects on the hypothalamus-pituitary-adrenal axis which controls the output of cortisol and other hormones. Obviously, there is no evidence that abuse alone causes any disease or syndrome. However, it may be an significant factor for some patients.

Whether or not sexual abuse is causally related to FM, it is critical that patients with FM who have been abused recognize the possibility that abuse history may contribute to their overall distress, self-blame, feelings of powerlessness and lack of control. Lori Kondora, a nurse who interviewed adult women who had been sexually abused as children (Health Care for Women International, 16:21-30), found that while many women experienced low self-esteem, depression, addictive behaviors, anxiety, pain and eating disorders, some women also experienced resilience, independence, creativity, a deeper spirituality, and personal strength. Remembering was central to the beginning of the healing process and telling their stories to others enhanced that process.