Stress May Be Selective About Pain It Causes

Can psychological stress trigger or reawaken pain in persons who have garden-variety types of pain—say, pain limited to particular muscles, bones, or joints? Probably.

Can psychological stress also trigger or reactivate fibromyalgia-type pain, a pain that can cause every muscle in the body to shout out in distress and that has been long suspected of being of psychological origin? Probably not.

These answers come from a study conducted by Karen Raphael, Ph.D., an associate professor of psychiatry at the New Jersey Medical School in Newark, and her coworkers. Their results were published in the November issue of Pain.

The study is also interesting because it used the terrorist attacks on the World Trade Center in New York City as a natural experiment to test the effects of psychological stress on physical pain. It all started back in fall 2000 when Rollin Gallagher, M.D., a professor of psychiatry and a director of pain medicine at the MCP/Hahnemann School of Medicine in Philadelphia, and her colleagues launched a population-based study to explore putative links between pain and depression in women in the New York City/New Jersey metropolitan area—or what Gallagher calls “the first really well-designed community study of fibromyalgia and mood.” By fall 2001, they had interviewed some 12,000 women for the study.

Then came the terrorist attacks on September 11, 2001. Raphael and her coworkers realized that they had an excellent database on the pain experiences of women in the New York City/New Jersey area prior to the attacks and that they might be able to use it to conduct a prospective study to find out whether the psychological stress of the attacks had increased pain among those women.

Early in 2002—some six months after the terrorist attacks—Raphael and her team randomly contacted 1,300 women from the earlier study. The researchers asked them whether they were currently experiencing pain and, if so, what kinds. The researchers also asked questions to learn how much they had been impacted by the terrorist attacks—for instance, whether they had been in the vicinity of the World Trade Center at the time of the attacks or lost a family member or close friend to the attacks.

Raphael and her colleagues then attempted to see whether there was an increase in the reporting of certain types of pain by the 1,300 women after the terrorist attacks compared with before. Whereas 37 percent had reported pain in the muscles, bones, or joints in 2000, 40 percent did so in 2002—a statistically significant difference. Regarding the reporting of fibromyalgia-like pain, however, there was only a 1 percent increase from 2000 to 2002—from 11 percent to 12 percent, not a statistically significant difference.

Thus, psychological stress may be able to trigger or reawaken pain in muscles, bones, or joints but not fibromyalgia pain, Raphael and her coworkers concluded.

What’s more, the scientists could not find any link between the degree to which subjects were impacted psychologically by the terrorist attacks and their susceptibility to postattack fibromyalgia pain. This finding, they believe, also suggests that psychological stress does not trigger or reactivate fibromyalgia pain.

Gallagher told Psychiatric News that the most important message from this study is that “fibromyalgia does not increase, does not occur more often, in the context of a major disaster like the terrorist attacks. The disaster does cause psychological stress, but does not cause fibromyalgia per se.”

The study was funded by a National Institutes of Health grant.

An abstract of the study, “A Community-Based Survey of Fibromyalgia-like Pain Complaints Following the World Trade Center Terrorist Attacks,” can be accessed on the Web at www.sciencedirect.com/science/journals by clicking on “Pain” and then the November issue. ▪