In this study, researchers assessed the tenderness, sensitivity to pain, and distribution of fibromyalgia syndrome (FS)-related symptoms (such as pain sensitivity, sleep disturbances, headaches, etc.) in 29 post-traumatic stress disorder (PTSD) patients as compared to a control group of 37 healthy subjects. The goal was to determine the prevalence of FS in patients with PTSD, and to compare the differences between PTSD patients with and without FS.

Predictably, the PTSD patients reported higher levels of tenderness, a lower quality of life, and a higher rate of physical impairment. PTSD subjects also reported a significantly higher percentage of FS-related symptoms than their matched controls.

The researchers found that 20% of the PTSD subjects met the diagnostic criteria for FS. Patients with both conditions did not differ from those with only PTSD in terms of the core PTSD symptoms (i.e. intrusion and avoidance), but patients with both conditions had significantly higher scores on the SCL-90R. Those areas with particularly high scores were paranoia, phobia, anxiety, and depression.

The authors explore the relationship between the two conditions:

"The prevalence of 20% fibromyalgia syndrome found here is far greater than in the general population (2%)...The finding that there is a correlation between pain and PTSD is in accordance with earlier studies. Kuch et al. found that, among 60 patients treated for fibromyalgia syndrome in a pain clinic, the prevalence of phobias and PTSD were 3.2 times more common in victims of minor road vehicle accidents than in subjects with non-vehicular-related onset of pain...The present study indicates that fibromyalgia syndrome has a substantial overlap with PTSD, which supports the psychological background of the disorder."

"The results of our study raise the question of whether fibromyalgia syndrome is, in fact, a stress-related disease. Goldenberg states that fibromyalgia syndrome is not a psychiatric disease, however, he emphasizes the relationship to psychological stress."

Amir M, Kaplan Z, Neumann L, Sharabani R, Shani N, and Buskila D. Posttraumatic stress disorder, tenderness, and fibromyalgia. Journal of Psychosomatic Research 1997;42(6):607-613.