New Onset of Fibromyalgia After Exposure to a Combat Environment: A Longitudinal Cohort Study

Traumatic life events are hypothesized to be triggers for the onset of fibromyalgia. Posttraumatic stress disorder (PTSD) is a common comorbidity of fibromyalgia. However, limited prospective data are available on the development of fibromyalgia after exposure to high-magnitude stress.

This longitudinal cohort study of US military service members (N = 1,761) assessed fibromyalgia and PTSD before and upon return from combat deployment. Fibromyalgia was assessed with the 2011 questionnaire modification of the 2010 American College of Rheumatology preliminary diagnostic criteria for fibromyalgia. The PTSD Checklist Stressor-Specific Version was used to assess symptoms of PTSD.

The prevalence rates of fibromyalgia in service members at predeployment (men = 2.2%; women = 2.0%) were similar to rates in civilian populations. Following deployment, the prevalence of fibromyalgia increased significantly to 8.0% in men and 11.1% in women (P < 0.001). The prevalence of PTSD symptoms at predeployment was 20.7% in men and 18.3% in women. The prevalence post deployment increased slightly to 22.7% in men and 25.5% in women (P > 0.05). By odd ratios, service members with PTSD predeployment were 2.96 times more likely to develop fibromyalgia post deployment, and those with fibromyalgia predeployment were 3.12 times more likely to develop PTSD post deployment.

This study provides the largest prospective data to date to support exposure to the stress of deployment to a warzone as a significant factor related to the onset of fibromyalgia. The bidirectional comorbidity between fibromyalgia and PTSD suggests a potential link in the central nervous system and has implications for management.