Post-deployment PTSD symptoms more common in military personnel with prior mental health disorders

"The relationship between preinjury psychiatric status and postinjury PTSD is not well understood because studies have used retrospective methods," write the authors. "The primary objective of our study was to prospectively assess the relationship of self-reported preinjury psychiatric status and injury severity with PTSD among those deployed in support of the conflicts in Iraq and Afghanistan." They study also sought to ascertain other demographic, military and deployment-related factors that exacerbate post-deployment PTSD.

Donald A. Sandweiss, M.D., M.P.H., from Naval Health Research Center, and colleagues, studied U.S. service members who participated in the Millennium Cohort Study, a program created in 2001 to examine the health status of military members before, during and after deployment. A total of 22,630 individuals completed a baseline questionnaire (which includes the PTSD Checklist-Civilian Version) before deploying and one or more follow-up questionnaires during or after their service. Information regarding deployment-related injuries was retrieved from the Joint Theater Trauma Registry (JTTR), a registry maintained by the U.S. Army Institute of Surgical Research, and the Navy-Marine Corps Combat Trauma Registry Expeditionary Medical Encounter Database (CTR EMED). The study cohort included participants from all branches of the U.S. armed forces, including the Reserves and the National Guard.

At baseline, 739 participants (3.3 percent) had at least one psychiatric disorder, defined as PTSD, depression, panic syndrome or another anxiety syndrome. Of the overall group, 183 individuals (0.8 percent) sustained a physical injury during deployment. Follow-up questionnaires showed that 1,840 participants (8.1 percent of the 22,630 subjects in the study population) had PTSD symptoms after deployment.

Participants who showed signs of PTSD at baseline had nearly five times the odds of developing the disorder after deployment. Similarly, among those who experienced other mental health issues were at baseline, the odds of post-deployment PTSD symptoms was 2.5 times more likely. Further, the study found each three-unit increase in Injury Severity Score (as assigned by the JTTR or CTR EMED) was associated with a 16.1 percent greater odds of having post-deployment PTSD symptoms. The authors note that baseline psychiatric status was a stronger predictor than injury severity.

The authors suggest that such screening might help to better protect service members during their time in the field. Checking pre-deployment mental health, they conclude, "might be useful to identify a combination of characteristics of deployed military personnel that could predict those most vulnerable or, conversely, those most resilient to post-deployment PTSD, thereby providing an opportunity for the development of pre-deployment interventions that may mitigate post-deployment mental health morbidity."