A soldier who already had a mental health disorder has a higher risk of developing posttraumatic stress disorder (PTSD) after deployment, compared to peers with no such medical histories, researchers from the Naval Health Research Center reported in Archives of General Psychiatry today.

The authors wrote:

“The relationship between pre-injury psychiatric status and post-injury PTSD is not well understood because studies have used retrospective methods. 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.”

The researchers also tried to find out whether other factors might impact on post-deployment PTSD rates.

Donald A. Sandweiss, M.D., M.P.H., and team gathered data on 22,630 military personnel who had completed a baseline questionnaire. They had all taken part in the Millennium Cohort study, created in 2001 to find out what the health status of soldiers were before deployment and afterwards.

The checklist asked questions about their mental health before deployment, as well as before and after their military service.

The researchers also gathered data regarding deployment-related injuries from the JTTR (Joint Theater Trauma Registry), which included individuals from all US military armed forces branches, as well as National Guard Reserves.

3.3% (739) of the participants had at least one mental disorder, which included depression, panic syndrome, PTSD, or another anxiety syndrome. 183 people (0.8%) from the overall group were injured physically during deployment. According to follow-up questionnaires, 8.1% (1,840) of 22,630 participants had PTSD symptoms after deployment.

Those who already had signs of PTSD at baseline were five times as likely to develop a disorder post-deployment, compared to other people, the authors wrote. Individuals who had had other mental health issues before deployment had a 2.5 times greater chance of developing PTSD.

Every three-unit injury in the (physical) Injury Severity Score) was linked to a 16.1% greater chance of developing PTSD symptoms after deployment.

The researchers also noticed that an individual’s baseline psychiatric status was a strong predictor of injury severity.

If service members are screened more thoroughly, perhaps they may be better protected while in the field, the authors suggest.

The authors concluded:

(Checking pre-deployment mental health..) “..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.”

“Preinjury Psychiatric Status, Injury Severity, and Postdeployment Posttraumatic Stress Disorder”
Donald A. Sandweiss, MD, MPH; Donald J. Slymen, PhD; Cynthia A. LeardMann, MPH; Besa Smith, PhD, MPH; Martin R. White, MPH; Edward J. Boyko, MD, MPH; Tomoko I. Hooper, MD, MPH; Gary D. Gackstetter, DVM, PhD, MPH; Paul J. Amoroso, MD, MPH; Tyler C. Smith, MS, PhD; for the Millennium Cohort Study Team
Arch Gen Psychiatry. 2011;68(5):496-504. doi:10.1001/archgenpsychiatry.2011.44

Written by Christian Nordqvist