For military personnel, having at least one psychiatric disorder before deployment to Iraq or Afghanistan appears to increase the likelihood of developing posttraumatic stress disorder (PTSD) after deployment, the prospective Millennium Cohort Study showed.
The presence of a psychiatric disorder pre-deployment was associated with a 2.52-fold (95% CI 2.01 to 3.16) greater likelihood of post-deployment PTSD, independent of injury severity and numerous other potential confounders, according to Cynthia LeardMann, MPH, of the Naval Health Research Center in San Diego, and colleagues.
The findings, which were reported in the May issue of Archives of General Psychiatry, "suggest that the Millennium Cohort or similar questionnaires completed before deployment 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," the authors wrote.
Although previous studies have examined the association between pre-injury psychiatric status and post-injury PTSD, this is the first prospective study to do so, according to the researchers.
They used the Millennium Cohort Study, in which participants completed questionnaires at baseline and periodically thereafter. The current analysis included 22,630 military personnel who were deployed to Iraq or Afghanistan before completing at least one follow-up questionnaire.