There has been a threefold increase in new cases of self reported post-traumatic stress disorder symptoms among combat-exposed military personnel since 2001, according to a study published on bmj.com today.

Concerns have been raised about the health impact of military deployment. Studies have estimated as many as 30% of Vietnam War veterans developed post-traumatic stress disorder at some point following the war and, among 1991 Gulf War veterans, as many as 10% were reported to have post-traumatic stress disorder symptoms years after returning from deployment.

So researchers in San Diego analysed the effect of deployment on over 50,000 military personnel who were taking part in the Millennium Cohort Study (a large 22-year study of the health of US military personnel).

Baseline data were obtained between July 2001 and June 2003 (before the wars in Iraq and Afganistan) and participants were surveyed about their health three years later (June 2004 to February 2006).

Combat exposure was assessed and new onset post-traumatic stress disorder symptoms were measured using recognised criteria. Other information, such as cigarette smoking and problem alcohol drinking, was also recorded.

Over 40% of participants were deployed between 2001 and 2006; 24% deployed for the first time in support of the wars in Iraq and Afganistan between baseline and follow-up.

New onset post-traumatic stress disorder symptoms or diagnosis were reported by up to 87 per 1000 combat-deployed personnel and up to 21 per 1000 non-combat deployed personnel.

New onset symptoms were proportionately higher among participants who were female, divorced, enlisted, and in those who reported being a current smoker or problem drinker at baseline.

Persistent symptoms were found in 40-50% of participants who had post-traumatic stress disorder symptoms at baseline, suggesting that resolution of post-traumatic stress disorder may not be expected for several years.

These data show overall new incidence rates of 10 to 13 cases per 1000 person years and suggest a threefold increase in new onset self reported post-traumatic stress disorder symptoms or diagnosis among recently deployed military personnel with combat exposures, say the authors.

While the overall prevalence of post-traumatic stress disorder in the military is not high, a substantial number of new cases can be expected based on the number of service personnel deployed and exposed to combat in the wars in Iraq and Afganistan.

Identifying personnel with symptoms early may lead to a smaller burden of the disorder in the years to come if appropriate and timely treatments are provided. Meanwhile, future research should include efforts to better understand the resiliency and vulnerability to post-traumatic stress disorder symptoms among combat deployers, they conclude.

Source: British Medical Journal