Symptoms of posttraumatic stress disorder (PTSD) are typical after deployment to a war zone, and may even represent a healthy reaction to stress, but can lead to problems with mental functioning if they persist, new research in Iraq vets suggests.

Past research has demonstrated that people exposed to life-threatening situations will show changes in their nervous and hormonal systems, Dr. Jennifer J. Vasterling of the VA Boston Healthcare System and her colleagues note, but it's not clear how long such symptoms last after exposure ends, and if they do last, what the consequences might be.

Vasterling and her colleagues are conducting a long-term study called the Neurocognition Deployment Health Study to help answer these questions.

In the current report, Vasterling and her team report the outcomes of neurological and psychological assessments of two groups of soldiers before and after deployment to Iraq.

Their study included 164 male and female Army soldiers assessed about a year after their return, and 104 tested an average of just 122 days after they had returned.

The researches found no relationship between the amount of time since a soldier had returned from deployment and his or her neuropsychological function.

There was no relationship between PTSD symptoms soon after deployment and the ability to pay attention, but the soldiers who still had PTSD symptoms a year after they returned from combat had a harder time focusing and paying attention.

The researchers also found that soldiers who had experienced more intense combat showed improved reaction time both soon after their return and a year later.

Attention problems can be very relevant to how a person functions in daily life, Vasterling noted in an interview, even though the deficits that she and her colleagues identified were relatively mild.

The hope, she said, is that these problems will resolve once a person's PTSD is treated. However, the researcher added, there are also strategies that can help people cope with their attention problems until they get better.

She and her colleagues are continuing to follow the soldiers, and one interesting question, she noted, is whether the increased reaction time they identified in those exposed to more intense combat might have a downside.

You have to wonder how taxing that gets, to be constantly prepared for a long, long period of time, Vasterling said.

SOURCE: Archives of General Psychiatry, September 2009.