The Hypervigilance of Battle Haunts Returning Iraq War Vets

NEW ORLEANS, Aug. 1 -- Combat soldiers returning from Iraq don't get over it quickly, according to a VA study reported here. Their neuropsychological adaptations to warfare are not easily set aside.

Although their reaction times were better, soldiers returning from Iraq performed mildly worse on tasks requiring sustained attention, verbal learning, and visual-spatial memory compared with soldiers who were not sent overseas, said Jennifer J. Vasterling, Ph.D., of the Southeast Louisiana Veterans Health Care System here.

The soldiers were also significantly more tense and confused than they had been before deployment, Dr. Vasterling and colleagues reported in the Aug. 2 issue of the Journal of the American Medical Association.

It is not clear how long these effects will last, but they have the potential to negatively affect soldiers' long-term health and impair their ability to perform the day-to-day tasks of civilian life, the investigators said.

The findings were not explained by depression or post-traumatic stress disorder, they added. Nor was there evidence of exposure to environmental toxins, which was suggested as a causative factor linked to neuropsychological problems in some Gulf War veterans.

Instead, the neurological changes identified in the current study likely reflect the hypervigilance required in combat situations. The soldiers had learned to react quickly to potentially life-threatening situations but had "dampened" their attention, learning, and memory when it came to non-threatening events, the researchers said.

The study differs from previous assessments of combat veterans in that it obtained baseline measurements before the soldiers were deployed and did not rely entirely on subjective self-reports after the soldiers returned, the investigators said.

The researchers administered a battery of neuropsychological tests to 654 active-duty soldiers in 2003, before they were deployed to Iraq, and again in 2005 about two months after they returned. The study also included a comparison group of 307 active-duty soldiers not deployed overseas.

Nearly all the soldiers sent to Iraq reported combat experiences, including receiving hostile incoming small-arms fire (98%), participating in combat patrols or missions (91%), and seeing fellow soldiers seriously wounded or killed (55%). Nearly half (49%) participated in combat missions daily, and 14% were wounded or injured in combat.

Compared with their baseline measurements and with soldiers who had not been sent to Iraq, the returning soldiers performed significantly worse as a group on tasks of sustained attention (P

An important question not answered by the study is what the long-term health effects for Iraq war veterans might be, according to editorialists Matthew Hotopf, Ph.D., of the Institute of Psychiatry in London, and Simon Wessely, F.Med.Sci., of the King's Center for Military Health Research, also in London.

"Although data on the distribution of test performances are not presented, the implication is that the effect represents a minor change for the population as a whole rather than significant impairments in a few," the editorialists said.

"The final question for concerned veterans is whether the changes will persist," they concluded. "Given the lack of prior literature on neuropsychological functioning in populations of returning veterans, the planned follow-up of this cohort, with further rigorous neuropsychological testing and clinical monitoring, will be most welcome and certainly most important."

The study was supported in part by grants from the U.S. Army Medical Research and Material Command and the Veterans Affairs Clinical Science Research and Development program.