WEDNESDAY, Sept. 9, 2009 (HealthDay News) -- U.S. soldiers returning from Iraq with post-traumatic stress disorder (PTSD) appear to show growing attention deficits in the year following their return, Boston University researchers report.
In addition, intense combat experiences were associated with faster, survival-linked reaction times. Earlier research has found that as soldiers encounter stressful and life-threatening situations, there are changes in their brains that direct their thinking, learning and memory toward survival, the researchers noted.
"It's important to realize that the problems with attention that we saw were relatively mild," stressed lead researcher Jennifer J. Vasterling, chief of psychology at the VA Boston Healthcare System and a professor of psychiatry at Boston University School of Medicine. "But what they suggest is that we should be thinking about the broader picture of how people function when they return from war."
Treating psychological symptoms is a critical first step, Vasterling said. "But, we need to also be asking them about how other areas of their lives are affected, and try to help them with these concerns as well," she added.
The report is published in the September issue of the Archives of General Psychiatry.
For the study, Vasterling's team evaluated 268 men and women - all regular active-duty soldiers who served in Iraq between 2003 and 2006. Before and after going to Iraq, all the participants were given psychological tests that measured their response time, attention and memory.
Some of the soldiers were assessed immediately on their return and then again a year later. Others were assessed within 122 days after coming back from Iraq.
"We found that soldiers with post-traumatic stress symptoms performed more poorly on an attention task than soldiers without post-traumatic stress symptoms," Vasterling said. "But this was only true for soldiers who had been back for a year. Soldiers experiencing psychological stress reactions who had only recently returned from Iraq did not show the same problems."
The researchers also found that soldiers who had been exposed to more combat while in Iraq had quicker reaction times than those who saw less combat.
"We think a lot about the emotional impact of war, but what this study demonstrates is that as stress responses go on longer, their impact widens," Vasterling said. "When the stress reactions were new, they did not yet affect cognitive functioning."
However, as soldiers endured the stress of having been to war and any disruption it might have caused, chronic stress started causing other problems in addition to emotional distress, Vasterling said. "We see that with health and other sorts of quality of life indices among people who have suffered post-traumatic stress disorder for long periods of time," she said.
In this case, cognitive functioning might also be a window into the biology of the brain, Vasterling noted.
"We know that the brain responds in certain ways to stress, but then usually returns to its normal state. However, if these neurobiological changes go on for too long, they can overtax the system." she said.
Therefore, long term changes in attention and other cognitive processes might indicate that the brain's biology is becoming increasingly reactive, which can eventually take a toll on health, Vasterling said.
"Even the beneficial change of quicker reaction times might mean that the soldier is in a perennial 'action-ready' mode, which is great in the war zone, but can get taxing if it goes on too long," she said.
Cognitive processes such as attention are also important for everyday life, Vasterling said. "Being able to sustain concentration helps you function at work and at school and it helps you enjoy things like movies, books and conversation," she said.
Simon A. Rego, an assistant professor of psychiatry and behavioral sciences at Albert Einstein College of Medicine and associate director of psychology training at Montefiore Medical Center in New York City, said the study is "yet another in a growing literature that warns about the potential negative consequences of PTSD on the long-term health of soldiers returning from Iraq."
Given that these findings were in soldiers who had been back from Iraq for a year, the results also have implications for the natural progression of PTSD symptoms, and "suggest that relatively acute PTSD symptoms may exert less of an effect on attention than more chronic PTSD symptoms," Rego said.
While these PTSD-related impairments may be considered mild compared with those found in other neurological disorders, it is important to note that they still represent changes in the soldier's functioning that could be experienced as distressing, and while the relationship between PTSD and attention impairment was minimal early on, it strengthened over time, Rego said.
"It appears we may be witnessing another example of the consequences of war on the human nervous system," Rego said. "It draws on and sharpens the body's natural response and adaptation to times of intense stress, which may be adaptive in the short-term, but is ultimately maladaptive in the long-term once soldiers are removed from combat."
For more information on PTSD, visit the U.S. National Institute of Mental Health.