Pre-exposure factors may also contribute to polytrauma. About half of troops in Iraq and Afghanistan are volunteers, often fresh out of high school. Some have had a difficult upbringing that may render them less resilient to injury. The National Guard reservists are generally far older and often not optimally physically fit, he continued.
Louis M. French, Psy.D., said that he and his coinvestigators have found that among military personnel with mild TBI and bodily injuries, those with more severe bodily injuries reported less TBI-related neurobehavioral symptoms such as headache, forgetfulness, anxiety, and depression than did those with relatively minor bodily injuries.
It’s a paradoxical finding. One possible explanation is that people who are very seriously injured are happy to be alive and simply ignore minor neurobehavioral symptoms. Also, it’s easier for people who are more seriously injured to see tangible improvement resulting from their rehabilitation program, as when they start to walk again or get a prosthetic device, said Dr. French, director of the traumatic brain injury service at Walter Reed Army Medical Center in Washington.
In a recent study, Dr. French and coworkers found that 55% of service members with mild TBI reported symptoms consistent with the diagnosis of post-concussive disorder 12 months later.
"These are very different trajectories than you’d expect to see in a civilian population," he observed.
Dr. Michael Pollanen of Toronto, who is chief forensic pathologist for Ontario, said that his emerging hypothesis is that blast-related TBI might be a variant of diffuse axonal injury that leads to a distinctive syndrome of neuropsychiatric impairment. He has seen such injuries at the cellular level under the microscope at autopsy; now the search is on for a means of identifying diffuse axonal injury in blast survivors.
Four Items Screen for Mild TBI
• Question 1: Were you exposed to a trauma or blast while in Operation Enduring Freedom/Operation Iraqi Freedom?
• Question 2: As a result of the trauma or blast did you have a loss or alteration in consciousness (see stars, have bell rung, feel disoriented or confused)?
• Question 3: Did you develop problems with headache, insomnia, dizziness, thinking, or behavior immediately to soon after the trauma or blast?
• Question 4: Do you still have the problems with headache, insomnia, dizziness, thinking difficulties or behavior that you developed immediately to soon after the trauma or blast?
None of the speakers reported any financial conflicts.