According to a U. S. panel, many of the thousands of troops who suffer head injuries stand higher risk of depression, dementia and stress disorders, problems which often go undiagnosed. The report released today by the Academy's Institute of Medicine articulated that serious brain injuries account for 22 % of the U. S. casualties in the Iraq and Afghanistan wars which have resulted in 5,500 wounded from the military. This rate is almost double what was seen in the Vietnam War due to the increasing power of enemy attacks as well as stronger body armor and better medical care that keep more soldiers alive.

"It's a good news-bad news situation," said George W. Rutherford, a University of California, San Francisco, epidemiologist who led the panel. "I don't think we really knew how big a hole in scientific knowledge there is about blast-induced brain injuries. Because these kinds of blasts are survivable now where in the past they haven't been, it's a whole new spectrum of disease that the modern military has never really had to deal with before."

The report, paid for by the U. S. Veterans Affairs Department, reviewed 1,900 previous studies of brain trauma and found a link between moderate and severe injuries and rising depression, memory loss, aggression, Parkinson's-like tremors and social problems that hinder employment.

That "confirms what we in the community have long known -- that we're really still behind the curve on this," said Paul Rieckhoff, executive director of Iraq and Afghanistan Veterans of America, a New York-based group. "This research, the urgency, it should have been happening in 2004, not 2008," he added.

"If you have a gunshot wound to some specific part of your brain, I can tell you the consequences," Rutherford said. But with blast concussions, it's not even possible to say "if you have six of these, are you six times more likely to have something bad happen to you than if you've had one?"

Traumatic brain injury, or TBI, is a signature injury of the Iraq war with many of them with damage hidden inside the skull which is caused by an explosion's pressure wave. Though there is no outward injury, the severity can range from mild concussion to severe injury and as its not apparent many do not seek medical care for it. Returning soldiers have reported headaches, dizziness, memory loss, confusion, irritability, insomnia and depression and the military has said most of these recover with treatment. The report recommends that every soldier exposed to a blast, even a low-intensity one, be screened for TBI. They have also said that everyone should get a pre- and post-deployment brain-function test and the military has begun those steps.

The VA said it would consider the recommendations, and it has 60 days to decide if those long-term disorders will be presumed linked to brain-injured veterans' military service.