(January 31, 2008 - Insidermedicine) Experiencing a concussion during active duty is associated with an increased risk for post-traumatic stress disorder (PTSD) among soldiers returning from service in Iraq, according to research published in the New England Journal of Medicine.

Here are some facts about injuries in modern soldiers:

•    Improved protective equipment means that soldiers are more likely to survive injuries, including head and neck injuries.

•    Head and neck injuries have been labeled a signature injury of the Iraq and Afghanistan wars. The proportion of troops who experience mild traumatic brain injuries is estimated to be as high as 18%.

•    Many troops have reported persistent postconcussive symptoms, such as irritability, memory problems, headache, and difficulty concentrating.

Researchers from the Walter Reed Army Institute of Research surveyed over 2,500 United States army infantry soldiers three to four months after returning from active duty in Iraq. The survey included validated measures of physical health, depression, and PTSD. The investigators compared outcomes among injured soldiers who experienced mild traumatic brain injury, defined as an injury with loss of consciousness or altered mental status, with those who experienced other injuries or no injury.

Among those who experienced loss of consciousness, 44% met criteria for PTSD, compared with 27% of those experiencing altered mental status, 16% with other injuries, and 9% with no injuries. Those who experienced mild traumatic brain injury, particularly if it was associated with loss of consciousness, reported poorer physical health, with more missed work days, medical visits, and somatic and postconcussive symptoms. After adjusting for the presence of PTSD and depression, however, these soldiers only differed from the others with respect to a higher incidence of headaches.

Today's research highlights the link between experiencing a concussion during active duty and the risk for developing PTSD. The presence of PTSD and depression appears to place soldiers at increased risk for overall poorer physical health.

For Insidermedicine in Depth, I'm Dr. Susan Sharma.