MONDAY, Feb. 14 (HealthDay News) -- Among those who served in U.S. military operations in Afghanistan and Iraq and who were evacuated due to a psychiatric condition, nonmilitary members were more likely than military personnel to return to duty, new research shows.

Nonmilitary personnel -- including diplomats, private contractors and Department of Defense civilians -- account for about 50 percent of U.S. personnel serving in Iraq and about two-thirds of those in Afghanistan.

"Nonmilitary personnel play an increasingly critical role in modern wars," Dr. Steven P. Cohen, of Johns Hopkins School of Medicine in Baltimore, and colleagues wrote in their report published Feb. 14 in CMAJ: Canadian Medical Association Journal.

Their study looked at 2,155 nonmilitary members who were evacuated from Iraq and Afghanistan between 2004 and 2007. Injuries were categorized as either non-war-related (such as non-cardiac chest pain or circulatory disorders) or war-related (such as combat-related, traumatic brain injury or psychiatric).

The researchers found that 75 percent of medically evacuated nonmilitary personnel did not return to duty and were less likely to return to duty after war-related injuries. But nonmilitary personnel were more likely than military personnel to return to duty after being evacuated for health problems not related to war or after being evacuated with a psychiatric illness.

"The observation that military personnel were more likely to be evacuated with war-related injuries, and nonmilitary members with non-war-related injuries, was not unexpected," Cohen and colleagues wrote.

"What was surprising was that the principal contributor to this disparity was the higher evacuation rates among military personnel than among nonmilitary personnel because of psychiatric diagnoses (9.1 percent versus 2.1 percent). This effect was amplified by the fact that military personnel were less likely than nonmilitary members to return to duty after evacuation because of a psychiatric condition."

Because "nonmilitary members are expected to play an increasingly prominent role in future military operations, recognizing the types of medical conditions they experience may be useful in implementing preventive measures and treatment strategies," the researchers concluded.

More information

The U.S. Deployment Health Clinical Center addresses a wide range of deployment-related health conditions and concerns.