By Amanda Gardner
Between 9% and 14% of the soldiers were diagnosed with PTSD or depression resulting in serious impairment, while 23% to 31% were deemed to have some impairment. (The rates varied depending on the diagnostic criteria the researchers used.)
The pre-deployment rate of PTSD and depression among the soldiers was about 3% to 5%, roughly the same as that seen in the population at large, according to the study, which appears in the Archives of General Psychiatry.
Roughly half of the soldiers with PTSD or depression reported having abused alcohol or engaged in aggressive behavior, such as punching a wall or getting into a fight.
Next page: PTSD in vets an "immense" problem
PTSD is an "immense" problem in returning veterans, says Steven Huberman, PhD, dean of Touro College's School of Social Work, in New York City.
"Since the deployment to Iraq and Afghanistan started about seven years ago, we're seeing a significant difference from other military involvements, in the number and types of injuries, the types of deployments, the nature of the military force, and the impact on families and kids," says Huberman.
The study findings suggest that the standard time between deployments, 12 to 18 months, may not be sufficient for many soldiers to recover, and that soldiers with PTSD who are redeployed several times could pose a threat to themselves and to their units, the researchers say.
It's unclear why the rates of PTSD and depression among active duty and National Guard soldiers diverged a few months after they returned.
One explanation could be that soldiers in the National Guard tend to be more isolated when they get back to the U.S., says Jon Shaw, MD, a retired Army psychiatrist and a professor at the University of Miami's Miller School of Medicine.
"Reserve units lose group cohesion and solidarity to a greater degree than those in active units," Dr. Shaw says. "As long as they're involved in active units, they have some kind of group and interpersonal support system. Once they leave the military and go back to civilian life, it's a very tough adjustment."
Even when the care is free, medical facilities often aren't as easy for National Guard members to access as they are for active duty soldiers still living on military bases, Thomas and his colleagues note.
The study highlights the importance of providing appropriate treatment for returning veterans, Dr. Shaw says.