The Fort Hood soldier who killed three colleagues before killing himself was being evaluated for post-traumatic stress disorder, although he served four months on Iraq at a time combat for U.S. troops was over and he was not wounded.
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It's not clear whether the gunman, identified by law enforcement and military sources as Spc. Ivan Lopez, 34, actually had PTSD. Lt. Gen. Mark Milley said the shooter suffered from "mental issues," was on medication and was being evaluated for possible PTSD.
But experts said soldiers do not have to suffer a wound or trauma in combat to develop PTSD.
As part of a 10-year PTSD study funded by the Department of Defense, Dr. Joseph Calabrese said he’s learned that a significant number of soldiers who have combat-related PTSD also have civilian PTSD. He said soldiers can experience trauma as children, as adults before enlisting, and between deployments.
“People come home, and they can still experience trauma outside of the military,” said Calabrese, who directs the Mood Disorders Program at UH Case Medical Center in Cleveland. “You can still experience physical or sexual assault when you come home when you’re on leave. You’re not just experiencing trauma during combat.”
Civilian trauma can be physical or sexual assault, something that makes them feel helplessness or horror, he said.
Army Secretary John McHugh elaborated on the shooter's mental health issues today, telling a Senate committee that the shooter was "undergoing a variety of treatments and diagnoses of mental health issues ranging from depression to anxiety to sleep disturbance."
He was also taking Ambien, a prescription sleep aid, McHugh said. According to Ambien's warning label, it can cause "worsening of depression or suicidal thinking may occur."
Last month, a psychiatrist had evaluated Lopez, but the psychiatrist saw "no indication" that Lopez would become violent or suicidal, McHugh said. The psychiatrist planned to continue monitoring Lopez.
Calabrese said there’s a common misconception that PTSD is a stand alone diagnosis. He said it is often diagnosed with depression or an anxiety disorder. Symptoms of feeling hopeless or worthless, which are related to depression, can often lead soldiers to think about suicide, and substance abuse can drive them to act on those feelings.
“Every time you add another mental illness on top of anything -- certainly on top of PTSD -- the risk of harm to self goes up,” Calabrese said. He said that the risk of harm to others goes up as well.