Even as a soldier diagnosed with mental illness opened fire at Fort Hood, Texas, this week, a river of troubled veterans from the Iraq and Afghanistan wars keeps flowing out of the military, according to data from the Department of Veterans Affairs.
The Pentagon's struggle to cope with war's invisible wounds is certain to intensify after the revelation that the gunman, Spc. Ivan Lopez, was suffering depression and anxiety and was being examined for signs of post-traumatic stress disorder after serving in Iraq in 2011.
Lopez killed three soldiers Wednesday and injured 16 other people before taking his own life in a parking lot at the post.
About 1,000 veterans of the Iraq and Afghanistan war era are diagnosed each week with post-traumatic stress disorder and more than 800 with depression, according to VA statistics.
The Pentagon said Thursday that more than 155,000 U.S. troops have PTSD and that more than three-quarters of them are combat veterans.
The disorder is characterized by symptoms such as flashbacks, nightmares, emotional numbness or hyper-vigilance that follow a traumatic experience. The symptoms persist, becoming more severe rather than going away and lasting longer than a month, said Paula Schnurr, acting executive director at the VA's National Center for PTSD.
This week's mass shooting at Fort Hood, six months after a former Navy man killed 12 people at the Washington Navy Yard, underscores the vast mental health problems confronting the U.S. military as the last of two protracted, simultaneous wars winds down.
In addition to widespread PTSD and other mental illnesses, record suicide rates reported by the military appear to be spilling into veterans' lives as civilians, said Janet Kemp, the VA's chief suicide prevention officer.
Suicide rates among veterans ages 18-24 who are enrolled in VA health programs killed themselves at a rate of 80 per 100,000 in 2011, the latest year for which data are available. Non-veterans of the same age had a rate of 20 per 100,000 for 2009 and 2010, the latest available data from the Centers for Disease Control and Prevention.
"This group of young veterans appears to be in some trouble," Kemp said.
Lt. Gen Mark Milley, Fort Hood's commanding officer, said that protocols for treating and identifying troubled soldiers would be reviewed in the aftermath of Wednesday's shootings.
After more than a decade of war, the military has poured resources into identifying and treating behavioral health problems as never before. The number of available therapists increased 43% between the end of 2009 and December 2013 to 9,425 military, civilian and contractor mental health care providers, the Pentagon said.
But the extent of these illnesses and the complicated nature of multiple problems — including mild traumatic brain injuries from exposure to roadside bombs — appear to have left military doctors perennially behind the curve, according to independent reviews.
Scientists assembled by the Institute of Medicine (IOM), the health arm of the National Academy of Sciences, completed four major investigations in the past year that found shortcomings in the Pentagon's efforts to cope with behavioral health, traumatic brain injury and substance abuse among troops.
Unlike previous wars, the conflicts in Iraq and Afghanistan were fought by a military of modest proportions that required multiple combat deployments for troops in order to fight two long wars at the same time, the scientists note.
By 2011, more than 960,000 current and former servicemembers had been diagnosed with at least one psychological disorder. About half were suffering more than one.
Nine months after the 2009 killing of 13 soldiers at Fort Hood by an Army psychiatrist, mental resources at the base were crammed with patients, "full to the brim," said Steve Braverman the base hospital commander at the time. About every fourth soldier on the post, or about 10,000 people, were receiving counseling for marital strife, combat stress and other issues.
An IOM assessment issued a year ago found that despite more intensive efforts to provide behavioral health resources to servicemembers and their families, "the response does not match the magnitude of the problems, and many readjustment needs are unmet or unknown."
A study by the IOM published in late 2012 urged the Pentagon to acknowledge a "public health crisis" in the growing abuse of alcohol and prescription medications. An assessment by another panel of IOM scientists in February suggested that after years of treating combat troops for mild traumatic brain injuries related to exposure to bomb blasts, the military knows little about the long-term damage caused by this wound.
Lopez had reported that he was diagnosed with a mild TBI after a deployment to Iraq in 2011, Milley said.
The latest study by an IOM panel issued several weeks ago noted that the Army and other service branches have produced programs aimed at preventing mental health problems but said there's little evidence any of them work.
Schnurr cautioned that while "anger and irritability are symptoms of PTSD ... the vast majority of people with PTSD never engage in aggression."
She said research has shown an 80% long-term success rate of PTSD symptoms fading away among veterans treated at the VA after a series of weekly therapies using validated treatment procedures.
Melissa Earle, an associate dean at the Touro College Graduate School of Social Work in New York City, said traumatic brain injury is more closely tied to a lack of impulse control than PTSD.
Further complicating the lives of veterans, particularly those without lingering behavioral issues or who are managing their problems with appropriate care, is the lens through which society sees them after incidents such as Wednesday's Fort Hood attack and the one there in 2009.
Alex Horton, a former GI who served in Iraq and later worked for the VA as a communications specialist, worries that a negative stigma about Iraq and Afghanistan will only grow and persist after this week's events.
"There's going to be veterans applying for jobs out there," Horton said. "The last thing hiring managers are going to see when they go to bed is that this killer (Lopez) was an Iraq War veteran."
Horton, who writes about veterans issues, says he is convinced that one reason the jobless rate for this generation remains persistently high — currently at about 10% — is that some employers are afraid to hire them.
He said he fears that many employers believe "that you could be set off by anything. ... I think that is the cultural assumption that is really damaging us."
Contributing: Liz Szabo