Twelve years after the United States launched Operation Enduring Freedom in Afghanistan, America’s longest war – a war fought halfway around the world, largely by all-volunteer ground forces subjected to multiple deployments which, in many cases, have added up to several years of service in theater – has taken its toll on the mental health of many service members.

The numbers compiled by the Armed Forces Health Surveillance Center tell the story: Nearly 1 million active-duty service members have been diagnosed with at least one mental disorder since 2000, and between 2003 and 2011, the number of them diagnosed with post-traumatic stress disorder (PTSD) increased by a factor of six. In the last dozen years, more than 130,000 PTSD cases have been recorded, and even after the drawdowns in Iraq and Afghanistan began in 2009, the rate of PTSD cases in the military has continued to increase every year.

In the last dozen years, more than 130,000 PTSD cases have been recorded, and even after the drawdowns in Iraq and Afghanistan began in 2009, the rate of PTSD cases in the military has continued to increase every year.

PTSD, a complex mental condition that can follow a life-threatening event such as military combat, accident, or personal assault, is marked by physical and psychological symptoms such as anxiety, depression, memory or cognition problems, and substance abuse. The disorder is associated with difficulties in social and family life. Because it shares symptoms with, or is often associated with, other mental health conditions or traumatic brain injury (TBI), it is almost certainly under-diagnosed among service members and veterans who have served in Iraq and Afghanistan. In its landmark 2008 study “The Invisible Wounds of War,” the nonprofit RAND Corporation estimated that about 19 percent of service members deployed to Iraq or Afghanistan have symptoms consistent with a diagnosis of PTSD or depression – and among those service members, only about half sought treatment.

When a service member comes home with a physical injury, it’s easy to see he or she is hurt, and the way to treat the injury may be straightforward. PTSD and other mental health conditions can be harder to recognize as such, and individuals may be reluctant or unwilling to seek clinical advice. While screening and diagnosis may identify individuals with PTSD symptoms, treatment may not be effective for everyone.

For many years – and especially over the last several years – the Department of Veterans Affairs (VA) has worked closely with the Department of Defense (DoD) to reduce both the number of service members who develop PTSD following trauma and to treat the number who continue to suffer chronic symptoms after diagnosis. The VA’s extensive apparatus for research and education on the prevention, understanding, and treatment of PTSD includes the National Center for PTSD, 10 Mental Illness Research, Education, and Clinic Centers (MIRECCs) located throughout the country, and its Office of Research and Development (ORD), whose investigators look at PTSD and other health problems from every angle – from basic science to issues of access to care in order to improve care for everyone.

VA’s PTSD research is focused on understanding the mechanisms and risk factors underlying PTSD, discovering “biomarkers” for early diagnosis and prevention, and the most effective ways to treat or provide care.

 

What’s Behind PTSD

Today little is known about how PTSD develops after traumatic exposure, either physiologically or psychologically, and this knowledge is necessary to enable clinicians to identify people at risk. VA researchers are concluding three large studies aimed at understanding the mental and physical health consequences of PTSD, and its relationship to other conditions, among veterans:

• The Veteran Health Study, which is recording physical and mental health data among about 10,000 members of the Vietnam Era Twin (VET) Registry, a cohort of more than 7,000 male twin pairs, both of whom served in the military during the Vietnam War. Formed 15 years ago to address questions about the long-term health effects of Vietnam service, the registry – one of the largest national twin registries in the United States – has become a valuable resource for genetic epidemiological studies of mental and physical health. “Previous analysis of the Twin Registry,” said Dr. Timothy O’Leary, acting chief research and development offficer at the VA, “has shown that approximately one-third to 40 percent of PTSD predisposition is genetically inherited. So if we’re able to understand, down to the gene level, the factors involved in inheritance, that helps us understand the mechanisms that may be employed in PTSD’s development – and if we understand those biochemical pathways in the brain, those become targets for therapeutic interventions. So this is the earliest phase of one approach to drug development.”

• Health ViEWS: The Health of Vietnam-Era Veteran Women’s Study, the most comprehensive examination of women Vietnam-era veterans to date, is examining the impact of wartime deployment on health and mental outcomes nearly 40 years later, as these women veterans approach their mid-60s.

• The National Vietnam Veterans Longitudinal Study has collected self-reported health information from Vietnam-era veterans who participated in the 1986-1987 National Vietnam Veterans Readjustment Study. The congressionally mandated study – the first reassessment since the original – could offer valuable insights about the long-term course of combat-related PTSD and related mental health disorders.

Each of these three studies is expected to report results in late 2013 or early 2014. “I think taken together they are a truly landmark set of studies,” O’Leary said. “They take complementary approaches aimed at answering the same questions – and even though they are not directly giving us new therapies, they will help us understand what we need to do in the future when therapies fail to achieve what we all want to achieve for PTSD, which is cure, rather than care.”

VA researchers, O’Leary said, are also conducting laboratory studies aimed at discovering the basic science behind the development of PTSD: physiological studies of the brain chemistry of both animal models and human subjects after stress, for example. Other investigators are enrolling service members and veterans from the current conflict in longitudinal studies aimed at identifying risk factors. One prominent example is the Marine Resilience Study, a joint VA/DoD study launched in 2008, which collects health data from Marines before deployment, at two points during deployment, and six months after returning from deployment.

Longitudinal studies of the current generation of veterans have been particularly challenging, said O’Leary: “People come back from Afghanistan and Iraq and sometimes in very short order are turned right around again,” he said. “We originally expected, when we started these studies, that maybe there would be a control group of people who weren’t deployed. That didn’t happen. Pretty much all the people who served in the military over the last 10-year period have found themselves in Southwest Asia at one time or another. So it’s a particularly difficult conflict to study.” Slightly more than half the participants in the Marine Resilience Study, for example, had already been deployed at least once before enrolling with researchers.