A new picture of mental instability has emerged from three studies analyzing suicidal behavior in the U.S. Army, showing that although military suicide rates were only modestly higher than those of civilians, the overwhelming majority of those suicidal tendencies predated soldiers’ enlistment.

The military is often painted with the broad strokes of ruinous brain injuries and exploited youth, putting lost teenagers on the front lines and giving them clear, if highly risky, directions. The new trio of studies suggests this mental unwellness often arises far before soldiers ever enlist — that it’s the sick enlistee who is more at risk for suicide rather than the healthy enlistee who is turned sick by serving.

Far and away the most common risk factor for suicidal behavior was so-called “intermittent explosive disorder,” a term used by psychiatrists to describe the sudden flights of rage common among sufferers of posttraumatic stress disorder (PTSD). Roughly one in 10 soldiers received a diagnosis for intermittent explosive disorder, which is five times higher than the civilian rate and, in combination with a mental disorder rate twice that of civilian life, key for understanding why the suicide rate has risen in recent years.

“The people at highest risk of making an attempt struggled with depression and anxiety, or post-traumatic stress, in combination with impulsiveness and aggression,” Harvard psychologist and lead author of one of the studies, Dr. Matthew Nock, told The New York Times. “The former gets people thinking about suicide, and the latter gets them to act on those thoughts.”

The prevailing theory espoused by the studies’ researchers is actually that the present state of affairs bears close resemblance to the civilian suicide rate — 14 percent of soldiers thought about suicide, five percent planned it, and 2 percent attempted it — except that that in itself is also a problem. While physical injuries in the U.S. get treated without the bat of an eye, depression, anxiety disorders, and ADHD can remain undiagnosed for years all because of lacking physician oversight. So it’s not necessarily the Army that’s making soldiers become suicidal; rather, a portion of the already too-large pool of suicidal civilians enlists in the Army.

The first study tracked this behavior over the course of five years between 2004 and 2009. During that period, the suicide rate nearly doubled, reaching a high of over 23 people per 100,000. Since then, the rate has fallen more or less back down to the civilian rate of 20 per 100,000. Meanwhile, in-depth interviews designed to assess mental health found that 11 percent of soldiers warranted a diagnosis for intermittent explosive disorder. In the civilian population, that number is only two percent. As Matthew Nock suggests, it isn’t so much the aggression or the PTSD that’s driving soldiers to suicide; it’s the unique combination of the two.

In reality, controlling the aggressiveness or posttraumatic stress of post-enlisted soldiers isn’t the primary goal. “These studies provide knowledge on suicide risk and potentially protective factors in a military population,” National Institute of Mental Health (NIMH) Director Thomas Insel said in a news release,” but also ones “that can also help us better understand how to prevent suicide in the public at large.”

In the U.S. alone roughly 9.3 million people, or 4.0 percent of the population, lives with a serious mental illness, according to the Substance Abuse and Mental Health Services Administration. Serious mental illness is defined as one or more disorders that severely impair a person’s basic function and daily life. For any mental illness — meaning an episode of any duration, however brief — occurs in roughly 18.2 percent of the American adult public, or some 42.5 million people.

In the Army, these cases of mental illness turn into suicidal behavior in only a small cluster of people. If a concerted effort from all fronts — governmental, medical, and academic — can recognize the warning signs before the diseases are made manifest, they can ultimately reduce the chances that cases like intermittent explosive disorder turn into something deadly.

“A small minority of soldiers are responsible for a disproportionate amount of suicidal behavior,” wrote Dr. Matthew Friedman, of the National Center for PTSD, in an editorial to the three reports. “Better identification of and intervention with the cohort are likely to have the best payoff.”


Schoenbaum M, Kessler RC, Gilman SE, et al. Predictors of suicide and accident death in the Army Study to Assess Risk and Resilience in Servicemembers. JAMA Psychiatry. 2014.

Nock MK, Stein MB, Heeringa SG, et al. Prevalence and correlates of suicidal behavior among soldiers: Results from the Army Study to Assess Risk and Resilience in Servicemembers. JAMA Psychiatry. 2014.

Kessler RC, Heeringa SG, Stein MB, et al. Thirty-day prevalence of DSM-IV mental disorders among non-deployed soldiers in the U.S. Army: results from the Army Study to Assess Risk and Resilience in Servicemembers. JAMA Psychiatry. 2014.