Suicide in the military: Capability and means

by Michael D. Anestis, Ph.D.

Suicide is one of the most poorly understood phenomena involved in mental health.  Indeed, even within the select field of suicidology, a number of myths contradicted by robust empirical evidence persist as commonly held beliefs (Joiner, 2010).  As I've mentioned many times, both on this site and in peer reviewed articles, I tend to view suicidal behavior through the lens of the Interpersonal-Psychological Theory of Suicidal Behavior (IPTS; Joiner, 2005) and a pivotal reason for that is the theory's focus on mechanisms - variables that make suicidal plausible (or unlikely).  When we understand mechanisms, we develop a clearer understanding of why a symptom or behavior emerges and, perhaps most importantly, how to address it in treatment.

This fall, Dr. Craig Bryan and I decided to look at potential mechanisms that might explain an interesting discrepancy within the suicide literature: the number of non-lethal to lethal suicide attempts.  Depending on where you look, you'll find reports of up to 25 non-lethal attempts for every lethal attempt.  Put more simply, the vast majority of individuals who make suicide attempts survive.  The IPTS explains this discrepancy by noting that the vast majority of those with suicidal desire have not acquired the capability for suicide and are thus unable to make lethal attempts on their first try (or, in many cases, to make an attempt at all) due to the fear and pain involved in the behavior.  Over time, however, individuals develop the capacity through repeated exposure to pain and provocation, which allows them to overcome those sensations in future attempts.  In this sense, many individuals essentially practice up to the capability for lethal suicidal behavior.

What interested Dr. Bryan and I was the potential that, in the military, this situation might operate somewhat differently.

As many of you likely already know, suicide is a growing concern in the military.  Over the past three years - for the first time in recorded history - the suicide rate in the military has exceeded that of the general population (Department of Defense Task Force on the Prevention of Suicide by Members of the Armed Forces, 2010).  A number of theories exist that might explain part of this issue.  From the IPTS perspective, a sizable portion of this situation can be explained by elevated capability in military populations.  In 2009, Dr. Bryan, Chad Morrow, Thomas Joiner and I reported that, in a sample of US Air Force personnel who had recently completed basic training, soldiers exhibited higher levels of the acquired capability than did civilians in both clinical and non-clinical populations.  More impressively, however, they also exhibited higher average levels of the acquired capability than civilians with a history of multiple suicide attempts.  Given this information, it appears that when soldiers desire suicide, they are highly capable of engaging in serious or lethal suicidal behavior and, as such, over the past several years, something must have happened that increased suicide desire within this population.

Dr. Bryan and I considered all of this and couldn't help but wonder, given the higher capability for suicide amongst military perosnnel, whether the ratio of non-lethal to lethal suicide attempts might be lower in military personnel than in the general population.  Using public data available through the Department of Defense and the Centers for Disease Control and Prevention (both from 2010), we decided to compare the number of non-lethal and lethal attempts across these populations to determine whether a greater proportion soldiers who attempt suicide die relative to the general population.  We anticipated this would be the case for two reasons: a greater familiarity with and comfort around firearms and an elevated capability for suicide. 

Before reporting the numbers, I should note one significant issue: these data only included non-lethal suicide attempts that resulted in emergency medical attention.  As a result, these numbers without question will drastically underestimate the total number of individuals - both soldiers and civilians - who made non-lethal attempts.

So....what did we find?

In total, there were 1,144 reported suicide attempts within the military and 503,359 in the general population in 2010

Non-lethal versus lethal attempts in military versus general population

Of the 1,144 attempts in the military, 863 were non-lethal and 281 were lethal (3.07 non-lethal attempts for every death).

Of the 503,359 attempts in the general population, 464,995 were non-lethal and 38,364 were lethal (12.12 non-lethal attempts for every death).

This difference - 3.07 versus 12.12 - was statistically significant, meaning that a much higher proportion of suicide attempts in the miltary resulted in death than in the general population.

Does this hold true across sex and age?

There are substantially more men than women in the military, so we wanted to make sure this difference wasn't simply due to the fact that the military was largely male.

Male soldiers made 934 suicide attempts (653 non-lethal, 281 lethal; 2.32:1 ratio).  Males in the general population made 229,481 attempts (199,204 non-lethal, 30,277 lethal; 6.58:1 ratio).  This difference was statistically significant (and the 2.32:1 ratio is particularly troubling).

Female soldiers made 224 suicide attempts (210 non-lethal; 14 lethal; 15:1 ratio).  Females in the general population made 273,814 attempts (265,727 non-lethal; 8,087 lethal; 32.86:1 ratio).  This difference was also statistically significant.

Looking at these numbers, regardless of whether we looked at males or females, soldiers who made suicide attempts were substantially more likely to die than were members of the general population.

We also considered differences across age groups (less than 25 years old, 25-29, 30-39, and 40+).  In each case, the non-lethal to lethal ratio in the military was significantly lower than in the general population (see our paper in the Journal of Affective Disorders for detailed numbers on that). 

Do more soldiers use self-inflicted gunshot wounds as their attempt method?

Given their extensive training in and familiarity with firearms, Dr.Bryan and I wondered whether access to lethal means might explain part of these difference.  Put another way, we wondered wither a higher proportion of military attempts - non-lethal and lethal - would involve self-inflicted gunshot wounds.

Within the military, 40 (4.6%) of non-lethal attempts involved self-inflicted gunshot wounds (17 with privately owned firearms, 23 with military issued firearms).  Within the general population, 4,643 (1.0%) non-lethal attempts involved self-inflicted gunshot wounds.  This difference was statistically significant.

Within the military, 175 (62.28%) lethal suicide attempts involved self-inflicted gunshot wounds (136 with privately owned firearms, 39 with military issued firearms).  Within the general population, 19,392 deaths by suicide (50.5%) involved self-inflicted gunshot wounds.  This difference was also statistically significant.

Looking at these numbers, we can say without hesitation that a greater proportion of suicidal behavior in the military - lethal or non-lethal - involves the use of an extemely highly lethal means.  Given this, training in and familiarity with firearms certainly appears to play a role in military suicide and the lower ratio of non-lethal to lethal attempts in soldiers.

What about when we consider behavior that doesn't involve firearms?

If access to firearms explained everything, we would expect the ratio of non-lethal to lethal attempts to be equivalent across the military and general population.

In the military, 929 attempts (823 non-lethal, 106 lethal; 7.76:1 ratio) did not involve firearms.  In the general population, 479,324 attempts (460,352 non-lethal, 18,972 lethal; 24,27:1 ratio) did not involve firearms.  This difference was statistically significant.

What these numbers tell us is that, even when we look only at suicidal behavior not involving firearms, the ratio of non-lethal to lethal attempts in the military is lower than in the general population.  This speaks to the increased capability for suicide in military samples.  Even if they choose a method other than firearms, they're more likely to die than are individuals in the general population.

Does this mean that the military makes less lethal means more lethal?

One possibility is that soldiers tend to choose more lethal means (firearms or other highly lethal means).  Another possibility is that soldiers render less lethal means more lethal.  To test this, we looked at a common low lethality method: intentional overdose. 

In the military, 542 attempts (529 non-lethal; 13 lethal; 40.69:1 ratio) involved intentional overdose.  In the general population, 272,775 attempts (266,176 non-lethal, 6,599 lethal; 40.34:1 ratio) involved intentional overdose.  This difference was *not* significantly different.

These numbers tell us that, when soldiers use low lethality means, the means do not become more lethal.  A soldier is no more likely to die from an intentional overdose than is a member of the general population.  This points very clearly to the notion that soldiers are more likely from an attempt due to their choice of method.

Conclusions

Looking over all of this, a consistent message appears.  When soldiers attempt suicide, they are substantially more likely to die than are members of the general population who make attempts.  This is due in part to training in and familiarity with firearms, but is also due to an elevated capability for suicide, which enables them to opt for more lethal methods in general.  None of this is to say that suicidal desire in the general population isn't dangerous or that intentional overdose never results in death.  It simply points out that some methods are more lethal than others and suicidal desire is more likely to translate into death by suicide in military personnel than in the general population.

If you or anyone you know is experiencing thougths of suicide, please call 1-800-273-TALK.  This number includes help specifically for military personnel.

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Dr. Mike Anestis is an assistant professor in the Department of Psychology at the University of Southern Mississippi and the director of the Suicide and Emotion Dysregulation lab.