Grim toll: TBI ups risk of suicide in military personnel

Suicide is a major concern among military personnel, particularly since the start of combat in Afghanistan and Iraq. While depression plays a role, suicide risk is higher among deployed military personnel who’ve sustained more traumatic brain injuries (TBIs), even after controlling for clinical symptom severity, according to study published online May 15 in JAMA Psychiatry.

The interaction of depression severity and number of TBIs “suggests that the effects of depression on suicide risk are augmented by cumulative TBIs,” wrote authors Craig J. Bryan, PsyD, ABPP, of the National Center for Veterans Studies, Salt Lake City, and Tracy A. Clemans, PsyD, of the VA VISN 19 Mental Illness Research Education Clinical Center in Denver. “This is noteworthy because military personnel who have sustained multiple head injuries might be especially vulnerable to suicide risk when experiencing emotional distress.”

Suicide is currently the second leading cause of death among military personnel, and the rate has risen particularly sharply in the Army since the start of the Afghanistan and Iraq conflicts, explained Bryan and Clemans.

The study included 161 military personnel referred for evaluation and treatment of suspected head injury at a military TBI clinic in Iraq. All patients underwent a clinical interview and physical exam, as well as completing a standardized self-reporting measure of depression, posttraumatic stress disorder (PTSD), and suicidal thoughts and behaviors.

Results showed depression, PTSD and TBI symptom severity significantly increased with the number of TBIs. A single TBI increased incidence of lifetime suicidal thoughts or behaviors by 6.9 percent, while multiple TBIs resulted in a 21.7 percent increase of suicidal thoughts or behaviors. Suicidal ideation also increased with the number of TBIs.

Bryan and Clemans wrote that it’s possible TBI increases impulsivity and emotional distress, increasing suicide risk, or that cumulative TBIs and suicidal behavior are consequences of underlying impulsivity. “Regardless of the direction of causality, our current results suggest that assessing the number of TBIs experienced by a patient may help in determining the more enduring risk for suicidal behaviors over time.”

For more on TBI, read “Turning Up the Volume on a Silent Epidemic: Advanced Imaging & TBI” from the May/June issue of Health Imaging.