Study Suggests Killing Experiences Independently Associated with Suicidal Ideation among Vietnam Veterans
The United States military has lost more troops to suicide than to combat for the second year in a row. The Army's suicide rate, 11.4 per 100,000 soldiers at the start of the Iraq War, had nearly doubled by 2009 to 21.8 per 100,000 soldiers, surpassing the suicide rate of the general population for the first time. While the DoD and VA have implemented several initiatives to decrease suicide, a better understanding of suicide associated risk factors remains of critical importance. This retrospective study tested the hypothesis that having killed in combat is associated with increased suicidal ideation and suicide attempts — independent of diagnoses of PTSD, depression, and substance use disorders. Investigators used data collected from Veterans who served in Vietnam and surrounding areas between 8/64 and 5/75, and who had participated in the National Vietnam Veterans Readjustment Study (NVVRS). Data that were analyzed was obtained from a subset of 259 participants selected to be representative of 1.3 million Vietnam Veterans, and included detailed information about combat experiences (e.g., having killed during combat), as well as clinical diagnostic data on PTSD, depression, and substance use disorders.
- Vietnam Veterans in this study with war-related killing experiences were twice as likely to report suicidal ideation as those who did not kill, even after accounting for PTSD, depression, substance use disorder diagnoses, and combat exposure. This is the first study demonstrating that killing experiences are independently associated with suicidal ideation, after taking mental health diagnoses into account.
- In regression analyses that included demographic variables, PTSD, depression, substance use disorders, combat experiences, and killing experiences, PTSD was the only variable significantly associated with suicide attempts. Nearly 14% of Veterans in this study met diagnostic criteria for current PTSD.
- The NVVRS is a cross-sectional study; as a result, causal relationships should not be assumed when interpreting these data. Moreover, the NVVRS was conducted many years after the Vietnam War, which may introduce significant recall biases.
- This investigation was conducted with male Vietnam Veterans only.
- It should not be assumed that suicidal ideation will always lead to suicidal fatality.
Dr. Maguen was supported by an HSR&D Career Development Award (RCD 06-042) and is part of HSR&D's Program to Improve Care for Veterans with Complex Comorbid Conditions, San Francisco, CA. Dr. Knight is Deputy Director of HSR&D.
Maguen S, Metzler T, Bosch J, Marmar C, Knight S, and Neylan T. Killing in Combat May Be Independently Associated with Suicidal Ideation. Depression and Anxiety 2012 Apr 13;e-pub ahead of print.