Post-combat invincibility: Violent combat experiences are associated with increased risk-taking propensity following deployment
Introduction
Since March 2003, hundreds of thousands of US Soldiers have deployed to Iraq to engage in combat operations in support of Operation Iraqi Freedom (OIF). Many of these Soldiers have operated for extended periods under the highly stressful circumstances of urban combat, including a poorly delineated enemy force of guerrilla insurgents, the ever-present threat of roadside bombs and improvised explosive devices (IEDs), and recurrent exposure to violence and human suffering. Such traumatic combat experiences have been linked to elevated risk for mental health problems, particularly post-traumatic stress disorder (PTSD) and major depression (Helzer et al., 1987, Hoge et al., 2004, Jordan et al., 1991), but also high rates of somatic illness, substance abuse, and poor psychosocial adjustment (Beckham et al., 1998, IPGSG, 1997, Prigerson et al., 2002). Moreover, the frequency of mental health problems in military personnel returning from Iraq is significantly linked to the frequency and severity of combat exposure (Hoge et al., 2006, Kang and Hyams, 2005). As Soldiers return from the largest sustained combat operation in over three decades (Friedman, 2005), the military and civilian health-care systems will need to accommodate the enormous influx of combat veterans and effectively address their mental health needs.
In contrast to research on PTSD, there has been comparatively little attention directed toward other less clinically prominent behavioral outcomes of combat exposure that still have the potential to adversely impact the health and well-being of returning service members. A notably unaddressed public health concern is the potential for some combat veterans to show increased willingness to engage in high-risk behaviors upon return (Hooper et al., 2006). Because prolonged exposure to emotionally relevant stressors is often associated with behavioral adaptation and response habituation (Charney, 2004, Fischer et al., 2003, Ward et al., 1998) and produces structural, neurochemical, and functional changes in the emotional processing regions of the limbic system (Charney, 2004, Shin et al., 2006, Tischler et al., 2006), it is conceivable that Soldiers returning from intense combat may initially experience some difficulties readjusting to the requirements of non-wartime social functioning. Accounts of increased risk-taking behavior and feelings of “invincibility” have been reported among Soldiers returning from combat, but no published study has directly investigated this phenomenon from a medical or scientific perspective. This paper examines the relationship between specific combat experiences of Soldiers during their deployment to Iraq and their subsequent risk-taking propensity upon returning home. It was hypothesized that greater exposure to violent combat experiences would be associated with an increased habituation to dangerous situations and, therefore, greater propensity to engage in dangerous or high-risk activities upon returning home. Thus, Soldiers reporting greater exposure to combat experiences while deployed to Iraq were hypothesized to score higher on a measure of risk-taking propensity and actual risk-related behaviors than similarly deployed Soldiers reporting less exposure to such experiences.
Section snippets
Participants
Survey responses were collected from Soldiers at two time points. Initially, 2983 Soldiers completed a survey during the first three days after returning to the United States from a 12-month combat mission in Iraq in 2006. A follow-up survey was completed by 2244 (75.2%) of these same Soldiers 3 months later. Most of the drop in participation was due to Soldiers being geographically re-located to other units. Surveys from the two administrations were matched for those agreeing to provide their
Frequency of combat experiences
Table 1 presents the frequency of endorsement of the 37 combat experiences. The top five most frequently encountered experiences by deployed Soldiers included “Receiving incoming artillery rocket or mortar fire” (86.3%), “Knowing someone seriously injured or killed” (79.3%), “Encountered grateful civilians” (67.8%), “Working in areas that were mined or had IEDs” (66.3%), and “Having a member of your own unit become a casualty” (65.6%).
Principal components analysis
The responses to the 37 combat experiences were subjected to
Discussion
After a year-long deployment in Iraq, returning Soldiers reported numerous high intensity combat experiences, which were statistically reduced to seven general Combat Experience Factors (CEFs): Violent Combat Exposure, Human Trauma Exposure, Survived a Close Call, Buddy Killed/Injured, Killed an Enemy, Killed a Friendly/Non-Hostile, and Pride in the Mission. Several of these CEFs contributed unique variance to the prediction of risk-taking propensity. In particular, Soldiers with higher levels
Conflicts of interest
None of the authors declare any conflicts of interest that could affect the conduct of the study, the statistical analysis, interpretation, or reporting of the data.
Contributors
William D. S. Killgore was the primary individual involved in the conceptualization of the specific research question, analysis strategy, and choice of risk-taking measures, and also conducted the statistical analysis, conducted the literature review, and wrote the majority of the manuscript.
Dave I. Cotting contributed to the conceptualization of the research question and wrote the research protocol. He also contributed to revisions of the manuscript.
Jeffrey L. Thomas contributed to the
Role of funding source
Funding for this study was provided by the US Army Medical Research and Materiel Command (MRMC); the MRMC had no further role in study design; in the collection, analysis and interpretation of data; in writing of the report; and in the decision to submit the paper for publication.
Acknowledgements
The views expressed in this paper are those of the authors and do not reflect the official policy or position of the Department of the Army, the Department of Defense, the US Government, or any of the institutions with which the authors are affiliated. This information was reviewed by the Walter Reed Army Institute of Research and there is no objection to its presentation or publication.
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