Michael R. Bell

Risk factors associated with suicide in current and former US military personnel.

IMPORTANCE Beginning in 2005, the incidence of suicide deaths in the US military began to sharply increase. Unique stressors, such as combat deployments, have been assumed to underlie the increasing incidence. Previous military suicide studies, however, have relied on case series and cross-sectional investigations and have not linked data during service with postservice periods. OBJECTIVE To prospectively identify and quantify risk factors associated with suicide in current and former US military personnel including demographic, military, mental health, behavioral, and deployment characteristics. DESIGN, SETTING, AND PARTICIPANTS Prospective longitudinal study with accrual and assessment of participants in 2001, 2004, and 2007. Questionnaire data were linked with the National Death Index and the Department of Defense Medical Mortality Registry through December 31, 2008. Participants were current and former US military personnel from all service branches, including active and Reserve/National Guard, who were included in the Millennium Cohort Study (N = 151,560). MAIN OUTCOMES AND MEASURES Death by suicide captured by the National Death Index and the Department of Defense Medical Mortality Registry. RESULTS Through the end of 2008, findings were 83 suicides in 707,493 person-years of follow-up (11.73/100,000 person-years [95% CI, 9.21-14.26]). In Cox models adjusted for age and sex, factors significantly associated with increased risk of suicide included male sex, depression, manic-depressive disorder, heavy or binge drinking, and alcohol-related problems. None of the deployment-related factors (combat experience, cumulative days deployed, or number of deployments) were associated with increased suicide risk in any of the models. In multivariable Cox models, individuals with increased risk for suicide were men (hazard ratio [HR], 2.14; 95% CI, 1.17-3.92; P = .01; attributable risk [AR], 3.5 cases/10,000 persons), and those with depression (HR, 1.96; 95% CI, 1.05-3.64; P = .03; AR, 6.9/10,000 persons), manic-depressive disorder (HR, 4.35; 95% CI, 1.56-12.09; P = .005; AR, 35.6/10,000 persons), or alcohol-related problems (HR, 2.56; 95% CI, 1.56-4.18; P <.001; AR, 7.7/10,000 persons). A nested, matched case-control analysis using 20:1 control participants per case confirmed these findings. CONCLUSIONS AND RELEVANCE In this sample of current and former military personnel observed July 1, 2001-December 31, 2008, suicide risk was independently associated with male sex and mental disorders but not with military-specific variables. These findings may inform approaches to mitigating suicide risk in this population.

The association between deployment‐related posttraumatic growth among U.S. army soldiers and negative behavioral health conditions

OBJECTIVES This study assessed posttraumatic growth (PTG) in a sample of U.S. Army Soldiers using the Post-Traumatic Growth Inventory (PTGI), and the relationship between PTG and negative behavioral health (BH) conditions. DESIGN A sample of Soldiers with prior combat deployment experience (n = 1,834) completed an anonymous survey including demographics, the PTGI, and negative BH conditions. RESULTS Among previously deployed Soldiers, those reporting the highest number of combat experiences also reported significantly higher overall PTG. A significant inverse relationship was observed between PTG and recent suicidal ideation, whereby Soldiers reporting recent suicidal ideation reported significantly lower overall PTG. CONCLUSIONS This study quantified PTG resulting from deployment and demonstrated the degree to which combat experiences might result in PTG.

Interaction of Combat Exposure and Unit Cohesion in Predicting Suicide-Related Ideation Among Post-Deployment Soldiers

Suicide is one of the leading causes of death among U.S. Army soldiers. Suicide-related ideation, which is associated with suicide attempts and suicide, can cause considerable distress. In a sample of 1,663 recently redeployed soldiers, we used factor analysis and structural equation modeling to test the associations between combat exposure, unit cohesion, and their interaction in predicting suicide-related ideation. We found that combat exposure was a significant risk factor for suicide-related ideation, while unit cohesion was a significant protective factor. The significant interaction between the two factors indicated that soldiers who experienced greater combat exposure but also had higher levels of unit cohesion had relatively lower levels of suicide-related ideation. In addition, those who had higher levels of combat exposure and lower unit cohesion were most at risk for suicide-related ideation. Our findings indicate the importance of unit cohesion in protecting soldiers from suicide-related ideation and suggest a higher risk group of soldiers who should be targeted for interventions.

Factors Associated With Physical Aggression Among US Army Soldiers

There are a growing number of studies that have approximated levels of aggression and associated outcomes among combat veterans returning from Iraq and Afghanistan using brief screening assessments. However, further research to evaluate the relative role of combat exposures and overt physical behaviors is required to further elucidate potential associations between military service, combat deployment, and overt physical aggression. The purpose of the current study was to assess the prevalence of self-reported physical aggression in a sample of US Army soldiers using an adaptation of the Revised Conflict Tactics Scale (CTS2), and examine factors associated with higher levels of aggression. A population-based cross-sectional study was conducted at a single US Army Installation within a sample of active duty US Army soldiers (n = 6,128) from two large units. Anonymous surveys were collected 6 months following deployment to measure overt aggressive behaviors, posttraumatic stress disorder, anxiety, depression, traumatic brain injury, and misuse of alcohol. There were a relatively higher number of minor and severe physical overt aggressive actions reported among soldiers who previously deployed, notably highest among deployed soldiers reporting the highest levels of combat intensity. Soldiers screening positive for the misuse of alcohol were also significantly more likely to report relatively higher levels of physical aggression. This study quantified overt aggressive behaviors and associated factors, showing increasing combat exposures may result in increased physical aggression. Clinicians treating service members returning from combat may consider assessing relative levels of combat.

Combat Exposure, Unit Cohesion, and Demographic Characteristics of Soldiers Reporting Posttraumatic Growth

Posttraumatic growth (PTG) refers to the positive cognitive, spiritual, emotional, and social changes that can occur after a traumatic experience. The current study uses data from 1,663 soldiers who participated in a voluntary survey 6 months after redeployment. The purpose of this study was to predict posttraumatic growth from combat exposure, unit cohesion, and demographic characteristics. We found that greater combat exposure and stronger unit cohesion were associated with more PTG. Being married, a minority, and a junior enlisted soldier were also predictive of greater PTG. Our study defines a group of soldiers with low PTG who are at risk for adverse psychosocial problems. Our results suggest that unit cohesion could be targeted and strengthened to improve PTG.

The association between combat exposure and negative behavioral and psychiatric conditions

Abstract This study evaluated the association between cumulative combat exposures and negative behavioral and psychiatric conditions. A total of 6128 active-duty soldiers completed a survey approximately 6 months after their unit’s most recent combat deployment. The soldiers self-reported combat exposures and behavioral and psychiatric conditions. Multivariable logistic regression was used to assess the association between cumulative combat exposures and behavioral and psychiatric outcomes. In comparison with the referent group of soldiers not previously deployed, the soldiers categorized as having the highest cumulative combat exposures were significantly associated with self-reporting a history of behavioral and psychiatric diagnoses, problematic alcohol misuse, aggression, criminal behavior, and physical altercations with a significant other. The magnitude and the consistency of the association among the soldiers with the highest number of combat exposures suggest that the number of cumulative combat deployment exposures is an important consideration for identifying and treating high-risk soldiers and units returning from combat.

An epidemiologic investigation of homicides at Fort Carson, Colorado: summary of findings.

In response to an apparent clustering of homicides at Fort Carson, Colorado, the U.S. Army Public Health Command (formerly the U.S. Army Center for Health Promotion and Preventive Medicine) Behavioral and Social Health Outcomes Program conducted a multidisciplinary epidemiologic consultation to identify factors contributing to violent behavior among soldiers at Fort Carson. This article summarizes the findings of the epidemiologic consultation report as provided to the Secretary of the Army and the Fort Carson Senior Mission Commander and released in its entirety publicly July 2009 and elaborates on the mixed-methods analytic approach used to study a complex behavioral issue at the community level. To aid in answering the key study questions, six study arms were designed and carried out: (1) index case analysis, (2) confinee interviews, (3) analysis of installation-level trends, (4) retrospective cohort analysis, (5) soldier focus groups and interviews, and (6) aggression risk factors survey. Although not conclusive, the findings suggest a combination of individual, unit, and environmental factors converged to increase the risk of violent behaviors, which made clustering of negative outcomes more likely.

Combat Stressors Predicting Perceived Stress Among Previously Deployed Soldiers

While combat exposures are considered principle stressors in developing mental health problems, research suggests social support can reduce this risk. Using data from 1,592 previously deployed soldiers, we found five classes of soldiers based on their patterns of responses to items measuring perceived stress. In subsequent analyses, we found increased combat exposure predicted membership in classes with greater combat-related stress, while greater unit cohesion predicted membership in classes with lower perceived stress. Also, greater willingness to report misconduct predicted greater unit cohesion. Results suggest that unit cohesion plays a vital role in the reduction of perceived stress among soldiers.

The Association Between U.S. Army Enlistment Waivers and Subsequent Behavioral and Social Health Outcomes and Attrition From Service

Soldiers granted enlistment waivers for medical concerns, misconduct, or positive alcohol/drug tests may or may not be associated with an increased likelihood of negative behavioral outcomes. Soldiers in the population examined (n = 8,943) who were granted enlistment waivers from 2003 to 2008 were significantly more likely to subsequently be screened for alcohol/substance abuse, test positive for illicit substances, or receive an Army separation for behavioral misconduct. These associations were highest among Soldiers granted waivers for nonlawful alcohol/drug violations. Soldiers granted waivers for felony offenses and serious nontraffic violations were significantly less likely to separate from the Army compared with Soldiers not granted enlistment waivers.

Combat Exposure Factors Associated With the Likelihood of Behavioral and Psychiatric Issues

The objective was to evaluate correlated combat exposure factors among active-duty combat veterans deployed to Afghanistan and then determine how these factors are associated with behavioral and psychiatric issues postdeployment. Active-duty soldiers from one brigade combat team (N = 1,739) were surveyed to assess their most recent combat exposures and behavioral outcomes. Combat exposures were factor analyzed and included in a larger structural equation model. Three factors emerged from the analysis: some combat exposures (e.g., “active exposure”) are protective of screening positive for post-traumatic stress, while others (“passive exposure” and “exposure invoking emotion”) are predictive of screening positive for post-traumatic stress. These varying relationships should be considered during implementation of intervention and treatment of redeploying soldiers.