The Combat Experience Log: a web-based system for the in theater assessment of war zone stress

Hippocampal volume and volume asymmetry prospectively predict PTSD symptom emergence among Iraq-deployed soldiers

BACKGROUND

Evidence suggests a link between smaller hippocampal volume (HV) and post-traumatic stress disorder (PTSD). However, there has been little prospective research testing this question directly and it remains unclear whether smaller HV confers risk or is a consequence of traumatization and PTSD.

METHODS

U.S. soldiers (N = 107) completed a battery of clinical assessments, including structural magnetic resonance imaging pre-deployment. Once deployed they completed monthly assessments of traumatic-stressors and symptoms. We hypothesized that smaller HV would potentiate the effects of traumatic stressors on PTSD symptoms in theater. Analyses evaluated whether total HV, lateral (right v. left) HV, or HV asymmetry (right - left) moderated the effects of stressor-exposure during deployment on PTSD symptoms.

RESULTS

Findings revealed no interaction between total HV and average monthly traumatic-stressors on PTSD symptoms b = -0.028, p = 0.681 [95% confidence interval (CI) -0.167 to 0.100]. However, in the context of greater exposure to average monthly traumatic stressors, greater right HV was associated with fewer PTSD symptoms b = -0.467, p = 0.023 (95% CI -0.786 to -0.013), whereas greater left HV was unexpectedly associated with greater PTSD symptoms b = 0.435, p = 0.024 (95% CI 0.028-0.715).

CONCLUSIONS

Our findings highlight the importance of considering the complex role of HV, in particular HV asymmetry, in predicting the emergence of PTSD symptoms in response to war-zone trauma.

Assessing the impact of the Royal Canadian Mounted Police (RCMP) protocol and Emotional Resilience Skills Training (ERST) among diverse public safety personnel

BACKGROUND

Public safety personnel (PSP; e.g., border services personnel, correctional workers, firefighters, paramedics, police, public safety communicators) are frequently exposed to potentially psychologically traumatic events. Such events contribute to substantial and growing challenges from posttraumatic stress injuries (PTSIs), including but not limited to posttraumatic stress disorder.

METHODS

The current protocol paper describes the PSP PTSI Study (i.e., design, measures, materials, hypotheses, planned analyses, expected implications, and limitations), which was originally designed to evaluate an evidence-informed, proactive system of mental health assessment and training among Royal Canadian Mounted Police for delivery among diverse PSP (i.e., firefighters, municipal police, paramedics, public safety communicators). Specifically, the PSP PTSI Study will: (1) adapt, implement, and assess the impact of a system for ongoing (i.e., annual, monthly, daily) evidence-based assessments; (2) evaluate associations between demographic variables and PTSI; (3) longitudinally assess individual differences associated with PTSI; and, (4) assess the impact of providing diverse PSP with a tailored version of the Emotional Resilience Skills Training originally developed for the Royal Canadian Mounted Police in mitigating PTSIs based on the Unified Protocol for the Transdiagnostic Treatment of Emotional Disorders. Participants are assessed pre- and post-training, and then at a follow-up 1-year after training. The assessments include clinical interviews, self-report surveys including brief daily and monthly assessments, and daily biometric data. The current protocol paper also describes participant recruitment and developments to date.

DISCUSSION

The PSP PTSI Study is an opportunity to implement, test, and improve a set of evidence-based tools and training as part of an evidence-informed solution to protect PSP mental health. The current protocol paper provides details to inform and support translation of the PSP PTSI Study results as well as informing and supporting replication efforts by other researchers.

TRIAL REGISTRATION

Hypotheses Registration: aspredicted.org, #90136. Registered 7 March 2022-Prospectively registered.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT05530642. Registered 1 September 2022-Retrospectively registered. The subsequent PSP PTSI Study results are expected to benefit the mental health of all participants and, ultimately, all PSP.

Demographic and Occupational Risk Factors Associated With Suicide-Related Aeromedical Evacuation Among Deployed U.S. Military Service Members

INTRODUCTION

Suicide is a significant problem in the U.S. military, with rates surpassing the U.S. general population as of 2008. Although there have been significant advances regarding suicide risk factors among U.S. military service members and veterans, there is little research about risk factors associated with suicide that could be potentially identified in theater. One salient study group consists of service members who receive a psychiatric aeromedical evacuation out of theater. The primary aims of this study were as follows: (1) determine the incidence of suicide-related aeromedical evacuation in deployed service members, (2) identify demographic and military characteristics associated with suicide-related aeromedical evacuation, and (3) evaluate the relationship between suicide-related aeromedical evacuation from a deployed setting and military separation.

MATERIALS AND METHODS

This was an archival analysis of U.S. Transportation Command Regulating and Command and Control Evacuation System and Defense Manpower Data Center electronic records of U.S. military service members (N = 7023) who were deployed to Iraq or Afghanistan and received a psychiatric aeromedical evacuation out of theater between 2001 and 2013. χ2 tests of independence and standardized residuals were used to identify cells with observed frequencies and proportions, respectively, that significantly differed from what would be expected by chance. In addition, odds ratios were calculated to provide context about the nature of any significant relationships.

RESULTS

For every 1000 psychiatric aeromedical evacuations that occurred between 2001 and 2013, 34.4 were suicide related. Gender, ethnicity, branch of service, occupation classification, and deployment theater were associated with suicide-related aeromedical evacuation (odds ratios ranged from 1.37 to 3.02). Overall, 53% of all service members who received an aeromedical evacuation for any psychiatric condition had been separated from the military for a variety of reasons (both voluntary and involuntary) upon record review in 2015. Suicide-related aeromedical evacuation was associated with a 37% increased risk of military separation compared to evacuation for another psychiatric condition (P < 0.02).

CONCLUSIONS

Findings provide novel information on risk factors associated with suicide-related aeromedical evacuation as well as military separation following a suicide-related aeromedical evacuation. In many cases, the psychiatric aeromedical evacuation of a service member for suicidal ideations and their subsequent separation from active duty is in the best interest of the individual and the military. However, the evacuation and eventual military separation can be costly for the military and the service member. Consequently, the military should focus on indicated prevention interventions for individuals who show sufficient early signs of crisis and functional problems so that specialized interventions can be used in theater to prevent evacuation. Indicated prevention interventions should start with leaders' awareness and mitigation of risk and, when feasible, evidence-based interventions for suicide risk provided by behavioral health (eg, brief cognitive behavioral therapy for suicide). Future research should evaluate the feasibility, safety, and efficacy of delivering suicide-related interventions in theater.

Factors Associated With Suicide Ideation in US Army Soldiers During Deployment in Afghanistan

IMPORTANCE

Understanding suicide ideation (SI) during combat deployment can inform prevention and treatment during and after deployment.

OBJECTIVE

To examine associations of sociodemographic characteristics, lifetime and past-year stressors, and mental disorders with 30-day SI among a representative sample of US Army soldiers deployed in Afghanistan.

DESIGN, SETTING, AND PARTICIPANTS

In this survey study, soldiers deployed to Afghanistan completed self-administered questionnaires in July 2012. The sample was weighted to represent all 87 032 soldiers serving in Afghanistan. Prevalence of lifetime, past-year, and 30-day SI and mental disorders was determined. Logistic regression analyses examined risk factors associated with SI. Data analyses for this study were conducted between August 2018 and August 2019.

MAIN OUTCOMES AND MEASURES

Suicide ideation, lifetime and 12-month stressors, and mental disorders were assessed with questionnaires. Administrative records identified sociodemographic characteristics and suicide attempts.

RESULTS

A total of 3957 soldiers (3473 [weighted 87.5%] male; 2135 [weighted 52.6%] aged ≤29 years) completed self-administered questionnaires during their deployment in Afghanistan. Lifetime, past-year, and 30-day SI prevalence estimates were 11.7%, 3.0%, and 1.9%, respectively. Among soldiers with SI, 44.2% had major depressive disorder (MDD) and 19.3% had posttraumatic stress disorder in the past 30-day period. A series of analyses of the 23 grouped variables potentially associated with SI resulted in a final model of sex; race/ethnicity; lifetime noncombat trauma; past 12-month relationship problems, legal problems, and death or illness of a friend or family member; and MDD. In this final multivariable model, white race/ethnicity (odds ratio [OR], 3.1 [95% CI, 1.8-5.1]), lifetime noncombat trauma (OR, 2.1 [95% CI, 1.1-4.0]), and MDD (past 30 days: OR, 31.8 [95% CI, 15.0-67.7]; before past 30 days: OR, 4.9 [95% CI, 2.5-9.6]) were associated with SI. Among the 85 soldiers with past 30-day SI, from survey administration through 12 months after returning from deployment, 6% (5 participants) had a documented suicide attempt vs 0.14% (6 participants) of the 3872 soldiers without SI.

CONCLUSIONS AND RELEVANCE

This study suggests that major depressive disorder and noncombat trauma are important factors in identifying SI risk during combat deployment.

Cortisol, Testosterone, and Prospective Risk for War-zone Stress-Evoked Depression

Introduction

The major challenges of efforts to reveal biological risk factors and biomarkers of depression include the complexity of underlying systems, interactions with other systems, and contextual factors governing their expression. Altered endocrine function is believed to be a central contributor to depressive illness, but across studies, evidence for a link between endocrine markers and depression has been mixed, inconclusive, or conditional in nature. In the present study, we evaluated basal testosterone (T), cortisol (C), and CO2 inhalation-stress-reactivity measures of these hormones (TR, CR) as pre-deployment moderators of the later impact of war-zone stressors on depression symptoms in-theater.

Materials and Methods

At pre-deployment, U.S. soldiers (N = 120) completed demographic, clinical and hormone measures, and during deployment, they completed monthly, web-based assessments of war-zone stressors and depression symptoms (N = 533 observations). Mixed effects models estimated the effects of the pre-deployment hormone profiles in moderating war-zone stressors' impact on in-theater depression. Models also tested whether hormonally linked risk for later stress-evoked depression depends on pre-existing depression.

Results

Controlling for pre-deployment depression, high T was protective; whereas TR had depressogenic effects that were amplified by pre-deployment depression. Further, high C was protective, but heightened CR was depressogenic, but only among those with elevated pre-deployment depression.

Conclusions

Findings highlight the importance of examining basal and reactivity measures of endocrine function, and use of prospective, longitudinal models to test hypothesized causal pathways associated with depression vulnerability in the war-zone. Results also suggest that pre-existing depression and cortisol may work in tandem to increase vulnerability for later stress-evoked depression in the war-zone.

Dual-hormone stress reactivity predicts downstream war-zone stress-evoked PTSD

BACKGROUND

The crucial role of the hypothalamic-pituitary-adrenal axis (HPA) in stress-related homeostasis suggests dysregulated HPA involvement in the pathogenesis of post-traumatic stress disorder (PTSD), yet most studies examining linkages between HPA axis measures and PTSD have yielded null findings. One untested explanation for this inconsistency is a failure to account for simultaneous adrenal and gonadal influence. Here we tested the singular and interactive effects of cortisol (C_R) and testosterone (T_R) reactivity as moderators of war-zone stress evoked PTSD emergence in the war-zone.

METHODS

U.S. soldiers (N=120) scheduled for deployment to Iraq completed pre-deployment measures of C_R and T_R stress reactivity to a CO₂ inhalation challenge. Once deployed, monthly assessments of exposure to traumatic war-zone stressors and PTSD symptoms were collected via a web-based assessment system.

RESULTS

Cortisol hypo-reactivity potentiated the pathogenic impact of war-zone stressors only in soldiers for whom the CO₂ challenge did not elevate testosterone, suggesting that the dual hormone stress reactivity profile of blunted cortisol and testosterone may confer increased risk for PTSD emergence by potentiating the pathogenic effects of war-zone stressors.

CONCLUSIONS

Findings underscore the utility of assessing both HPA and HPG stress reactivity when assessing PTSD vulnerability and may help inform efforts for enhanced soldier screening and inoculation to war-zone stressors.

How Do Aftermath of Battle Experiences Affect Returning OEF/OIF Veterans?

Aftermath of battle experiences (ABE) may contribute to adverse mental and physical health outcomes. This study examined ABE and their effect on health functioning and posttraumatic stress disorder (PTSD) in 66 OEF/OIF/OND Veterans. Bivariate correlations were conducted to investigate the contribution of ABE to PTSD and health functioning, after controlling for combat experiences. Additionally, a mediation analyses was conducted on Role Limitations due to Emotional Problems. Results suggested that the association between ABE and Role Limitations due to Emotional Problems was mediated by PTSD. These initials findings suggest the need for more research on differences in deployment experiences.

Internet screening for anxiety disorders: Treatment-seeking outcomes in a three-month follow-up study

Although many people use the internet to diagnose mental health problems, little is known about the relationship between internet self-diagnosis and treatment-seeking. The MACSCREEN (a validated, self-report screening tool for anxiety and depression) was posted on our clinic homepage and respondents were invited to take an anxiety test. Three months after completing the MACSREEN and a variety of symptom severity scales, respondents were emailed a follow up questionnaire asking about treatment-seeking behaviours. Of the 770 MACSCREEN respondents, 103 completed the follow-up questionnaire. Of these, 100% met criteria for at least one anxiety or mood disorder diagnosis and 51% sought treatment after completing the MACSCREEN. In the 49% who did not seek treatment, fear of medication (57%), discomfort talking to their doctor about anxiety (28%) and the belief that symptoms were not severe enough (28%) were cited as barriers. Compared to non-seekers, treatment-seekers were significantly more likely to meet screening criteria for Generalized Anxiety Disorder, Obsessive Compulsive Disorder, Posttraumatic Stress Disorder and Depression. Higher Sheehan Disability Scale scores and being married (versus single) significantly increased the odds of treatment-seeking, suggesting that functional impairment and disease burden on the family may be stronger predictors of treatment seeking than overall severity of symptoms.

5-HTTLPR genotype potentiates the effects of war zone stressors on the emergence of PTSD, depressive and anxiety symptoms in soldiers deployed to iraq

Exposure to war zone stressors is common, yet only a minority of soldiers experience clinically meaningful disturbance in psychological function. Identification of biomarkers that predict vulnerability to war zone stressors is critical for developing more effective treatment and prevention strategies not only in soldiers but also in civilians who are exposed to trauma. We investigated the role of the serotonin transporter linked polymorphic region (5-HTTLPR) genotype in predicting the emergence of post-traumatic stress disorder (PTSD), depressive and anxiety symptoms as a function of war zone stressors. A prospective cohort of 133 U.S. Army soldiers with no prior history of deployment to a war zone, who were scheduled to deploy to Iraq, was recruited. Multilevel regression models were used to investigate associations between 5-HTTLPR genotype, level of war zone stressors, and reported symptoms of PTSD, depression and anxiety while deployed to Iraq. Level of war zone stressors was associated with symptoms of PTSD, depression and anxiety. Consistent with its effects on stress responsiveness, 5-HTTLPR genotype moderated the relationship between level of war zone stressors and symptoms of emotional disturbance. Specifically, soldiers carrying one or two low functioning alleles (S or LG ) reported heightened symptoms of PTSD, depression and anxiety in response to increased levels of exposure to war zone stressors, relative to soldiers homozygous for the high functioning allele (LA ). These data suggest that 5-HTTLPR genotype moderates individual sensitivity to war zone stressors and the expression of emotional disturbance including PTSD symptoms. Replication of this association along with identification of other genetic moderators of risk can inform the development of biomarkers that can predict relative resilience vs. vulnerability to stress.

Acute stress disorder versus chronic posttraumatic stress disorder: inhibition of fear as a function of time since trauma

BACKGROUND

Previous work has shown that inhibition of fear is impaired in posttraumatic stress disorder (PTSD) resulting from both civilian and combat trauma. The purpose of the present study was to investigate the inhibition of learned fear in traumatized individuals diagnosed with either acute stress disorder (ASD) or PTSD. This is the first study to use a conditioned inhibition paradigm with traumatized individuals within a month of trauma exposure. We hypothesized that impaired fear inhibition would be evident in PTSD, but not ASD.

METHOD

Using established translational, psychophysiological methods including fear-potentiated startle, and skin conductance, we examined fear acquisition, stimulus discrimination, and the transfer of learned safety in a Croatian population with ASD or PTSD. This cross-sectional study included three age-matched groups: healthy nontrauma controls (n = 27), a group with chronic PTSD (10 or more years since trauma exposure, n = 24), and a group with ASD (30 days or less since trauma exposure, n = 27).

RESULTS

The presence of trauma-related psychopathology, whether acute or chronic, was associated with an impaired ability to transfer learned safety based on fear-potentiated startle measures, while healthy control subjects showed significant fear inhibition in the presence of the safety cue compared to the danger cue, F(1,26) = 12.64, P = .001.

CONCLUSIONS

These data expand our previously observed findings of PTSD-associated fear inhibition deficits by demonstrating that trauma-related impairments in safety learning are evident within 30 days of trauma exposure.

Combat experiences, pre-deployment training, and outcome of exposure therapy for post-traumatic stress disorder in Operation Enduring Freedom/Operation Iraqi Freedom veterans

The association between exposure to multiple potentially traumatic events (PTEs) and subsequent increased risk of post-traumatic stress disorder (PTSD) is well established. However, less is known about the relation between exposure to numerous PTEs, as is typical with military service, and treatment outcome. Furthermore, there has been little research examining military specific protective factors, such as pre-deployment preparedness, on PTSD treatment response. The current study investigated combat exposure and potential moderators of treatment outcome for exposure therapy in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) veterans with PTSD. One hundred and eleven OEF/OIF veterans diagnosed with PTSD participated in 8 weeks of exposure therapy. Results indicated that increased combat exposure was associated with a reduced rate of change in PTSD symptoms but not depression symptoms. These findings were consistent across two measures of combat exposure. There was preliminary support for the moderating effect of pre-deployment preparedness on the association between combat exposure and treatment response. Together, these findings suggest that increased combat exposure is associated with poor treatment response in veterans with PTSD; however, this can be reduced by elevated pre-deployment preparedness.

An examination of the relation between combat experiences and combat-related posttraumatic stress disorder in a sample of Connecticut OEF-OIF Veterans

BACKGROUND

Combat exposure is an important risk factor for posttraumatic stress disorder (PTSD). However, little research has examined specific combat experiences associated with PTSD and confirmatory factor analytically (CFA)-derived re-experiencing, avoidance, dysphoria, and hyperarousal symptom clusters.

METHODS

A total of 285 predominantly older National Guard/Reservist OEF-OIF Veterans completed an anonymous mail survey that assessed demographics and deployment history, a broad range of combat experiences, PTSD, and unit and postdeployment social support.

RESULTS

Personally witnessing someone from one's unit or an ally unit being seriously wounded or killed (β = 0.22), and being exposed to "friendly" fire (β = 0.14) and land mines/traps (β = 0.13) were the only three combat experiences associated with severity of combat-related PTSD symptoms, after adjustment for age, relationship status, unit support, postdeployment social support, and other combat experiences. Differential patterns of associations were observed for specific combat experiences in relation to CFA-derived symptom clusters (e.g., experiencing "friendly" fire was associated with re-experiencing and dysphoria symptoms, but not avoidance and hyperarousal symptoms). Personally witnessing someone from one's unit or an ally unit being seriously wounded or killed (odds ratio [OR] = 4.34; 95% confidence interval [CI] = 1.62-11.61) and being exposed to "friendly" fire (OR = 2.94; 95%CI = 1.16-7.47) emerged as independent predictors of a positive screen for probable PTSD.

CONCLUSIONS

Results of this study suggest that witnessing someone in one's unit or ally unit being seriously wounded or killed while in a combat zone and being exposed to "friendly" fire are most strongly associated with combat-related PTSD in this sample of OEF/OIF Veterans. Examination of the relation between specific combat experiences and combat-related PTSD in OEF/OIF Veterans may help inform etiologic models of PTSD, and guide prevention and treatment approaches in this population.