Relationship between traumatic brain injury history and recent suicidal ideation in Iraq/Afghanistan-era veterans

Influence of affective instability on suicidal ideation beyond traumatic brain injury and posttraumatic stress disorder in veterans

OBJECTIVE

Mild traumatic brain injury (TBI) is associated with long-term consequences, including greater risk for posttraumatic stress disorder (PTSD) and suicidal ideation. Affective instability is also independently related to PTSD and suicidality, which may explain why some individuals continue to experience chronic psychiatric complaints following mild TBI. The purpose of the present study was to evaluate affective instability as a key factor for PTSD and suicidal ideation among Veterans with and without TBI.

METHOD

Participants (N = 299 Veterans; 86.96% male) completed the Personality Assessment Inventory (PAI) and structured clinical interviews for TBI and psychiatric diagnoses. Hierarchical linear regression was used to evaluate main and interaction effects.

RESULTS

There were no significant differences in affective instability (p = 0.140) or suicidal ideation (p = 0.453) between Veterans with or without TBI. Individuals with TBI were more likely to have a PTSD diagnosis (p = 0.001). Analyses evaluating PTSD diagnosis as an outcome indicated a main effect of affective instability (p < 0.001), but not TBI (p = 0.619). Analyses evaluating suicidal ideation as an outcome demonstrated an interaction effect between PTSD and affective instability beyond the effects of TBI (p = 0.034).

CONCLUSIONS

Severe Affective instability appears to be a key factor in suicidal ideation among Veterans beyond TBI or PTSD history. PTSD was more strongly associated with suicidality at lower and moderate levels of affective instability. At severe levels of affective instability, however, Veterans with and without PTSD experienced suicidal ideation at similar rates. Findings suggests that high levels of affective instability not better explained by other psychiatric conditions confers similar suicidality risk to that of PTSD in a Veteran population.

A Practical Review of Suicide Among Veterans: Preventive and Proactive Measures for Health Care Institutions and Providers

Suicide rates among veterans are higher than those of the general US population. Although veterans compose only 7.6% of the US population, nearly 14% of American adult suicides are among veterans. The rate of suicide is 1.5 times higher among all veterans and 2.1 times higher among female veterans compared with the general population. Only 47% of all veterans are enrolled in the US Department of Veterans Affairs (VA) Healthcare System, leaving a large number either not receiving health care or receiving it outside the VA. Recent legislation has improved access to care for veterans outside the VA, highlighting the need for a broad public health approach to address veteran suicide and the need for all health care institutions and clinicians to be familiar with the unique health concerns in this population. The purpose of this narrative review was to summarize the risk factors contributing to veteran suicide and to provide guidance on how to assess and mitigate these risks. Suicide is preventable through recognition of risk and prompt intervention. Health care providers both inside and outside the VA system are uniquely situated at the intersection of the many contributing factors to veteran suicide and should have a structured, proactive approach to address the problem.

Association of War Zone-Related Stress With Alterations in Limbic Gray Matter Microstructure

IMPORTANCE

Military service members returning from theaters of war are at increased risk for mental illness, but despite high prevalence and substantial individual and societal burden, the underlying pathomechanisms remain largely unknown. Exposure to high levels of emotional stress in theaters of war and mild traumatic brain injury (mTBI) are presumed factors associated with risk for the development of mental disorders.

OBJECTIVE

To investigate (1) whether war zone-related stress is associated with microstructural alterations in limbic gray matter (GM) independent of mental disorders common in this population, (2) whether associations between war zone-related stress and limbic GM microstructure are modulated by a history of mTBI, and (3) whether alterations in limbic GM microstructure are associated with neuropsychological functioning.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was part of the TRACTS (Translational Research Center for TBI and Stress Disorders) study, which took place in 2010 to 2014 at the Veterans Affair Rehabilitation Research and Development TBI National Network Research Center. Participants included male veterans (aged 18-65 years) with available diffusion tensor imaging data enrolled in the TRACTS study. Data analysis was performed between December 2017 to September 2021.

EXPOSURES

The Deployment Risk and Resilience Inventory (DRRI) was used to measure exposure to war zone-related stress. The Boston Assessment of TBI-Lifetime was used to assess history of mTBI. Stroop Inhibition (Stroop-IN) and Inhibition/Switching (Stroop-IS) Total Error Scaled Scores were used to assess executive or attentional control functions.

MAIN OUTCOMES AND MEASURES

Diffusion characteristics (fractional anisotropy of tissue [FAT]) of 16 limbic and paralimbic GM regions and measures of functional outcome.

RESULTS

Among 384 male veterans recruited, 168 (mean [SD] age, 31.4 [7.4] years) were analyzed. Greater war zone-related stress was associated with lower FAT in the cingulate (DRRI-combat left: P = .002, partial r = -0.289; DRRI-combat right: P = .02, partial r = -0.216; DRRI-aftermath left: P = .004, partial r = -0.281; DRRI-aftermath right: P = .02, partial r = -0.219), orbitofrontal (DRRI-combat left medial orbitofrontal cortex: P = .02, partial r = -0.222; DRRI-combat right medial orbitofrontal cortex: P = .005, partial r = -0.256; DRRI-aftermath left medial orbitofrontal cortex: P = .02, partial r = -0.214; DRRI-aftermath right medial orbitofrontal cortex: P = .005, partial r = -0.260; DRRI-aftermath right lateral orbitofrontal cortex: P = .03, partial r = -0.196), and parahippocampal (DRRI-aftermath right: P = .03, partial r = -0.191) gyrus, as well as with higher FAT in the amygdala-hippocampus complex (DRRI-combat: P = .005, partial r = 0.254; DRRI-aftermath: P = .02, partial r = 0.223). Lower FAT in the cingulate-orbitofrontal gyri was associated with impaired response inhibition (Stroop-IS left cingulate: P < .001, partial r = -0.440; Stroop-IS right cingulate: P < .001, partial r = -0.372; Stroop-IS left medial orbitofrontal cortex: P < .001, partial r = -0.304; Stroop-IS right medial orbitofrontal cortex: P < .001, partial r = -0.340; Stroop-IN left cingulate: P < .001, partial r = -0.421; Stroop-IN right cingulate: P < .001, partial r = -0.300; Stroop-IN left medial orbitofrontal cortex: P = .01, partial r = -0.223; Stroop-IN right medial orbitofrontal cortex: P < .001, partial r = -0.343), whereas higher FAT in the mesial temporal regions was associated with improved short-term memory and processing speed (left amygdala-hippocampus complex: P < .001, partial r = -0.574; right amygdala-hippocampus complex: P < .001, partial r = 0.645; short-term memory left amygdala-hippocampus complex: P < .001, partial r = 0.570; short-term memory right amygdala-hippocampus complex: P < .001, partial r = 0.633). A history of mTBI did not modulate the association between war zone-related stress and GM diffusion.

CONCLUSIONS AND RELEVANCE

This study revealed an association between war zone-related stress and alteration of limbic GM microstructure, which was associated with cognitive functioning. These results suggest that altered limbic GM microstructure may underlie the deleterious outcomes of war zone-related stress on brain health. Military service members may benefit from early therapeutic interventions after deployment to a war zone.

Factors Increasing Risk of Suicide after Traumatic Brain Injury: A State-of-the-Science Review of Military and Civilian Studies

Primary Objective: Survey TBI literature to identify evidence of risk for post-injury suicide.Literature Selection: Search terms ((traumatic brain injury OR TBI) AND (suicidality OR suicidal behaviour OR suicidal ideation)) entered in PubMed, OVID Medline, PsychInfo, and Web of Science for papers published in print 01/01/1997 to 06/30/2019.Analysis of Literature: Authors screened abstracts, excluding duplicates and articles not meeting inclusion/exclusion criteria. Full papers were reviewed to make final exclusions. Data were extracted from 40 papers included co- and premorbid disorders, demographics, injury-related and psychological factors.Results: Persons with TBI have a higher risk for suicide than the general population. Reviewed articles reported comorbid depression and/or PTSD as risk factors for post-TBI suicide. Co- or premorbid substance misuse, sex, and sleep disturbance moderate risk. Quality of the literature was limited by sample size, the predominance of male participants, and inconsistency in reporting of findings.Conclusions: Comorbid depression and PTSD are significant post-TBI risk factors for suicide. Several variables combine to moderate or mediate TBI's connection with suicide. Civilian and military clinician cross-talk and consistent reporting of results from reproducible studies of post-TBI suicide risk factors could improve prevention and treatment efforts in veterans and civilians.

Risk Factors for Suicidal Ideation Following Mild Traumatic Brain Injury: A TRACK-TBI Study

OBJECTIVE

To identify risk factors for suicidal ideation (SI) following mild traumatic brain injury (mTBI).

SETTING

Eleven US level 1 trauma centers.

PARTICIPANTS

A total of 1158 emergency department patients with mTBI (Glasgow Coma Scale score = 13-15) enrolled in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study.

DESIGN

Prospective observational study; weights-adjusted multivariable logistic regression models (n's = 727-883) estimated associations of baseline factors and post-TBI symptoms with SI at 2 weeks and 3, 6, and 12 months postinjury.

MAIN MEASURES

Patient Health Questionnaire, Rivermead Post-Concussion Symptoms Questionnaire.

RESULTS

Preinjury psychiatric history predicted SI at all follow-ups (adjusted odds ratios [AORs] = 2.26-6.33, P values <.05) and history of prior TBI predicted SI at 2 weeks (AOR = 2.36, 95% confidence interval [CI] = 1.16-4.81, P = .018), 3 months (AOR = 2.62, 95% CI = 1.33-5.16, P = .005), and 6 months postinjury (AOR = 2.54, 95% CI = 1.19-5.42, P = .016). Adjusting for these baseline factors, post-TBI symptoms were strongly associated with SI at concurrent (AORs = 1.91-2.88 per standard deviation unit increase in Rivermead Post-Concussion Symptoms Questionnaire score; P values <.0005) and subsequent follow-up visits (AORs = 1.68-2.53; P values <.005). Most of the associations between post-TBI symptoms and SI were statistically explained by co-occurring depression.

CONCLUSION

Screening for psychiatric and prior TBI history may help identify patients at risk for SI following mTBI. Awareness of the strong associations of post-TBI symptoms with SI may facilitate interventions to prevent suicide-related outcomes in patients with mTBI.

Shared correlates of prescription drug misuse and severe suicide ideation among clinical patients at risk for suicide

OBJECTIVE

Unintentional drug overdose and suicide have emerged as public health problems. Prescription drug misuse can elevate risk of overdose. Severe suicidal ideation increases risk of suicide. We identified shared correlates of both risk factors to inform cross-cutting prevention efforts.

METHODS

We conducted a cross-sectional study using the Military Suicide Research Consortium's Common Data Elements survey; 2012-2017 baseline data collected from 10 research sites were analyzed. The sample included 3962 clinical patients at risk of suicide. Factors examined in relation to the outcomes, prescription drug misuse and severe suicidal ideation, included demographic characteristics and symptoms of: hopelessness; anxiety; post-traumatic stress disorder; alcohol use; other substance use; prior head/neck injury; insomnia; and belongingness. Poisson regression models with robust estimates provided adjusted prevalence ratios (aPRs) and 97.5% confidence intervals (CIs).

RESULTS

Medium and high (vs. low) levels of insomnia were positively associated with prescription drug misuse (aPRs p < 0.025). Medium (vs. low) level of insomnia was positively associated with severe suicidal ideation (aPR: 1.09; CI: 1.01-1.18). Medium and high (vs. low) levels of perceived belongingness were inversely associated with both outcomes (aPRs p < 0.025).

CONCLUSIONS

Research should evaluate whether addressing sleep problems and improving belongingness can reduce prescription drug misuse and suicidal ideation simultaneously.

Deployment and Psychological Correlates of Suicide Ideation: A Prospective, Longitudinal Study of Risk and Resilience Among Combat Veterans

INTRODUCTION

Suicide rates among military personnel have risen in part due to war zone deployments. Yet, the degree to which deployment-related stressors, in combination with preexisting and co-occurring psychiatric symptoms and individual resilience factors, contribute to suicide ideation (SI) remains unclear. The current study leverages prospective, longitudinal data to examine both risk and protective factors associated with SI in deployed service members.

MATERIALS AND METHODS

Participants were 1,805 active duty enlisted Marines and Navy service members assessed before and after a 7-month deployment for SI, preexisting and concurrent symptoms of depression, post-traumatic stress disorder (PTSD), alcohol consumption, as well as prior and deployment-related traumatic brain injury (TBI). Current self-reported psychological resilience and social support were analyzed as potential protective factors.

RESULTS

Rates of SI were 7.3% and 3.9% before and after deployment, respectively. Of those with post-deployment SI, 68.6% were new-onset cases. Multivariate regression revealed that concurrent mild depression was the strongest risk factor (odds ratio [OR] = 10.03, 95% CI 5.28-19.07). Other significant risk factors included prior SI (OR = 3.36, 95% CI 1.60-7.05), prior subthreshold PTSD (OR = 2.10, 95% CI 1.10-3.99), and deployment TBI (OR = 1.84, 95% CI 1.03-3.28). Controlling for clinical symptoms and TBI, the risk of SI was reduced for those with moderate (OR = 0.50, 95% CI 0.27-0.93) and high psychological resilience scores (OR = 0.25, 95% CI 0.08-0.79) after deployment.

CONCLUSIONS

Results indicate that even mild symptoms of depression and PTSD may increase the risk of SI. Screening for subthreshold clinical symptoms and TBI while incorporating psychological resilience training would allow for a more multidimensional approach to suicide risk assessment.