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

The Link between Deployment-Related Injuries and Suicidal Thinking in the Army National Guard: Examining the Role of Perceived Burdensomeness and Hopelessness

OBJECTIVE

In 2020, Army National Guard members demonstrated greater risk of suicide than their military and civilian counterparts. Though literature on deployment-related experiences and suicidal ideation (SI) is mixed, investigations of specific deployment-related experiences (e.g., injuries) may further elucidate the relationship between deployment and suicide risk. Deployment-related injuries, including pain severity and functional impairment, have been linked to increased risk of SI, and correlates like perceived burdensomeness (PB) and hopelessness. The current study sought to examine the cross-sectional relationship between deployment-related injuries, including pain severity and functional impairment, and severity of SI through PB and hopelessness.

METHOD

Immediately post-deployment, Army National Guard members (N = 2,261) completed validated self-report measures on past-week SI, PB, hopelessness, and single items regarding injury sustained during deployment and associated functional impairment and pain severity.

RESULTS

Indirect effect analyses revealed that experience of deployment-related injury was related to SI through PB and hopelessness (R2 = .1993), functional impairment was related to SI through PB, and pain severity was related to SI through PB. Contrary to hypotheses, hopelessness was not associated with SI when PB was simultaneously considered.

CONCLUSIONS

Army National Guard members who develop a sense of PB related to their injury and functional impairment of that injury may be at increased risk for suicidal ideation. Military suicide-prevention efforts may be potentiated through targeting distorted cognitions such as PB and hopelessness, especially in service members who have been injured.

Neuropsychological Correlates of PTSD and Depressive Symptom Improvement in Compensatory Cognitive Training for Veterans With a History of Mild Traumatic Brain Injury

INTRODUCTION

Mild traumatic brain injury (mTBI), depression, and PTSD are highly prevalent in post-9/11 veterans. With the comorbidity of depression and PTSD in post-9/11 veterans with mTBI histories and their role in exacerbating cognitive and emotional dysfunction, interventions addressing cognitive and psychiatric functioning are critical. Compensatory Cognitive Training (CCT) is associated with improvements in prospective memory, attention, and executive functioning and has also yielded small-to-medium treatment effects on PTSD and depressive symptom severity. We sought to examine neuropsychological correlates of PTSD and depressive symptom improvement in veterans with a history of mTBI who received CCT.

MATERIALS AND METHODS

Thirty-seven post-9/11 veterans with mTBI histories and cognitive complaints received 10 weekly 120-minute CCT group sessions. Participants completed a baseline neuropsychological assessment, including tests of premorbid functioning, attention/working memory, processing speed, verbal learning/memory, and executive functioning, and completed psychiatric symptom measures (PTSD and depression) at baseline, post-treatment, and a 5-week follow-up. Paired samples t-tests were used to examine statistically significant changes in PTSD (total and symptom cluster scores) and depressive symptom scores over time. Pearson's correlations were calculated between neuropsychological scores and PTSD and depressive symptom change scores at post-treatment and follow-up. Neuropsychological measures identified as significantly correlated with psychiatric symptom change scores were entered as independent variables in multivariable regression analyses to examine their association with symptom change at post-treatment and follow-up.

RESULTS

Over 50% of CCT participants had clinically meaningful improvement in depressive symptoms (≥17.5% score reduction), and over 20% had clinically meaningful improvement in PTSD symptoms (≥10-point improvement) at post-treatment and follow-up. Examination of PTSD symptom cluster scores revealed a statistically significant improvement in avoidance/numbing at follow-up. Bivariate correlations indicated that worse baseline performance on Category Fluency was moderately associated with PTSD symptom improvement at post-treatment. Worse performance on both Category Fluency and Category Switching Accuracy was associated with improvement in depressive symptoms at post-treatment and follow-up. Worse performance on Trail-Making Number-Letter Switching was also associated with improvement in depressive symptoms at follow-up. Subsequent regression analyses revealed that worse processing speed and worse aspects of executive functioning at baseline were associated with depressive symptom improvement at post-treatment and follow-up.

CONCLUSIONS

Worse baseline performances on tests of processing speed and aspects of executive functioning were significantly associated with improvements in PTSD and depressive symptoms during the trial. Our results suggest that cognitive training may bolster skills that are helpful for PTSD and depressive symptom reduction and that those with worse baseline functioning may benefit more from treatment because they have more room to improve.

Suicide Attempts and Ideation Among Veterans/Service Members and Non-Veterans Over 5 Years Following Traumatic Brain Injury: A Combined NIDILRR and VA TBI Model Systems Study

OBJECTIVE

This study compared rates of suicide attempt (SA) and suicidal ideation (SI) during the first 5 years after traumatic brain injury (TBI) among veterans and service members (V/SMs) in the Veterans Affairs (VA) and the National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR) Model Systems National Databases to each other and to non-veterans (non-Vs) in the NIDILRR database.

SETTING

Twenty-one NIDILRR and 5 VA TBI Model Systems (TBIMS) inpatient rehabilitation facilities in the United States.

PARTICIPANTS

Participants with TBI were discharged from rehabilitation alive, had a known military status recorded (either non-V or history of military service), and successful 1-, 2-, and/or 5-year follow-up interviews completed between 2009 and 2021. The year 1 cohort included 8737 unique participants (8347 with SA data and 3987 with SI data); the year 2 (7628 participants) and year 5 (4837 participants) cohorts both had similar demographic characteristics to the year 1 cohort.

DESIGN

Longitudinal design with data collected across TBIMS centers at 1, 2, and 5 years post-injury.

MAIN OUTCOMES AND MEASURES

History of SA in past year and SI in past 2 weeks assessed by the Patient Health Questionnaire-9 (PHQ-9). Patient demographics, injury characteristics, and rehabilitation outcomes were also assessed.

RESULTS

Full sample rates of SA were 1.9%, 1.5%, and 1.6%, and rates of SI were 9.6%, 10.1%, and 8.7% (respectively at years 1, 2, and 5). There were significant differences among groups based on demographic, injury-related, mental/behavioral health, and functional outcome variables. Characteristics predicting SA/SI related to mental health history, substance use, younger age, lower functional independence, and greater levels of disability.

CONCLUSIONS

Compared with participants with TBI in the NIDILRR system, higher rates of SI among V/SMs with TBI in the VA system appear associated with risk factors observed within this group, including mental/behavioral health characteristics and overall levels of disability.

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.

Magnesium-ibogaine therapy in veterans with traumatic brain injuries

Traumatic brain injury (TBI) is a leading cause of disability. Sequelae can include functional impairments and psychiatric syndromes such as post-traumatic stress disorder (PTSD), depression and anxiety. Special Operations Forces (SOF) veterans (SOVs) may be at an elevated risk for these complications, leading some to seek underexplored treatment alternatives such as the oneirogen ibogaine, a plant-derived compound known to interact with multiple neurotransmitter systems that has been studied primarily as a treatment for substance use disorders. Ibogaine has been associated with instances of fatal cardiac arrhythmia, but coadministration of magnesium may mitigate this concern. In the present study, we report a prospective observational study of the Magnesium-Ibogaine: the Stanford Traumatic Injury to the CNS protocol (MISTIC), provided together with complementary treatment modalities, in 30 male SOVs with predominantly mild TBI. We assessed changes in the World Health Organization Disability Assessment Schedule from baseline to immediately (primary outcome) and 1 month (secondary outcome) after treatment. Additional secondary outcomes included changes in PTSD (Clinician-Administered PTSD Scale for DSM-5), depression (Montgomery-Åsberg Depression Rating Scale) and anxiety (Hamilton Anxiety Rating Scale). MISTIC resulted in significant improvements in functioning both immediately (Pcorrected < 0.001, Cohen's d = 0.74) and 1 month (Pcorrected < 0.001, d = 2.20) after treatment and in PTSD (Pcorrected < 0.001, d = 2.54), depression (Pcorrected < 0.001, d = 2.80) and anxiety (Pcorrected < 0.001, d = 2.13) at 1 month after treatment. There were no unexpected or serious adverse events. Controlled clinical trials to assess safety and efficacy are needed to validate these initial open-label findings. ClinicalTrials.gov registration: NCT04313712 .

Suicide risk profiles among service members and veterans exposed to suicide

OBJECTIVES

Rates of suicide exposure are high among service members and Veterans and are especially concerning given the link between suicide exposure and subsequent suicide risk. However, to date, it is unclear which individuals who are exposed to suicide are subsequently at high risk for suicide. Latent profile analysis (LPA) can provide information on unique risk profiles and subgroups of service members and Veterans who have higher suicide risk after suicide exposure, which has not yet been empirically studied. The purpose of this study was to utilize LPA to identify subgroups of service members and Veterans who are at the highest risk for suicidal thoughts and behaviors following suicide exposure.

METHODS

We analyzed data using LPA from 2570 service members and Veterans (82.1% male, 69.5% White, and 12.1% Latino/a/x) who completed the Military Suicide Research Consortium's Common Data Elements, a battery of self-report suicide-related measures. Psychopathology, substance use, mental health service utilization, interpersonal theory of suicide, and suicide exposure variables were used to validate classes.

RESULTS

Three latent classes emerged from analyses, one low-risk class and two-high risk classes with differing profile compositions (one primarily differentiated by anxiety symptoms and one differentiated by substance use).

CONCLUSION

Class-specific recommendations for suicide prevention efforts will be discussed.

Traumatic brain injury and suicidality among military veterans: The mediating role of social integration

Suicide is a widespread public health concern, including among military Veterans. Traumatic brain injuries (TBIs) and lack of social integration have both been shown to increase risk for suicidality, an outcome that includes, among other suicide-related variables, suicidal ideation, suicide attempts, and suicide death. Interestingly, TBIs have also been identified as a risk factor for social integration problems. In this cross-sectional study we investigated associations between TBI, social integration, and suicidality. Additionally, mediation analysis was used to test whether social integration mediated the association between TBI and suicidality. A sample of 1469 military Veterans (male, n = 1004, 67.2 %; female, n = 457, 32.3 %; transgender/non-binary/prefer not to say, n = 8, 0.5 %) completed an online survey as part of the Military Health and Well-Being Project. TBI was negatively associated with social integration (r = -0.084, p < .001) and positively with suicidality (r = 0.205, p < .001). Social integration was negatively associated with suicidality (r = -0.161, p < .001). Finally, social integration partially mediated the relationship between TBI and social integration (B = 0.121, 95 % CI [0.031-0.23]). This work shows that in the context of TBI, lack of social integration may promote suicidality. It provides support for many theories of suicide which propose social problems as a risk factor of suicide-related outcomes. It further highlights social integration as potential fodder for novel interventions for suicidality, an approach that would have transtheoretical support.

Examining the Relationship Between Sleep Apnea Diagnosis and Suicide Risk in Veterans With Traumatic Brain Injury: A VA TBI Model Systems Study

OBJECTIVE

Obstructive sleep apnea (OSA) is a common sleep disorder in people with traumatic brain injury (TBI). Although sleep disturbances have been associated with an increased risk of suicide compared with the general population, the relationship between OSA and suicide risk after TBI is not well documented. In this study, we hypothesized that OSA diagnosis would predict suicide risk in veterans with TBI.

SETTING

Five Veterans Affairs (VA) Polytrauma Rehabilitation Centers.

PARTICIPANTS

Participants were drawn from the VA TBI Model Systems study, with follow-up interviews at year 1 ( n = 392), year 2 ( n = 444), year 5 ( n = 498), or year 10 ( n = 252) post-TBI (7.8%-14.5% follow-up attrition).

DESIGN

This was a retrospective analysis from observational data using logistic regression with repeated measurements. Suicide ideation and suicide attempts were examined as outcomes at each follow-up to evaluate the relationship between OSA and suicide risk after adjusting for other risk factors determined a priori via literature review.

MAIN MEASURES

Suicidal ideation (Patient Health Questionnaire-9 item 9), suicide attempt during the past year (self-reported), and OSA diagnosis (self-reported).

RESULTS

Contrary to study hypotheses, OSA diagnosis had no statistically significant association with suicide ideation or attempt after accounting for known predictors. However, greater depression symptoms, headache severity, and pre-TBI suicidal ideation and attempts predicted suicide risk at follow-up after accounting for other predictors.

CONCLUSIONS

Results of this study did not support a relationship between OSA and suicide risk, possibly due to methodological limitations of OSA measurement. Future research on this topic should include objective measures of OSA severity and OSA treatment including adherence. Although suicide is a low base rate occurrence, the impact is disastrous and further research is needed to mitigate suicide risk.

Firearm injury prevention counseling for patients with traumatic brain injury: a survey of brain injury physicians

Background

Survivors of traumatic brain injury are at increased risk for firearm-related injuries, including suicide.

Aims

To determine current practices of Brain Injury Medicine (BIM) physicians and their rehabilitation teams in assessing patients' access to firearms and in providing firearm safety education, and the impact of having received training on this topic on physicians' likelihood of inquiring about patients' access to firearms.

Methods

14-item web-based cross-sectional survey of 86 U.S. physiatrists board-certified in BIM.

Results

81% of respondents indicated they believe BIM physicians should counsel their patients on firearm safety but only 12.9% reported always doing so. Fifteen percent reported always inquiring about their patients' access to firearms. 88.2% indicated having never received formal training on firearm injury prevention counseling. Physicians who received such training had 7.5 times higher odds of reporting at least sometimes inquiring about patients' access to firearms than those who were not trained [95% confidence interval (1.94, 28.64)]. They also had 5.7 times higher odds for reporting being at least moderately comfortable providing patients firearm safety counseling [95% CI: (1.39, 23.22)].

Conclusion

While most BIM specialists who responded to this survey believe they should counsel patients on firearm safety, few always or usually do so. Moreover, most do not routinely inquire about their patients' access to firearms. The provision of firearm injury prevention training to BIM physicians was strongly associated with an increased likelihood they will inquire about their patients' access to guns and with an improved comfort level in providing counseling on this subject matter.

Intentional Self-Harm Among US Veterans With Traumatic Brain Injury or Posttraumatic Stress Disorder: Retrospective Cohort Study From 2008 to 2017

BACKGROUND

Veterans with a history of traumatic brain injury (TBI) and/or posttraumatic stress disorder (PTSD) may be at increased risk of suicide attempts and other forms of intentional self-harm as compared to veterans without TBI or PTSD.

OBJECTIVE

Using administrative data from the US Veterans Health Administration (VHA), we studied associations between TBI and PTSD diagnoses, and subsequent diagnoses of intentional self-harm among US veterans who used VHA health care between 2008 and 2017.

METHODS

All veterans with encounters or hospitalizations for intentional self-harm were assigned "index dates" corresponding to the date of the first related visit; among those without intentional self-harm, we randomly selected a date from among the veteran's health care encounters to match the distribution of case index dates over the 10-year period. We then examined the prevalence of TBI and PTSD diagnoses within the 5-year period prior to veterans' index dates. TBI, PTSD, and intentional self-harm were identified using International Classification of Diseases diagnosis and external cause of injury codes from inpatient and outpatient VHA encounters. We stratified analyses by veterans' average yearly VHA utilization in the 5-year period before their index date (low, medium, or high). Variations in prevalence and odds of intentional self-harm diagnoses were compared by veterans' prior TBI and PTSD diagnosis status (TBI only, PTSD only, and comorbid TBI/PTSD) for each VHA utilization stratum. Multivariable models adjusted for age, sex, race, ethnicity, marital status, Department of Veterans Affairs service-connection status, and Charlson Comorbidity Index scores.

RESULTS

About 6.7 million veterans with at least two VHA visits in the 5-year period before their index dates were included in the analyses; 86,644 had at least one intentional self-harm diagnosis during the study period. During the periods prior to veterans' index dates, 93,866 were diagnosed with TBI only; 892,420 with PTSD only; and 102,549 with comorbid TBI/PTSD. Across all three VHA utilization strata, the prevalence of intentional self-harm diagnoses was higher among veterans diagnosed with TBI, PTSD, or TBI/PTSD than among veterans with neither diagnosis. The observed difference was most pronounced among veterans in the high VHA utilization stratum. The prevalence of intentional self-harm was six times higher among those with comorbid TBI/PTSD (6778/58,295, 11.63%) than among veterans with neither TBI nor PTSD (21,979/1,144,991, 1.92%). Adjusted odds ratios suggested that, after accounting for potential confounders, veterans with TBI, PTSD, or comorbid TBI/PTSD had higher odds of self-harm compared to veterans without these diagnoses. Among veterans with high VHA utilization, those with comorbid TBI/PTSD were 4.26 (95% CI 4.15-4.38) times more likely to receive diagnoses for intentional self-harm than veterans with neither diagnosis. This pattern was similar for veterans with low and medium VHA utilization.

CONCLUSIONS

Veterans with TBI and/or PTSD diagnoses, compared to those with neither diagnosis, were substantially more likely to be subsequently diagnosed with intentional self-harm between 2008 and 2017. These associations were most pronounced among veterans who used VHA health care most frequently. These findings suggest a need for suicide prevention efforts targeted at veterans with these diagnoses.

Association between traumatic brain injury and suicidality using a mediation approach and MarketScan

INTRODUCTION

Negative outcomes, including suicidal ideation/attempts, are a major public health concern, particularly among individuals who sustain a traumatic brain injury (TBI). TBI is associated with high rates of postinjury substance use, psychiatric disorders, post-traumatic stress disorder and sleep disturbances. This study examines the mediation effects of substance use, psychiatric disorder and sleep disorder on the associations between TBI and suicidal ideation/attempts.

METHODS

A matched case-control study using data from MarketScan databases for private health insurance and Medicaid from October 2015 to December 2018 estimated the association between TBI and suicidal ideation/attempts using a mediation approach. Individuals less than 65 years of age were included.

RESULTS

In the Medicaid sample, psychiatric disorders mediated 22.4% of the total effect between TBI and suicidal ideation/attempt, while substance use disorders other than opioid use disorder mediated 7.47%. In the private health insurance sample, psychiatric disorders mediated 3.97% of the total effect, opioid use disorders mediated 2.08% of the total effect and sleep disorder mediated 1.25% of the total effect.

CONCLUSIONS

Mediators explained less than 30% of the relationship between TBI and suicidal ideation/attempt. Findings reinforce the importance of primary prevention of TBI and monitoring patients with a TBI for risk of suicide in the first 6-12 months following injury.

Using Machine Learning to Examine Suicidal Ideation After Traumatic Brain Injury: A Traumatic Brain Injury Model Systems National Database Study

OBJECTIVE

The aim of the study was to predict suicidal ideation 1 yr after moderate to severe traumatic brain injury.

DESIGN

This study used a cross-sectional design with data collected through the prospective, longitudinal Traumatic Brain Injury Model Systems network at hospitalization and 1 yr after injury. Participants who completed the Patient Health Questionnaire-9 suicide item at year 1 follow-up ( N = 4328) were included.

RESULTS

A gradient boosting machine algorithm demonstrated the best performance in predicting suicidal ideation 1 yr after traumatic brain injury. Predictors were Patient Health Questionnaire-9 items (except suicidality), Generalized Anxiety Disorder-7 items, and a measure of heavy drinking. Results of the 10-fold cross-validation gradient boosting machine analysis indicated excellent classification performance with an area under the curve of 0.882. Sensitivity was 0.85 and specificity was 0.77. Accuracy was 0.78 (95% confidence interval, 0.77-0.79). Feature importance analyses revealed that depressed mood and guilt were the most important predictors of suicidal ideation, followed by anhedonia, concentration difficulties, and psychomotor disturbance.

CONCLUSIONS

Overall, depression symptoms were most predictive of suicidal ideation. Despite the limited clinical impact of the present findings, machine learning has potential to improve prediction of suicidal behavior, leveraging electronic health record data, to identify individuals at greatest risk, thereby facilitating intervention and optimization of long-term outcomes after traumatic brain injury.

Cytokine Profiles Differentiate Symptomatic from Asymptomatic PTSD in Service Members and Veterans with Chronic Traumatic Brain Injury

Traumatic brain injuries (TBI) and posttraumatic stress disorder (PTSD) are commonly observed comorbid occurrences among military service members and veterans (SMVs). In this cross-sectional study, SMVs with a history of TBI were stratified into symptomatic and asymptomatic PTSD groups based on posttraumatic stress checklist-civilian (PCL-C) total scores. Blood-based biomarkers were assessed, and significant differential markers were associated with scores from multiple neurobehavioral self-report assessments. PCL-C cutoffs were total scores >50 (PTSD symptomatic) and <25 (asymptomatic). Cytokines IL6, IL8, TNFα, and IL10 were significantly elevated (p < 0.05−0.001) in the TBI+/PTSD symptomatic group compared to the TBI+/asymptomatic group. Cytokine levels of IL8, TNFα, and IL10 were strongly associated with PCL-C scores (0.356 < r > 0.624 for all, p < 0.01 for all), while TNFα and IL10 were additionally associated with NSI totals (r = 0.285 and r = 0.270, p < 0.05, respectively). This is the first study focused on PTSD symptom severity to report levels of circulating pro-inflammatory IL8, specifically in SMVs with TBI. These data suggest that within the military TBI population, there are unique cytokine profiles that relate to neurobehavioral outcomes associated with TBI and PTSD.

Mental Health Consequences of Traumatic Brain Injury

Traumatic brain injury (TBI) is associated with a host of psychiatric and neurobehavioral problems. As mortality rates have declined for severe TBI, attention has turned to the cognitive, affective, and behavioral sequelae of injuries across the severity spectrum, which are often more disabling than residual physical effects. Moderate and severe TBI can cause personality changes including impulsivity, severe irritability, affective instability, and apathy. Mild TBI, once considered a largely benign phenomenon, is now known to be associated with a range of affective symptoms, with suicidality, and with worsening or new onset of several psychiatric disorders including posttraumatic stress disorder and major depressive disorder. Repetitive head impacts, often in athletic contexts, are now believed to be associated with a number of emotional and behavioral sequelae. The nature and etiology of mental health manifestations of TBI (including a combination of brain dysfunction and psychological trauma and interrelationships between cognitive, affective, and physical symptoms) are complex and have been a focus of recent epidemiological and mechanistic studies. This paper will review the epidemiology of psychiatric and neurobehavioral problems after TBI in military, civilian, and athletic contexts.

Role of Inflammation in Traumatic Brain Injury-Associated Risk for Neuropsychiatric Disorders: State of the Evidence and Where Do We Go From Here

In the past decade, there has been an increasing awareness that traumatic brain injury (TBI) and concussion substantially increase the risk for developing psychiatric disorders. Even mild TBI increases the risk for depression and anxiety disorders such as posttraumatic stress disorder by two- to threefold, predisposing patients to further functional impairment. This strong epidemiological link supports examination of potential mechanisms driving neuropsychiatric symptom development after TBI. One potential mechanism for increased neuropsychiatric symptoms after TBI is via inflammatory processes, as central nervous system inflammation can last years after initial injury. There is emerging preliminary evidence that TBI patients with posttraumatic stress disorder or depression exhibit increased central and peripheral inflammatory markers compared with TBI patients without these comorbidities. Growing evidence has demonstrated that immune signaling in animals plays an integral role in depressive- and anxiety-like behaviors after severe stress or brain injury. In this review, we will 1) discuss current evidence for chronic inflammation after TBI in the development of neuropsychiatric symptoms, 2) highlight potential microglial activation and cytokine signaling contributions, and 3) discuss potential promise and pitfalls for immune-targeted interventions and biomarker strategies to identify and treat TBI patients with immune-related neuropsychiatric symptoms.

Identifying group-based patterns of suicidal ideation over the first 10 years after moderate-to-severe TBI

OBJECTIVE

To identify group-based patterns in suicidal ideation (SI) over the first 10 years after traumatic brain injury (TBI).

METHODS

Participants included 9539 individuals in the TBI Model Systems National Database who responded to Patient Health Questionnaire-9 Item 9 assessing SI at 1, 2, 5, and/or 10 years post-injury. A k-means cluster analysis was conducted to determine group-based patterns of SI, and pre-injury variables were compared with ANOVAs and chi-square tests.

RESULTS

SI and attempts decreased over time. Four group-based patterns emerged: Low, increasing, moderate, and decreasing SI. The low SI group comprised 89% of the sample, had the highest pre-injury employment, fewer mental health vulnerabilities, least severe injuries, and were oldest. The increasing SI group had the most severe TBIs, were youngest, and disproportionately Black or Asian/Pacific Islander.

CONCLUSION

These findings reinforce the importance of mental health and suicide risk assessment during chronic recovery from TBI.

The Relationship Between Cognitive Functioning and Symptoms of Depression, Anxiety, and Post-Traumatic Stress Disorder in Adults with a Traumatic Brain Injury: a Meta-Analysis

A thorough understanding of the relationship between cognitive test performance and symptoms of depression, anxiety, or post-traumatic stress disorder (PTSD) in people with traumatic brain injury (TBI) is important given the high prevalence of these emotional symptoms following injury. It is also important to understand whether these relationships are affected by TBI severity, and the validity of test performance and symptom report. This meta-analysis was conducted to investigate whether these symptoms are associated with cognitive test performance alterations in adults with a TBI. This meta-analysis was prospectively registered on the PROSPERO International Prospective Register of Systematic Reviews website (registration number: CRD42018089194). The electronic databases Medline, PsycINFO, and CINAHL were searched for journal articles published up until May 2020. In total, 61 studies were included, which enabled calculation of pooled effect sizes for the cognitive domains of immediate memory (verbal and visual), recent memory (verbal and visual), attention, executive function, processing speed, and language. Depression had a small, negative relationship with most cognitive domains. These relationships remained, for the most part, when samples with mild TBI (mTBI)-only were analysed separately, but not for samples with more severe TBI (sTBI)-only. A similar pattern of results was found in the anxiety analysis. PTSD had a small, negative relationship with verbal memory, in samples with mTBI-only. No data were available for the PTSD analysis with sTBI samples. Moderator analyses indicated that the relationships between emotional symptoms and cognitive test performance may be impacted to some degree by exclusion of participants with atypical performance on performance validity tests (PVTs) or symptom validity tests (SVTs), however there were small study numbers and changes in effect size were not statistically significant. These findings are useful in synthesising what is currently known about the relationship between cognitive test performance and emotional symptoms in adults with TBI, demonstrating significant, albeit small, relationships between emotional symptoms and cognitive test performance in multiple domains, in non-military samples. Some of these relationships appeared to be mildly impacted by controlling for performance validity or symptom validity, however this was based on the relatively few studies using validity tests. More research including PVTs and SVTs whilst examining the relationship between emotional symptoms and cognitive outcomes is needed.

Relations among Suicidal Ideation, Depressive Symptoms, and Functional Independence during the Ten Years after Traumatic Brain Injury: A Model Systems Study

OBJECTIVE

To investigate relative causality in relations among suicidal ideation (SI), depressive symptoms, and functional independence over the first 10 years after traumatic brain injury (TBI).

DESIGN

Prospective longitudinal design with data collected through the TBI Model Systems (TBIMS) network at acute rehabilitation hospitalization, as well as 1, 2, 5, and 10 years after injury.

SETTING

United States Level I/II trauma centers and inpatient rehabilitation centers with telephone follow-up.

PARTICIPANTS

Individuals enrolled into the TBIMS National Database (N=9539) with at least one SI score at any follow-up data collection (72.1% male, mean age = 39.39 years).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Patient Health Questionnaire-9 and Functional Independence Measure at years 1, 2, 5, and 10 post-injury.

RESULTS

A cross-lagged panel structural equation model (SEM), which is meant to indirectly infer causality through longitudinal correlational data, suggested that SI, depressive symptoms, and functional independence each significantly predicted themselves over time. Within the model, bivariate correlations among variables were all significant within each time point. Between years 1 and 2 and between years 2 and 5, depressive symptoms had a larger effect on SI than SI had on depressive symptoms. Between years 5 and 10, there was reciprocal causality between the two variables. Functional independence more strongly predicted depressive symptoms than the reverse between years 1 and 2 as well as years 2 and 5, but its unique effects on SI over time were extremely marginal or absent after controlling for depressive symptoms.

CONCLUSIONS

A primary goal for rehabilitation and mental health providers should be to monitor and address elevated symptoms of depression as quickly as possible before they translate into SI, particularly for individuals with TBI who have reduced functional independence. Doing so may be a key to breaking the connection between low functional independence and SI.

Military TBI—What civilian primary care providers should know

In June 2019, the Department of Veterans Affairs (VA) launched the VA Mission Act, which expanded veterans’ health-care access to the private sector. Since civilian primary care providers may see more veterans in their practice, it will be important to understand the unique experiences, comorbidities, and culture of this population in order to provide optimal care. Military service members (SMs) are at an increased risk for traumatic brain injury (TBI), and comorbidities, such as post traumatic stress disorder (PTSD), increasing the likelihood of prolonged symptoms. Military training and repetitive low-level blast exposure may cause symptoms similar to TBI or increase long-term negative effects in SMs. Military culture often has a strong influence in this population. Those who serve in the military identify with military values and have a strong team mentality, which places emphasis on the mission above all else, not accepting defeat, and not ever leaving a fellow SM behind. These values can impact the way a SM/veteran seeks care and/or communicates with his or her health-care provider. Taking a detailed history to understand how these factors apply, as well as screening for mental health comorbidities, are recommended. Understanding the military cultural influences can assist in promoting a stronger therapeutic alliance and encourage more open communication. Ultimately, it is the trusting and respectful relationship between the SM/veteran and the provider that will determine the most effective treatment and result in the most effective resolution of TBI and comorbid symptoms.