Military Deployment May Increase the Risk for Traumatic Brain Injury Following Deployment

Risk of Traumatic Brain Injury in Deployment and Nondeployment Settings Among Members of the Millennium Cohort Study

OBJECTIVE

To describe and quantify the prevalence and risk of deployment and nondeployment service-related traumatic brain injury (TBI) among participants of the Millennium Cohort Study.

SETTING

Survey data.

PARTICIPANTS

28 759 Millennium Cohort Study participants who were active duty, Reserves, or National Guard at the time of the survey.

DESIGN

Cross-sectional secondary data analysis.

MAIN MEASURES

Estimates of prevalence and rates of TBI were calculated. Multivariable Poisson regression estimated rate ratios of TBI overall and stratified by deployment and nondeployment settings.

RESULTS

The rate of TBI over the 362 535 person-years (PY) was 2.95 p/100 PY. the nondeployment rate was 2.15 p/100 PY, with a significantly higher rate (11.38 p/100 PY) in deployment settings. Bullets/blasts were the most common TBI mechanisms in deployed settings, while sports/physical training and military training were common in nondeployed settings.

CONCLUSIONS

The risk of TBI as well as its mechanism varies by deployment and nondeployment, suggesting that targeted prevention strategies are needed to reduce the risk for TBI among military personnel based on their deployment status.

Racial/Ethnic and Geographic Disparities in Comorbid Traumatic Brain Injury-Renal Failure in US Veterans and Associated Veterans Affairs Resource Costs, 2000-2020

Studies have identified disparities by race/ethnicity and geographic status among veterans with traumatic brain injury (TBI) and renal failure (RF). We examined the association of race/ethnicity and geographic status with RF onset in veterans with and without TBI, and the impact of disparities on Veterans Health Administration resource costs.

METHODS

Demographics by TBI and RF status were assessed. We estimated Cox proportional hazards models for progression to RF and generalized estimating equations for inpatient, outpatient, and pharmacy cost annually and time since TBI + RF diagnosis, stratified by age.

RESULTS

Among 596,189 veterans, veterans with TBI progressed faster to RF than those without TBI (HR 1.96). Non-Hispanic Black veterans (HR 1.41) and those in US territories (HR 1.71) progressed faster to RF relative to non-Hispanic Whites and those in urban mainland areas. Non-Hispanic Blacks (-$5,180), Hispanic/Latinos ($-4,984), and veterans in US territories (-$3,740) received fewer annual total VA resources. This was true for all Hispanic/Latinos, while only significant for non-Hispanic Black and US territory veterans < 65 years. For veterans with TBI + RF, higher total resource costs only occurred ≥ 10 years after TBI + RF diagnosis ($32,361), independent of age. Hispanic/Latino veterans ≥ 65 years received $8,248 less than non-Hispanic Whites and veterans living in US territories < 65 years received $37,514 less relative to urban veterans.

CONCLUSION

Concerted efforts to address RF progression in veterans with TBI, especially in non-Hispanic Blacks and those in US territories, are needed. Importantly, culturally appropriate interventions to improve access to care for these groups should be a priority of the Department of Veterans Affairs priority for these groups.

Lifetime Traumatic Brain Injury and Risk of Post-Concussive Symptoms in the Millennium Cohort Study

Traumatic brain injury (TBI) is prevalent among active duty military service members, with studies reporting up to 23% experiencing at least one TBI, with 10-60% of service members reporting at least one subsequent repeat TBI. A TBI has been associated with an increased risk of cumulative effects and long-term neurobehavioral symptoms, impacting operational readiness in the short-term and overall health in the long term. The association between multiple TBI and post-concussive symptoms (PCS), however, defined as symptoms that follow a concussion or TBI, in the military has not been adequately examined. Previous studies in military populations are limited by methodological issues including small sample sizes, the use of non-probability sampling, or failure to include the total number of TBI. To overcome these limitations, we examined the association between the total lifetime number of TBI and total number of PCS among U.S. active duty military service members who participated in the Millennium Cohort Study. A secondary data analysis was conducted using the Millennium Cohort Study's 2014 survey (n = 28,263) responses on self-reported TBI and PCS (e.g., fatigue, restlessness, sleep disturbances, poor concentration, or memory loss). Zero-inflated negative binomial models calculated prevalence ratios (PRs) and 95% confidence intervals (CIs) for the unadjusted and adjusted associations between lifetime TBIs and PCS. A third of military participants reported experiencing one or more TBIs during their lifetime with 72% reporting at least one PCS. As the mean number of PCS increased, mean lifetime TBIs increased. The mean number of PCS by those with four or more TBI (4.63) was more than twice that of those with no lifetime TBI (2.28). One, two, three, and four or more TBI had 1.10 (95% CI: 1.06-1.15), 1.19 (95% CI: 1.14-1.25), 1.23 (95% CI: 1.17-1.30), and 1.30 times (95% CI: 1.24-1.37) higher prevalence of PCS, respectively. The prevalence of PCS was 2.4 (95% CI: 2.32-2.48) times higher in those with post-traumatic stress disorder than their counterparts. Active duty military service members with a history of TBI are more likely to have PCS than those with no history of TBI. These results suggest an elevated prevalence of PCS as the number of TBI increased. This highlights the need for robust, longitudinal studies that can establish a temporal relationship between repetitive TBI and incidence of PCS. These findings have practical relevance for designing both workplace safety prevention measures and treatment options regarding the effect on and from TBI among military personnel.

The diagnostic intersection of cognitive-communication disorders and aphasia secondary to TBI

BACKGROUND & AIMS

The present retrospective study examines veterans and military personnel who have sustained a cognitive-communication deficit/disorder (CCD) and/or aphasia secondary to traumatic brain injury (TBI). The prevalence of each disorder secondary to TBI is identified and demographic factors are analysed to determine whether specific characteristics (age, gender, race and/or ethnicity) differentially influenced diagnosis (CCD or aphasia).

METHODS & PROCEDURES

A retrospective analysis examining the prevalence of CCD and aphasia among US service personnel with a complicated mild-to-severe TBI treated over a 4-year period (1 January 2016-31 December 2019) was conducted. Medical diagnoses and demographic factors were obtained from administrative data repositories and a logistic regression was performed to identify the relationship between demographic factors and diagnoses.

OUTCOMES & RESULTS

Analyses revealed that 8.8% of individuals studied had a secondary diagnosis of CCD (6.9%), aphasia (1.5%) or both (0.4%). This signifies 6863 cases of CCD, 1516 cases of aphasia and 396 cases of CCD and aphasia (dual diagnosis) per 100,000 individuals who have sustained a complicated mild-to-severe TBI. The proportion of cases observed with these diagnoses was consistent with the racial, gender and ethnic demographics of those diagnosed with TBI. Statistical modelling revealed that increased age is predictive of a diagnosis of aphasia relative to CCD.

CONCLUSIONS & IMPLICATIONS

Service personnel sustaining TBIs are at increased risk of communication impairments with deficits observed across all gender, racial and ethnic demographics. CCD is more commonly observed than aphasia, though clinicians should be cognisant of both when performing assessments. Age is a factor that can influence diagnosis.

WHAT THIS PAPER ADDS

What is already known on the subject Military personnel are at increased risk of communication disorders (CCDs) with TBI associated with multiple types of communication impairments including CCD, aphasia, dysarthria and apraxia of speech. What this paper adds to existing knowledge This paper examines CCD and aphasia occurring following TBI. The proportion of observed cases of CCD and aphasia secondary to TBI are calculated over a 4-year period and the prevalence of these disorders is provided. Additionally, statistical modelling is used to identify differences in the diagnosis of CCD relative to aphasia using the demographic factors of age, racial identity and ethnicity. What are the potential or actual clinical implications of this work? CCD is a frequently occurring issue following TBI, and the findings of this study demonstrate that it is a concern observed across gender, racial and ethnic lines. Advanced age is linked with the diagnosis of aphasia relative to CCD following TBI and should be a consideration during evaluation of patients who have sustained significant head trauma.

The association between blast exposure and transdiagnostic health symptoms on systemic inflammation

Chronic elevation of systemic inflammation is observed in a wide range of disorders including PTSD, depression, and traumatic brain injury. Although previous work has demonstrated a link between inflammation and various diagnoses separately, few studies have examined transdiagnostic symptoms and inflammation within the same model. The objective of this study was to examine relationships between psychiatric and health variables and systemic inflammation and to determine whether mild traumatic brain injury (mTBI) and/or exposure to blast munitions moderate these relationships. Confirmatory factor analysis in a large sample (N = 357) of post-9/11 Veterans demonstrated a good fit to a four-factor model reflecting traumatic stress, affective, somatic, and metabolic latent variables. Hierarchical regression models revealed that each of the latent variables were associated with higher levels of systemic inflammation. However, the strongest relationship with inflammation emerged among those who had both war-zone blast exposures and metabolic dysregulation, even after adjusting for mental health latent variables. Exploratory analyses showed that blast exposure was associated with metabolic dysregulation in a dose-response manner, with self-reported closer blast proximity associated with the greatest metabolic dysregulation. Together, these results provide a greater understanding of the types of symptoms most strongly associated with inflammation and underscore the importance of maintaining a healthy lifestyle to reduce the impact of obesity and other metabolic symptoms on future chronic disease in younger to middle-aged Veterans.

Epidemiology, patterns of care and outcomes of traumatic brain injury in deployed military settings: implications for future military operations

BACKGROUND

Traumatic brain injury (TBI) is prevalent and highly morbid among Service Members. A better understanding of TBI epidemiology, outcomes, and care patterns in deployed settings could inform potential approaches to improve TBI diagnosis and management.

METHODS

A retrospective cohort analysis of Service Members who sustained a TBI in deployed settings between 2001 and 2018 was conducted. Among individuals hospitalized with TBI, we compared the demographic characteristics, mechanism of injury, injury type, and severity between combat and non-combat injuries. We compared diagnostic tests and procedures, evacuation patterns, return to duty rates and days in care between individuals with concussion and those with severe TBI.

RESULTS

There were 46,309 Service Members with TBI and 9,412 who were hospitalized; of those hospitalized, 55% (4,343) had isolated concussion and 9% (796) had severe TBI, of whom 17% (132/796) had polytrauma. Overall mortality was 2% and ranged from 0.1% for isolated concussion to 18% for severe TBI. The vast majority of TBI were evacuated by rotary wing to Role 3 or higher, including those with isolated concussion. As compared to severe TBI, individuals with isolated concussion had fewer diagnostic or surgical procedures performed. Only 6% of Service Members with severe TBI were able to return to duty as compared to 54% of those with isolated concussion. TBI resulted in 123,677 lost duty days; individuals with isolated concussion spent a median of 2 days in care and those with severe TBI spent a median of 17 days in care and a median of 6 days in the intensive care unit.

CONCLUSIONS

While most TBI in the deployed setting is mild, TBI is frequently associated with hospitalization and polytrauma. Over-triage of mild TBI is common. Improved TBI capabilities applicable to forward settings will be critical to the success of future multi-domain operations with limitations in air superiority.

LEVEL OF EVIDENCE

Prognostic, Level III.

Multimodal Neurocognitive Screening of Military Personnel With a History of Mild Traumatic Brain Injury Using the Bethesda Eye & Attention Measure

OBJECTIVE

To evaluate a neurocognitive eye tracking task, the Bethesda Eye & Attention Measure (BEAM), for use in cognitive screening of patients with a history of mild traumatic brain injury (TBI).

SETTING

US military TBI rehabilitation clinic.

DESIGN/PARTICIPANTS

Cross-sectional study of 191 military personnel receiving outpatient services related to history of mild TBI. Main measures: BEAM; neuropsychological screening measures of attention, processing speed, executive function, and memory.

RESULTS

Medium effect sizes were found for partial correlations (controlling for age) between key BEAM metrics and neuropsychological screening tests. Linear regression analyses demonstrated that BEAM saccadic eye movements and manual (button press) metrics each provided complementary value in measurement of cognitive performance, above and beyond effects of demographic factors and clinical characteristics.

CONCLUSION

This study provides initial support for the use of BEAM neurocognitive eye tracking in cognitive screening of adults with a history of mild TBI. BEAM saccadic metrics appear to be particularly well-suited for the assessment of visual attention. Study findings also highlight opportunities for greater cognitive sensitivity or testing efficiency that may be missed by tests measuring only one response modality at a time.

Dementia in military and veteran populations: a review of risk factors-traumatic brain injury, post-traumatic stress disorder, deployment, and sleep

The military population face a unique set of risk factors that may increase the risk of being diagnosed with dementia. Traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) have a higher prevalence in this group in comparison to the civilian population. By delving into the individual relationships between TBI and dementia, and PTSD and dementia, we are able to better explore dementia in the military and veteran populations. While there are some inconsistencies in results, the TBI-dementia association has become more widely accepted. Moderate-to-severe TBI has been found to increase the risk of being diagnosed with Alzheimer's disease. A correlation between PTSD and dementia has been established, however, whether or not it is a causal relationship remains unclear. Factors such as blast, combat and chemical exposure may occur during a deployment, along with TBI and/or PTSD diagnosis, and can impact the risk of dementia. However, there is a lack of literature exploring the direct effects of deployment on dementia risk. Sleep problems have been observed to occur in those following TBI, PTSD and deployment. Poor sleep has been associated with possible dementia risk. Although limited studies have focused on the link between sleep and dementia in military and veteran populations, sleep is a valuable factor to study due to its association and interconnection with other military/veteran factors. This review aims to inform of various risk factors to the cognitive health of military members and veterans: TBI, PTSD, deployment, and sleep.

Incidence (2008-2015) of post-traumatic headaches in United States military personnel

Objective: To conduct a descriptive transversal study to evaluate the incidence and demographic characteristics of post-traumatic headache using data from the Defense Medical Epidemiology Database.Methods: A retrospective cohort study was conducted of data from 2008 to 2015 based on the International Classification of Diseases codes for both acute and chronic post-traumatic headache.Results: A total of 17,010 new cases of post-traumatic headaches were diagnosed among active duty military personnel. Reported incidence rates of post-traumatic headaches in the military increased 29-fold over the timeframe analyzed. Males enlisted in the Army were more likely to be diagnosed with post-traumatic headaches than females (O/E = 0.76), other branches, and officers.Conclusion: Findings of this study indicate that there is a significant incidence of post-traumatic headaches in the U.S. military. However, the incidence rates of post-traumatic headaches in the military are much lower than what was expected considering the number of traumatic brain injuries in the United States military reported by the Department of Defense for the same period. Additional research is needed to further evaluate these differences and the impact of PTHs on military personnel.

Best Practices for Progressive Return to Activity after Concussion: Lessons Learned from a Prospective Study of U.S. Military Service Members

Primary care providers can play a crucial role in the clinical management of concussion. However, many providers lack up-to-date information about best practices for rest and return to activity after these injuries. Most research on this topic has been conducted in athletes, and so less is known about how to assist patients with returning to activity in other settings and populations. This article provides a review of best practices for management of progressive return to activity after concussion, with an emphasis on "lessons learned" from the Defense and Veterans Brain Injury Center (DVBIC) Progressive Return to Activity (PRA) study, a multi-site longitudinal research project conducted to evaluate concussion management practices and the effectiveness of provider training on DVBIC clinical recommendations (CRs). Provider clinical practices and patient outcomes were examined at three U.S. military treatment facilities before and after providers completed a standardized training on DVBIC PRA CRs. In summary, research findings provide additional support that concussion recovery can be influenced by patients' activity levels after injury. Patients with concussion may experience poorer outcomes if they return to pre-injury levels of activity too rapidly, but they may also be at risk for prolonged symptoms if they fail to increase activity levels over time after an initial period of rest. Additionally, training primary care providers in return to activity guidelines can result in more effective patient education and better clinical outcomes. This knowledge can be used to inform best practices for progressive return to activity in both civilian and military settings.

Traumatic Brain Injury Following Military Deployment: Evaluation of Diagnosis and Cause of Injury

OBJECTIVE

To evaluate the prevalence of delayed traumatic brain injury (TBI) diagnosis and cause of injury that resulted in a TBI diagnosis after military deployment.

DESIGN

Medical record notes were reviewed in 2016 from a random sample of 1150 US military service members who had their first-time deployment in 2011 and likely sustained a TBI. Location and cause of the injury were extracted from the progress note for analysis.

PARTICIPANTS AND SETTING

Active-duty US military service members who received an International Classification of Diseases, Ninth Revision code for a TBI diagnosis in a military facility.

MAIN OUTCOME MEASURES

Presence of TBI, location of injury, cause of injury, and time of diagnosis with respect to deployment.

RESULTS

The odds of being diagnosed with a deployment-related TBI were 8 times higher during the first 4 weeks upon return from deployment than the subsequent 32 weeks. The likelihood of diagnosing a deployment-sustained TBI during weeks 5 to 32 was 2 times higher than during 33 to 76 weeks following return from deployment. The proportion of deployment-related TBI diagnoses decreased with time following return from deployment but remained above 40% during weeks 33 to 76. Service branch, gender, race, occupation, and time between TBI diagnosis and return from deployment were significant predictors of deployment-related TBIs. Moving motor vehicle, sports, parachute, and being struck by objects were the top causes of injury in garrison (nondeployed setting), whereas blast produced the majority (66%) of all causes of injuries that resulted in a TBI in the deployed setting.

CONCLUSION

The increased incidence rate of a TBI diagnosis following deployment can be attributed to delayed diagnosis of TBI sustained from injuries during deployment. TBIs sustained during deployment can be diagnosed beyond the initial 4 weeks after return from deployment and may continue up to 76 weeks following return from deployment.

Traumatic Brain Injuries: Unreported and Untreated in an Army Population

Introduction

In 2008, it was reported that 19.5% of service members previously deployed experienced a mild traumatic brain injury (mTBI). Fifty-seven percent of those did not seek medical care. It was suggested that concerns with seeking care involved confidentiality and career issues. Objective: This study addressed mTBI history, medical treatment history, and stigmas associated with mTBI/concussion.

Materials and Methods

An anonymous questionnaire was developed. Data collection occurred throughout March 2018 in conjunction with Brain Injury Awareness Month activities.

Results

All 5,174 volunteers were Army; 86% male; 87% were between 18 and 34 years old; 89% had &lt;14 years in the military; 35% had a combat deployment; and 10% reported having one or more mTBIs in their military careers. Of the Soldiers who reported a concussion, 52% sought medical care. Of those not seeking care, 64% reported they did not think the injury required care, followed by 18% fearing negative impact on their career. Twenty-eight percent who experienced an mTBI versus 11% who have not reported that there is a stigma associated with an mTBI.

Conclusions

Soldiers sometimes failed to report their suspected concussions and did not seek medical care. Educational efforts may increase reporting of and medical screening for potentially concussive events. Future research to determine the ramifications of unreported and untreated mTBIs/concussions is recommended.

The Effect of Traumatic Brain Injury (TBI) on Cognitive Performance in a Sample of Active Duty U.S. Military Service Members

Introduction

Traumatic brain injury (TBI) is considered a signature injury from the fighting in Iraq and Afghanistan. Since the year 2000, over 370,000 U.S. active duty service members have been diagnosed with TBI. Although prior research has shown that even mild forms of TBI are associated with impaired cognitive performance, it is not clear which facets of cognition (computation, memory, reasoning, etc.) are impacted by injury.

Method

In the present study, we compared active duty military volunteers (n = 88) with and without TBI on six measures of cognition using the Automated Neuropsychological Assessment Metric software.

Results

Healthy volunteers exhibited significantly faster response times on the matching-to-sample, mathematical processing, and second round of simple reaction time tasks and had higher throughput scores on the mathematical processing and the second round of the simple reaction time tasks (P &lt; 0.05).

Conclusion

In this population, cognitive impairments associated with TBI influenced performance requiring working memory and basic neural processing (speed/efficiency).

The Relationship between Suicidal Responses and Traumatic Brain Injury and Severe Insomnia in Active Duty, Veteran, and Civilian Populations

This study examined how a positive traumatic brain injury (TBI) screening and insomnia severity relate to suicidal outcomes across active duty, veteran, and civilian samples. Data were used from 3,993 participants from 19 studies. We conducted a series of analyses by group to identify which significantly differed on the variables of interest. TBI and insomnia each had independent relationships with outcomes over and above the impact of the other factor. Veterans presented as clinically worse across the outcomes. However, the relationship between insomnia and suicidal responses was stronger for active duty military compared to veterans. Continued research on TBIs and insomnia severity across groups will improve quality of care for those at risk of suicide.

Incretin Mimetics as Rational Candidates for the Treatment of Traumatic Brain Injury

Traumatic brain injury (TBI) is becoming an increasing public health issue. With an annually estimated 1.7 million TBIs in the United States (U.S) and nearly 70 million worldwide, the injury, isolated or compounded with others, is a major cause of short- and long-term disability and mortality. This, along with no specific treatment, has made exploration of TBI therapies a priority of the health system. Age and sex differences create a spectrum of vulnerability to TBI, with highest prevalence among younger and older populations. Increased public interest in the long-term effects and prevention of TBI have recently reached peaks, with media attention bringing heightened awareness to sport and war related head injuries. Along with short-term issues, TBI can increase the likelihood for development of long-term neurodegenerative disorders. A growing body of literature supports the use of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and glucagon (Gcg) receptor (R) agonists, along with unimolecular combinations of these therapies, for their potent neurotrophic/neuroprotective activities across a variety of cellular and animal models of chronic neurodegenerative diseases (Alzheimer's and Parkinson's diseases) and acute cerebrovascular disorders (stroke). Mild or moderate TBI shares many of the hallmarks of these conditions; recent work provides evidence that use of these compounds is an effective strategy for its treatment. Safety and efficacy of many incretin-based therapies (GLP-1 and GIP) have been demonstrated in humans for the treatment of type 2 diabetes mellitus (T2DM), making these compounds ideal for rapid evaluation in clinical trials of mild and moderate TBI.

Longitudinal Associations among Posttraumatic Stress Disorder Symptoms, Traumatic Brain Injury, and Neurocognitive Functioning in Army Soldiers Deployed to the Iraq War

OBJECTIVES

Military deployment is associated with increased risk of adverse emotional and cognitive outcomes. Longitudinal associations involving posttraumatic stress disorder (PTSD), relatively mild traumatic brain injury (TBI), and neurocognitive compromise are poorly understood, especially with regard to long-term outcomes, and rigorous research is necessary to better understand the corresponding relationships. The objective of this study was to examine short-term and long-term (>5 years) longitudinal associations among PTSD, neurocognitive performance, and TBI following military deployment.

METHODS

In this prospective study, N=315 U.S. Army soldiers were assessed at military installations before (2003-2005) and after (2004-2006) an index deployment to the Iraq War, and again an average of 7.6 years later (2010-2014) as a nationally dispersed cohort of active duty soldiers, reservists, and veterans. Thus, the study design allowed for two measurement intervals over which to examine changes. All assessments included the PTSD Checklist, civilian version, and individually-administered performance-based neurocognitive tests. TBI history was derived from clinical interview.

RESULTS

Autoregressive analyses indicated that visual reproduction scores were inversely related to subsequent PTSD symptom severity at subsequent assessments. Conversely, increases in PTSD symptom severity over each measurement interval were associated with poorer verbal and/or visual recall at the end of each interval, and less efficient reaction time at post-deployment. TBI, primarily mild in this sample, was associated with adverse PTSD symptom outcomes at both post-deployment and long-term follow-up.

CONCLUSIONS

These results suggest longitudinal relationships among PTSD symptoms, TBI, and neurocognitive decrements may contribute to sustained emotional and neurocognitive symptoms over time. (JINS, 2018, 24, 311-323).

Role of Department of Defense Policies in Identifying Traumatic Brain Injuries Among Deployed US Service Members, 2001-2016

OBJECTIVES

To examine the role of Department of Defense policies in identifying theater-sustained traumatic brain injuries (TBIs).

METHODS

We conducted a retrospective study of 48 172 US military service members who sustained their first lifetime TBIs between 2001 and 2016 while deployed to Afghanistan or Iraq. We used multivariable negative binomial models to examine the changes in TBI incidence rates following the introduction of Department of Defense policies.

RESULTS

Two Army policies encouraging TBI reporting were associated with an increase of 251% and 97% in TBIs identified following their implementation, respectively. Among airmen, the introduction of TBI-specific screening questions to the Post-Deployment Health Assessment was associated with a 78% increase in reported TBIs. The 2010 Department of Defense Directive Type Memorandum 09-033 was associated with another increase of 80% in the likelihood of being identified with a TBI among soldiers, a 51% increase among sailors, and a 124% increase among Marines.

CONCLUSIONS

Department of Defense and service-specific policies introduced between 2006 and 2013 significantly increased the number of battlefield TBIs identified, successfully improving the longstanding problem of underreporting of TBIs.

Traumatic Brain Injury in Iraq and Afghanistan Veterans: New Results From a National Random Sample Study

This study randomly sampled post-9/11 military veterans and reports on causes, predictors, and frequency of traumatic brain injury (TBI) (N=1,388). A total of 17.3% met criteria for TBI during military service, with about one-half reporting multiple head injuries, which were related to higher rates of posttraumatic stress disorder, depression, back pain, and suicidal ideation. The most common mechanisms of TBI included blasts (33.1%), objects hitting head (31.7%), and fall (13.5%). TBI was associated with enlisted rank, male gender, high combat exposure, and sustaining TBI prior to military service. Clinical and research efforts in veterans should consider TBI mechanism, effects of cumulative TBI, and screening for premilitary TBI.

[Formula: see text]Interpreting change on the neurobehavioral symptom inventory and the PTSD checklist in military personnel

OBJECTIVE

The purpose of this study was to examine the prevalence and stability of symptom reporting in a healthy military sample and to develop reliable change indices for two commonly used self-report measures in the military health care system.

PARTICIPANTS AND METHOD

Participants were 215 U.S. active duty service members recruited from Fort Bragg, NC as normal controls as part of a larger study. Participants completed the Neurobehavioral Symptom Inventory (NSI) and Posttraumatic Checklist (PCL) twice, separated by approximately 30 days.

RESULTS

Depending on the endorsement level used (i.e. ratings of 'mild' or greater vs. ratings of 'moderate' or greater), approximately 2-15% of this sample met DSM-IV symptom criteria for Postconcussional Disorder across time points, while 1-6% met DSM-IV symptom criteria for Posttraumatic Stress Disorder. Effect sizes for change from Time 1 to Time 2 on individual symptoms were small (Cohen's d = .01 to .13). The test-retest reliability for the NSI total score was r = .78 and the PCL score was r = .70. An eight-point change in symptom reporting represented reliable change on the NSI total score, with a seven-point change needed on the PCL.

CONCLUSIONS

Postconcussion-like symptoms are not unique to mild TBI and are commonly reported in a healthy soldier sample. It is important for clinicians to use normative data when evaluating a service member or veteran and when evaluating the likelihood that a change in symptom reporting is reliable and clinically meaningful.