Neuropsychological Performance and Subjective Symptom Reporting in Military Service Members With a History of Multiple Concussions: Comparison With a Single Concussion, Posttraumatic Stress Disorder, and Orthopedic Trauma

A review of long-term outcomes of repetitive concussive and subconcussive blast exposures in the military and limitations of the literature

Objective: The purpose of this review is to summarize the long-term cognitive, psychological, fluid biomarker, and neuroimaging outcomes following repetitive concussive and subconcussive blast exposures sustained through a military career. Method/Results: A review of the literature was conducted, with 450 manuscripts originally identified and 44 manuscripts ultimately included in the review. The most robust studies investigating how repetitive concussive and subconcussive exposures related to cognitive performance suggest there is no meaningful impact. Although there are minimal studies that suggest some small impacts on neuroimaging and fluid biomarkers, most findings have been in very small samples and fail to replicate. Both repetitive blast mTBI and subconcussive blasts appeared to be associated with increased self-reported symptoms. Many of the studies suffered from small sample size, failure to correct for multiple comparisons, and inappropriate control groups. Conclusions: Overall, there is little evidence to support that repetitive blast mTBIs or subconcussive blast exposures have a lasting impact on cognition, neuroimaging, or fluid biomarkers. In contrast, there does appear to be a relationship between these exposures and self-reported psychological functioning, though it is unclear what mechanism drives this relationship. Small sample size, lack of correction for multiple comparisons, limited control groups, lack of consideration of important covariates, limited diversity of samples, and lack of reliable and valid measures for assessment of blast exposure are major limitations restricting this research. Patients should be encouraged that while research is ongoing, there is little to currently suggest long-term cognitive or neurological damage following repetitive blast exposure.

Neuropsychological deficit profiles for service members with mild traumatic brain injury

BACKGROUND

Neuropsychological deficits are generally assessed in terms of absolute level of functioning, e.g. high average, average, low average, although there is increased interest in calculating indices of relative degree of decline, e.g. mild, moderate, severe.

OBJECTIVE

To examine differences in demographic, psychiatric, and military-specific characteristics for relative degree of decline in neuropsychological profiles attributed to traumatic brain injuries (TBIs) among service members (SMs).

METHODS

Data were drawn from an existing clinical database of 269 SMs who received neuropsychological evaluations for TBI (Wechsler Test of Adult Reading, Wechsler Adult Intelligence Scale, California Verbal Learning Test, Delis-Kaplan Executive Function System) at a military treatment facility between 2013 and 2018. Independent sample t-tests and one-way ANOVA tests with pairwise comparisons were performed.

RESULTS

Memory and problem-solving abilities were the most and least affected domains, respectively. Greater relative decline was observed among male and White SMs and those with post-traumatic stress disorder (PTSD). By contrast, there were no differences in relative decline according to military rank or work status.

CONCLUSION

Relative degree of decline after TBI among SMs is differentially impacted according to neuropsychological domain, with greater impairment among male and White SMs as well as those with PTSD.

Head Trauma and Concussions in Film and Television Stunt Performers: An Exploratory Study

OBJECTIVES

The aims of the study were to assess prevalence and management of head impacts in stunt performers and to evaluate performers' quality of life and ability to work after head injury.

METHODS

Stunt performers completed an online survey about head impacts/head whips history, diagnosed concussions, reasons for not reporting injuries, health care sought after head impacts, attitudes toward on-set concussion management, perceived ability to work as a stunt performer, and health-related quality of life.

RESULTS

One hundred seventy-three performers (80%) indicated at least one head impact/head whip during their stunt career. Of these, 86% exhibited concussion-like symptoms and 38% received one or more concussion diagnoses. Sixty-five percent continued working with concussion-like symptoms. Short Form-12 mental component scores were suggestive of depression in 42%.

CONCLUSIONS

Concussion seems to be a serious occupational health issue in stunt performers. We suggest that concussion management, risk reduction, and education should be addressed in this community.

Concussion coach for postconcussive symptoms: A randomized, controlled trial of a smartphone application with Afghanistan and Iraq war Veterans

Objective: Investigate the effectiveness of Concussion Coach, an interactive smartphone application, as a treatment for residual neurobehavioral symptoms and distress in Veterans with a history of mild traumatic brain injury (mild TBI). Methods: Veterans with mild TBI were randomized to Concussion Coach (n = 238) or Treatment-as-Usual (TAU) (n = 241) in a 3-month randomized controlled trial. Primary outcome measures included postconcussive symptom (PCS) severity as measured by the Neurobehavioral Symptom Inventory (NSI), and psychological distress as measured by the Brief Symptom Inventory-18 (BSI-18). Measures of self-efficacy, social support, and comfort with technology were administered as potential moderators and mediators. An intention-to-treat (ITT) analysis was performed (N = 461: Concussion Coach = 231 and TAU = 230) using Bayesian Network (BN)modeling. Results: The probability of decreased PCS severity was significantly greater for those assigned to Concussion Coach, .35 [.32,.37], than for TAU, .29 (.27, .32), with an odds ratio (OR) of 1.29. Also, Concussion Coach showed a significantly greater probability of increased self-efficacy (.36 [.32, .39]) than did TAU (.28 [.25, .30], OR = 1.42). In turn, self-efficacy (increased vs. decreased) showed a significantly greater probability of decreased PCS severity (.51 [.47, .54] vs. .27 [.24, .30], OR = 2.71) and decreased psychological distress (.53 [.49, .56] vs. .32 [.29, .35], OR = 2.35), suggesting that self-efficacy may have mediated Concussion Coach effects. Conclusions: Concussion Coach is effective at reducing PCS severity and psychological distress. Increased self-efficacy/perception of self-management of symptoms may be key to successful treatment of residual symptoms in those with history of concussion.

Optimizing Concussion Care Seeking: The Influence of Previous Concussion Diagnosis Status on Baseline Assessment Outcomes

BACKGROUND

The prevalence of unreported concussions is high, and undiagnosed concussions can lead to worse postconcussion outcomes. It is not clear how those with a history of undiagnosed concussion perform on subsequent standard concussion baseline assessments.

PURPOSE

To determine if previous concussion diagnosis status was associated with outcomes on the standard baseline concussion assessment battery.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Concussion Assessment, Research, and Education (CARE) Consortium participants (N = 29,934) self-reported concussion history with diagnosis status and completed standard baseline concussion assessments, including assessments for symptoms, mental status, balance, and neurocognition. Multiple linear regression models were used to estimate mean differences and 95% CIs among concussion history groups (no concussion history [n = 23,037; 77.0%], all previous concussions diagnosed [n = 5315; 17.8%], ≥1 previous concussions undiagnosed [n = 1582; 5.3%]) at baseline for all outcomes except symptom severity and Brief Symptom Inventory-18 (BSI-18) score, in which negative binomial models were used to calculate incidence rate ratios (IRRs). All models were adjusted for sex, race, ethnicity, sport contact level, and concussion count. Mean differences with 95% CIs excluding 0.00 and at least a small effect size (≥0.20), and those IRRs with 95% CIs excluding 1.00 and at least a small association (IRR, ≥1.10) were considered significant.

RESULTS

The ≥1 previous concussions undiagnosed group reported significantly greater symptom severity scores (IRR, ≥1.38) and BSI-18 (IRR, ≥1.31) scores relative to the no concussion history and all previous concussions diagnosed groups. The ≥1 previous concussions undiagnosed group performed significantly worse on 6 neurocognitive assessments while performing better on only 2 compared with the no concussion history and all previous concussions diagnosed groups. There were no between-group differences on mental status or balance assessments.

CONCLUSION

An undiagnosed concussion history was associated with worse clinical indicators at future baseline assessments. Individuals reporting ≥1 previous undiagnosed concussions exhibited worse baseline clinical indicators. This may suggest that concussion-related harm may be exacerbated when injuries are not diagnosed.

Independent and Synergistic Associations Between TBI Characteristics and PTSD Symptom Clusters on Cognitive Performance and Postconcussive Symptoms in Iraq and Afghanistan Veterans

OBJECTIVE

The investigators sought to evaluate the independent and interactive associations between mild traumatic brain injury (mTBI) characteristics and posttraumatic stress disorder (PTSD) symptoms with regard to postconcussive symptoms and cognition among treatment-seeking veterans of the U.S. conflicts in Iraq and Afghanistan.

METHODS

Sixty-seven Iraq and Afghanistan veterans who had a history of mTBI and comorbid PTSD were grouped based on injury mechanism (blast versus nonblast) and number of lifetime mTBIs (one to two versus three or more). Independent associations between mTBI characteristics and PTSD symptom clusters were evaluated with regard to cognition and postconcussive symptoms. Follow-up analyses were conducted to determine any interactive associations between TBI characteristics and PTSD symptom clusters.

RESULTS

Higher PTSD symptoms, particularly hyperarousal, were associated with poorer executive functioning and higher postconcussive symptoms. No direct relationships were observed between PTSD symptom clusters and memory or processing speed. The relationship between hyperarousal and processing speed was moderated by lifetime mTBIs, such that those with a history of at least three mTBIs demonstrated a negative association between hyperarousal and processing speed. Blast-related mTBI history was associated with reduced processing speed, compared with non-blast-related mTBI. However, an interaction was observed such that among those with blast-related mTBI history, higher re-experiencing symptoms were associated with poorer processing speed, whereas veterans without history of blast-related mTBI did not demonstrate an association between processing speed and re-experiencing symptoms.

CONCLUSIONS

Higher hyperarousal and re-experiencing symptoms were associated with reduced processing speed among veterans with repetitive and blast-related mTBI history, respectively. PTSD symptoms, specifically hyperarousal, were associated with poorer executive functioning and higher postconcussive symptoms. Limited associations were found between injury characteristics and cognition chronically following mTBI. However, these results support synergistic effects of specific PTSD symptom clusters and TBI characteristics.

Empirical Analysis of the Nursing Effect of Intelligent Medical Internet of Things in Postoperative Osteoarthritis

In order to analyze the effect of postoperative nursing for bones and joints, this paper combines the intelligent medical Internet of Things technology to construct a postoperative nursing system for bones and joints and conducts research on postoperative nursing methods for bones and joints. Moreover, this paper realizes the integration of "voice data + video data + software data" and the integration of "wired network + RFID sensor network + WIFI wireless network." In this paper, this paper constructs an intelligent medical IoT nursing analysis system, combines actual cases to analyze the effect of postoperative nursing of bones and joints, and selects an intelligent IoT system and statistical software SPSS23.0 to complete statistical processing.

Clinical Research of Orthopedic Trauma Based on Computer 3D Image Analysis

In order to improve the clinical research effect of orthopedic trauma, this paper applies computer 3D image analysis technology to the clinical research of orthopedic trauma and proposes the BOS technology based on FFT phase extraction. The background image in this technique is a "cosine blob" background image. Moreover, this technology uses the FFT phase extraction method to process this background image to extract the image point displacement. The BOS technology based on FFT phase extraction does not need to select a diagnostic window. Finally, this paper combines computer 3D image analysis technology to build an intelligent system. According to the experimental research results, the clinical analysis system of orthopedic trauma based on computer 3D image analysis proposed in this paper can play an important role in the clinical diagnosis and treatment of orthopedic trauma and improve the diagnosis and treatment effect of orthopedic trauma.

Number of Concussions Does Not Affect Treatment Response to Cognitive Rehabilitation Interventions Following Mild TBI in Military Service Members

OBJECTIVE

The study objective was to determine whether number of concussions would affect symptom improvement following cognitive rehabilitation (CR) interventions.

METHOD

Service members (N = 126) with concussion history completed a 6-week randomized control trial of CR interventions. Participants were stratified based on self-reported lifetime concussion frequency. Outcome measures included the Paced Auditory Serial Addition Test (PASAT), the Global Severity Index (GSI) from the Symptom Checklist-90-Revised, and the Key Behaviors Change Inventory (KBCI).

RESULTS

Mixed-model analyses of variance revealed a significant main effect for time on cognitive, psychological, and neurobehavioral functioning. A significant main effect for the number of concussions was observed for GSI and KBCI, but not PASAT. Interactions between the number of concussions and time were not significant for any of the outcome variables.

CONCLUSIONS

Over the 6-week interval, improvements were found for all participants across all outcome measures. Number of concussions did not affect improvements over time.

Differential effects of deployment and nondeployment mild TBI on neuropsychological outcomes

Objective: Mild traumatic brain injury (TBI) that occurs in a deployment environment is characteristically different from mild TBI that occurs outside of deployment. This study evaluated differential and interaction effects of deployment and nondeployment mild TBI on cognitive and behavioral health outcomes. Research Method: Combat veterans (N = 293) who passed performance-validity measures completed the Mid-Atlantic MIRECC Assessment of TBI (MMA-TBI), Clinician-Administered Posttraumatic Stress Disorder (PTSD) Scale (CAPS-5), a neuropsychological assessment battery, and self-report questionnaires. A 2 × 2 × 2 analysis of variance (ANOVA) was conducted to evaluate the main and interaction effects across mild TBI groups and PTSD diagnosis. Results: Deployment TBI was associated with poorer outcomes on several cognitive tests: Wechsler Adult Intelligence Scale, 4th edition (WAIS-IV); Working Memory Index (WMI; p = .018); Trail Making Test A (TMT-A; p < .001); and Trail Making Test B (TMT-B; p = .002). Deployment TBI and PTSD were also associated with increased PTSD, depressive, and neurobehavioral symptoms; pain interference; and poorer sleep quality. Nondeployment TBI had no effect on cognitive performance and was associated only with poorer sleep quality. PTSD had the strongest associations with symptom measures and deployment TBI with cognitive outcomes. There were no significant interaction effects after adjusting for multiple comparisons. Conclusions: Remote outcomes associated with mild deployment TBI are different from those associated with nondeployment mild TBI and are robust beyond PTSD. This suggests that the environment surrounding a TBI event influences cognitive and symptom sequelae. Veterans who experience mild TBI during deployment may report changes in cognition, but most will continue to function within the expected range. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Coordinating Global Multi-Site Studies of Military-Relevant Traumatic Brain Injury: Opportunities, Challenges, and Harmonization Guidelines

Traumatic brain injury (TBI) is common among military personnel and the civilian population and is often followed by a heterogeneous array of clinical, cognitive, behavioral, mood, and neuroimaging changes. Unlike many neurological disorders that have a characteristic abnormal central neurologic area(s) of abnormality pathognomonic to the disorder, a sufficient head impact may cause focal, multifocal, diffuse or combination of injury to the brain. This inconsistent presentation makes it difficult to establish or validate biological and imaging markers that could help improve diagnostic and prognostic accuracy in this patient population. The purpose of this manuscript is to describe both the challenges and opportunities when conducting military-relevant TBI research and introduce the Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Military Brain Injury working group. ENIGMA is a worldwide consortium focused on improving replicability and analytical power through data sharing and collaboration. In this paper, we discuss challenges affecting efforts to aggregate data in this patient group. In addition, we highlight how "big data" approaches might be used to understand better the role that each of these variables might play in the imaging and functional phenotypes of TBI in Service member and Veteran populations, and how data may be used to examine important military specific issues such as return to duty, the late effects of combat-related injury, and alteration of the natural aging processes.

Predicting military readiness using objective and subjective indices of neuropsychological impairment in service members with mild traumatic brain injury

The military is interested in identifying factors to improve the readiness of service members with traumatic brain injury (TBI). TBI outcome studies have primarily used objective neuropsychological data interpreted using the absolute level of functioning (i.e., high average, average, low average), though research suggests it is also important to consider other objective indices of the relative degree of decline (e.g., mild, moderate, severe) and subjective complaints. The current study determined the predictive ability of objective indices of neuropsychological functioning (i.e., absolute level and the relative degree of decline) and subjective complaints (i.e., Neurobehavioral Symptom Inventory) in terms of military work status (i.e., return to duty, medically disabled, retired) for 113 service members with mild TBI. ANOVAs and post-hoc tests indicated individuals who were able to return to duty had higher absolute indices and lower relative decline scores in working memory and overall intelligence, as well as lower subjective neuropsychological complaints when compared to those who were disabled or retired. Multinomial logistic regression models generally supported these findings, except relative decline scores were not predictive of military work status likely due to issues of collinearity (i.e., relative decline scores are calculated using absolute scores). In conclusion, indices of absolute functioning and subjective neuropsychological impairments appear to be predictors of the ability to return to duty post-TBI in military populations, emphasizing the need to focus on cognitive reserve and emotional resilience as potential interventions.

Associations Between Multiple Remote Mild TBIs and Objective Neuropsychological Functioning and Subjective Symptoms in Combat-Exposed Veterans

OBJECTIVE

The purpose of this study was to evaluate relationships between multiple mild traumatic brain injuries (mTBIs) and objective and subjective clinical outcomes in a sample of combat-exposed Veterans, adjusting for psychiatric distress and combat exposure.

METHOD

In this cross-sectional study, 73 combat-exposed Iraq/Afghanistan Veterans were divided into three groups based on mTBI history: 0 mTBIs (n = 31), 1-2 mTBIs (n = 21), and 3+ mTBIs (n = 21). Veterans with mTBI were assessed, on average, 7.78 years following their most recent mTBI. Participants underwent neuropsychological testing and completed self-report measures assessing neurobehavioral, sleep, and pain symptoms.

RESULTS

MANCOVAs adjusting for psychiatric distress and combat exposure showed no group differences on objective measures of attention/working memory, executive functioning, memory, and processing speed (all p's > .05; ηp2 = .00-.06). In contrast, there were significant group differences on neurobehavioral symptoms (p's = < .001-.036; ηp2 = .09-.43), sleep difficulties (p = .037; ηp2 = .09), and pain symptoms (p < .001; ηp2 = .21). Pairwise comparisons generally showed that the 3+ mTBI group self-reported the most severe symptoms, followed by comparable symptom reporting between the 0 and 1-2 mTBI groups.

CONCLUSIONS

History of multiple, remote mTBIs is associated with elevated subjective symptoms but not objective neuropsychological functioning in combat-exposed Veterans. These results advance understanding of the long-term consequences of repetitive mTBI in this population and suggest that Veterans with 3+ mTBIs may especially benefit from tailored treatments aimed at ameliorating specific neurobehavioral, sleep, and pain symptoms.

Neuropsychological Impact of Trauma-Related Mental Illnesses: A Systematic Review of Clinically Meaningful Results

A trauma history is present in approximately 90% of adults in the United States. Comparatively, lifetime post-traumatic stress disorder (PTSD) prevalence is only 8.3% (Kilpatrick et al. Journal of Traumatic Stress, 26, 537-547, 2013). A neuropsychological understanding of trauma is essential to effective trauma-informed assessments and treatments. Prior reviews have focused on PTSD, specific neuropsychological domains, and statistically rather than clinically significant results. The current systematic review investigated standardized test performance across neuropsychological domains in participants with trauma histories and any psychiatric diagnosis. The review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. From 2350 records, the search returned 21 eligible studies: 8 for combat trauma, 2 for childhood trauma, 2 for intimate partner violence and sexual assault, 2 for accidental trauma, 1 for refugee trauma, and 6 for unspecified trauma. Mean neuropsychological scores ranged from low to high average, with one mean verbal memory score in the borderline range. These findings diverge from reports of between-group differences or experimental task performance, which suggest greater levels of static cognitive impairment. Current results are limited by lack of distinction between trauma types in the literature, a dearth of cognitive domains examined, wide use of self-report trauma measures, and publication and outcome reporting biases. Clinical implications for assessment and rehabilitation are discussed in relation to clinical significance, state versus trait based changes, intra-individual variability, changes from pre- to post-trauma, and within-group variability in resilience. Future directions are recommended in consideration of cultural factors, prospective and follow-up designs, and psychiatric diagnosis.

Comparing indices of objective and subjective neuropsychological impairments in service members with mild traumatic brain injury

Neuropsychological impairments are evaluated using subjective measures and objective tests, although their relationship remains unclear. This is likely because objective data is interpreted in terms of absolute level of functioning (e.g., high average, average, low average) while subjective complaints are interpreted in terms of relative decline from premorbid levels (e.g., mild, moderate, severe). The current study calculated objective indices of estimated degree of relative decline (i.e., difference between current cognitive ability and estimated premorbid level) to compare objective and subjective indices of relative decline for military service members with mild traumatic brain injury (mTBI). Contrary to hypotheses, more indices of absolute level of functioning were significantly correlated with subjective neuropsychological (i.e., Neurobehavioral Symptom Inventory) and psychological complaints (e.g., Personality Assessment Inventory) than relative decline scores. The results suggest stronger cognitive abilities may be associated with greater cognitive reserve or emotional resilience and, thereby, less subjective complaints for individuals with TBI, regardless of the extent of neuropsychological decline experienced.

Traumatic Brain Injury and Posttraumatic Stress Disorder: Comorbid Consequences of War

Scientific literature is reviewed supporting a “consequence of war syndrome (CWS)” in Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn soldiers. CWS constituents include chronic pain and insomnia, other physical complaints, posttraumatic stress disorder (PTSD), anxiety, depression, and neuropsychological deficits. The foundation of CWS lies with the chronic stressors inherent to deployment and the cascade of biological events mediated and maintained by hypothalamic-pituitary-adrenal (HPA) axis dysregulation. Such dysregulation is modified by the individual’s specific experiences at war, difficulty reintegrating to post-deployment life, and the onset or exacerbation of the chronic and comorbid physical, emotional, and cognitive disorders. The circuit network between the prefrontal cortex (PFC), amygdala, and hippocampus is particularly sensitive to the consequences of war. The review’s specific conclusions are as follows: HPA axis dysregulation contributes to the chronic insomnia and hyperarousal seen in soldiers. There is considerable symptom overlap between PTSD and blast-related head injury, and it is difficult to determine the relative contributions of the two disorders to abnormal imaging studies. In some cases, traumatic brain injury (TBI) may directly precipitate PTSD symptoms. While not intuitive, the relationship between TBI and postconcussion syndrome appears indirect and mediated through PTSD. Blast-related or conventional head injury may have little long-term impact on neuropsychological functioning; contrarily, PTSD particularly accounts for current cognitive deficits. The psychological experience of CWS includes a “war-within” where soldiers continue to battle an internalized enemy. Successful treatment of CWS entails transdisciplinary care that addresses each of the constituent disorders.

Exploring the factor structure of a battery of neuropsychological assessments among the CENC cohort

OBJECTIVE

The goal of the Chronic Effects of Neurotrauma Consortium (CENC) study is to explore the effects of concussions among Service Members and Veterans. A factor model was fit to selected neuropsychological measures to identify potentially useful relationships between assessments collected on CENC-enrolled participants.

METHOD

492 post-9/11 participants with combat exposure were enrolled across four VA study sites. Participants completed assessments including concussion history, neurocognitive functioning, and self-report questionnaires. Exploratory factor analyses (EFA) using four different methods with varimax and promax rotations were used to analyse the cognitive variables. Final model selection was based on factor loadings towards simple structure.

RESULTS

The scree plot suggested the number of factors to be extracted was between 4 and 5. EFA produced a 5-factor MINRES model with promax rotation that resulted in a factor loading with variables loading on only one factor with a predefined threshold (0.40). Variables loaded on five cognition domains: list learning, working memory/executive skills, cognitive control, fluency, and memory.

CONCLUSION

These results provide reasonable evidence that data collected from the CENC neuropsychological battery can be reduced to five clinically useful factors. This will enable us to use the factors for further study of the impact of concussion on neurodegeneration.