Impact of repeated blast exposure on active-duty United States Special Operations Forces

United States (US) Special Operations Forces (SOF) are frequently exposed to explosive blasts in training and combat, but the effects of repeated blast exposure (RBE) on SOF brain health are incompletely understood. Furthermore, there is no diagnostic test to detect brain injury from RBE. As a result, SOF personnel may experience cognitive, physical, and psychological symptoms for which the cause is never identified, and they may return to training or combat during a period of brain vulnerability. In 30 active-duty US SOF, we assessed the relationship between cumulative blast exposure and cognitive performance, psychological health, physical symptoms, blood proteomics, and neuroimaging measures (Connectome structural and diffusion MRI, 7 Tesla functional MRI, [11C]PBR28 translocator protein [TSPO] positron emission tomography [PET]-MRI, and [18F]MK6240 tau PET-MRI), adjusting for age, combat exposure, and blunt head trauma. Higher blast exposure was associated with increased cortical thickness in the left rostral anterior cingulate cortex (rACC), a finding that remained significant after multiple comparison correction. In uncorrected analyses, higher blast exposure was associated with worse health-related quality of life, decreased functional connectivity in the executive control network, decreased TSPO signal in the right rACC, and increased cortical thickness in the right rACC, right insula, and right medial orbitofrontal cortex-nodes of the executive control, salience, and default mode networks. These observations suggest that the rACC may be susceptible to blast overpressure and that a multimodal, network-based diagnostic approach has the potential to detect brain injury associated with RBE in active-duty SOF.

Predictive modeling of initiation and delayed mental health contact for depression

BACKGROUND

Depression is prevalent among Operation Enduring Freedom and Operation Iraqi Freedom (OEF/OIF) Veterans, yet rates of Veteran mental health care utilization remain modest. The current study examined: factors in electronic health records (EHR) associated with lack of treatment initiation and treatment delay; the accuracy of regression and machine learning models to predict initiation of treatment.

METHODS

We obtained data from the VA Corporate Data Warehouse (CDW). EHR data were extracted for 127,423 Veterans who deployed to Iraq/Afghanistan after 9/11 with a positive depression screen and a first depression diagnosis between 2001 and 2021. We also obtained 12-month pre-diagnosis and post-diagnosis patient data. Retrospective cohort analysis was employed to test if predictors can reliably differentiate patients who initiated, delayed, or received no mental health treatment associated with their depression diagnosis.

RESULTS

108,457 Veterans with depression, initiated depression-related care (55,492 Veterans delayed treatment beyond one month). Those who were male, without VA disability benefits, with a mild depression diagnosis, and had a history of psychotherapy were less likely to initiate treatment. Among those who initiated care, those with single and mild depression episodes at baseline, with either PTSD or who lacked comorbidities were more likely to delay treatment for depression. A history of mental health treatment, of an anxiety disorder, and a positive depression screen were each related to faster treatment initiation. Classification of patients was modest (ROC AUC = 0.59 95%CI = 0.586-0.602; machine learning F-measure = 0.46).

CONCLUSIONS

Having VA disability benefits was the strongest predictor of treatment initiation after a depression diagnosis and a history of mental health treatment was the strongest predictor of delayed initiation of treatment. The complexity of the relationship between VA benefits and history of mental health care with treatment initiation after a depression diagnosis is further discussed. Modest classification accuracy with currently known predictors suggests the need to identify additional predictors of successful depression management.

Neurological Effects of Repeated Blast Exposure in Special Operations Personnel

Exposure to blast overpressure has been a pervasive feature of combat-related injuries. Studies exploring the neurological correlates of repeated low-level blast exposure in career "breachers" demonstrated higher levels of tumor necrosis factor alpha (TNFα) and interleukin (IL)-6 and decreases in IL-10 within brain-derived extracellular vesicles (BDEVs). The current pilot study was initiated in partnership with the U.S. Special Operations Command (USSOCOM) to explore whether neuroinflammation is seen within special operators with prior blast exposure. Data were analyzed from 18 service members (SMs), inclusive of 9 blast-exposed special operators with an extensive career history of repeated blast exposures and 9 controls matched by age and duration of service. Neuroinflammation was assessed utilizing positron emission tomography (PET) imaging with [18F]DPA-714. Serum was acquired to assess inflammatory biomarkers within whole serum and BDEVs. The Blast Exposure Threshold Survey (BETS) was acquired to determine blast history. Both self-report and neurocognitive measures were acquired to assess cognition. Similarity-driven Multi-view Linear Reconstruction (SiMLR) was used for joint analysis of acquired data. Analysis of BDEVs indicated significant positive associations with a generalized blast exposure value (GBEV) derived from the BETS. SiMLR-based analyses of neuroimaging demonstrated exposure-related relationships between GBEV, PET-neuroinflammation, cortical thickness, and volume loss within special operators. Affected brain networks included regions associated with memory retrieval and executive functioning, as well as visual and heteromodal processing. Post hoc assessments of cognitive measures failed to demonstrate significant associations with GBEV. This emerging evidence suggests neuroinflammation may be a key feature of the brain response to blast exposure over a career in operational personnel. The common thread of neuroinflammation observed in blast-exposed populations requires further study.

The utility of completing adjuvant video lessons based on the unified protocol during psychotherapy: A retrospective study using a telehealth platform in routine clinical care

Digital supplements to tele-psychotherapy are increasingly needed. The purpose of this retrospective study was to investigate the association between outcomes and the use of supplemental video lessons based on the Unified Protocol (UP), an empirically supported transdiagnostic treatment.

Participants included 7,326 adults in psychotherapy for depression and/or anxiety. Partial correlations were calculated between number of UP video lessons completed and change in outcomes after 10 weeks, controlling for number of therapy sessions and baseline scores. Then, participants were divided into those who did not complete any UP video lessons (n = 2355) and those who completed at least 7/10 video lessons (n = 549), and propensity-matched on 14 covariates. Repeated measures analysis of variance compared these groups (n = 401 in each group) on outcomes.

Among the entire sample, symptom severity decreased as the number of UP video lessons completed increased, with the exception of lessons on avoidance and exposure. Those watching at least 7 lessons showed significantly greater reduction in both depression and anxiety symptoms than those who did not watch any.

Viewing supplemental UP video lessons in addition to tele-psychotherapy had a positive and significant association with symptom improvement and may provide an additional tool for clinicians to implement UP components virtually.

Mental health treatment utilization patterns among 108,457 Afghanistan and Iraq veterans with depression

People with depression often underutilize mental health care. This study was conceived as a first step toward a clinical decision support tool that helps identify patients who are at higher risk of underutilizing care. The primary goals were to (a) describe treatment utilization patterns, early termination, and return to care; (b) identify factors associated with early termination of treatment; and (c) evaluate the accuracy of regression models to predict early termination. These goals were evaluated in a retrospective cohort analysis of 108,457 U.S. veterans who received care from the Veterans Health Administration between 2001 and 2021. Our final sample was 16.5% female with an average age of 34.5. Veterans were included if they had a depression diagnosis, a positive depression screen, and received general health care services at least a year before and after their depression diagnosis. Using treatment quality guidelines, the threshold for treatment underutilization was defined as receiving fewer than four psychotherapy sessions or less than 84 days of antidepressants. Over one fifth of veterans (21.6%) received less than the minimally recommended care for depression. The odds of underutilizing treatment increased with lack of Veterans Administration benefits, male gender, racial/ethnic minority status, and having received mental health treatment in the past (adjusted OR > 1.1). Posttraumatic stress disorder comorbidity correlated with increased depression treatment utilization (adjusted OR < .9). Models with demographic and clinical information from medical records performed modestly in classifying patients who underutilized depression treatment (area under the curve = 0.595, 95% CI [0.588, 0.603]). Most veterans in this cohort received at least the minimum recommended treatment for depression. To improve the prediction of underutilization, patient factors associated with treatment underutilization likely need to be supplemented by additional clinical information. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Optimizing Brain Health of United States Special Operations Forces

United States Special Operations Forces (SOF) personnel are frequently exposed to explosive blasts in training and combat. However, the effects of repeated blast exposure on the human brain are incompletely understood. Moreover, there is currently no diagnostic test to detect repeated blast brain injury (rBBI). In this "Human Performance Optimization" article, we discuss how the development and implementation of a reliable diagnostic test for rBBI has the potential to promote SOF brain health, combat readiness, and quality of life.

Symptom clustering of major depression in a national telehealth sample

BACKGROUND

Major depressive disorder (MDD) is a heterogeneous disorder whose possible symptom combinations have not been well delineated. The aim of this study was to explore the heterogeneity of symptoms experienced by those with MDD to characterize phenotypic presentations.

METHODS

Cross-sectional data (N = 10,158) from a large telemental health platform were used to identify subtypes of MDD. Symptom data, gathered from both clinically-validated surveys and intake questions, were analyzed via polychoric correlations, principal component analysis, and cluster analysis.

RESULTS

Principal components analysis (PCA) of baseline symptom data revealed 5 components, including anxious distress, core emotional, agitation/irritability, insomnia, and anergic/apathy components. PCA-based cluster analysis resulted in four MDD phenotypes, the largest of which was characterized by a prominent elevation on the anergic/apathy component, but also core emotional. The four clusters differed on demographic and clinical characteristics.

LIMITATIONS

The primary limitation of this study is that the phenotypes uncovered are limited by the questions asked. These phenotypes will need to be cross validated with other samples, potentially expanded to include biological/genetic variables, and followed longitudinally.

CONCLUSIONS

The heterogeneity in MDD, as illustrated by the phenotypes in this sample, may explain the heterogeneity of treatment response in large-scale treatment trials. These phenotypes can be used to study varying rates of recovery following treatment and to develop clinical decision support tools and artificial intelligence algorithms. Strengths of this study include its size, breadth of included symptoms, and novel use of a telehealth platform.

Can mild traumatic brain injury alter cognition chronically? A LIMBIC-CENC multicenter study

OBJECTIVE

While outcome from mild traumatic brain injury (mTBI) is generally favorable, concern remains over potential negative long-term effects, including impaired cognition. This study examined the link between cognitive performance and remote mTBIs within the Long-term Impact of Military-relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium (LIMBIC-CENC) multicenter, observational study of Veterans and service members (SMs) with combat exposure.

METHOD

Baseline data of the participants passing all cognitive performance validity tests (n = 1,310) were used to conduct a cross-sectional analysis. Using multivariable regression models that adjusted for covariates, including age and estimated preexposure intellectual function, positive mTBI history groups, 1-2 lifetime mTBIs (nonrepetitive, n = 614), and 3 + lifetime mTBIs (repetitive; n = 440) were compared to TBI negative controls (n = 256) on each of the seven cognitive domains computed by averaging Z scores of prespecified component tests. Significance levels were adjusted for multiple comparisons.

RESULTS

Neither of the mTBI positive groups differed from the mTBI negative control group on any of the cognitive domains in multivariable analyses. Findings were also consistently negative across sensitivity analyses (e.g., mTBIs as a continuous variable, number of blast-related mTBIs, or years since the first and last mTBI).

CONCLUSIONS

Our findings demonstrate that the average veteran or SM who experienced one or more mTBIs does not have postacute objective cognitive deficits due to mTBIs alone. A holistic health care approach including comorbidity assessment is indicated for patients reporting chronic cognitive difficulties after mTBI(s), and strategies for addressing misattribution may be beneficial. Future study is recommended with longitudinal designs to assess within-subjects decline from potential neurodegeneration. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Comparing Outcomes of the Veterans Health Administration's Traumatic Brain Injury and Mental Health Screening Programs: Types and Frequency of Specialty Services Used

The Veterans Health Administration (VHA) screens veterans who deployed in support of the wars in Afghanistan and Iraq for traumatic brain injury (TBI) and mental health (MH) disorders. Chronic symptoms after mild TBI overlap with MH symptoms, for which there are already established screens within the VHA. It is unclear whether the TBI screen facilitates treatment for appropriate specialty care over and beyond the MH screens. Our primary objective was to determine whether TBI screening is associated with different types (MH, Physical Medicine & Rehabilitation [PM&R], and Neurology) and frequency of specialty services compared with the MH screens. A retrospective cohort design examined veterans receiving VHA care who were screened for both TBI and MH disorders between Fiscal Year (FY) 2007 and FY 2018 (N = 241,136). We calculated service utilization counts in MH, PM&R, and Neurology in the six months after the screens. Zero-inflated negative binomial regression models of encounters (counts) were fit separately by specialty care type and for a total count of specialty services. We found that screening positive for TBI resulted in 2.38 times more specialty service encounters than screening negative for TBI. Compared with screening positive for MH only, screening positive for both MH and TBI resulted in 1.78 times more specialty service encounters and 1.33 times more MH encounters. The TBI screen appears to increase use of MH, PM&R, and Neurology services for veterans with post-deployment health concerns, even in those also identified as having a possible MH disorder.

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.

Automated neuropsychological assessment metrics (v4) military expanded battery: Normative data for special operations forces

Objective: The Automated Neuropsychological Assessment Metrics (ANAM) has long been used to assess cognition in military samples before deployment and following injury. The purpose of this study was to explore the effects of various demographic factors on the ANAM4 Military Expanded (ANAM4 ME) performance of Special Operations Forces (SOF) and to provide regression-based normative data for clinicians working with SOF personnel. Method: The sample was a large active duty military sample of SOF and support personnel (n = 24,072) who were tested under a new baseline policy. Results: Performance differences based on demographic variables were generally small. In general, increasing age was associated with significantly worse performance, except on mathematical processing. Higher education level was associated with better performance on most subtests, as expected, but was associated with worse performance on spatial processing. Conclusion: This paper provides regression formulas for calculating adjusted scores based on the most relevant demographic variables, as well as base rates of obtaining one or more clearly above or below average scores across the entire ANAM4 ME battery.

Telehealth-Supported Decision-making Psychiatric Care for Suicidal Ideation: Longitudinal Observational Study

Background

Suicide is a leading cause of death in the United States, and suicidal ideation (SI) is a significant precursor and risk factor for suicide.

Objective

This study aimed to examine the impact of a telepsychiatric care platform on changes in SI over time and remission, as well as to investigate the relationship between various demographic and medical factors on SI and SI remission.

Methods

Participants included 8581 US-based adults (8366 in the treatment group and 215 in the control group) seeking treatment for depression, anxiety, or both. The treatment group included patients who had completed at least 12 weeks of treatment and had received a prescription for at least one psychiatric medication during the study period. Providers prescribed psychiatric medications for each patient during their first session and received regular data on participants. They also received decision support at treatment onset via the digital platform, which leveraged an empirically derived proprietary precision-prescribing algorithm to give providers real-time care guidelines. Participants in the control group consisted of individuals who completed the initial enrollment data and completed surveys at baseline and 12 weeks but did not receive care.

Results

Greater feelings of hopelessness, anhedonia, and feeling bad about oneself were most significantly correlated (r=0.24-0.37) with SI at baseline. Sleep issues and feeling tired or having low energy, although significant, had lower correlations with SI (r=0.13-0.14). In terms of demographic variables, advancing age and education were associated with less SI at baseline (r=−0.16) and 12 weeks (r=−0.10) but less improvement over time (r=−0.12 and −0.11, respectively). Although not different at baseline, the SI expression was evident in 34.4% (74/215) of the participants in the control group and 12.32% (1031/8366) of the participants in the treatment group at 12 weeks. Although the participants in the treatment group improved over time regardless of various demographic variables, participants in the control group with less education worsened over time, after controlling for age and depression severity. A model incorporating the treatment group, age, sex, and 8-item Patient Health Questionnaire scores was 77% accurate in its classification of complete remission. Those in the treatment group were 4.3 times more likely (odds ratio 4.31, 95% CI 2.88-6.44) to have complete SI remission than those in the control group. Female participants and those with advanced education beyond high school were approximately 1.4 times more likely (odds ratio 1.38, 95% CI 1.18-1.62) to remit than their counterparts.

Conclusions

The results highlight the efficacy of an antidepressant intervention in reducing SI, in this case administered via a telehealth platform and with decision support, as well as the importance of considering covariates, or subpopulations, when considering SI. Further research and refinement, ideally via randomized controlled trials, are needed.

Feasibility and acceptability of a novel telepsychiatry-delivered precision prescribing intervention for anxiety and depression

BACKGROUND

Major Depressive Disorder and Generalized Anxiety Disorder are pervasive and debilitating conditions, though treatment is often inaccessible and based on trial-and-error prescribing methods. The present observational study seeks to describe the use of a proprietary precision prescribing algorithm piloted during routine clinical practice as part of Brightside's telepsychiatry services. The primary aim is to determine the feasibility and acceptability of implementing this intervention. Secondary aims include exploring remission and symptom improvement rates.

METHODS

Participants were adult patients enrolled in Brightside who completed at least 12 weeks of treatment for depression and/or anxiety and received a prescription for at least one psychiatric medication. A prescription recommendation was made by Brightside's algorithm at treatment onset and was utilized for clinical decision support. Participants received baseline screening surveys of the PHQ-9 and GAD-7, and at weeks 2,4,6,8,10 and 12. Intent-to-treat (ITT) sensitivity analyses were conducted. Feasibility of the implementation was measured by the platform's ability to enroll and engage participants in timely psychiatric care, as well as offer high touch-point treatment options. Acceptability was measured by patient responses to a 5-star satisfaction rating.

RESULTS

Brightside accessed and treated 6248 patients from October 2018 to April 2021, treating a majority of patients within 4-days of enrollment. The average plan cost was $115/month. 89% of participants utilized Brightside's core medication plan at a cost of $95/month. 13.4% of patients in the study rated Brightside's services as highly satisfactory, averaging a 4.6-star rating. Furthermore, 90% of 6248 patients experienced a MCID in PHQ-9 or GAD-7 score. Remission rates were 75% (final PHQ-9 or GAD-7 score < 10) for the study sample and 59% for the ITT sample. 69.3% of Brightside patients were treated with the medication initially prescribed at intake.

CONCLUSIONS

Results suggest that the present intervention may be feasible and acceptable within the assessed population. Exploratory analyses suggest that Brightside's course of treatment, guided by precision recommendations, improved patients' symptoms of anxiety and depression.

Health Conditions Among Special Operations Forces Versus Conventional Military Service Members: A VA TBI Model Systems Study

OBJECTIVE

To examine traumatic brain injury (TBI) characteristics and comorbid medical profiles of Special Operations Forces (SOF) Active Duty Service Member/Veterans (ADSM/Vs) and contrast them with conventional military personnel.

SETTING

The 5 Veterans Affairs (VA) Polytrauma Rehabilitation Centers.

PARTICIPANTS

A subset of participants in the VA TBI Model Systems multicenter longitudinal study with known SOF status. These included 157 participants who identified as SOF personnel (average age = 41.8 years; 96% male, 81% active duty), and 365 who identified as Conventional Forces personnel (average age = 37.4 years; 92% male, 30% active duty).

DESIGN

Retrospective analysis of prospective cohort, cross-sectional.

MAIN MEASURES

The Health Comorbidities Interview.

RESULTS

SOF personnel were more likely to have deployed to a combat zone, had more years of active duty service, and were more likely active duty at time of TBI. SOF personnel were more likely to have had mild TBI (vs moderate/severe) and their TBI caused by violent mechanism. SOF personnel had a higher number of comorbidities, with more diagnoses of chronic pain, osteoarthritis, hyperlipidemia, hip fractures, and obstructive sleep apnea.

CONCLUSION

SOF personnel are at a higher risk for multimorbidity after TBI. Current rehabilitation practices should incorporate early screening and treatment of common conditions in this population, while future practices may benefit from a focus on prevention.

Do older adults benefit from telepsychiatric care: Comparison to younger adults

BACKGROUND

Telemental health platforms may increase access to care for older adults. Historically, older adults have tended to adopt new technologies at a slower rate which creates a perception that they may not be able to benefit from them. The purpose of this study was to determine whether or not older adult patients receiving psychiatric care for depression via a telemental health platform achieve the same outcomes as younger adults.

METHOD

Participant data utilized in the current investigation were obtained from a national mental health telehealth company (i.e., Brightside) and consisted of 12,908 U.S.-based adult patients receiving psychiatric care for depression between October, 2018 and January, 2022. Propensity matching was used to create an older and younger sample (n = 141 in each) using 23 covariates. These samples were then compared using repeated measures ANOVA on Patient Health Questionnaire-9 (PHQ-9) scores at start of treatment, 6 weeks, 8 weeks, 10 weeks, 12 weeks, 14 weeks, and 16 weeks.

RESULTS

Despite matching, the groups still significantly differed on prior mental health treatment, such that more older adults reported having had prior mental health treatment. There were no other differences between the groups on assessed variables. Both younger and older adults had decreasing scores over time with no significant differences between them.

CONCLUSION

Older adults have similar improvement in depression symptom severity over time following initiation of psychiatric treatment via a telehealth platform. These findings suggest that age is not a barrier to benefitting from telepsychiatric care.

Exploring social determinants of health: Comparing lower and higher income individuals participating in telepsychiatric care for depression

BACKGROUND

Telemental health may increase access to care; there has been little research on efficacy with those at the lower end of the income distribution. The purpose of this study was to determine whether lower vs. higher income patients receiving telepsychiatric care for depression achieve: (1) effective symptom reduction and (2) similar outcomes.

METHODS

Data utilized were obtained from a national mental health telehealth company and consisted of 5,426 U.S.-based patients receiving psychiatric care for moderate to severe depression between October, 2018 and January, 2022. Propensity matching was used to create lower and higher income samples (n = 379 in each) using 22 covariates. These samples were then compared using repeated measures ANOVA on Patient Health Questionnaire-9 (PHQ-9) scores at start of treatment, 6, 8, 10, 12, 14, and 16 weeks.

RESULTS

Both lower and higher income groups made significant improvement over time, with groups averaging mild symptom severity by week 16. There was a significant group x time interaction, such that the lower income group had significantly greater depression severity at the last two timepoints.

CONCLUSION

Lower and higher income groups both made significant improvement in depression symptom severity over time following initiation of psychiatric treatment via a telehealth platform, though higher income individuals, all else being equal besides employment, tend to do better. These findings suggest that when lower income individuals do participate in care, good outcomes can be achieved. Further research is needed to better understand the role social determinants of health (SDOH) play in outcome disparities.

Neurobehavioral Symptoms in U.S. Special Operations Forces in Rehabilitation After Traumatic Brain Injury: A TBI Model Systems Study

INTRODUCTION

Special Operations Forces (SOF) personnel are at increased risk for traumatic brain injury (TBI), when compared with conventional forces (CF). Prior studies of TBI in military samples have not typically investigated SOF vs. CF as specific subgroups, despite documented differences in premorbid resilience and post-injury comorbidity burden. The aim of the current study was to compare SOF vs. CF on the presence of neurobehavioral symptoms after TBI, as well as factors influencing perception of symptom intensity.

MATERIALS AND METHODS

This study conducted an analysis of the prospective veterans affairs (VA) TBI Model Systems Cohort, which includes service members and veterans (SM/V) who received inpatient rehabilitation for TBI at one of the five VA Polytrauma Rehabilitation Centers. Of those with known SOF status (N = 342), 129 participants identified as SOF (average age = 43 years, 98% male) and 213 identified as CF (average age = 38.7 years, 91% male). SOF vs. CF were compared on demographics, injury characteristics, and psychological and behavioral health symptoms. These variables were then used to predict neurobehavioral symptom severity in univariable and multivariable analyses.

RESULTS

SOF personnel reported significantly greater posttraumatic stress disorder (PTSD) symptoms but less alcohol and drug use than the CF. SOF also reported greater neurobehavioral symptoms. When examining those with TBIs of all severities, SOF status was not associated with neurobehavioral symptom severity, while race, mechanism of TBI, and PTSD symptoms were. When examining only those with mTBI, SOF status was associated with lower neurobehavioral symptoms, while PTSD severity, white race, and certain mechanisms of injury were associated with greater neurobehavioral symptoms.

CONCLUSIONS

Among those receiving inpatient treatment for TBI, SOF SM/V reported higher neurobehavioral and symptom severity. PTSD was the strongest predictor of neurobehavioral symptoms and should be considered an important treatment target in both SOF and CF with co-morbid PTSD/TBI. A proactive human performance approach towards identification and treatment of psychological and neurobehavioral symptoms is recommended for SOF.

A Genome-wide Association Study for Concussion Risk

PURPOSE

This study aimed to screen the entire genome for genetic markers associated with risk for concussion.

METHODS

A genome-wide association analyses was performed using data from the Kaiser Permanente Research Bank and the UK Biobank. Concussion cases were identified based on electronic health records from the Kaiser Permanente Research Bank and the UK Biobank from individuals of European ancestry. Genome-wide association analyses from both cohorts were tested for concussion using a logistic regression model adjusting for sex, height, weight, and race/ethnicity using allele counts for single nucleotide polymorphisms. Previously identified genes within the literature were also tested for association with concussion.

RESULTS

There were a total of 4064 cases of concussion and 291,472 controls within the databases, with two single nucleotide polymorphisms demonstrating a genome-wide significant association with concussion. The first polymorphism, rs144663795 (P = 9.7 × 10-11; OR = 2.91 per allele copy), is located within the intron of SPATA5. Strong, deleterious mutations in SPATA5 cause intellectual disability, hearing loss, and vision loss. The second polymorphism, rs117985931 (P = 3.97 × 10-9; OR = 3.59 per allele copy), is located within PLXNA4. PLXNA4 plays a key role is axon outgrowth during neural development, and DNA variants in PLXNA4 are associated with risk for Alzheimer's disease. Previous investigations have identified five candidate genes that may be associated with concussion, but none showed a significant association in the current model (P < 0.05).

CONCLUSION

Two genetic markers were identified as potential risk factors for concussion and deserve further validation and investigation of molecular mechanisms.

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.

Obstructive Sleep Apnea Risk Is Associated with Cognitive Impairment after Controlling for Mild Traumatic Brain Injury History: A Chronic Effects of Neurotrauma Consortium Study

The contribution of sleep disturbance to persistent cognitive symptoms following a mild traumatic brain injury (mTBI) remains unclear. Obstructive sleep apnea (OSA) is very common, yet its relationship between risk factors for developing OSA and cognitive performance in those with history of mTBI has not been investigated. The current study examined OSA risk levels and its association with cognitive performance in 391 combat-exposed, post-911 veterans and service members (median age = 37 years) enrolled in the Chronic Effects of Neurotrauma Consortium (CENC) prospective multi-center study. Participants included those with and without mTBI (n = 326 and 65, respectively). When using clinical cut-offs, those with history of mTBI were more likely to be categorized as high risk for OSA (mTBI positive = 65% vs. mTBI negative = 51%). After adjustment for TBI status and demographic variables, increased OSA risk was significantly associated with worse performance on measures of complex processing speed and executive functioning (Wechsler Adult Intelligence Scale Fourth Edition Coding, Trail Making Test, part B) and greater symptom burden (Neurobehavioral Symptom Inventory). Thus, OSA, a modifiable behavioral health factor, likely contributes to cognitive performance following mTBI. Accordingly, OSA serves as a potential point of intervention to improve clinical and cognitive outcomes after injury.

Introduction to a special issue on military neuropsychology: Serving those who serve

OBJECTIVE

The military has a long history with neuropsychology and its precursors. From developing intelligence tests during World War I, to developing early capacity and personality assessments during World War II, to forward deploying for the evaluation and treatment of frequent concussive brain injuries during more recent conflicts, clinical neuropsychology has been at the forefront of military selection, healthcare and research. The objective of this special issue is to provide an overview of the latest clinical research relevant to military neuropsychology-some contributors address assessment and treatment issues that are relevant to current practice and others foretell the future of our field.

METHOD

We solicited papers from established researchers and issued a general call for papers for the special issue on military neuropsychology. Results: We received submissions from several authors, eleven of which are included in this issue. These submissions cover assessment and treatment issues, as well as healthcare utilization and return to duty issues. Two apparent themes are the importance of assessing, treating, and attending to comorbidities following traumatic brain injury (TBI) and future assessment techniques moving beyond traditional cognitive performance assessment.

CONCLUSIONS

The issue highlights the importance of research in clinical neuropsychology to the practice and advancement of military neuropsychology.

Low-Level Blast Exposure in Humans A Systematic Review of Acute and Chronic Effects

There is growing concern that military breaching and training and firing artillery and mortars, grenades, and shoulder-fired weapons may have some type of cumulative deleterious effects. There are anecdotal reports of those with repetitive exposure to low-level blast complaining of various symptoms, as well as increasing empirical evidence. The purpose of this report is to provide a systematic review of the literature on repetitive lowlevel blast as it pertains to military and police training protocols. An extensive literature search was conducted, resulting in detailed review of 18 studies. Results suggest few consistent findings, likely due to the heterogeneity of methods, high risk of bias, and lack of reliance on objective blast-exposure data. Adverse effects, when present, dissipated over time. All studies that used blast gauges found significant associations, though only a subset actually reported using the blast-gauge data (to correlate objective exposure with outcomes). When comparing studies within an outcome domain (e.g., cognitive), findings were largely inconsistent. Research with larger sample sizes, followed longitudinally, is needed.

Action Ethnography of Community Reintegration for Veterans and Military Service Members With Traumatic Brain Injury: Protocol for a Mixed Methods Study

BACKGROUND

Numerous studies of community reintegration (CR) in traumatic brain injury (TBI) have been conducted in civilian populations, but research is limited in veteran and military service member populations. Little is known about how knowledge from civilian studies translates into veterans' experiences and needs. The US Department of Veterans Health Administration (VHA) recognizes the distinctive health care needs of post-9/11 veteran and military service members, particularly with TBI, including the need to bridge health and rehabilitation-related services from acute care and inpatient settings to veteran and military service members' homes and communities to facilitate CR.

OBJECTIVE

The goal of this study is to better understand the experiences of veterans with complicated mild, moderate, or severe TBI; their families; and CR workers as veterans and servicemembers transition to and sustain living in communities. This paper describes the rationale, design, and methods used to reach this goal.

METHODS

This five-year longitudinal mixed methods study uses both a community-engaged research (CEnR) approach and an ethnographic approach. The sample includes 30 veterans and service members with TBI, 13 family caregivers, 11 CR specialists, 16 key stakeholders, and 82 community events. Interviews and observations are coded and analyzed using hierarchical coding schemes and thematic analysis. Analyses include data from surveys, interviews, and participant observations. Content analysis is used to highlight the complex social context of reintegration and to triangulate quantitative data. Egocentric (personal) social network analysis is used to examine the support system a veteran or service member has in place to facilitate reintegration.

RESULTS

Study enrollment and data collection are completed. Data analyses are underway.

CONCLUSIONS

The results of this study may provide a heightened understanding of environmental factors affecting CR in complicated mild, moderate, or severe TBI. Veteran, servicemember and family voices and insights provide VHA clinicians and policy makers with an ecological view of CR that is grounded in the life experiences of veterans, military service members, and families. The results of this study provide a roadmap for designing and testing interventions to maximize CR in a variety of domains. The longitudinal ethnographic approach allows for capturing detailed experiences within the naturalistic context. CEnR allows collaborative assessment of the social context of reintegration with community members.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/14170.

Recovery from stroke: factors affecting prognosis

Objective: Stroke is commonly seen in neuropsychological practice. Individual differences, diffuse damage, and the difficulty inherent in researching stroke create challenges for the clinician trying to synthesize the latest information to educate patients and families on prognosis. The objective of this special issue is to provide an overview of the latest clinical research in stroke - the contributors address assessment and treatment issues that are relevant to practice. Method: We solicited papers from established researchers and issued a general call for papers for the special issue on stroke. Results: We received submissions from several authors, eight of which are included in this issue. These submissions cover both assessment and treatment issues and include two review articles, one on language and one on spatial neglect. Two apparent themes are the utility of early assessment/treatment and the importance of executive functioning in predicting later functioning. Conclusions: The issue highlights the need for clinical neuropsychologists to be aware of the latest research on recovery from stroke and the importance of both assessment and management strategies to reduce impact on daily life.

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.

Understanding the impact of mild traumatic brain injury on veteran service-connected disability: results from Chronic Effects of Neurotrauma Consortium

OBJECTIVES

Disability evaluation is complex. The association between mild traumatic brain injury (mTBI) history and VA service-connected disability (SCD) ratings can have implications for disability processes in the civilian population. We examined the association of VA SCD ratings with lifetime mTBI exposure in three models: any mTBI, total mTBI number, and blast-related mTBI.

METHODS

Participants were 492 Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn veterans from four US VA Medical Centers enrolled in the Chronic Effects of Neurotrauma Consortium study between January 2015 and August 2016. Analyses entailed standard covariate-adjusted linear regression models, accounting for demographic, military, and health-related confounders and covariates.

RESULTS

Unadjusted and adjusted results indicated lifetime mTBI was significantly associated with increased SCD, with the largest effect observed for blast-related mTBI. Every unit increase in mTBI was associated with an increase in 3.6 points of percent SCD. However, hazardous alcohol use was associated with lower SCD.

CONCLUSIONS

mTBI, especially blast related, is associated with higher VA SCD ratings, with each additional mTBI increasing percent SCD. The association of hazardous alcohol use with SCD should be investigated as it may impact veteran health services access and health outcomes. These findings have implications for civilian disability processes.

Unique Aspects of Traumatic Brain Injury in Military and Veteran Populations

Traumatic brain injury (TBI), in particular mild TBI (mTBI), is a relatively common injury experienced by service members across both deployed and nondeployed environments. Although many of the principles and practices used by civilian health care providers for identifying and treating this injury apply to military settings, there are unique factors that impact mTBI-related care in service members and Veterans. This article reviews several of these factors, including the epidemiology of TBI in the military/Veteran population, the influence of military culture on this condition, and identification and treatment of mTBI in the war zone.

Post-deployment Mental Health Screening: A Systematic Review of Current Evidence and Future Directions

Population-based post-deployment screening programs within the Departments of Defense and Veterans Affairs have been implemented to assess for mental health conditions and traumatic brain injury. The purpose of this paper is to systematically review the literature on post-deployment screening within this context and evaluate evidence compared to commonly accepted screening implementation criteria. Findings reflected highly variable psychometric properties of the various screens, variable treatment referral rates following screening, low to moderate treatment initiation rates following screening, and no information on treatment completion or long-term outcomes following screening. In sum, the evidence supporting population based post-deployment screening is inconclusive. Implications are discussed.

Screening for Remote History of Mild Traumatic Brain Injury in VHA: A Critical Literature Review

OBJECTIVE

The authors reviewed the existing literature on the Veterans Health Administration's (VHA's) traumatic brain injury (TBI) screening and evaluation program to provide a qualitative synthesis and critical review of results focusing on the psychometric properties of the screen.

METHODS

All studies of the VHA's screening and evaluation process were reviewed, both those involving primary data collection and those relying upon VHA data. Diagnostic statistics were summarized and also recalculated on the basis of a positive screening rate of 20%, the observed rate within the VHA, and an estimated population prevalence of TBI of 15% within the Department of Veterans Affairs (VHA).

RESULTS

The TBI screen within the VHA is administered to nearly every eligible patient. The majority of clinical presentations are deemed to be due to mental health and/or a combination of mental health and TBI factors. The screen has good internal consistency, variable test-retest reliability, and questionable validity, with poor agreement between the TBI screen and criterion standards overall. Studies based on nonrepresentative samples reported high sensitivity. Assuming the VHA's TBI screening rate of 20% in a hypothetical sample, sensitivity is poor (the screen misses 30%-60% of TBI cases). However, specificity remains adequate. Studies based on samples with high rates of TBI reported much higher positive predictive values (and slightly lower negative predictive values) than those observed when a hypothetical TBI prevalence of 15% was used.

CONCLUSION

Questions remain about the validity of the TBI screen. Future research should address the utility of screening for TBI.

A Systems Science Approach to Understanding Polytrauma and Blast-Related Injury: Bayesian Network Model of Data From a Survey of the Florida National Guard

We sought to further define the epidemiology of the complex, multiple injuries collectively known as polytrauma/blast-related injury (PT/BRI). Using a systems science approach, we performed Bayesian network modeling to find the most accurate representation of the complex system of PT/BRI and identify key variables for understanding the subsequent effects of blast exposure in a sample of Florida National Guard members (1,443 deployed to Operation Enduring Freedom/Operation Iraqi Freedom and 1,655 not deployed) who completed an online survey during the period from 2009 to 2010. We found that postdeployment symptoms reported as present at the time of the survey were largely independent of deployment per se. Blast exposure, not mild traumatic brain injury (TBI), acted as the primary military deployment-related driver of PT/BRI symptoms. Blast exposure was indirectly linked to mild TBI via other deployment-related traumas and was a significant risk for a high level of posttraumatic stress disorder (PTSD) arousal symptoms. PTSD arousal symptoms and tinnitus were directly dependent upon blast exposure, with both acting as bridge symptoms to other postdeployment mental health and physical symptoms, respectively. Neurobehavioral or postconcussion-like symptoms had no significant dependence relationship with mild TBI, but they were synergistic with blast exposure in influencing PTSD arousal symptoms. A replication of this analysis using a larger PT/BRI database is warranted.

Web-based psychoeducational intervention for postconcussion symptoms: a randomized trial

The objective of this study was to investigate the effectiveness of a web-based educational intervention for reducing postconcussion symptoms. 158 participants with self-reported symptomatic mild traumatic brain injury were randomized to intervention versus control. There was no effect of intervention on symptom severity or attributions. Subgroup analyses suggested benefit of the web-based intervention in those receiving concurrent mental health treatment and in those participants with the greatest time since injury (>1 year after mild traumatic brain injury). Web-based educational intervention was not effective overall in this sample. However, there is some suggestion of promise in those receiving concurrent mental health treatment and with more chronic symptoms. Findings also suggest potential benefit of interventions targeting self-efficacy.

[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.

Suicidal Ideation among Florida National Guard Members: Combat Deployment and Non-Deployment Risk and Protective Factors

This study examined relationships among risk/protective factors and suicidal ideation (SI) in deployed and non-deployed National Guard members, particularly examining for possible differential effects of deployment on SI. A total of 3,098 Florida National Guard members completed an anonymous online survey that assessed variables associated with SI including demographics, current psychiatric diagnoses, and pre-, during, and post-deployment experiences. Those deployed had significantly higher rates of SI (5.5%) than those not deployed (3.0%; p < .001). In multivariate analyses, among those not deployed, SI was significantly associated with major depressive disorder (p < .001), posttraumatic stress disorder (PTSD) (p < .001), prior psychological trauma (p < .01), and heavy/hazardous alcohol consumption (p < .05). In contrast, in the deployed, only PTSD (p < .001) and deployment-related mild traumatic brain injury (p < .05) were independently associated with SI. Risk and protective factors differed by deployment status in National Guard members suggesting the possible need for cohort-specific treatment targets to minimize SI.