Elevated Serum Tau and UCHL-1 Concentrations Within 12 Months of Injury Predict Neurobehavioral Functioning 2 or More Years Following Traumatic Brain Injury: A Longitudinal Study.

OBJECTIVE: Blood-based biomarkers have received considerable attention for their diagnostic and prognostic value in the acute and postacute period following traumatic brain injury (TBI). The purpose of this study was to examine whether blood-based biomarker concentrations within the first 12 months of TBI can predict neurobehavioral outcome in the chronic phase of the recovery trajectory. SETTING: Inpatient and outpatient wards from 3 military medical treatment facilities. PARTICIPANTS: A total of 161 service members and veterans classified into 3 groups: (a) uncomplicated mild TBI (MTBI; n = 37), (b) complicated mild, moderate, severe, penetrating TBI combined (STBI; n = 46), and (c) controls (CTRL; n = 78). DESIGN: Prospective longitudinal. MAIN MEASURES: Participants completed 6 scales from the Traumatic Brain Injury Quality of Life (ie, Anger, Anxiety, Depression, Fatigue, Headaches, and Cognitive Concerns) within 12 months (baseline) and at 2 or more years (follow-up) post-injury. Serum concentrations of tau, neurofilament light, glial fibrillary acidic protein, and UCHL-1 at baseline were measured using SIMOA. RESULTS: Baseline tau was associated with worse anger, anxiety, and depression in the STBI group at follow-up (R2 = 0.101-0.127), and worse anxiety in the MTBI group (R2 = 0.210). Baseline ubiquitin carboxyl-terminal hydrolase L1 (UCHL-1) was associated with worse anxiety and depression at follow-up in both the MTBI and STBI groups (R2Δ = 0.143-0.207), and worse cognitive concerns in the MTBI group (R2Δ = 0.223). CONCLUSIONS: A blood-based panel including these biomarkers could be a useful tool for identifying individuals at risk of poor outcome following TBI.

Discriminating Mild Traumatic Brain Injury and Posttraumatic Stress Disorder Using Latent Neuroimaging and Neuropsychological Profiles in Active-Duty Military Service Members.

OBJECTIVE: Mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) commonly occur among military Service Members and Veterans and have heterogenous, but also overlapping symptom presentations, which often complicate the diagnoses of underlying impairments and development of effective treatment plans. Thus, we sought to examine whether the combination of whole brain gray matter (GM) and white matter (WM) structural measures with neuropsychological performance can aid in the classification of military personnel with mTBI and PTSD. METHODS: Active-Duty US Service Members ( n = 156; 87.8% male) with a history of mTBI, PTSD, combined mTBI+PTSD, or orthopedic injury completed a neuropsychological battery and T1- and diffusion-weighted structural neuroimaging. Cortical, subcortical, ventricular, and WM volumes and whole brain fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) were calculated. Latent profile analyses were performed to determine how the GM and WM indicators, together with neuropsychological indicators, classified individuals. RESULTS: For both GM and WM, respectively, a 4-profile model was the best fit. The GM model identified greater ventricular volumes in Service Members with cognitive symptoms, including those with a diagnosis of mTBI, either alone or with PTSD. The WM model identified reduced FA and elevated RD in those with psychological symptoms, including those with PTSD or mTBI and comorbid PTSD. However, contrary to expectation, a global neural signature unique to those with comorbid mTBI and PTSD was not identified. CONCLUSIONS: The findings demonstrate that neuropsychological performance alone is more robust in differentiating Active-Duty Service Members with mTBI and PTSD, whereas global neuroimaging measures do not reliably differentiate between these groups.

Risk factors for the presence and persistence of posttraumatic stress symptoms following traumatic brain injury in U.S. service members and veterans.

This study aimed to identify risk factors predictive of the presence and persistence of posttraumatic stress disorder (PTSD) symptom reporting following traumatic brain injury (TBI). Participants were 1,301 U.S. service members and veterans (SMVs) divided into four groups: uncomplicated mild TBI (mTBI; n = 543); complicated mild, moderate, severe, and penetrating TBI (n = 230); injured controls (n = 340); and noninjured controls (n = 188). We examined 25 factors related to demographic, injury-related, military-specific, treatment/health care need, and mental health/social support variables. Seven factors were statistically associated with the presence of DSM-IV-TR symptom criteria for PTSD: premorbid IQ, combat exposure, depression, social participation, history of mTBI, need for managing mood and stress, and need for improving memory and attention, p < .001 (51.3% variance). When comparing the prevalence of these risk factors in a longitudinal cohort (n = 742) across four PTSD trajectory groups (i.e., asymptomatic, improved, developed, persistent), a higher proportion of participants in the persistent PTSD group reported worse depression, a lack of social participation, and history of mTBI. Additionally, a higher proportion of participants in the persistent and developed PTSD groups reported the need for managing mood/stress and improving memory/attention. When considered simultaneously, the presence of ≥ 1 or ≥ 2 risk factors was associated with a higher proportion of participants in the developed and persistent PTSD groups, ps < .001. These risk factors may be useful in identifying SMVs at risk for the development and/or persistence of PTSD symptoms who may need intervention.

Research Letter: Long-Term Outcomes Following Cognitive Rehabilitation for Mild Traumatic Brain Injury: A 5-Year Follow-Up of a Cohort From the SCORE Randomized Clinical Trial.

OBJECTIVE: To examine the functioning of military service members 5 years after completing a randomized controlled trial (RCT) of cognitive rehabilitation for mild traumatic brain injury (mTBI). SETTING: Home-based telephonic interview and internet-based self-ratings. PARTICIPANTS: Sixty-nine of the 126 (55%) active-duty service members who were enrolled in a 4-arm RCT of cognitive rehabilitation 3 to 24 months after mTBI and were successfully contacted by phone 5 years later. Original and 5-year follow-up participants in each of 4 RCT treatment arms included: psychoeducation ( n = 32 original, n = 17 follow-up), computer ( n = 30 original, n = 11 follow-up), therapist-directed ( n = 30 original, n = 23 follow-up), integrated ( n = 34 original, n = 18 follow-up). DESIGN: Inception cohort evaluated 5 years after completion of an RCT of cognitive rehabilitation. MAIN MEASURES: Postconcussion symptoms (Neurobehavioral Symptom Inventory total score), psychological distress (Symptom Checklist-90-revised Global Severity Index score), and functional cognitive/behavioral symptoms (Key Behaviors Change Inventory total average score). RESULTS: Participants' postconcussive symptoms and psychological distress improved at the 5-year follow-up. Functional cognitive/behavioral symptoms were not significantly improved, but therapeutic gains were maintained across time, to 5 years after completing the RCT. CONCLUSION: In this sample of military personnel, postconcussive symptoms and psychological distress significantly improved from posttreatment to 5 years after cognitive rehabilitation, regardless of treatment arm. Functional cognitive/behavioral symptoms significantly improved with treatment while treatment gains were maintained at the 5-year follow-up. Replication of these results with a larger sample and interim data between 18 weeks and 5 years post-treatment is needed.

Latent Neuropsychological Profiles to Discriminate Mild Traumatic Brain Injury and Posttraumatic Stress Disorder in Active-Duty Service Members.

OBJECTIVE: To determine whether cognitive and psychological symptom profiles differentiate clinical diagnostic classifications (eg, history of mild traumatic brain injury [mTBI] and posttraumatic stress disorder [PTSD]) in military personnel. METHODS: US Active-Duty Service Members ( N = 209, 89% male) with a history of mTBI ( n = 56), current PTSD ( n = 23), combined mTBI + PTSD ( n = 70), or orthopedic injury controls ( n = 60) completed a neuropsychological battery assessing cognitive and psychological functioning. Latent profile analysis was performed to determine how neuropsychological outcomes of individuals clustered together. Diagnostic classifications (ie, mTBI, PTSD, mTBI + PTSD, and orthopedic injury controls) within each symptom profile were examined. RESULTS: A 5-profile model had the best fit. The profiles differentiated subgroups with high (34.0%) or normal (21.5%) cognitive and psychological functioning, cognitive symptoms (19.1%), psychological symptoms (15.3%), and combined cognitive and psychological symptoms (10.0%). The symptom profiles differentiated participants as would generally be expected. Participants with PTSD were mainly represented in the psychological symptom subgroup, while orthopedic injury controls were mainly represented in the high-functioning subgroup. Further, approximately 79% of participants with comorbid mTBI and PTSD were represented in a symptomatic group (∼24% = cognitive symptoms, ∼29% = psychological symptoms, and 26% = combined cognitive/psychological symptoms). Our results also showed that approximately 70% of military personnel with a history of mTBI were represented in the high- and normal-functioning groups. CONCLUSIONS: These results demonstrate both overlapping and heterogeneous symptom and performance profiles in military personnel with a history of mTBI, PTSD, and/or mTBI + PTSD. The overlapping profiles may underscore why these diagnoses are often difficult to diagnose and treat, but suggest that advanced statistical models may aid in identifying profiles representing symptom and cognitive performance impairments within patient groups and enable identification of more effective treatment targets.

The impact of prior head injury on outcomes following group and individual cognitive processing therapy among military personnel.

This study examined the impact of a history of head injury (HHI) on posttraumatic stress disorder (PTSD) and depression symptoms in active duty military personnel following group and individual cognitive processing therapy (CPT). Data for these secondary analyses were drawn from a clinical trial comparing group and individual CPT. Service members (N = 268, 91.0% male) were randomized to 12 sessions of group (n = 133) or individual (n = 135) CPT. Most participants (57.1%) endorsed a deployment-related HHI, 92.8% of whom reported currently experiencing symptoms (CES) related to the head injury (i.e., HHI/CES). Patients classified as non-HHI/CES demonstrated large, significant improvements in PTSD symptom severity in both individual and group therapy, ds = 1.1, p < .001. Patients with HHI/CES status showed similar significant improvements when randomized to individual CPT, d = 1.4, p < .001, but did not demonstrate significant improvements when randomized to group CPT, d = 0.4, p = .060. For participants classified as HHI/CES, individual CPT was significantly superior to group CPT, d = 0.98, p = .003. Symptoms of depression improved following treatment, with no significant differences by treatment delivery format or HHI/CES status. The findings of this clinical trial subgroup study demonstrate evidence that group CPT is less effective than individual CPT for service members classified as HHI/CES. The results suggest that HHI/CES status may be important to consider in selecting patients for group or individual CPT; additional research is needed to confirm the clinical implications of these findings.

Intracranial Abnormalities Are Associated With Fewer Self-Reported Symptoms in Military Service Members Following Moderate-to-Severe Traumatic Brain Injury.

OBJECTIVE: This study examined the relationship between intracranial abnormalities (ICAs) and self-reported neurobehavioral and posttraumatic stress (PTS) symptoms in members of the military with moderate-to-severe traumatic brain injury (msTBI). METHOD: Participants included 539 members of the US military with nonpenetrating msTBI. Self-reported neurobehavioral and PTS symptoms were assessed using the Neurobehavioral Symptom Inventory and the PTSD Checklist-Civilian Version. ICAs were categorized as present/absent (by subtype) based upon medical record review. Spearman rank-order correlations and stepwise multiple regression analyses examined univariate and combined predictive relationships between ICAs and self-reported symptoms. RESULTS: The presence of any ICA was associated with reduced self-reported neurobehavioral and PTS symptoms. ICA-associated reductions were largest for PTS, followed by affective and cognitive neurobehavioral symptoms, and relatively weak for somatic/sensory and vestibular symptoms. Effects of different types of ICAs were comparable. Greater time since injury was related to greater symptom report, whereas duration of loss of consciousness and posttraumatic amnesia were not consistently related to self-reported symptoms. CONCLUSIONS: Results suggest that ICAs are associated with suppression of reported PTS and neurobehavioral symptoms-potentially via reduction in self-awareness. These findings support comprehensive, objective evaluation to identify impairments in self-awareness and functioning in msTBI patients.

Role of deployment-related mTBI and resilience in perceived participation limitations among Veterans.

Problems with social functioning are common following combat deployment, and these may be greater among individuals with a history of traumatic brain injury (TBI). The present investigation examined the impact of mild TBI (mTBI), deployment-related characteristics, and resilience on perceived participation limitations among combat Veterans. This was a cross-sectional study of 143 participants with a history of at least one deployment-related mTBI (TBI group) and 80 without a history of lifetime TBI (Comparison group). Self-report measures of participation, resilience, posttraumatic stress disorder (PTSD) symptoms, and combat exposure were administered. In addition, each participant completed a structured interview to assess lifetime TBI history. The groups did not differ in basic demographics, but significant differences were found for perceived limitations in participation, the presence of PTSD symptoms, and intensity of combat exposure. A stepwise model indicated a significant effect of resilience on reported limitations in participation (adjusted R2 = 0.61). Individuals with higher resiliency reported a higher degree of social participation, and this effect was stronger in the TBI group. Deployment-related characteristics, including intensity of combat exposure, did not have a significant effect (adjusted R2 = 0.28) on social participation. The role of resilience should be recognized within post-deployment transition and rehabilitation programs.

Patient Attribution of Posttraumatic Symptoms to Brain Injury Versus PTSD in Military-Related Mild TBI.

OBJECTIVE: Persistent cognitive, somatic, and neuropsychiatric symptoms following mild traumatic brain injury (TBI) are influenced by posttraumatic stress disorder (PTSD), particularly in military patients. The authors evaluated the degree to which military service members with a history of mild TBI attributed posttraumatic symptoms to TBI versus PTSD. METHODS: Service members (N=372) with mild TBI were surveyed about the severity of posttraumatic symptoms across four symptom clusters (cognitive, affective, somatosensory, and vestibular) with the Neurobehavioral Symptom Inventory (NSI). Participants rated the degree to which they believed TBI, PTSD, or other conditions contributed to their symptoms. Differences in cognitive, affective, somatosensory, and vestibular symptom severity were evaluated across participants with TBI, PTSD, or combined TBI-PTSD attribution. Logistic regression was used to evaluate the association between symptom profiles and attribution. RESULTS: Participants attributed symptoms mostly to TBI, followed by insufficient sleep, PTSD, chronic pain, depression, and deployment-readjustment stress. PTSD and combined TBI-PTSD attribution were associated with higher total NSI scores (39.5 and 51.6, respectively), compared with TBI attribution only (31.4) (F=29.08, df=3, 358, p<0.01), as well as higher scores in every symptom category. More severe affective symptoms were associated with decreased odds of TBI attribution (odds ratio=0.90, 95% CI=0.83-0.97) and increased odds of PTSD attribution (odds ratio=1.14, 95% CI=1.03-1.26). A PTSD diagnosis was highly associated with PTSD attribution (odds ratio=2.44, 95% CI=1.07-5.58). CONCLUSIONS: The nature and severity of posttraumatic symptoms appear to play a role in patient beliefs about the causes of symptoms, whether from TBI or PTSD.

Differences in Posttraumatic Stress Disorder, Depression, and Attribution of Symptoms in Service Members With Combat Versus Noncombat Mild Traumatic Brain Injury.

OBJECTIVE: This study compares combat-related mild traumatic brain injury (mTBI) to non-combat-related mTBI in rates of posttraumatic stress disorder (PTSD) and depression after injury, severity of postconcussive symptoms (PCSs), and attribution of those symptoms to mTBI versus PTSD. PARTICIPANTS: A total of 371 active duty service members (SMs) with documented history of mTBI, divided into combat and non-combat-related cohorts. DESIGN: Retrospective cohort study. MAIN MEASURES: Diagnoses of PTSD and depression based on medical record review and self-report. PCSs measured using Neurobehavioral Symptom Index. Attribution of symptoms based on a rating scale asking how much mTBI, PTSD, depression, deployment, or readjustment stress contributed to current symptoms. RESULTS: Prevalence of PTSD was significantly higher after a combat-related mTBI, compared with a noncombat mTBI (P = .001). Prevalence of depression did not differ between the 2 groups. PCSs were high in both combat and noncombat mTBIs, with no statistical difference between groups. SMs with PTSD reported higher PCS, regardless of combat status. SMs without PTSD attributed symptoms mainly to mTBI, whereas SMs with PTSD, regardless of combat status, were much more likely to attribute symptoms to PTSD, depression, and deployment/readjustment stress. CONCLUSIONS: This research contributes to our understanding of the complex interplay between mTBI and PTSD in both combat and noncombat injuries within the military population and the importance of addressing both simultaneously.

Self-efficacy predicts response to cognitive rehabilitation in military service members with post-concussive symptoms.

This study examined whether self-efficacy differentiated treatment responders from non-responders in a trial of cognitive rehabilitation (CR) for postconcussive symptoms. 126 service members with mild TBI seen on average 9.5 months since injury completed one of four cognitive rehabilitation treatments for 6 weeks. The four treatment arms were: (1) Psychoeducation control, (2) Self-administered computerized CR, (3) Interdisciplinary CR, and (4) Interdisciplinary CR integrated with CBT. Outcome was assessed across time (baseline, and 6, 12, and 18 weeks post-treatment) for three domains: psychological (Symptom Checklist-90-Revised; SCL-90-R), cognitive (Paced Auditory Serial Addition Test; PASAT), and functional/behavioural (Key Behaviors Change Inventory; KBCI). Mixed model ANOVAs tested for self-efficacy differences across time in treatment responders versus non-responders, as defined by reliable change indices. A significant interaction was found on the SCL-90 such that responders had increasing self-efficacy with respect to psychological symptoms across four time points, whereas non-responders' self-efficacy did not change. Perceived self-efficacy at the beginning of treatment was associated with treatment engagement within the psychological domain for responders only, suggesting a mediating role in treatment outcome. Overall, results suggest that increasing patients' level of self-efficacy may be important for successful treatment of psychological distress in those with remote concussion.

Postconcussion Symptom Reporting After Mild Traumatic Brain Injury in Female Service Members: Impact of Gender, Posttraumatic Stress Disorder, Severity of Injury, and Associated Bodily Injuries.

OBJECTIVE: Examine effects of diagnostically relevant posttraumatic stress disorder (PTSD) symptoms, mild traumatic brain injury (TBI) severity, and associated bodily injury severity on postconcussion symptom reporting in female service members (SM) compared with a matched sample of male SM. SETTING: Six US military medical treatment facilities. PARTICIPANTS: A total of 158 SM (79 females, 79 males) evaluated within 30 months after mild TBI. Men and women were matched by age, days postinjury, PTSD symptom status, mild TBI severity, and bodily injury severity. All passed a measure of symptom validity. DESIGN: Compare reported postconcussion symptoms for men and women stratified by PTSD diagnostic symptoms (present/absent), mild TBI severity (alteration of consciousness/loss of consciousness), and bodily injury severity (mild/moderate-severe). MAIN MEASURES: Neurobehavioral Symptom Inventory, PTSD Checklist, Abbreviated Injury Scale. RESULTS: Overall postconcussion symptom reporting increased with PTSD but did not significantly differ based on severity of mild TBI or associated bodily injury. Females reported more somatosensory and/or vestibular symptoms than males under some circumstances. Females in the PTSD-Present group, Alteration of Consciousness Only group, and Moderate-Severe Bodily Injury group reported more somatosensory symptoms than males in those groups. Females in the Alteration of Consciousness Only group and Minor Bodily Injury group reported more vestibular symptoms than males in those groups. CONCLUSION: Diagnostically relevant PTSD symptoms, mild TBI severity, and bodily injury severity differentially impact somatosensory and vestibular postconcussion symptom reporting for male and female SM after mild TBI. Controlling for PTSD and symptom validity resulted in fewer gender-based differences in postconcussive symptoms than previously demonstrated in the literature.

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.

OBJECTIVE: To examine differences in objective neurocognitive performance and subjective cognitive symptoms in individuals with a history of a single concussion, multiple concussions, orthopedic injuries, and posttraumatic stress disorder (PTSD). METHOD: Participants included 116 military service members who sustained a mild traumatic brain injury (mTBI) during combat deployment. Subjects were subdivided into groups based on concussion frequency: a single concussion (n = 42), 2 concussions (n = 21), and 3 or more concussions (n = 53). Eighty-one subjects sustained an orthopedic injury (n = 60) during deployment or were diagnosed with PTSD (n = 21), but had no history of mTBI. Subjects completed a battery of neuropsychological tests and self-report measures of postconcussive symptoms, PTSD symptoms, and psychopathology. RESULTS: No differences were found among the concussion groups on a composite neuropsychological measure. The PTSD group had the highest number of symptom complaints, with the 2-concussion and 3-plus-concussion groups being most similar to the PTSD group. The concussion groups showed a nonsignificant pattern of increasing distress with increasing number of concussions. CONCLUSIONS: The current findings are consistent with meta-analytic results showing no differential effect on neuropsychological functioning due to multiple concussions. Results also support the burden of adversity hypothesis suggesting increasing symptom levels with increasing psychological or physically traumatic exposures.

Relationships Between Subcortical Shape Measures and Subjective Symptom Reporting in US Service Members With Mild Traumatic Brain Injury.

OBJECTIVE: To assess interactions of subcortical structure with subjective symptom reporting associated with mild traumatic brain injury (mTBI), using advanced shape analysis derived from volumetric MRI. PARTICIPANTS: Seventy-six cognitively symptomatic individuals with mTBI and 59 service members sustaining only orthopedic injury. DESIGN: Descriptive cross-sectional study. MAIN MEASURES: Self-report symptom measures included the PTSD Checklist-Military, Neurobehavioral Symptom Inventory, and Symptom Checklist-90-Revised. High-dimensional measures of shape characteristics were generated from volumetric MRI for 7 subcortical structures in addition to standard volume measures. RESULTS: Several significant interactions between group status and symptom measures were observed across the various shape measures. These interactions were revealed in the right thalamus and globus pallidus for each of the shape measures, indicating differences in structure thickness and expansion/contraction for these regions. No relationships with volume were observed. CONCLUSION: Results provide evidence for the sensitivity of shape measures in differentiating symptomatic mTBI individuals from controls, while volumetric measures did not exhibit this same sensitivity. Disruptions to thalamic nuclei identified here highlight the role of the thalamus in the spectrum of symptoms associated with mTBI. Additional work is needed to prospectively, and longitudinally, assess these measures along with cognitive performance and advanced multimodal imaging methods to extend the utility of shape analysis in relation to functional outcomes in this population.

Diffusion Imaging Findings in US Service Members With Mild Traumatic Brain Injury and Posttraumatic Stress Disorder.

OBJECTIVE: Use diffusion tensor imaging to investigate white matter microstructure attributable to mild TBI (mTBI) and/or posttraumatic stress disorder (PTSD). PARTICIPANTS: Twenty-seven individuals with mTBI only, 16 with PTSD only, 42 with mTBI + PTSD, and 43 service members who sustained orthopedic injury. DESIGN: Descriptive cross-sectional study. MAIN MEASURES: Clinical diffusion tensor imaging sequence to assess fractional anisotropy, mean, axial, and radial diffusivity within selected regions of interest. RESULTS: Corrected analyses revealed a pattern of lower white matter integrity in the PTSD group for several scalar metrics. Regions affected included primarily right hemisphere areas of the internal capsule. These differences associated with the PTSD only cohort were observed in relation to all 3 comparison groups, while the mTBI + PTSD group did not exhibit any notable pattern of white matter abnormalities. CONCLUSION: Results suggest that lower resolution scan sequences are sensitive to post-acute abnormalities associated with PTSD, particularly in the right hemisphere. In addition, these findings suggest that ongoing PTSD symptoms are associated with differences in white matter diffusion that are more readily detected in a clinical scan sequence than mTBI abnormalities. Future studies are needed to prospectively assess service members prior to onset of injury to verify this pattern of results.

Cognitive Rehabilitation for Military Service Members With Mild Traumatic Brain Injury: A Randomized Clinical Trial.

OBJECTIVE: To compare cognitive rehabilitation (CR) interventions for mild traumatic brain injury (mTBI) with standard of care management, including psychoeducation and medical care for noncognitive symptoms. SETTING: Military medical center. PARTICIPANTS: A total of 126 service members who received mTBI from 3 to 24 months before baseline evaluation and reported ongoing cognitive difficulties. INTERVENTIONS: Randomized clinical trial with treatment outcomes assessed at baseline, 3-week, 6-week, 12-week, and 18-week follow-ups. Participants were randomly assigned to one of four 6-week treatment arms: (1) psychoeducation, (2) computer-based CR, (3) therapist-directed manualized CR, and (4) integrated therapist-directed CR combined with cognitive-behavioral psychotherapy (CBT). Treatment dosage was constant (10 h/wk) for intervention arms 2 to 4. MEASURES: Paced Auditory Serial Addition Test (PASAT); Symptom Checklist-90 Revised (SCL-90-R); Key Behaviors Change Inventory (KBCI). RESULTS: No differences were noted between treatment arms on demographics, injury-related characteristics, or psychiatric comorbidity apart from education, with participants assigned to the computer arm having less education. Using mixed-model analysis of variance, all 4 treatment groups showed a significant improvement over time on the 3 primary outcome measures. Treatment groups showed equivalent improvement on the PASAT. The therapist-directed CR and integrated CR treatment groups had better KBCI outcomes compared with the psychoeducation group. Improvements on primary outcome measures during treatment were maintained at follow-up with no differences among arms. CONCLUSIONS: Both therapist-directed CR and integrated CR with CBT reduced functional cognitive symptoms in service members after mTBI beyond psychoeducation and medical management alone.

Profile Analysis of the Neurobehavioral and Psychiatric Symptoms Following Combat-Related Mild Traumatic Brain Injury: Identification of Subtypes.

OBJECTIVE: To explore the taxonomy of combat-related mild traumatic brain injury (mTBI) based on symptom patterns. PARTICIPANTS: Up to 1341 military personnel who experienced a combat-related mTBI within 2 years of evaluation. MEASURES: Neurobehavioral Symptom Inventory and PTSD Checklist-Civilian Version (PCL-C). RESULTS: Cluster analysis revealed the following 4 subtypes: primarily psychiatric (posttraumatic stress disorder) group, a cognitive group, a mixed symptom group, and a good recovery group. The posttraumatic stress disorder cluster (21.9% of the sample) reported symptoms related to hyperarousal and dissociation/depression with few complaints related to cognition or headaches. The cognitive group (21.5% of the sample) had primarily cognitive and headache complaints with few mood symptoms. The mixed profile cluster included 18.6% of the sample and was characterized by a combination of mood complaints (hyperarousal and dissociation/depression), cognitive complaints, and headaches. The largest cluster (37.8% of the sample) had an overall low symptom profile and was labeled the "good recovery" group. CONCLUSIONS: The results support a unique taxonomy for combat-related mTBI. The clinical differences among these subtypes indicate a need for unique treatment resources and programs.

Screening for postdeployment conditions: development and cross-validation of an embedded validity scale in the neurobehavioral symptom inventory.

OBJECTIVE: To develop and cross-validate internal validity scales for the Neurobehavioral Symptom Inventory (NSI). PARTICIPANTS: Four existing data sets were used: (1) outpatient clinical traumatic brain injury (TBI)/neurorehabilitation database from a military site (n = 403), (2) National Department of Veterans Affairs TBI evaluation database (n = 48 175), (3) Florida National Guard nonclinical TBI survey database (n = 3098), and (4) a cross-validation outpatient clinical TBI/neurorehabilitation database combined across 2 military medical centers (n = 206). RESEARCH DESIGN: Secondary analysis of existing cohort data to develop (study 1) and cross-validate (study 2) internal validity scales for the NSI. MAIN MEASURES: The NSI, Mild Brain Injury Atypical Symptoms, and Personality Assessment Inventory scores. RESULTS: Study 1: Three NSI validity scales were developed, composed of 5 unusual items (Negative Impression Management [NIM5]), 6 low-frequency items (LOW6), and the combination of 10 nonoverlapping items (Validity-10). Cut scores maximizing sensitivity and specificity on these measures were determined, using a Mild Brain Injury Atypical Symptoms score of 8 or more as the criterion for invalidity. Study 2: The same validity scale cut scores again resulted in the highest classification accuracy and optimal balance between sensitivity and specificity in the cross-validation sample, using a Personality Assessment Inventory Negative Impression Management scale with a T score of 75 or higher as the criterion for invalidity. CONCLUSIONS: The NSI is widely used in the Department of Defense and Veterans Affairs as a symptom-severity assessment following TBI, but is subject to symptom overreporting or exaggeration. This study developed embedded NSI validity scales to facilitate the detection of invalid response styles. The NSI Validity-10 scale appears to hold considerable promise for validity assessment when the NSI is used as a population-screening tool.

Symptomatic Recovery from Concussion in Military Service Members with and Without Associated Bodily Injuries.

Research has found that service members (SMs) with mild traumatic brain injury (mTBI) and co-occurring bodily injuries endorse lower chronic postconcussive symptom severity than SMs with mTBI and no bodily injuries. Investigations were conducted with primarily post-9/11 war-era SMs with blast injuries. The current study explores these findings in a cohort of more heterogeneous and recently evaluated military SM. Possible reasons suggested for the earlier findings include SMs with bodily injuries report fewer postconcussive symptoms due to (1) focusing attention on extra-cranial injuries and associated pain; (2) receiving more interpersonal and medical support, lowering distress; (3) using analgesics such as morphine or opioids; or (4) experiencing delayed postconcussive symptoms. The current investigation evaluates each of these hypothesized reasons for the earlier findings and the generalizability of the findings to a more recent sample. Data were extracted from 165 SMs in a TBI repository at a U.S. military medical center. All participants reported a history of an mTBI, confirmed by a clinical interview to meet Veterans Affairs and Department of Defense criteria. Other bodily injuries received at the time of the mTBI were documented with the Abbreviated Injury Scale (AIS). Multiple regression models evaluated the ability of the four hypothesized mechanisms to predict postconcussive symptom severity, measured by the Neurobehavioral Symptom Inventory. SMs with bodily injuries (n = 48) reported nonsignificantly lower postconcussive symptoms than SMs with no bodily injuries (n = 117). The level of subjective pain was a determinant of postconcussive symptom severity among SMs with a history of mTBI, with or without associated bodily injuries. Social support was a weaker negative predictor of postconcussive symptoms among SMs with no associated bodily injuries.

Clinical relevance of subthreshold PTSD versus full criteria PTSD following traumatic brain injury in U.S. service members and veterans.

BACKGROUND: The purpose of this cross-sectional study was to examine the influence of subthreshold posttraumatic stress disorder (PTSD) and full PTSD on quality of life following mild traumatic brain injury (mTBI). METHODS: Participants were 734 service members and veterans (SMV) classified into two injury groups: uncomplicated mild TBI (MTBI; n = 596) and injured controls (IC, n = 139). Participants completed a battery of neurobehavioral measures, 12-or-more months post-injury, that included the PTSD Checklist Civilian version, Neurobehavioral Symptom Inventory, and select scales from the TBI-QOL and MPAI. The MTBI group was divided into three PTSD subgroups: No-PTSD (n = 266), Subthreshold PTSD (n = 139), and Full-PTSD (n = 190). RESULTS: There was a linear relationship between PTSD severity and neurobehavioral functioning/quality of life in the MTBI sample. As PTSD severity increased, significantly worse scores were found on 11 of the 12 measures (i.e. , MTBI: Full-PTSD > Sub-PTSD > No-PTSD). When considering the number of clinically elevated scores, a linear relationship between PTSD severity and neurobehavioral functioning/quality of life was again observed in the MTBI sample (e.g., 3-or-more elevated scores: Full-PTSD = 92.1 %, Sub-PTSD = 61.9 %, No-PTSD = 19.9 %). LIMITATIONS: Limitations included the use of a self-report measure to determine diagnostic status that may under/overcount or mischaracterize individuals. CONCLUSION: PTSD symptoms, whether at the level of diagnosable PTSD, or falling short of that because of the intensity or characterization of symptoms, have a significant negative impact on one's quality of life following MTBI. Clinicians' treatment targets should focus on the symptoms that are most troubling for an individual and the individual's perception of quality of life, regardless of the diagnosis itself.