Clinical utility of the Neurobehavioral Symptom Inventory validity scales to screen for symptom exaggeration following traumatic brain injury

Effects of mTBI with loss of consciousness on neurobehavioral symptoms, depression, and insomnia in former collegiate and NFL football athletes

OBJECTIVE

Considering that diagnostic decisions about mTBI are often predicated on clinical symptom criteria, it is imperative to determine which initial presentation features of mTBI have prognostic significance for identifying those at high risk for long-term functional impairment.

SETTING

Zoom interview Participants: Male, former NCAA Division I, and professional-level National Football League (NFL) athletes (n = 177) between the ages of 27 and 85 (M = 54.1, SD = 14.7).

DESIGN

Cross-sectional case-control. Main Measures: History of mild TBI, history of loss of consciousness (LOC), depression symptoms, insomnia, neurobehavioral symptoms.

RESULTS

Number of mTBI exposures did not predict neurobehavioral symptoms (B = 0.21, SE = 0.18, p = 0.23), but number of mTBI + LOC events did (B = 2.27, SE = 0.64, p = <.001). Further analysis revealed that the number of mTBI + LOC events predicted neurobehavioral symptoms indirectly through both depression (B = 0.85, 95% CI = [0.27, 1.52) and insomnia (B = 0.81, 95% CI = [0.3, 1.4]). Further, the direct effect of mTBI + LOC events on neurobehavioral symptoms became non-significant when depression and insomnia were added to the model (B = 0.78, SE = 0.45, p = 0.08).

CONCLUSIONS

Findings support LOC at time of injury as an important predictor of long-term outcomes. Additionally, results suggest depression and insomnia as potential mediators in the association between mTBI + LOC and neurobehavioral symptoms. These findings provide justification for early depression and insomnia symptom monitoring following mTBI + LOC.

Disentangling subjective symptom complaints and objective cognitive performance in veterans: Impact of posttraumatic stress disorder and lifetime traumatic brain injury burden

Self-reported histories of mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) symptoms are prevalent among post-9/11 veterans. Both are associated with subjective and often overlapping symptom complaints, but variably with objective neuropsychological test performances. These outcomes are seldom explored in relation to lifetime mTBI burden. This cross-sectional study examined associations of PTSD and lifetime mTBI with subjective (persistent symptoms after concussion and cognitive complaints) and objective (performances across five cognitive domains) measures among 46 veterans. Within this sample, 20 veterans had Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) confirmed PTSD (PTSD+), whereas 26 demographically-similar participants did not meet criteria (PTSD-). The Boston Assessment of Traumatic Brain Injury-Lifetime (BAT-L) yielded total mTBI scores ranging from 0 to 8. Regressions showed PTSD was associated with increased subjective symptoms/cognitive complaints, along with reduced verbal fluency, visuospatial memory, and processing speed performances. Lifetime mTBI burden was associated with subjective symptoms, but not with objective cognitive test performance, after controlling for PTSD. No significant interactions were observed. Exploratory correlations suggested that all PTSD symptom clusters were generally associated with the subjective and objective measures. However, fewer significant associations emerged within the PTSD+/- groups separately, with each group yielding somewhat different patterns of relationships. PTSD and increasing mTBI burden are consistently associated with negative subjective symptoms, including cognitive complaints. Each condition likely explains some degree of unique variance in symptom reporting. PTSD is associated with poorer objective cognition on some tasks, including processing speed, executive functioning, and learning/memory. Implications are explored.

Cumulative Blast Impulse Is Predictive for Changes in Chronic Neurobehavioral Symptoms Following Low Level Blast Exposure during Military Training

INTRODUCTION

Cumulative low-level blast exposure during military training may be a significant occupational hazard, increasing the risk of poor long-term outcomes in brain function. US Public Law 116-92 section 717 mandates that US Department of Defense agencies document the blast exposure of each Service member to help inform later disability and health care decisions. However, which empirical measures of training blast exposure, such as the number of incidents, peak overpressure, or impulse, best inform changes in the neurobehavioral symptoms reflecting brain health have not been established.

MATERIALS AND METHODS

This study was approved by the US Army Special Operations Command, the University of North Carolina at Chapel Hill, and the VA Puget Sound Health Care System. Using methods easily deployable across different organizational structures, this study sought to identify and measure candidate risk factors related to career occupational blast exposure predictive of changes in neurobehavioral symptom burden. Blast dosimetry-symptom relationships were first evaluated in mice and then tested in a military training environment. In mice, the righting time neurobehavioral response was measured after exposure to a repetitive low-level blast paradigm modeled after Special Operations training. In the military training environment, 23 trainees enrolled in a 6-week explosive breaching training course, 13 instructors, and 10 Service member controls without blast exposure participated in the study (46 total). All participants provided weekly Neurobehavioral Symptom Inventory (NSI) surveys. Peak blast overpressure, impulse, total number of blasts, Time in Low-Level Blast Occupation, and Time in Service were analyzed by Bayesian analysis of regression modeling to determine their probability of influence on the post-training symptoms reported by participants.

RESULTS

We tested the hypothesis that cumulative measures of low-level blast exposure were predictive of changes in neurobehavioral symptoms. In mice, repetitive blast resulted in reduced righting times correlated with cumulative blast impulse. In Service members, peak blast overpressure, impulse, total number of blasts, Time in Low-Level Blast Occupation, and Time in Service all showed strong evidence of influence on NSI scores after blast exposure. However, only models including baseline NSI scores and cumulative blast impulse provided significant predictive value following validation.

CONCLUSIONS

These results indicate that measures of cumulative blast impulse may have utility in predicting changes in NSI scores. Such paired dosimetry-symptom measures are expected to be an important tool in safely guiding Service members' occupational exposure and optimizing force readiness and lethality.

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.

Age of First Exposure to Contact Sports Is Not Associated With Worse Later-In-Life Brain Health in a Cohort of Community-Dwelling Older Men

OBJECTIVE

To evaluate whether early age of first exposure to contact sports (AFE-CS) is associated with worse long-term brain health outcomes.

DESIGN

A cross-sectional, survey study of older men with a history of contact sport participation was completed.

SETTING

Tertiary care facility.

PARTICIPANTS

A cohort of community-dwelling older men dichotomized by using AFE-CS (<12 years vs ≥12 years).

INTERVENTIONS

Independent variables included a dichotomized group of AFE-CS (<12 years vs ≥12 years).

MAIN OUTCOME MEASURES

Brain health outcomes measured by depression, anxiety, cognitive difficulties, and neurobehavioral symptoms. Endorsements of general health problems, motor symptoms, and psychiatric history were also collected. Age of first exposure groups was compared using t tests, χ2 tests, and multivariable linear regressions, which included the following covariates: age, number of prior concussions, and total years of contact sport.

RESULTS

Of 69 men aged 70.5 ± 8.0 years, approximately one-third of the sample (34.8%) reported AFE-CS before age 12 years. That group had more years of contact sports (10.8 ± 9.2 years) compared with those with AFE-CS ≥12 (5.6 ± 4.5 years; P = 0.02). No differences were found after univariate testing between AFE-CS groups on all outcomes (P-values >0.05). Multivariable models suggest that AFE-CS is not a predictor of depression or anxiety. Those in the AFE-CS <12 group had fewer cognitive difficulties (P = 0.03) and fewer neurobehavioral symptoms (P = 0.03).

CONCLUSIONS

Those with AFE-CS <12 to contact sports did not have worse long-term brain health outcomes compared with those with AFE-CS ≥12. Individuals with AFE-CS <12 had significantly lower British Columbia Cognitive Complaints Inventory and Neurobehavioral Symptom Inventory scores compared with those with AFE-CS ≥12.

CLINICAL RELEVANCE

The benefits of earlier AFE-CS may outweigh the risks of head strikes and result in comparable long-term brain health outcomes.

Gender Disparities in Neurobehavioral Symptoms and the Role of Post-Traumatic Symptoms in US Service Members Following Mild Traumatic Brain Injury

Women are more directly involved in combat operations today than ever before, currently making up 18.6% of officers and 16.8% of enlisted personnel in the United States military. However, women continue to be under-represented in military research. Studies that do consider gender differences in traumatic brain injury (TBI) outcomes have shown that women report significantly more post-concussive symptoms than men. Conclusions for true gender differences related to TBI are hard to make without controlling for non-TBI factors. The effects previously identified in the literature may be an artifact of how men and women differ in their response to injury, unrelated to the neurological recovery process associated with TBI. The objective of this study was to examine the effects of gender specifics on mild TBI (mTBI) sequelae on injured and uninjured control groups, and to investigate the role of post-traumatic stress disorder (PTSD) on symptom reporting. It should be noted that the terms "gender" and "men/women" are used in this article in place of "sex" or "males/females" given that we are not discussing biological attributes. A total of 966 United States military service members and veterans were included in the study. Of the total sample, 455 men and 46 women were in the mTBI group, 285 men and 31 women were in the injured controls group (IC), and 111 men and 38 women in the non-injured controls group (NIC). Post-concussive and quality of life symptoms were compared for men and women while controlling for combat exposure. MTBI and IC groups were also stratified by PTSD presentation. Measures used included the Neurobehavioral Symptom Inventory (NSI), PTSD Checklist (PCL-C), Traumatic Brain Injury Quality of Life (TBI-QOL), and Combat Exposure Scale. In the mTBI group, women had worse scores on NSI total, NSI Somatosensory and Affective clusters, and the TBI-QOL Anxiety, Fatigue, and Headache scales (n2 = 0.018-0.032, small to small-medium effect sizes). When PTSD was present, women had worse scores on the NSI Somatosensory cluster only (n2 = 0.029, small-medium effect size). In contrast, when PTSD was absent, women had worse scores than men on the NSI Somatosensory and Affective clusters, and the TBI-QOL Anxiety and Headache scales (n2 = 0.032-0.063, small to medium effect sizes). In the IC group, women had worse scores on the NSI Cognitive cluster and the TBI-QOL Fatigue and Pain Interference scales (n2 = 0.024-0.042, small to small-medium effect sizes). However, group differences were no longer found when stratified by PTSD sub-groups. In the NIC group, there were no significant group differences for any analyses. We were able to identify symptoms unique to women recovering from mTBI that were not present following other forms of physical injury or in healthy controls. However, the impact of PTSD exacerbates the symptom profile and its comorbidity with mTBI equates to most of the noted gender differences.

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 ( R2 Δ = 0.143-0.207), and worse cognitive concerns in the MTBI group ( R2 Δ = 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.

Importance of validity testing in psychiatric assessment: evidence from a sample of multimorbid post-9/11 veterans

OBJECTIVE

Performance validity (PVTs) and symptom validity tests (SVTs) are necessary components of neuropsychological testing to identify suboptimal performances and response bias that may impact diagnosis and treatment. The current study examined the clinical and functional characteristics of veterans who failed PVTs and the relationship between PVT and SVT failures.

METHOD

Five hundred and sixteen post-9/11 veterans participated in clinical interviews, neuropsychological testing, and several validity measures.

RESULTS

Veterans who failed 2+ PVTs performed significantly worse than veterans who failed one PVT in verbal memory (Cohen's d = .60-.69), processing speed (Cohen's d = .68), working memory (Cohen's d = .98), and visual memory (Cohen's d = .88-1.10). Individuals with 2+ PVT failures had greater posttraumatic stress (PTS; β = 0.16; p = .0002), and worse self-reported depression (β = 0.17; p = .0001), anxiety (β = 0.15; p = .0007), sleep (β = 0.10; p = .0233), and functional outcomes (β = 0.15; p = .0009) compared to veterans who passed PVTs. 7.8% veterans failed the SVT (Validity-10; ≥19 cutoff); Multiple PVT failures were significantly associated with Validity-10 failure at the ≥19 and ≥23 cutoffs (p's < .0012). The Validity-10 had moderate correspondence in predicting 2+ PVTs failures (AUC = 0.83; 95% CI = 0.76, 0.91).

CONCLUSION

PVT failures are associated with psychiatric factors, but not traumatic brain injury (TBI). PVT failures predict SVT failure and vice versa. Standard care should include SVTs and PVTs in all clinical assessments, not just neuropsychological assessments, particularly in clinically complex populations.

Convergent and Discriminant Validity of the Blast Exposure Threshold Survey in United States Military Service Members and Veterans

The Blast Exposure Threshold Survey (BETS) is a recently developed and promising new self-report measure of lifetime blast exposure (LBE). However, there are no studies that have examined the psychometric properties of the BETS, which currently limits its clinical utility. The purpose of this study was to examine the convergent and discriminant validity of the BETS by comparing the BETS Generalized Blast Exposure Value (GBEV) to six variables hypothesized to be associated with LBE (i.e., single-item LBE, combat exposure, years in the military, number of combat deployments, and military occupation specialty [MOS]) and three variables hypothesized not to be associated with LBE (i.e., age at the time of injury, estimated pre-morbid Full-Scale Intelligence Quotient [FSIQ], and resilience). Participants were 202 United States service members and veterans prospectively enrolled from three military medical treatment facilities (68.7%) and via community recruitment initiatives (31.3%). Participants completed the BETS, Combat Exposure Scale (CES), Deployment Risk and Resiliency Inventory-2 Combat Experiences (DRRI-2 CE), Traumatic Brain Injury-Quality of Life Resilience scale, and a brief structured interview. For some analyses, participants were classified into two blast risk MOS groups: high (n = 89) and low (n = 94). The BETS GBEV was not significantly correlated with all three non-blast related variables (rs = 0.01 to rs = -0.12). In contrast, GBEV was significantly (p < 0.001) associated with all blast-related variables; single-item LBE (rs = 0.76), CES (rs = 0.58), number of combat deployments (rs = 0.53), DRRI-2 CE (rs = 0.48), and high blast risk MOS (r = 0.36, medium effect size). However, a stronger relationship was found between the blast-related variables and three modified GBEV scores when excluding some small weapons categories; single-item LBE (rs = 0.80-0.82), CES (rs = 0.64-0.67), number of combat deployments (rs = 0.56), DRRI-2 CE (rs = 0.51-0.53), and high blast risk MOS (r = 0.42-0.49, medium-large effect size). This is the first study to examine the psychometric properties of the BETS. Overall, these results offer support for the convergent and discriminant validity of the BETS. In order to ensure that the BETS can be confidently used as a valid and reliable measure of LBE, more research is needed to further examine the psychometric properties of the test, particularly with regard to the establishment of test-retest reliability.

High Lifetime Blast Exposure Using the Blast Exposure Threshold Survey Is Associated With Worse Warfighter Brain Health Following Mild Traumatic Brain Injury

The purpose of this study was to extend previous research by examining the relationship between lifetime blast exposure and neurobehavioral functioning after mild TBI (MTBI) by (a) using a comprehensive measure of lifetime blast exposure, and (b) controlling for the influence of post-traumatic stress disorder (PTSD). Participants were 103 United States service members and veterans (SMVs) with a medically documented diagnosis of MTBI, recruited from three military treatment facilities (74.8%) and community-based recruitment initiatives (25.2%, e.g., social media, flyers). Participants completed a battery of neurobehavioral measures 12 or more months post-injury (Neurobehavioral Symptom Inventory, PTSD-Checklist PCLC, TBI-Quality of Life), including the Blast Exposure Threshold Survey (BETS). The sample was classified into two lifetime blast exposure (LBE) groups: High (n = 57) and Low (n = 46) LBE. In addition, the sample was classified into four LBE/PTSD subgroups: High PTSD/High LBE (n = 38); High PTSD/Low LBE (n = 19); Low PTSD/High LBE (n = 19); and Low PTSD/Low LBE (n = 27). The High LBE group had consistently worse scores on all neurobehavioral measures compared with the Low LBE group. When controlling for the influence of PTSD (using ANCOVA), however, only a handful of group differences remained. When comparing measures across the four LBE/PTSD subgroups, in the absence of clinically meaningful PTSD symptoms (i.e., Low PTSD), participants with High LBE had worse scores on the majority of neurobehavioral measures (e.g., post-concussion symptoms, sleep, fatigue). When examining the total number of clinically elevated measures, the High LBE subgroup consistently had a greater number of clinically elevated scores compared with the Low LBE subgroup for the majority of comparisons (i.e., four to 15 or more elevated symptoms). In contrast, in the presence of clinically meaningful PTSD symptoms (i.e., High PTSD), there were no differences between High versus Low LBE subgroups for all measures. When examining the total number of clinically elevated measures, however, there were meaningful differences between High versus Low LBE subgroups for those comparisons that included a high number of clinically elevated scores (i.e., six to 10 or more), but not for a low number of clinically elevated scores (i.e., one to five or more). High LBE, as quantified using a more comprehensive measure than utilized in past research (i.e., BETS), was associated with worse overall neurobehavioral functioning after MTBI. This study extends existing literature showing that lifetime blast exposure, that is largely subconcussive, may negatively impact warfighter brain health and readiness beyond diagnosable brain injury.

Poorer Inhibitory Control Uniquely Contributes to Greater Functional Disability in Post-9/11 Veterans

OBJECTIVE

Post-9/11 Veterans endorse greater self-reported functional disability than 80% of the adult population. Previous studies of trauma-exposed populations have shown that increased post-traumatic stress disorder (PTSD) and depressive symptoms are consistently associated with greater disability. Additionally, poorer cognitive performance in the domain of executive functions, particularly inhibitory control, has been associated with disability, though it is unclear if this effect is independent of and/or interacts with PTSD and depression.

METHOD

Three overlapping samples of n = 582, 297, and 183 combat-deployed post-9/11 Veterans completed comprehensive assessments of executive functions, PTSD and depressive symptoms, and self-reported World Health Organization Disability Assessment Schedule-II (WHODAS II).

RESULTS

Poorer performance on measures of inhibitory control (Delis-Kaplan Executive Functioning System Color-Word Interference-CWI Test and gradual-onset Continuous Performance Test-gradCPT), but not other executive functions, were significantly associated with greater disability on the WHODAS II (ρ's = -.13 and -.13, p = .002 and .026, respectively). CWI inhibitory control measures accounted for unique variance in disability after controlling for PTSD and depressive symptoms (R2 change = 0.02, p < .001). Further, CWI significantly moderated the effect of depressive symptoms on disability, such that better inhibitory control weakened the relationship between depression and disability.

CONCLUSIONS

Inhibitory control deficits are uniquely associated with increased disability in combat-deployed post-9/11 Veterans, and better inhibitory control abilities may serve as a protective factor for depressive symptoms leading to increased disability.

KEY POINTS

An Emotion-Driven Vocal Biomarker-Based PTSD Screening Tool

Goal: This paper introduces an automated post-traumatic stress disorder (PTSD) screening tool that could potentially be used as a self-assessment or inserted into routine medical visits to aid in PTSD diagnosis and treatment. Methods: With an emotion estimation algorithm providing arousal (excited to calm) and valence (pleasure to displeasure) levels through discourse, we select regions of the acoustic signal that are most salient for PTSD detection. Our algorithm was tested on a subset of data from the DVBIC-TBICoE TBI Study, which contains PTSD Check List Civilian (PCL-C) assessment scores. Results: Speech from low-arousal and positive-valence regions provide the highest discrimination for PTSD. Our model achieved an AUC (area under the curve) of 0.80 in detecting PCL-C ratings, outperforming models with no emotion filtering (AUC = 0.68). Conclusions: This result suggests that emotion drives the selection of the most salient temporal regions of an audio recording for PTSD detection.

Associations between changes in somatic and psychiatric symptoms and disability alterations in recent-era U.S. veterans

Cross-sectional work suggests that deployment-related posttraumatic sequelae are associated with increased disability in U.S. veterans deployed following the September 11, 2001 (9/11), terrorist attacks. However, few studies have examined the psychiatric and somatic variables associated with changes in functional disability over time. A total of 237 post-9/11 veterans completed comprehensive assessments of psychiatric and cognitive functioning, as well as a disability questionnaire, at baseline and 2-year follow-up. At baseline, higher levels of PTSD, depressive, and pain-related symptoms were associated with baseline global functional disability, semipartial r² = .036-.044. Changes in symptoms of PTSD, depression, pain, and sleep, but not anxiety or alcohol use, were independently associated with changes in functional disability, semipartial r² = .017-.068. Baseline symptoms of these conditions were unrelated to changes in disability, and cognitive performance was unrelated to disability at any assessment point. Together, this suggests that changes in psychiatric and somatic symptoms are tightly linked with changes in functional disability and should be frequently monitored, and even subclinical symptoms may be a target of intervention.

Extracellular vesicle neurofilament light is elevated within the first 12-months following traumatic brain injury in a U.S military population

Traumatic brain injury (TBI) can be associated with long-term neurobehavioral symptoms. Here, we examined levels of neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) in extracellular vesicles isolated from blood, and their relationship with TBI severity and neurobehavioral symptom reporting. Participants were 218 service members and veterans who sustained uncomplicated mild TBIs (mTBI, n = 107); complicated mild, moderate, or severe TBIs (smcTBI, n = 66); or Injured controls (IC, orthopedic injury without TBI, n = 45). Within one year after injury, but not after, NfL was higher in the smcTBI group than mTBI (p = 0.001, d = 0.66) and IC (p = 0.001, d = 0.35) groups, which remained after controlling for demographics and injury characteristics. NfL also discriminated the smcTBI group from IC (AUC:77.5%, p < 0.001) and mTBI (AUC:76.1%, p < 0.001) groups. No other group differences were observed for NfL or GFAP at either timepoint. NfL correlated with post-concussion symptoms (rs = - 0.38, p = 0.04) in the mTBI group, and with PTSD symptoms in mTBI (rs = - 0.43, p = 0.021) and smcTBI groups (rs = - 0.40, p = 0.024) within one year after injury, which was not confirmed in regression models. Our results suggest the potential of NfL, a protein previously linked to axonal damage, as a diagnostic biomarker that distinguishes TBI severity within the first year after injury.

Low resilience following traumatic brain injury is strongly associated with poor neurobehavioral functioning in U.S. military service members and veterans

OBJECTIVE

The purpose of this study was to examine the relationship between resilience and self-reported neurobehavioral functioning following traumatic brain injury (TBI) in U.S. military service members and veterans (SMVs). A secondary objective was to examine the interaction between resilience and posttraumatic stress disorder (PTSD) on neurobehavioral functioning.

METHOD

Participants included 795 SMVs classified into four groups: Uncomplicated Mild TBI (MTBI; n=300); Complicated Mild, Moderate, Severe, or Penetrating TBI (STBI, n 162); Injured Controls (IC, n=185); and Non-injured Controls (NIC, n=148). Two independent cohorts were evaluated - those assessed within 1-year of injury and those assessed 10-years post-injury. SMVs completed self-report measures including the PTSD Checklist-Civilian version, Neurobehavioral Symptom Inventory, and TBI-Quality of Life.

RESULTS

Results showed that (1) lower resilience was strongly associated with poorer neurobehavioral functioning across all groups at 1-year and 10-years post-injury, and (2) PTSD and resilience had a robust influence on neurobehavioral functioning at both time periods post-injury, such that SMVs with PTSD and low resilience displayed the poorest neurobehavioral functioning.

CONCLUSION

Results suggest that regardless of injury group and time since injury, resilience and PTSD strongly influence neurobehavioral functioning following TBI among SMVs. Future research evaluating interventions designed to enhance resilience in this population is indicated.

Clinical utility of PTSD, resilience, sleep, and blast as risk factors to predict poor neurobehavioral functioning following traumatic brain injury: A longitudinal study in U.S. military service members

PURPOSE

This study examined the clinical utility of post-traumatic stress disorder (PTSD), low resilience, poor sleep, and lifetime blast exposure as risk factors for predicting future neurobehavioral outcome following traumatic brain injury (TBI).

METHODS

Participants were 591 U.S. military service members and veterans who had sustained a TBI (n = 419) or orthopedic injury without TBI (n = 172). Participants completed the Neurobehavioral Symptom Inventory, PTSD Checklist, and the TBI-Quality of Life (TBI-QOL) scale at baseline and follow-up.

RESULTS

Using the four risk factors at baseline, 15 risk factor combinations were examined by calculating odds ratios to predict poor neurobehavioral outcome at follow-up (i.e., number of abnormal scores across five TBI-QOL scales [e.g., Fatigue, Depression]). The vast majority of risk factor combinations resulted in odds ratios that were considered to be clinically meaningful (i.e., ≥ 2.5) for predicting poor outcome. The risk factor combinations with the highest odds ratios included PTSD singularly, or in combination with poor sleep and/or low resilience (odds ratios = 4.3-72.4). However, poor sleep and low resilience were also strong predictors in the absence of PTSD (odds ratios = 3.1-29.8).

CONCLUSION

PTSD, poor sleep, and low resilience, singularly or in combination, may be valuable risk factors that can be used clinically for targeted early interventions.

Apolipoprotein E e4 is associated with worse self-reported neurobehavioral symptoms following uncomplicated mild traumatic brain injury in U.S. military service members

Past research has found a relationship between the apolipoprotein E (APOE) e4 allele and worse neurobehavioral functioning following mild traumatic brain injury (MTBI) in civilian populations. The purpose of this study was to examine this relationship in service members and veterans (SMVs) following MTBI. Participants were 151 SMVs (103 uncomplicated MTBI; 48 Injured Controls [IC]) prospectively enrolled in the DVBIC-TBICoE 15-Year Longitudinal TBI Study. Participants completed a battery of self-reported neurobehavioral symptom measures on average 76.2 months post-injury (SD = 31.8). APOE genotyping was undertaken using non-fasting blood samples. Participants were classified into four subgroups based on injury (MTBI vs. IC) and APOE e4 allele status (e4 present/absent). In the IC group, there were no significant differences across APOE e4 status subgroups for all measures. In the MTBI group, participants with the APOE e4 allele had significantly worse scores on measures of depression, pain, anxiety, grief, positive well-being, social participation, and resilience compared to those without the e4 allele (d = .44 to d = .69). When comparing the number of 'clinically elevated' neurobehavioral measures simultaneously, the MTBI/e4 present subgroup consistently had a higher number of elevated measures compared to the MTBI/e4 absent, IC/e4 present, and IC/e4 absent subgroups. The APOE e4 allele was associated with poorer neurobehavioral outcome in SMVs in the chronic phase of recovery following MTBI. APOE e4 could be incorporated into screening tools to predict SMVs at risk for poor long-term neurobehavioral outcome in an effort to provide early intervention to improve long-term clinical outcome.

Sleep disturbances following traumatic brain injury are associated with poor neurobehavioral outcomes in U.S. military service members and veterans

STUDY OBJECTIVES

This study examined whether sleep disturbances were associated with neurobehavioral outcome following a traumatic brain injury (TBI) in a well characterized group of service members and veterans.

METHODS

Six-hundred and six participants were enrolled into the Defense and Veterans Brain Injury Center, 15-Year Longitudinal TBI study. All participants completed a battery of tests measuring self-reported sleep disturbances, neurobehavioral symptoms, and Posttraumatic Stress Disorder PTSD symptoms. Data were analyzed using analysis of variance with post-hoc comparisons. Four groups were analyzed separately: uncomplicated mild TBI (MTBI); complicated mild, moderate, severe, or penetrating - combined TBI (CTBI); injured controls (IC, i.e., orthopedic or soft-tissue injury without TBI); and non-injured controls (NIC).

RESULTS

A higher proportion of the MTBI group reported moderate-severe sleep disturbances (66.5%) compared to the IC (54.9%), CTBI (47.5%), and NIC groups (34.3%). Participants classified as having Poor Sleep had significantly worse scores on the majority of TBI-QOL scales compared to those classified as having Good Sleep, regardless of TBI severity or the presence of TBI. There was a significant interaction between sleep disturbances and PTSD. While sleep disturbances and PTSD by themselves were significant factors associated with worse outcome, both factors combined resulted in worse outcome than either singularly.

CONCLUSIONS

Regardless of group (injured or NIC), sleep disturbances were common and were associated with significantly worse neurobehavioral functioning. When experienced concurrently with PTSD, sleep disturbances pose significant burden to service members and veterans.

The Boston Assessment of Traumatic Brain Injury-Lifetime Semistructured Interview for Assessment of TBI and Subconcussive Injury Among Female Survivors of Intimate Partner Violence: Evidence of Research Utility and Validity

OBJECTIVE

To adapt the Boston Assessment of TBI-Lifetime (BAT-L) interview specifically for female survivors of intimate partner violence (IPV), validate the adapted BAT-L/IPV, and report the prevalence of head injury.

SETTING

The BAT-L is the first validated instrument to diagnose traumatic brain injuries (TBIs) throughout the life span for post-9/11 veterans. The BAT-L/IPV was adapted to target diagnostic issues belonging exclusively to IPV while maintaining its life span approach.

PARTICIPANTS

Community-dwelling convenience sample of 51 female survivors of IPV with subthreshold (n = 10) or full diagnostic criteria (n = 41) of posttraumatic stress disorder.

DESIGN

Standard TBI criteria were evaluated using a semistructured clinical interview.

MAIN MEASURES

The BAT-L/IPV is compared with the Ohio State University TBI Identification Method (OSU-TBI-ID) scoring approach as the criterion standard.

RESULTS

Correspondence between the BAT-L/IPV and the OSU-TBI-ID score was excellent (Cohen κ = 0.86; Kendall τ-b = 0.89). Sensitivity = 89.3% (95% CI, 81.2-97.4); specificity = 98.3% (95% CI, 95.0-100); positive predictive value = 98.0% (95% CI, 94.2-100); and negative predictive value = 90.6% (95% CI, 83.5-97.7). On the BAT-L/IPV, more than one-third (35.3%) of IPV survivors reported TBI secondary to an IPV-related assault, 76.5% reported IPV subconcussive head injury, 31.4% reported attempted strangulation, and 37.3% reported non-IPV TBI.

CONCLUSIONS

The BAT-L/IPV performed well in diagnosing TBI in female IPV survivors as compared with the criterion standard. The prevalence of TBI was frequent; subconcussive head injury was pervasive. Greater awareness for head injury risk and increased diagnostic specificity of TBI in IPV survivors is needed.

Use of a randomized clinical trial design to study cognitive rehabilitation approaches to enhance warfighter performance

Within the military, cognitive readiness is essential to ensure the warfighter can return to highly demanding combat training and deployment operations. The warfighter must be able to make split second decisions and adapt to new tools and environments. After a traumatic brain injury, clinicians helping the warfighter must have techniques that address warfighter cognitive readiness. Current rehabilitation for cognitive complaints used in military medicine are modeled after civilian therapies which focus on remediating moderate to severe impairment through building compensatory strategies. This traditional approach to cognitive rehabilitation does not translate well to mild traumatic brain injury (mTBI) where impairments are subtle, nor does it meet the needs of our warfighters in deployed and combat training environments. Challenging our current methods is critical in adapting to the needs of this highly valued population to ensure that our warfighters are able to carry out mission critical decision making. Here we present a review of our best current practices for cognitive rehabilitation, describe the limitations our traditional approaches impose for mTBI in military personnel, and present an alternative treatment called Strategic Memory Advanced Reasoning Training (SMART) that can be adopted through a randomized clinical trial design. We propose directly comparing traditional treatment approaches with a novel cognitive rehabilitation strategy which has been well validated outside of the military setting. Procedures were developed to execute this clinical trial in a way that is most relevant to the study population by establishing ecologically valid outcome metrics.

The Impact of Common Psychiatric and Behavioral Comorbidities on Functional Disability Across Time and Individuals in Post-9/11 Veterans

Returning veterans often face multiple concurrent psychiatric and behavioral conditions that negatively impact reintegration into civilian life and are associated with functional disability. Understanding how conditions interact to negatively impact functioning is an important step toward developing holistic treatment approaches optimized for this population. This study utilized a cross-sectional and prospective longitudinal cohort design, applying regression algorithms to understand the relative contribution of common clinical issues to functional disability in U.S. veterans who served after the September 11, 2001 (9/11), terror attacks. Community-dwelling post-9/11 veterans (N = 397) completed detailed assessments, including common clinical condition diagnoses, combat experience, and demographics, which were used to predict functional disability (World Health Organization Disability Assessment Schedule); 205 participants were reassessed approximately 1-2 years after enrollment. Regression analyses showed a strong association between the predictor variables and functional disability, f ² = 1.488. Validation analyses showed a high prediction ability of functional disability to independent samples, r = .719, and across time in the same individuals, r = .780. The strongest predictors included current posttraumatic stress disorder, depressive disorder, sleep disturbance, and pain diagnoses. These results demonstrate the importance of considering multiple common co-occurring conditions when assessing functional disability in post-9/11 veterans and suggest that certain syndromes contribute the most unique information to predicting functional disability with high confidence. As most U.S. veterans utilize private healthcare systems, these results have clinical utility for both Veterans Affairs and civilian healthcare practitioners in assessing and monitoring functional disability in post-9/11 veterans over time.

Meningeal blood-brain barrier disruption in acute traumatic brain injury

The meninges serve as a functional barrier surrounding the brain, critical to the immune response, and can be compromised following head trauma. Meningeal enhancement can be detected on contrast-enhanced MRI in patients presenting with acute traumatic brain injury, even when head CT is negative. Following head trauma, gadolinium-based contrast appears to extravasate from the vasculature, enhancing the dura within minutes, and later permeates the subarachnoid space. The aims of this study were to characterize the initial kinetics of the uptake of contrast agent after injury and the delayed redistribution of contrast enhancement in the subarachnoid space in hyperacute patients. Neuroimaging was obtained prospectively in two large ongoing observational studies of patients aged 18 years or older presenting to the emergency department with suspected acute head injury. Dynamic contrast-enhanced MRI studies in a cohort of consecutively enrolling patients with mild traumatic brain injury (n = 36) determined that the kinetic half-life of dural-related meningeal enhancement was 1.3 ± 0.6 min (95% enhancement within 6 min). The extravasation of contrast into the subarachnoid space was investigated in a cohort of CT negative mild traumatic brain injury patients initially imaged within 6 h of injury (hyperacute) who subsequently underwent a delayed MRI, with no additional contrast administration, several hours after the initial MRI. Of the 32 patients with delayed post-contrast imaging, 18 (56%) had conspicuous expansion of the contrast enhancement into the subarachnoid space, predominantly along the falx and superior sagittal sinus. Patients negative for traumatic meningeal enhancement on initial hyperacute MRI continued to have no evidence of meningeal enhancement on the delayed MRI. These studies demonstrate that (i) the initial enhancement of the traumatically injured meninges occurs within minutes of contrast injection, suggesting highly permeable meningeal vasculature, and that (ii) contrast in the meninges redistributes within the subarachnoid space over the period of hours, suggesting a compromise in the blood-brain and/or blood-cerebrospinal barriers. Data from the parent study indicate that up to one in two patients with mild traumatic brain injury have traumatic brain injury on acute (<48 h) MRI, with a higher prevalence seen in patients with moderate or severe traumatic brain injury. The current study's findings of traumatic meningeal enhancement and the subsequent delayed extravasation of contrast into the subarachnoid spaces indicate that a substantial percentage of patients with even mild traumatic brain injury may have a transient disruption in barriers separating the vasculature from the brain.

Multidimensional Malingering Criteria for Neuropsychological Assessment: A 20-Year Update of the Malingered Neuropsychological Dysfunction Criteria

OBJECTIVES

Empirically informed neuropsychological opinion is critical for determining whether cognitive deficits and symptoms are legitimate, particularly in settings where there are significant external incentives for successful malingering. The Slick, Sherman, and Iversion (1999) criteria for malingered neurocognitive dysfunction (MND) are considered a major milestone in the field's operationalization of neurocognitive malingering and have strongly influenced the development of malingering detection methods, including serving as the criterion of malingering in the validation of several performance validity tests (PVTs) and symptom validity tests (SVTs) (Slick, D.J., Sherman, E.M.S., & Iverson, G. L. (1999). Diagnostic criteria for malingered neurocognitive dysfunction: Proposed standards for clinical practice and research. The Clinical Neuropsychologist, 13(4), 545-561). However, the MND criteria are long overdue for revision to address advances in malingering research and to address limitations identified by experts in the field.

METHOD

The MND criteria were critically reviewed, updated with reference to research on malingering, and expanded to address other forms of malingering pertinent to neuropsychological evaluation such as exaggeration of self-reported somatic and psychiatric symptoms.

RESULTS

The new proposed criteria simplify diagnostic categories, expand and clarify external incentives, more clearly define the role of compelling inconsistencies, address issues concerning PVTs and SVTs (i.e., number administered, false positives, and redundancy), better define the role of SVTs and of marked discrepancies indicative of malingering, and most importantly, clearly define exclusionary criteria based on the last two decades of research on malingering in neuropsychology. Lastly, the new criteria provide specifiers to better describe clinical presentations for use in neuropsychological assessment.

CONCLUSIONS

The proposed multidimensional malingering criteria that define cognitive, somatic, and psychiatric malingering for use in neuropsychological assessment are presented.

Concordance of Embedded Performance and Symptom Validity Tests and Associations with Mild Traumatic Brain Injury and Posttraumatic Stress Disorder among Post-9/11 Veterans

Objective

The present study explored both embedded symptom (SVT) and performance (PVT) validity test scores within a post-9/11 veteran sample to elucidate the degree to which there is concordance between validity indicators, as well as how frequently one SVT and four PVT indicators were failed in screened mild traumatic brain injury (mTBI) and diagnosed posttraumatic stress disorder (PTSD).

Method

A total of 114 post-9/11 veterans were evaluated utilizing the Neurobehavioral Symptom Inventory (NSI) Validity-10, four embedded PVTs, mTBI screening, and a diagnostic interview for PTSD.

Results

While we found concordance between embedded PVTs and the NSI Validity-10 at select cutoffs (i.e., ≥13, ≥19), symptom and performance validity indicators were clinically dissociable in that only SVT significantly predicted diagnosed PTSD and screened mTBI.

Conclusions

Dissociation between symptom and performance validity may be clinically useful when interpreting neuropsychological evaluation findings in post-9/11 veterans with a history of mTBI or PTSD.

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

OBJECTIVE

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Posttraumatic Stress Disorder is a Stronger Predictor of Long-Term Neurobehavioral Outcomes Than Traumatic Brain Injury Severity

Concurrent posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) is common in military populations. The purpose of this study was to examine long-term neurobehavioral outcomes in service members and veterans (SMVs) with versus without PTSD symptoms following TBI of all severities. Participants were 536 SMVs prospectively enrolled from three military medical treatment facilities who were recruited into three experimental groups: TBI, injured controls (IC), and noninjured controls (NIC). Participants completed the PTSD Checklist, Neurobehavioral Symptom Inventory, and the TBI-Quality of Life (TBI-QOL) and were divided into six subgroups based on the three experimental categories, two PTSD categories (i.e., present vs. absent), and two broad TBI severity categories (unMTBI, which included uncomplicated mild TBI; and smcTBI, which included severe TBI, moderate TBI, and complicated mild TBI): (a) NIC/PTSD-absent, (b) IC/PTSD-absent, (c) unMTBI/PTSD-absent, (d) unMTBI/PTSD-present, (e) smcTBI/PTSD-absent, and (f) smcTBI/PTSD-present. There were significant main effects across the six groups for all TBI-QOL measures, ps < .001. Select pairwise comparisons revealed significantly lower scores, p < .001, on all TBI-QOL measures in the PTSD-present groups when compared to the PTSD-absent groups within the same TBI severity classification, ds = 0.90-2.11. In contrast, when controlling for PTSD, there were no significant differences among the TBI severity groups for any TBI-QOL measures. These results provide support for the strong influence of PTSD but not TBI severity on neurobehavioral outcomes following TBI. Concurrent PTSD and TBI of all severities should be considered a risk factor for poor long-term neurobehavioral outcomes that require ongoing monitoring.

Validating the usefulness of the NSI validity-10 with the MMPI-2-RF

Purpose/Aim of the Study: The Neurobehavioral Symptom Inventory (NSI) is a 22-item self-report measure created to quantify the somatosensory, cognitive, and affective symptoms of Post-concussive Syndrome. Developers of the NSI used a subset of 10 items, the Validty-10, to measure symptom overreporting. We compared the Validity-10 versus the remaining NSI items (i.e., the Remaining-12) for how accurately they detect symptom exaggeration on the Minnesota Multiphasic Personality Inventory Second Edition - Restructured Form (MMPI-2-RF).Materials and Methods: We used a sample of 45 veterans evaluated in a Polytrauma/TBI Clinic of a Midwest VA Healthcare System who completed the NSI and MMPI-2-RF.Results: The Vaidity-10, Remaining-12, and Total Score all strongly correlated with mean of the MMPI-2-RF validity scales (r = .65, .67, and .70, respectively), illustrating equivalency among the various NSI scores. Groups were created based on significant T score elevation on any MMPI-2-RF validity scale (i.e. F-r > 119, or Fp-r, F-s, FBS, or RBS > 99). ROC analyses demonstrated that areas under the curve were equivalent for NSI Total Score (.84), Validity-10 (.81), and Remaining-12 (.81) in detecting overreporting.Conclusions: These findings do not support the notion that the Validity-10 has unique utility as an embedded symptom validity scale and highlights the likelihood that NSI Total Score can also serve this function.

Translingual Neurostimulation for the Treatment of Chronic Symptoms Due to Mild-to-Moderate Traumatic Brain Injury

OBJECTIVE

To compare the efficacy of high- and low-frequency noninvasive translingual neurostimulation (TLNS) plus targeted physical therapy (PT) for treating chronic balance and gait deficits due to mild-to-moderate traumatic brain injury (mmTBI).

DESIGN

Participants were randomized 1:1 in a 26-week double-blind phase 1/2 study (NCT02158494) with 3 consecutive treatment stages: in-clinic, at-home, and no treatment. Arms were high-frequency pulse (HFP) and low-frequency pulse (LFP) TLNS.

SETTING

TLNS plus PT training was initiated in-clinic and then continued at home.

PARTICIPANTS

Participants (N=44; 18-65y) from across the United States were randomized into the HFP and LFP (each plus PT) arms. Forty-three participants (28 women, 15 men) completed at least 1 stage of the study. Enrollment requirements included an mmTBI ≥1 year prior to screening, balance disorder due to mmTBI, a plateau in recovery with current PT, and a Sensory Organization Test (SOT) score ≥16 points below normal.

INTERVENTIONS

Participants received TLNS (HFP or LFP) plus PT for a total of 14 weeks (2 in-clinic and 12 at home), twice daily, followed by 12 weeks without treatment.

MAIN OUTCOME MEASURES

The primary endpoint was change in SOT composite score from baseline to week 14. Secondary variables (eg, Dynamic Gait Index [DGI], 6-minute walk test [6MWT]) were also collected.

RESULTS

Both arms had a significant (P<.0001) improvement in SOT scores from baseline at weeks 2, 5, 14 (primary endpoint), and 26. DGI scores had significant improvement (P<.001-.01) from baseline at the same test points; 6MWT evaluations after 2 weeks were significant. The SOT, DGI, and 6MWT scores did not significantly differ between arms at any test point. There were no treatment-related serious adverse events.

CONCLUSIONS

Both the HFP+PT and LFP+PT groups had significantly improved balance scores, and outcomes were sustained for 12 weeks after discontinuing TLNS treatment. Results between arms did not significantly differ from each other. Whether the 2 dosages are equally effective or whether improvements are because of provision of PT cannot be conclusively established at this time.

Clinical utility of WAIS-IV 'excessive decline from premorbid functioning' scores to detect invalid test performance following traumatic brain injury

Objective: Excessive Decline from Premorbid Functioning (EDPF), an atypical discrepancy between demographically predicted and obtained Wechsler Adult Intelligence Scale-4th Edition (WAIS-IV) scores, has been recently proposed as a potential embedded performance validity test (PVT). This study examined the clinical utility of EDPF scores to detect invalid test performance following traumatic brain injury (TBI).Methods: Participants were 194 U.S. military service members who completed neuropsychological testing on average 2.4 years (SD = 4.0) following uncomplicated mild, complicated mild, moderate, severe, or penetrating TBI (Age: M = 34.0, SD = 9.9). Using TBI severity and PVT performance (i.e., PVT Pass/Fail), participants were classified into three groups: Uncomplicated Mild TBI-PVT Fail (MTBI-Fail; n = 21), Uncomplicated Mild TBI-PVT Pass (MTBI-Pass; n = 94), and Complicated Mild to Severe/Penetrating TBI-PVT Pass (CM/STBI-Pass; n = 79). Seven EDPF measures were calculated by subtracting WAIS-IV obtained index scores from the demographically predicted scores from the Test of Premorbid Functioning (TOPF). Cutoff scores to detect invalid test performance were examined for each EDPF measure separately.Results: The MTBI-Fail group had higher scores than the MTBI-Pass and CM/STBI-Pass groups on five of the seven EDPF measures (p<.05). Overall, the EDPF measure using the Processing Speed Index (EDPF-PSI) was the most useful score to detect invalid test performance. However, sensitivity was only low to moderate depending on the cutoff score used.Conclusions: These findings provide support for the use of EDPF as an embedded PVT to be considered along with other performance validity data when administering the WAIS-IV.

The Deployment Trauma Phenotype and Employment Status in Veterans of the Wars in Iraq and Afghanistan

OBJECTIVES

To determine the prevalence of comorbid mild traumatic brain injury (mTBI), posttraumatic stress disorder (PTSD), and depression, termed the deployment trauma phenotype (DTP), and its constituent diagnoses' impact on unemployment status in a national cohort of veterans.

SETTING

Retrospective analysis of the comprehensive TBI evaluation, a Veterans Affairs-wide protocol for assessing TBI, employment status, and psychiatric impressions.

PARTICIPANTS

The final data set consisted of 48 821 veterans.

MAIN OUTCOMES AND MEASURES

Frequency of mTBI, PTSD, and depression in isolation and combinations and their association with unemployment status.

RESULTS

Age- and education-adjusted risk ratios (RRs) showed that the mTBI-only group was the least likely to be unemployed, RR = 0.65 (0.59-0.71). By contrast, the greatest likelihood of unemployment was associated with membership in the DTP group, RR = 1.45 (1.36-1.56), and the comorbid PTSD and depression group, RR = 1.39 (1.27-1.52). Furthermore, the DTP was nearly 3 times more prevalent (16.4%) in this sample compared with comorbid PTSD and depression (5.7%), indicating that the DTP conveys risk for unemployment to a significantly greater number of individuals.

CONCLUSIONS AND RELEVANCE

The comorbid and interactive conditions of PTSD, depression, and mTBI, rather than mTBI in isolation, were linked to significant risk for unemployment in this veteran cohort. These findings suggest that multifaceted assessments and interventions to improve postdeployment reintegration are needed.

The Impact of Affective States on Postconcussive Symptoms in a TBI Population

The occurrence of persistent postconcussive symptoms (PCS) associated with traumatic brain injury (TBI) is an increasing cause of disability and lost productivity. The reasons for these persistent symptoms in a percentage of even mild TBI are poorly understood. The existence of comorbid conditions such as post-traumatic stress disorder or other traumatic injuries may be factors that impact the presence of PCS. We expect that greater levels of affective symptoms will be associated with increases in PCS assessed on the Neurobehavioral Symptom Inventory (NSI). TBI subjects (N = 69) who were seen 1 year post-injury were recruited from a larger cohort study of TBI. Subjects were administered the NSI, Brief Symptom Inventory-18 (BSI-18) and the Post Traumatic Stress Disorder Checklist (PCL). Data were analyzed using Spearman's rho correlations and analysis of variances. We found significant correlations between the four NSI factors and the three BSI factors and the PCL total score. Mild TBI subjects were found to have the highest correlations between affective and somatic symptoms. These findings support our hypothesis that affective states are associated with higher PCS reporting and that early identification and treatment may decrease PCS.

Psychosocial stress factors among mental health nursing students in KSA

OBJECTIVES

Although existing evidence suggests that nurses may experience significant stress during their training, less is known about the key elements responsible for the distress experienced by mental-health nursing students. This study has examined the psychosocial stress factors that influence mental-health nursing students in a Saudi University.

METHODS

This study has adopted a qualitative interpretive approach, using semi-structured interviews with 10 female fourth-year mental-health nursing students. After the interviews were digitally recorded and transcribed, they underwent content analysis using the NVIVO 10.1 application, generating the themes that emerge in this study.

RESULTS

The results of the present study make it possible to conceptualise the dynamics that impede the progress of students nearing the end of their final academic year. The analysis focuses on four main themes: (a) the clinical learning context; (b) discrimination against nurses; (c) interpersonal relationships; and (d) social challenges. The statements made by students were analysed for emerging themes; their experiences were subsequently grouped into eight sub-themes.

CONCLUSIONS

The study findings highlight the importance of encouraging students to strengthen peer relationships, improve their own psychological wellbeing, and embrace strategies for managing both personal and academic stress levels. They also reveal that understanding the expectations of students can provide a platform for recognising stressors. Effective interventions can be adopted to improve understanding of stress factors and subsequent stress responses among mental-health nursing students. These results may help to improve students' clinical, social, and academic outcomes.

Neurobehavioral symptom validity and performance validity in veterans: Evidence for distinct outcomes across data types

Self-reported traumatic brain injury (TBI) is common in combat veterans, and identification of psychiatric and neuropsychological consequences following TBI has become a priority for veteran healthcare. Given the importance of accurately capturing symptoms potentially related to TBI in VA settings, validity metrics are frequently used to evaluate both neuropsychological testing validity and the validity of symptom self-reports. The Validity-10 of the Neurobehavioral Symptom Inventory is one such metric that was designed to evaluate symptom over-reporting and thus identify individuals who may produce inconclusive testing profiles. However, the Validity-10's ability to predict objective effort during neuropsychological testing has not been sufficiently explored in veterans. Clinical evaluation data were collected from 295 veterans seeking treatment in a VA TBI clinic. We examined whether the Validity-10 can predict invalid performance on a battery of neuropsychological tests. Validity-10 was a poor predictor of performance validity metrics. Results provide a conceptual replication of earlier work demonstrating that performance and symptom validity are divergent. As such, separate evaluation of these domains is warranted during evaluations conducted in veteran TBI populations.

Do postconcussive symptoms from traumatic brain injury in combat veterans predict risk for receiving opioid therapy for chronic pain?

OBJECTIVES

Opioid therapy is contraindicated in patients with traumatic brain injury (TBI) with neuropsychological impairment, yet guidelines do not consistently predict practice. We evaluated independent risk for initiation of opioid therapy among combat veterans with chronic pain diagnoses and persistent postconcussive symptoms.

METHODS

We assembled a retrospective cohort of 53 124 Iraq and Afghanistan veterans in Veterans Affairs (VA) healthcare between October 2007 and March 2015 who received chronic pain diagnoses, completed a Comprehensive TBI Evaluation (CTBIE) and had not received opioid therapy in the prior year. Primary exposure variables were self-reported severe or very severe Emotional, Vestibular, Cognitive and Somatic/Sensory symptoms measured using the Neurobehavioral Symptom Inventory. Outcome measures were initiation of short-term and long-term opioid therapy within the year following CTBIE.

RESULTS

Self-reported severe and very severe postconcussive symptoms predicted initiation of long-term and short-term opioid use for chronic pain in both unadjusted and adjusted analyses. In adjusted analyses, all four postconcussive symptom domains significantly predicted initiation of long-term opioid therapy, with Emotional symptoms being the strongest predictor [ARR = 1.68 (1.52, 1.86)].

CONCLUSIONS

Increased opioid prescribing in veterans with self-reported severe persistent postconcussive symptoms indicates a need to educate prescribers and make non-opioid pain management options available for veterans with TBI and neuropsychological sequelae.

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.

Utility of the Validity-10 scale across the recovery trajectory following traumatic brain injury

The Validity-10 scale was recently developed to screen for symptom exaggeration in patients following traumatic brain injury (TBI). However, it has only been validated on patients with TBI largely in the chronic phase of recovery. The influence of time since injury on the Validity-10 scale was investigated in 2,661 male servicemembers with TBI presenting to six U.S. Defense and Veterans Brain Injury Centers. Participants completed the Neurobehavioral Symptom Inventory (NSI). The Validity-10 scale and NSI total score were both weakly statistically significantly (1) positively correlated with time since injury, (2) negatively correlated with bodily injury severity, and (3) higher in participants undergoing medical board evaluations than in participants who returned to duty or were still hospitalized. Participants were statistically more likely to screen positive for possible symptom exaggeration on the Validity-10 scale as time since injury increased. However, the Validity-10 scale was only weakly related to time since injury, TBI severity, bodily injury severity, disposition, age, and return to duty status. That false positives are not increased in the acute phase of recovery and that the Validity-10 scale is not strongly related to clinical factors support the use of the Validity-10 scale in the acute recovery phase and across the TBI recovery trajectory.

Epidemiology and prognosis of mild traumatic brain injury in returning soldiers

Objective:

Mild traumatic brain injury (mTBI; concussion) is common in returning service members yet limited definitive evidence exists on its prognosis.

Methods:

Almost 25,000 non–medically evacuated soldiers returning from Afghanistan or Iraq to 2 military bases between 2009 and 2014 were screened for mTBI. We invited a random sample to participate in the present study, oversampling those screening positive, resulting in 557 mTBI cases and 1,010 controls, of whom 366 cases and 599 controls completed 3-month follow-up evaluations. The criterion measure of screened mTBI was the Ohio State University Traumatic Brain Injury Identification Method. Postconcussive symptoms (PCS) were measured at follow-up with the Neurobehavioral Symptom Inventory. Symptoms reported at a severe or very severe level were considered clinically relevant.

Results:

About half (47%) of soldiers who had sustained an mTBI during this latest deployment reported PCS at 3-month follow-up vs 25% of controls: adjusted odds ratio 2.4 (1.8–3.2). The most commonly reported symptoms (cases vs controls) were sleep problems (30% vs 14%), forgetfulness (21% vs 9%), irritability (17% vs 8%), and headaches (15% vs 5%). mTBI cases were about twice as likely as controls to report receiving rehabilitative services and fair or poor health. Other predictors of PCS included posttraumatic stress, combat exposure, and noncephalic pain. A majority of both cases and controls reported traumatic brain injuries predating this latest deployment.

Conclusions:

In this nonclinical population of recently deployed soldiers, a substantial proportion of those who had sustained an mTBI were symptomatic 3 months postdeployment. Future studies need to include longer follow-up to measure symptom resolution.

Clinicaltrials.gov identifier:

NCT01847040.

Postconcussive symptom overreporting in Iraq/Afghanistan Veterans with mild traumatic brain injury

A comprehensive evaluation, including the assessment of neurobehavioral symptoms, has been instituted at the Department of Veterans Affairs (VA) healthcare system to address the large number of Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) Veterans returning with mild traumatic brain injuries (mTBIs). The Validity-10 is measure of symptom overreporting embedded within the Neurobehavioral Symptom Inventory, a component of the comprehensive evaluation that assesses postconcussive symptom severity. The Validity-10 is composed of 10 unlikely/low-frequency items and a validated cutoff score to identify postconcussive symptom overreporting. We examined the items and cutoff used in the initial development and validation study of the Validity-10 through retrospective chart reviews of 331 treatment-seeking Veterans who sustained an mTBI. The Validity-10 exhibited significant relationships with psychiatric variables, VA service connection, and neuropsychological performance validity (all p < 0.01), but nonsignificant relationships with demographic and injury variables (all p > 0.05). Furthermore, the Validity-10 modestly predicted neuropsychological performance validity test failure over and above psychiatric comorbidities and VA service connection. The present study supports the use of the Validity-10 to assess symptom validity in treatment-seeking OIF/OEF Veterans with a history of mTBI.