The Relationship Between Postconcussive Symptoms and Quality of Life in Veterans With Mild to Moderate Traumatic Brain Injury

Symptom Attribution and Neuropsychological Outcomes Among Treatment-Seeking Veterans With a History of Traumatic Brain Injury

OBJECTIVE

In this cross-sectional study, the authors aimed to examine relationships between illness perception, measured as symptom attribution, and neurobehavioral and neurocognitive outcomes among veterans with a history of traumatic brain injury (TBI).

METHODS

This study included 55 treatment-seeking veterans (N=43 with adequate performance validity testing) with a remote history of TBI (80% with mild TBI). Veterans completed a clinical interview, self-report questionnaires, and a neuropsychological assessment. A modified version of the Neurobehavioral Symptom Inventory (NSI) was administered to assess neurobehavioral symptom endorsement and symptom attribution. Composite scores were calculated from standardized cognitive tests to assess specific aspects of objective cognitive functioning, including memory, executive functioning, attention and working memory, and processing speed.

RESULTS

The symptoms most frequently attributed to TBI included forgetfulness, poor concentration, slowed thinking, and headaches. There was a significant positive association between symptom attribution and overall symptom endorsement (NSI total score) (r=0.675) and endorsement of specific symptom domains (NSI symptom domain scores) (r=0.506-0.674), indicating that greater attribution of symptoms to TBI was associated with greater symptom endorsement. Furthermore, linear regressions showed that symptom attribution was significantly associated with objective cognitive functioning, whereas symptom endorsement generally did not show this relationship. Specifically, greater attribution of symptoms to TBI was associated with worse executive functioning (β=-0.34), attention and working memory (β=-0.43), and processing speed (β=-0.35).

CONCLUSIONS

These findings suggest that veterans who routinely attribute neurobehavioral symptoms to their TBI are at greater risk of experiencing poor long-term outcomes, including elevated symptom endorsement and worse objective cognition. Although more research is needed to understand how illness perception influences outcomes in this population, these preliminary results highlight the importance of early psychoeducation regarding the anticipated course of recovery following TBI.

Randomized, controlled clinical trial of acoustic stimulation to reduce postconcussive symptoms

OBJECTIVE

Effective interventions are needed to address postconcussive symptoms. We report the results of randomized, sham-controlled trial of Cereset Research™ Standard Operating Procedures (CR-SOP), a noninvasive, closed-loop, allostatic, acoustic stimulation neurotechnology previously shown to improve insomnia.

METHODS

Military service members, veterans, or their spouses with persistent symptoms (Neurobehavioral Symptom Inventory [NSI] Score ≥23) after mTBI 3 months to 10 years ago, were randomized to receive 10 sessions of engineered tones linked to brainwaves (LB, intervention), or random engineered tones not linked to brainwaves (NL, sham control). The primary outcome was change in NSI, with secondary outcomes of heart rate variability and self-report measures of sleep, mood, and anxiety.

RESULTS

Participants (n = 106, 22% female, mean age 37.1, 2.8 deployments, 3.8 TBIs) were randomized 1:1 to LB or NL, with no significant differences between groups at baseline. Among all study participants, the NSI declined from baseline 41.0 to 27.2 after (P < 0.0001), with gains largely sustained at 3 months (31.2) and 6 months (28.4). However, there were no significant differences between the LB (NSI declined from 39.9 at baseline to 28.2 post-intervention, 31.5 at 3 months, and 29.4 at 6 months) and NL (NSI declined from 41.5 at baseline to 26.2, 29.9, and 27.3, respectively. Similar patterns were observed for the PCL5 and PHQ-9 and there was no difference in HRV between groups.

INTERPRETATION

Ten hours of acoustic stimulation while resting in a zero-gravity chair improves postconcussive symptoms. However, linking tones to brain electrical activity did not reduce symptoms more than random tones.

REGISTRATION

ClinicalTrials.gov - NCT03649958.

Exploring the relationship between sleep apnea and vestibular symptoms following traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) is a complex health problem in military veterans and service members (V/SM) that often involves comorbid vestibular impairment. Sleep apnea is another comorbidity that may exacerbate, and/or be exacerbated by, vestibular dysfunction.

OBJECTIVE

To examine the relationship between sleep apnea and vestibular symptoms in V/SM diagnosed with TBI of any severity.

DESIGN

Multicenter cohort study; cross-sectional sample.

SETTING

In-patient TBI rehabilitation units within five Veterans Affairs (VA) Polytrauma Rehabilitation Centers.

PARTICIPANTS

V/SM with a diagnosis of TBI (N = 630) enrolled in the VA TBI Model Systems study.

INTERVENTION

Not applicable.

METHODS

A multivariable regression model was used to evaluate the association between sleep apnea and vestibular symptom severity while controlling for relevant covariates, for example, posttraumatic stress disorder (PTSD).

MAIN OUTCOME MEASURES

Lifetime history of sleep apnea was determined via best source reporting. Vestibular disturbances were measured with the 3-item Vestibular subscale of the Neurobehavioral Symptom Inventory (NSI).

RESULTS

One third (30.6%) of the sample had a self-reported sleep apnea diagnosis. Initial analysis showed that participants who had sleep apnea had more severe vestibular symptoms (M = 3.84, SD = 2.86) than those without sleep apnea (M = 2.88, SD = 2.67, p < .001). However, when the data was analyzed via a multiple regression model, sleep apnea no longer reached the threshold of significance as a factor associated with vestibular symptoms. PTSD severity was shown to be significantly associated with vestibular symptoms within this sample (p < .001).

CONCLUSION

Analysis of these data revealed a relationship between sleep apnea and vestibular symptoms in V/SM with TBI. The significance of this relationship was affected when PTSD symptoms were factored into a multivariable regression model. However, given that the mechanisms and directionality of these relationships are not yet well understood, we assert that in terms of clinical relevance, providers should emphasize screening for each of the three studied comorbidities (sleep apnea, vestibular symptoms, and PTSD).

Baseline executive functioning moderates treatment-related changes in quality of life in veterans with posttraumatic stress disorder and comorbid traumatic brain injury

Posttraumatic stress disorder (PTSD) treatment has been associated with improvement in quality of life (QOL); however, little is known about factors that moderate treatment-related changes in QOL, particularly cognitive factors. Executive functioning (EF) is important for success across all aspects of everyday life and predicts better psychological and physical health. EF is important to QOL, but more work is needed to better understand the association between EF and QOL improvements following interventions. We hypothesized that poorer baseline EF would be associated with less improvement in overall life satisfaction and satisfaction with health following PTSD treatment. U.S. veterans who served after the September 11, 2001 terrorist attacks (post 9-11; N = 80) with PTSD and a history of mild-to-moderate traumatic brain injury were randomized to standard cognitive processing therapy (CPT) or CPT combined with cognitive rehabilitation (SMART-CPT). Multilevel modeling was used to examine whether baseline EF performance was associated with changes in QOL scores from pretreatment to follow-up across both groups. Results indicated that poorer baseline performance on EF tests of working memory and inhibition were associated with less treatment-related improvements in general life satisfaction and satisfaction with health, rs = .26-.36. Treatment condition did not moderate any results. Future research should examine whether implementing EF-focused techniques before and/or concurrently with CPT for individuals with poorer baseline working memory and inhibition enhances QOL treatment gains, particularly in terms of general life and health-related satisfaction.

Characterizing Sex Differences in Clinical and Functional Outcomes Among Military Veterans with a Comprehensive Traumatic Brain Injury Evaluation (CTBIE): A Million Veteran Program (MVP) Study

Using a diverse sample of military Veterans enrolled in the VA's Million Veteran Program (N=14,378; n=1,361 females [9.5%]; all previously deployed), we examined sex differences on the Comprehensive Traumatic Brain Injury Evaluation (CTBIE), a structured traumatic brain injury (TBI) interview routinely administered within the VA. Confirmed TBI diagnoses were more frequent among males than females (65% vs. 58%). Additionally, when compared to females, a greater proportion of males with CTBIE-confirmed TBI histories experienced blast-related injuries and were employed. In contrast, a greater proportion of females reported experiencing falls, sustaining a TBI since deployment, and having more severe neurobehavioral symptoms (particularly affective-related symptoms). Results indicate that males and females experience differential clinical and functional outcomes in the aftermath of military TBI. Findings underscore the need to increase female representation in TBI research to increase understanding of sex-specific experiences with TBI and to improve the clinical care targeted to this vulnerable population.

Neuropsychological Performance and Functional Capacity Following Mild Traumatic Brain Injury in Veterans

OBJECTIVE

To examine the relationship between neuropsychological functioning and performance-based functional capacity in veterans with a history of mild traumatic brain injury (mTBI), as well as the moderating effects of age and psychiatric symptoms on this relationship.

SETTING

Three Veterans Affairs medical centers.

PARTICIPANTS

One hundred nineteen Iraq/Afghanistan veterans with a history of mTBI and self-reported cognitive difficulties.

DESIGN

Cross-sectional, secondary data analysis of baseline measures in a randomized controlled trial.

MAIN MEASURES

The main outcome measure, functional capacity, was assessed using the objective and performance-based University of California San Diego Performance-based Skills Assessment-Brief. A global deficit score (GDS) was created as a composite score for performance on a battery of neuropsychological measures assessing domains of attention, processing speed, executive functioning, and verbal memory performance. Posttraumatic stress disorder (PTSD) symptom severity was assessed using the PTSD Checklist-Military Version, and depressive symptom severity was assessed using the Beck Depression Inventory, Second Edition.

RESULTS

Bivariate analyses indicated that worse neuropsychological performance (ie, higher GDS) and greater PTSD symptom severity were associated with worse communication abilities and worse overall functional capacity. Multiple linear regressions demonstrated that GDS and PTSD symptom severity explained 9% of the variance in communication and 10% of the variance in overall functional capacity; however, GDS emerged as the only significant predictor in both regressions. Age, PTSD, and depressive symptom severity did not moderate the relationship between GDS and overall functional capacity. Performance in the verbal learning and memory domain emerged as the strongest neuropsychological predictor of communication and overall functional capacity.

CONCLUSIONS

Worse neuropsychological functioning was moderately associated with worse performance-based functional capacity, even when accounting for PTSD symptom severity. Verbal learning and memory was the primary neuropsychological domain driving the relationship with functional capacity; improvement in verbal learning and memory may translate into improved functional capacity.

Postconcussion Symptoms After an Uncomplicated Mild Traumatic Brain Injury in Older Adults: Frequency, Risk Factors, and Impact on Quality of Life

BACKGROUND

Postconcussion symptoms (PCSs) are common complaints reported by patients after a mild traumatic brain injury (TBI), and these symptoms may lower quality of life. Previous investigations have primarily focused on PCSs in children, adults, and athletes. The frequency, and risk factors, and effects of PCSs for older adults with mild TBIs are unclear.

PURPOSE

To investigate the frequency and risk factors of PCSs, and investigate their effects on quality of life over time after mild TBI in older adults.

METHODS

A prospective longitudinal study was performed. All participants were enrolled from the emergency department or neurosurgical outpatient clinics of a medical center. The measurement tools were the Rivermead Post-Concussion Symptoms Questionnaire and the Quality of Life after Traumatic Brain Injury. Measurements were performed on the seventh day, at the first month, and at the sixth month after the head injury. A generalized estimating equation model was used for data analyses.

RESULTS

One hundred and one older adults (mean age of 76.0 years) with mild TBIs with negative neuroimaging findings were included. Overall, 32.7%, 4%, and 15.8% of the sample reported PCS after 7 days, 1 month, and 6 months of head injury, respectively, revealing a U-shaped trend. We observed that comorbidity measured using the modified Charlson Comorbidity Index was associated with differences in PCSs ( P < .05). PCSs were an independent predictor of changes in postinjury quality of life ( P < .001).

CONCLUSIONS

The results indicate that PCS after a mild TBI in older adults is prevalent, even in the chronic phase after a TBI, and PCSs significantly affected the quality of life of our cohort. Therefore, to improve patient quality of life, healthcare providers should employ effective interventions to manage PCSs at different phases after a TBI.

Racial and Socioeconomic Disparities in Neurotrauma: Research Priorities in the New York Metropolitan Area through a Global Neurosurgery Paradigm

The New York Neurotrauma Consortium (NYNC) is a nascent multidisciplinary research and advocacy organization based in the New York Metropolitan Area (NYMA). It aims to advance health equity and optimize outcomes for traumatic brain and spine injury patients. Given the extensive racial, ethnic, and socioeconomic diversity of the NYMA, global health frameworks aimed at eliminating disparities in neurotrauma may provide a relevant and useful model for the informing research agendas of consortia like the NYNC. In this review, we present a comparative analysis of key health disparities in traumatic brain injury (TBI) that persist in the NYMA as well as in low- and middle-income countries (LMIC). Examples include: (a) inequitable access to quality care due to fragmentation of healthcare systems, (b) barriers to effective prehospital care for TBI, and (c) socioeconomic challenges faced by patients and their families during the subacute and chronic post-injury phases of TBI care. This review presents strategies to address each area of health disparity based on previous studies conducted in both LMIC and high-income country (HIC) settings. Increased awareness of healthcare disparities, education of healthcare professionals, effective policy advocacy for systemic changes, and fostering racial diversity of the trauma care workforce can guide the development of trauma care systems in the NYMA that are free of racial and related healthcare disparities.

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.

Elevated Neuropsychological Intraindividual Variability Predicts Poorer Health-Related Quality of Life in Veterans with a History of Mild Traumatic Brain Injury

We examined the association between cognitive functioning and health-related quality of life (HR-QOL) in military veterans with a history of mild traumatic brain injury (mTBI) using two methods to assess cognition: mean performance on cognitive composite scores and across-test intraindividual variability (IIV). The sample included 73 veterans (84.9% male; age, mean = 32.47 years) who completed neuropsychological testing and self-report questionnaires ∼7 years post-injury. Three cognitive composite scores representing mean performance were computed, including memory, attention/processing speed (A/PS), and executive functioning (EF). Three IIV indices were also calculated reflecting degree of dispersion across the same cognitive domains: memory-IIV, A/PS-IIV, and EF-IIV. The Posttraumatic Stress Disorder (PTSD) Checklist-Military Version (PCL-M) was used to assess current PTSD symptoms, and the World Health Organization Quality of Life Short Version Physical Health domain was used to assess HR-QOL. Hierarchical linear regressions adjusting for PTSD symptoms demonstrated that IIV indices, but not mean cognitive composite scores, significantly predicted HR-QOL. Specifically, memory-IIV, A/PS-IIV, and EF-IIV, when taken together, made an independent and significant contribution to the prediction of HR-QOL. Examination of the standardized coefficients showed that the A/PS-IIV index was uniquely associated with HR-QOL, such that higher A/PS-IIV scores significantly predicted poorer HR-QOL. Our results are the first to show that, in veterans with remote mTBI histories, greater fluctuations in cognitive performance significantly contribute to poorer HR-QOL, even after accounting for PTSD symptom severity. Moreover, findings suggest that, compared to traditional mean cognitive performance scores, measures of IIV may represent more sensitive indicators of clinical outcome and better align with subjective experiences of distress.

Mental and physical health, and long-term quality of life among service members injured on deployment

Background

More than 52,000 casualties have been documented in post-9/11 conflicts. Service members with extremity injuries (EIs) or traumatic brain injury (TBI) may be at particular risk for long-term deficits in mental and physical health functioning compared with service members with other injuries.

Methods

The present study combined medical records with patient reports of mental health and health-related quality of life (HRQOL) for 2,537 service members injured in overseas contingency operations who participated in the Wounded Warrior Recovery Project. Combined parallel-serial mediation models were tested to examine the pathways through which injury is related to mental and physical health conditions, and long-term HRQOL.

Results

Results revealed that injury was indirectly related to long-term HRQOL via its associations with physical health complications and mental health symptoms. Relative to TBI, EI was associated with a higher likelihood for a postinjury diagnosis for a musculoskeletal condition, which were related to lower levels of later posttraumatic stress disorder (PTSD) symptoms, and higher levels of physical and mental HRQOL. Similarly, EI was related to a lower likelihood for a postinjury PTSD diagnosis, and lower levels of subsequent PTSD symptoms, and therefore higher physical and mental HRQOL relative to those with TBI. Despite this, the prevalence of probable PTSD among those with EI was high (35%). Implications for intervention, rehabilitation, and future research are discussed.

Network Analysis of Research on Mild Traumatic Brain Injury in US Military Service Members and Veterans During the Past Decade (2010-2019)

OBJECTIVE

To evaluate trends in the extant literature on mild traumatic brain injury (mTBI) in military service members and veterans using network analysis based on a comprehensive search of original, peer-reviewed research articles involving human participants published between January 1, 2010, and December 31, 2019. Specifically, we employed network analysis to evaluate associations in the following areas: (1) peer-reviewed journals, (2) authors, (3) organizations/institutions, and (4) relevant key words.

PARTICIPANTS

Included studies were published in peer-reviewed journals available on Web of Science database, using US military service members or veterans.

DESIGN

Bibliometric network analytical review.

MAIN MEASURES

Outcomes for each analysis included number of articles, citations, total link strength, and clusters.

RESULTS

The top publishing journals were (1) Journal of Head Trauma and Rehabilitation, (2) Military Medicine, (3) Brain Injury, (4) Journal of Neurotrauma, and (5) Journal of Rehabilitation Research and Development. The top publishing authors were (1) French, (2) Lange, (3) Cooper, (4) Vanderploeg, and (5) Brickell. The top research institutions were (1) Defense and Veterans Brain Injury Center, (2) Uniformed Services University of the Health Sciences, (3) University of California San Diego, (4) Walter Reed National Military Medical Center, and (5) Boston University. The top co-occurring key words in this analysis were (1) posttraumatic stress disorder (PTSD), (2) persistent postconcussion symptoms (PPCS), (3) blast injury, (4) postconcussion syndrome (PCS), and (5) Alzheimer's disease.

CONCLUSIONS

The results of this network analysis indicate a clear focus on veteran health, as well as investigations on chronic effects of mTBI. Research in civilian mTBI indicates that delaying treatment for symptoms and impairments related to mTBI may not be the most precise treatment strategy. Increasing the number of early, active, and targeted treatment trials in military personnel could translate to meaningful improvements in clinical practices for managing mTBI in this population.

Relationship between depression, community integration and life satisfaction following mild traumatic brain injury

Purpose: Compared to studies on moderate and severe traumatic brain injury (TBI), less literature exists concerning the consequences of mild traumatic brain injury (mTBI) on community integration and life satisfaction, especially in the early phase of recovery. Moreover, a better understanding of the variables that contribute to community integration and life satisfaction is still needed. The aim of the study was to assess the association of mood, fatigue and post-concussive symptoms with community integration and life satisfaction early following mTBI.Research method: A total of 85 participants aged between 18 and 61 years who sustained mTBI were included. Participants answered web-based questionnaires measuring anxiety and depression symptoms, fatigue, post-concussive symptoms, community integration and life satisfaction in the first three months post mTBI.Results: Post-concussive symptoms, fatigue and anxiety were not associated with community integration or life satisfaction. However, depressive symptoms were negatively associated with community integration and life satisfaction.Conclusions: Among all acute post-concussive symptoms following mTBI, depressive symptoms seem to have strongest relationship with community integration and life satisfaction. Acute psychological intervention targeting these symptoms is strongly recommended.

Factors Associated with Quality of Life in Adults with Persistent Post-Concussion Symptoms

OBJECTIVE

To assess demographic, clinical, and injury characteristics associated with health-related quality of life (HRQOL) in adults with persistent post-concussion symptoms (PPCS).

METHODS

Adults with PPCS presenting to a specialized brain injury clinic completed demographic, injury, and clinical outcome questionnaires at the initial clinic assessment. Clinical outcome measures were collected including the Rivermead Post-Concussion Symptoms Questionnaire (RPQ), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder Scale-7 (GAD-7), and the Fatigue Severity Scale (FSS). HRQOL was measured using the Quality of Life after Brain Injury (QOLIBRI) questionnaire. Stepwise hierarchical multiple regression analysis adjusting for age, sex, and months since injury was used to determine associations between quality of life and clinical outcome measures.

RESULTS

Overall, 125 participants were included. The PHQ-9, FSS, and GAD-7 were significant predictors of QOLIBRI scores (R2 = 0.481, p < .001), indicating that participants with higher levels of depressive symptoms, fatigue, and anxiety reported poorer HRQOL. The PHQ-9 score was the strongest predictor, accounting for 42.0% of the variance in QOLIBRI scores. No demographic or injury characteristics significantly predicted QOLIBRI scores. There was a high prevalence of depressive symptoms with 72.8% of participants having PHQ-9 scores ≥ 10.

CONCLUSION

Among patients with PPCS, mental health and fatigue are important contributors to HRQOL. As there is a high burden of mood disorders and fatigue in this population, targeted treatments for these concerns may impact the quality of life.

Repetitive mTBI is associated with age-related reductions in cerebral blood flow but not cortical thickness

Mild traumatic brain injury (mTBI) is a risk factor for Alzheimer's disease (AD), and evidence suggests cerebrovascular dysregulation initiates deleterious neurodegenerative cascades. We examined whether mTBI history alters cerebral blood flow (CBF) and cortical thickness in regions vulnerable to early AD-related changes. Seventy-four young to middle-aged Veterans (mean age = 34, range = 23-48) underwent brain scans. Participants were divided into: (1) Veteran Controls (n = 27), (2) 1-2 mTBIs (n = 26), and (2) 3+ mTBIs (n = 21) groups. Resting CBF was measured using MP-PCASL. T1 structural scans were processed with FreeSurfer. CBF and cortical thickness estimates were extracted from nine AD-vulnerable regions. Regression analyses examined whether mTBI moderated the association between age, CBF, and cortical thickness. Regressions adjusting for sex and posttraumatic stress revealed mTBI moderated the association between age and CBF of the precuneus as well as superior and inferior parietal cortices (p's < .05); increasing age was associated with lower CBF in the 3+ mTBIs group, but not in the VCs or 1-2 mTBIs groups. mTBI did not moderate associations between age and cortical thickness (p's >.05). Repetitive mTBI is associated with cerebrovascular dysfunction in AD-vulnerable regions and may accelerate pathological aging trajectories.

Objective Dual-Task Turning Measures for Return-to-Duty Assessment After Mild Traumatic Brain Injury: The ReTURN Study Protocol

Determining readiness for duty after mild traumatic brain injury (mTBI) is essential for the safety of service members and their unit. Currently, these decisions are primarily based on self-reported symptoms, objective measures that assess a single system, or standardized physical or cognitive tests that may be insensitive or lack ecological validity for warrior tasks. While significant technological advancements have been made in a variety of assessments of these individual systems, assessments of isolated tasks are neither diagnostically accurate nor representative of the demands imposed by daily life and military activities. Emerging evidence suggests that complex tasks, such as dual-task paradigms or turning, have utility in probing functional deficits after mTBI. Objective measures from turning tasks in single- or dual-task conditions, therefore, may be highly valuable for clinical assessments and return-to-duty decisions after mTBI. The goals of this study are to assess the diagnostic accuracy, predictive capacity, and responsiveness to rehabilitation of objective, dual-task turning measures within an mTBI population. These goals will be accomplished over two phases. Phase 1 will enroll civilians at three sites and active-duty service members at one site to examine the diagnostic accuracy and predictive capacity of dual-task turning outcomes. Phase 1 participants will complete a series of turning tasks while wearing inertial sensors and a battery of clinical questionnaires, neurocognitive testing, and standard clinical assessments of function. Phase 2 will enroll active-duty service members referred for rehabilitation from two military medical treatment facilities to investigate the responsiveness to rehabilitation of objective dual-task turning measures. Phase 2 participants will complete two assessments of turning while wearing inertial sensors: a baseline assessment prior to the first rehabilitation session and a post-rehabilitation assessment after the physical therapist determines the participant has completed his/her rehabilitation course. A variable selection procedure will then be implemented to determine the best task and outcome measure for return-to-duty decisions based on diagnostic accuracy, predictive capacity, and responsiveness to rehabilitation. Overall, the results of this study will provide guidance and potential new tools for clinical decisions in individuals with mTBI.

Clinical Trial Registration: clinicaltrials.gov, Identifier NCT03892291.

Gait Performance in People with Symptomatic, Chronic Mild Traumatic Brain Injury

There is a dearth of knowledge about how symptom severity affects gait in the chronic (>3 months) mild traumatic brain injury (mTBI) population despite up to 53% of people reporting persisting symptoms after mTBI. The aim of this investigation was to determine whether gait is affected in a symptomatic, chronic mTBI group and to assess the relationship between gait performance and symptom severity on the Neurobehavioral Symptom Inventory (NSI). Gait was assessed under single- and dual-task conditions using five inertial sensors in 57 control subjects and 65 persons with chronic mTBI (1.0 year from mTBI). The single- and dual-task gait domains of Pace, Rhythm, Variability, and Turning were calculated from individual gait characteristics. Dual-task cost (DTC) was calculated for each domain. The mTBI group walked (domain z-score mean difference, single-task = 0.70; dual-task = 0.71) and turned (z-score mean difference, single-task = 0.69; dual-task = 0.70) slower (p < 0.001) under both gait conditions, with less rhythm under dual-task gait (z-score difference = 0.21; p = 0.001). DTC was not different between groups. Higher NSI somatic subscore was related to higher single- and dual-task gait variability as well as slower dual-task pace and turning (p < 0.01). Persons with chronic mTBI and persistent symptoms exhibited altered gait, particularly under dual-task, and worse gait performance related to greater symptom severity. Future gait research in chronic mTBI should assess the possible underlying physiological mechanisms for persistent symptoms and gait deficits.

Long-term negative emotional outcomes of warzone TBI

OBJECTIVE

Many veterans of the Iraq and Afghanistan Wars have experienced traumatic brain injury (TBI). Although prior work has examined associations between TBI and development of psychiatric syndromes, less is known about associations between TBI and component emotions constituting these syndromes, especially in the long term. The purpose of this study was to examine the long-term emotional consequences of deployment-related TBI.

METHODS

As part of VA Cooperative Studies Program #566, we assessed a sample of n = 456 US Army soldiers prior to an index deployment to Iraq, and again an average of 8.3 years (SD = 2.4 years) after their deployment for a long-term follow-up assessment. In this report, we used adjusted regression analyses to examine the relationship of deployment TBI to depression, anxiety, and stress symptom severity measured at the long-term follow-up assessment. A structured interview was used to determine TBI history; the Depression, Anxiety, and Stress Scale, 21-item version (DASS-21) was used to determine emotional status at the follow-up evaluation.

RESULTS

Warzone TBI events, particularly when greater than mild in severity, were independently associated with depression, anxiety, and stress severity at long-term follow-up, even after taking into account variance attributable to pre-deployment emotional distress and war-zone stress. Post-hoc analyses did not detect independent associations of either number of events or injury mechanism with outcomes.

CONCLUSIONS

These findings highlight the potentially enduring and multi-faceted emotional effects of deployment TBI, underscoring the need for early assessment of negative affectivity in warzone veterans reporting TBI.

Fatigue Is Associated With Global and Regional Thalamic Morphometry in Veterans With a History of Mild Traumatic Brain Injury

OBJECTIVE

Fatigue is a complex, multidimensional phenomenon that commonly occurs following traumatic brain injury (TBI). The thalamus-a structure vulnerable to both primary and secondary injuries in TBI-is thought to play a pivotal role in the manifestation of fatigue. We explored how neuroimaging markers of local and global thalamic morphometry relate to the subjective experience of fatigue post-TBI.

METHODS

Sixty-three Veterans with a history of mild TBI underwent structural magnetic resonance imaging and completed questionnaires related to fatigue and psychiatric symptoms. FMRIB's Software (FSL) was utilized to obtain whole brain and thalamic volume estimates, as well as to perform regional thalamic morphometry analyses.

RESULTS

Independent of age, sex, intracranial volume, posttraumatic stress disorder, and depressive symptoms, greater levels of self-reported fatigue were significantly associated with decreased right (P = .026) and left (P = .046) thalamic volumes. Regional morphometry analyses revealed that fatigue was significantly associated with reductions in the anterior and dorsomedial aspects of the right thalamic body (P < .05). Similar trends were observed for the left thalamic body (P < .10).

CONCLUSIONS

Both global and regional thalamic morphometric changes are associated with the subjective experience of fatigue in Veterans with a history of mild TBI. These findings support a theory in which disruption of thalamocorticostriatal circuitry may result in the manifestation of fatigue in individuals with a history of neurotrauma.

Risk of Posttraumatic Stress Disorder and Major Depression in Civilian Patients After Mild Traumatic Brain Injury: A TRACK-TBI Study

IMPORTANCE

Traumatic brain injury (TBI) has been associated with adverse mental health outcomes, such as posttraumatic stress disorder (PTSD) and major depressive disorder (MDD), but little is known about factors that modify risk for these psychiatric sequelae, particularly in the civilian sector.

OBJECTIVE

To ascertain prevalence of and risk factors for PTSD and MDD among patients evaluated in the emergency department for mild TBI (mTBI).

DESIGN, SETTING, AND PARTICIPANTS

Prospective longitudinal cohort study (February 2014 to May 2018). Posttraumatic stress disorder and MDD symptoms were assessed using the PTSD Checklist for DSM-5 and the Patient Health Questionnaire-9 Item. Risk factors evaluated included preinjury and injury characteristics. Propensity score weights-adjusted multivariable logistic regression models were performed to assess associations with PTSD and MDD. A total of 1155 patients with mTBI (Glasgow Coma Scale score, 13-15) and 230 patients with nonhead orthopedic trauma injuries 17 years and older seen in 11 US hospitals with level 1 trauma centers were included in this study.

MAIN OUTCOMES AND MEASURES

Probable PTSD (PTSD Checklist for DSM-5 score, ≥33) and MDD (Patient Health Questionnaire-9 Item score, ≥15) at 3, 6, and 12 months postinjury.

RESULTS

Participants were 1155 patients (752 men [65.1%]; mean [SD] age, 40.5 [17.2] years) with mTBI and 230 patients (155 men [67.4%]; mean [SD] age, 40.4 [15.6] years) with nonhead orthopedic trauma injuries. Weights-adjusted prevalence of PTSD and/or MDD in the mTBI vs orthopedic trauma comparison groups at 3 months was 20.0% (SE, 1.4%) vs 8.7% (SE, 2.2%) (P < .001) and at 6 months was 21.2% (SE, 1.5%) vs 12.1% (SE, 3.2%) (P = .03). Risk factors for probable PTSD at 6 months after mTBI included less education (adjusted odds ratio, 0.89; 95% CI, 0.82-0.97 per year), being black (adjusted odds ratio, 5.11; 95% CI, 2.89-9.05), self-reported psychiatric history (adjusted odds ratio, 3.57; 95% CI, 2.09-6.09), and injury resulting from assault or other violence (adjusted odds ratio, 3.43; 95% CI, 1.56-7.54). Risk factors for probable MDD after mTBI were similar with the exception that cause of injury was not associated with increased risk.

CONCLUSIONS AND RELEVANCE

After mTBI, some individuals, on the basis of education, race/ethnicity, history of mental health problems, and cause of injury were at substantially increased risk of PTSD and/or MDD. These findings should influence recognition of at-risk individuals and inform efforts at surveillance, follow-up, and intervention.

Associations between neuropsychiatric and health status outcomes in individuals with probable mTBI

Mild traumatic brain injury (mTBI) is a common occurrence, and may impact distal outcomes in a subgroup of individuals. Improved characterization of health outcomes and identification of factors associated with poor outcomes is needed to better understand the impact of mTBI, particularly in those with co-occurring posttraumatic stress disorder (PTSD). Participants in a data repository of the Injury and Traumatic Stress (INTRuST) Clinical Consortium (n = 625) completed functional disability [FD] and health-related quality of life [HRQOL] questionnaires, and a subset completed a neuropsychological assessment. FD and HRQOL were compared among participants with probable mTBI (mTBI), probable mTBI with PTSD (mTBI/PTSD), and health comparison participants (HC). Associations between symptoms, neuropsychological performance, and health outcomes were examined in those with probable mTBI with and without PTSD (n = 316). Individuals in the mTBI/PTSD group endorsed poorer health outcomes than those in the mTBI group, who endorsed poorer outcomes than those in the HC group. Individuals in either mTBI group performed worse than those in the HC on verbal learning and memory and psychomotor speed. Health outcomes were correlated with mental health and postconcussive symptoms, as well as neuropsychological variables. mTBI may adversely impact self-reported health, with the greatest effect observed in individuals with co-occurring mTBI/PTSD.

Postconcussive symptoms (PCS) following combat-related traumatic brain injury (TBI) in Veterans with posttraumatic stress disorder (PTSD): Influence of TBI, PTSD, and depression on symptoms measured by the Neurobehavioral Symptom Inventory (NSI)

Mild traumatic brain injury (mTBI) is commonly reported in recent combat Veterans. While the majority resolve, some Veterans develop postconcussive symptoms (PCS). Previous research suggests these symptoms are not specific to head injury and are often associated with psychiatric symptoms. The current study examines the relative contributions of posttraumatic stress, depressive symptoms, and TBI on postconcussive symptoms, and explores whether the relationship remains after controlling for symptom overlap. Two hundred eighteen combat Veterans from Operation Iraqi Freedom (OIF), Operation Enduring Freedom (OEF), and Operation New Dawn (OND) provided the data for this study as part of a baseline evaluation for inclusion into larger treatment study for posttraumatic stress disorder (PTSD). Participants completed the Brief Traumatic Brain Injury Screen (BTBIS), Neurobehavioral Symptom Inventory (NSI), PTSD Checklist-Stressor Version (PCL-S), Beck Depression Inventory-II (BDI-II). Significant differences in NSI total score between individuals with and without history of TBI were not found. A series of regression analyses demonstrated that Depression and PTSD were significant predictors of NSI score even after removal of NSI symptoms that overlap with PTSD or depression. TBI status was also a significant predictor of PCS in most models, but its relative contribution was much smaller than that of depression and PTSD. Within PTSD symptoms, hyperarousal cluster was a significant predictor of NSI scores. Findings demonstrate that depression and PTSD are related to PCS beyond similarities in construct. Further, within a primarily PTSD treatment-seeking population, these psychiatric symptoms appear to be a stronger contributor than TBI.

Cognitive fatigue is associated with reduced anterior internal capsule integrity in veterans with history of mild to moderate traumatic brain injury

No known studies have directly examined white matter microstructural correlates of cognitive fatigue post-TBI in a Veteran sample. We therefore investigated the relationship between cognitive fatigue and white matter integrity in Veterans with history of mild to moderate TBI (mmTBI). 59 Veterans (TBI = 34, Veteran Controls [VCs] = 25]) with and without history of mmTBI underwent structural 3T DTI scans and completed questionnaires related to cognitive fatigue and psychiatric symptoms. Tractography was employed on six regions of interest, including the anterior and posterior limbs of the internal capsule; genu; body and splenium of the corpus callosum; and cingulum bundle. Group analyses revealed that those with history of mmTBI displayed significantly greater levels of cognitive fatigue relative to those with no history of head injury (p = .02). Within the mmTBI group, independent of psychiatric symptoms, decreased white matter microstructural integrity of the left anterior internal capsule was associated with greater levels of cognitive fatigue (p = .01). Results show that the subjective experience of cognitive fatigue following neurotrauma may be linked to the disruption of striato-thalamo-cortical tracts that are important in mediating arousal and higher-order cognitive processes. These findings build upon those from existing functional neuroimaging studies in those with history of TBI, providing further evidence for the neural basis of cognitive fatigue in head injured adults.

Abnormal Turning and Its Association with Self-Reported Symptoms in Chronic Mild Traumatic Brain Injury

Turning is common in daily activity and requires rapid, coordinated reorientation of the head, trunk, and pelvis toward the new direction of travel. Yet, turning gait has not been well explored in populations with mild traumatic brain injury (mTBI) who may alter their turning behavior according to self-perceived symptoms or motor dysfunction. The purpose of this study was to examine turning velocities and coordination in adults with chronic mTBI (>3 months post-injury and still reporting balance complaints) during a task simulating everyday ambulation. We hypothesized that individuals with chronic mTBI would reduce their angular velocity when turning and increase the variability of head-pelvis coordination compared with controls, and that the reduction in velocity and increased variability would be associated with their self-reported symptom score. Forty-two adults (14 chronic mTBI, 28 controls) completed the Neurobehavioral Symptom Inventory before walking 12 laps around a marked course containing two 45-degree turns, four 90-degree turns, and two 135-degree turns. Inertial sensors collected angular velocities of the head and pelvis. After adjusting for covariates, participants with chronic mTBI had significantly slower lap times and peak angular velocities of the pelvis (p < 0.01) compared with the control group. The peak velocity timing (PVT) between peak velocities of the head and pelvis, and the variability of that timing was significantly greater in participants with chronic mTBI (p < 0.01). Within the chronic mTBI group, somatosensory symptoms were associated with slower angular velocities of the head and pelvis (p = 0.03) and increased PVT variability (p < 0.01). The results suggest individuals with chronic mTBI with worse somatic symptoms have impaired head stabilization during turning in situations similar to everyday life. These results encourage future research on turning gait to examine the causal relationship between symptoms and daily locomotor function in adults with chronic mTBI.

Prognostic Value of S-100β Protein for Prediction of Post-Concussion Symptoms after a Mild Traumatic Brain Injury: Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to determine the prognostic value of S-100β protein to identify patients with post-concussion symptoms after a mild traumatic brain injury (mTBI). A search strategy was submitted to seven databases from their inception to October 2016. Individual patient data were requested. Cohort studies evaluating the association between S-100β protein level and post-concussion symptoms assessed at least seven days after the mTBI were considered. Outcomes were dichotomized as persistent (≥3 months) or early (≥7 days <3 months). Our search strategy yielded 23,298 citations of which 29 studies including between seven and 223 patients (n = 2505) were included. Post-concussion syndrome (PCS) (16 studies) and neuropsychological symptoms (9 studies) were the most frequently assessed outcomes. The odds of having persistent PCS (odds ratio [OR] 0.62, 95% confidence interval [CI]: 0.34-1.12, p = 0.11, I² 0% [n = five studies]) in patients with an elevated S-100β protein serum level were not significantly different from those of patients with normal values while the odds of having early PCS (OR 1.67, 95% CI: 0.98-2.85, p = 0.06, I² 38% [n = five studies]) were close to statistical significance. Similarly, having an elevated S-100β protein serum level was not associated with the odds of returning to work at six months (OR 2.31, 95% CI: 0.50-10.64, p = 0.28, I² 22% [n = two studies]). Overall risk of bias was considered moderate. Results suggest that the prognostic biomarker S-100β protein has a low clinical value to identify patients at risk of persistent post-concussion symptoms. Variability in injury to S-100ß protein sample time, mTBI populations, and outcomes assessed could potentially explain the lack of association and needs further evaluation.

Hyperarousal Symptoms Explain the Relationship Between Cognitive Complaints and Working Memory Performance in Veterans Seeking PTSD Treatment

OBJECTIVE

Comorbidity and symptom overlap between traumatic brain injury and posttraumatic stress disorder (PTSD) in veterans returning from deployment present challenges with respect to differential diagnosis and treatment. Both conditions frequently manifest with attention and working memory deficits, though the underlying neuropsychological basis differs. This study evaluated whether hyperarousal symptoms explain the relationship between subjective and objective measures of cognition in a veteran sample.

PARTICIPANTS AND PROCEDURES

One-hundred three veterans completed the military version of the PTSD Checklist (PCL), the Neurobehavioral Symptom Inventory, and the Wechsler Memory Scale, 3rd edition digit span task with adequate effort.

RESULTS

Hierarchical regression suggested that hyperarousal, but not other PTSD symptoms, explained the relationship between neurobehavioral symptoms and cognitive functioning. This relationship was present regardless of whether veterans met full PTSD diagnostic criteria or screened positive on a traumatic brain injury screener and was robust to other moderators.

CONCLUSION

These findings highlight the importance of considering traumatic brain injury and PTSD symptom overlap, particularly the relationship between hyperarousal symptoms and attention and working memory deficits, in conceptualizing cases and treatment planning.

Dynamic association between perfusion and white matter integrity across time since injury in Veterans with history of TBI

OBJECTIVE

Cerebral blood flow (CBF) plays a critical role in the maintenance of neuronal integrity, and CBF alterations have been linked to deleterious white matter changes. Although both CBF and white matter microstructural alterations have been observed within the context of traumatic brain injury (TBI), the degree to which these pathological changes relate to one another and whether this association is altered by time since injury have not been examined. The current study therefore sought to clarify associations between resting CBF and white matter microstructure post-TBI.

METHODS

37 veterans with history of mild or moderate TBI (mmTBI) underwent neuroimaging and completed health and psychiatric symptom questionnaires. Resting CBF was measured with multiphase pseudocontinuous arterial spin labeling (MPPCASL), and white matter microstructural integrity was measured with diffusion tensor imaging (DTI). The cingulate cortex and cingulum bundle were selected as a priori regions of interest for the ASL and DTI data, respectively, given the known vulnerability of these regions to TBI.

RESULTS

Regression analyses controlling for age, sex, and posttraumatic stress disorder (PTSD) symptoms revealed a significant time since injury × resting CBF interaction for the left cingulum (p < 0.005). Decreased CBF was significantly associated with reduced cingulum fractional anisotropy (FA) in the chronic phase; however, no such association was observed for participants with less remote TBI.

CONCLUSIONS

Our results showed that reduced CBF was associated with poorer white matter integrity in those who were further removed from their brain injury. Findings provide preliminary evidence of a possible dynamic association between CBF and white matter microstructure that warrants additional consideration within the context of the negative long-term clinical outcomes frequently observed in those with history of TBI. Additional cross-disciplinary studies integrating multiple imaging modalities (e.g., DTI, ASL) and refined neuropsychiatric assessment are needed to better understand the nature, temporal course, and dynamic association between brain changes and clinical outcomes post-injury.

Predictors of cognitive and physical fatigue in post-acute mild-moderate traumatic brain injury

Post-traumatic fatigue (PTF) is a common, disabling, and often chronic symptom following traumatic brain injury (TBI). Yet, the impact of chronic cognitive and physical fatigue and their associations with psychiatric, sleep, cognitive, and psychosocial sequelae in mild-moderate TBI remain poorly understood. Sixty Veterans with a history of mild-moderate TBI and 40 Veteran controls (VC) were administered the Modified Fatigue Impact Scale, a validated measure of TBI-related cognitive and physical fatigue as well as measures of neuropsychiatric, psychosocial, sleep, and objective cognitive functioning. Compared to VC, TBI Veterans endorsed significantly greater levels of cognitive and physical fatigue. In TBI, psychiatric symptoms, sleep disturbance, and post-traumatic amnesia (PTA) were associated with both cognitive and physical fatigue, while loss of consciousness (LOC) and poor attention/processing speed were related to elevations in cognitive fatigue only. In regression analyses, anxiety, sleep disturbance, and LOC significantly predicted cognitive fatigue, while only post-traumatic stress symptoms and PTA contributed to physical fatigue. Cognitive and physical fatigue are problematic symptoms following mild-moderate TBI that are differentially associated with specific injury and psychiatric sequelae. Findings provide potential symptom targets for interventions aimed at ameliorating fatigue, and further underscore the importance of assessing and treating fatigue as a multi-dimensional symptom following TBI.

Mild Traumatic Brain Injury, PTSD, and Psychosocial Functioning Among Male and Female U.S. OEF/OIF Veterans

This study examined the unique and combined relationship between mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) with psychosocial functioning in a cohort of 1,312 U.S. male and female veterans of Operations Enduring Freedom (OEF) and Iraqi Freedom (OIF) enrolled in the Veterans After-Discharge Longitudinal Registry (Project VALOR). We assessed mTBI with structured screening questions reflective of current TBI classification standards and PTSD via the SCID-IV PTSD module; all other variables were assessed by self-report questionnaires. We identified significant diagnostic group differences in psychosocial functioning for both sexes. Individuals with PTSD, with or without a history of mTBI, reported significantly worse psychosocial functioning than individuals with mTBI alone or neither mTBI nor PTSD (males, η(2) p = .11, p < .001; females, η(2) p = .14, p < .001), even after adjusting for demographics and severity of chronic pain. The results suggested that veterans experiencing PTSD, regardless of whether they had a history of mTBI, were at increased risk for long-term psychosocial impairment. Further research examining possible benefits from improved access to resources and treatment to address these needs would be valuable.

Trajectories and associated factors of quality of life, global outcome, and post-concussion symptoms in the first year following mild traumatic brain injury

PURPOSE

To investigate the associated factors and change trajectories of quality of life (QoL), global outcome, and post-concussion symptoms (PCS) over the first year following mild traumatic brain injury (mTBI).

METHODS

This was a prospective longitudinal study of 100 participants with mTBI from neurosurgical outpatient departments in Chiayi County District Hospitals in Taiwan. The checklist of post-concussion syndromes (CPCS) was used to assess PCS at enrollment and at 1, 3, and 12 months after mTBI; the glasgow outcome scale extended (GOSE), the quality of life after brain injured (QOLIBRI), Chinese version, and the Short Form 36 Health Survey (SF-36), Taiwan version, were used to assess mTBI global outcome and QoL at 1, 3, and 12 months after mTBI.

RESULTS

Latent class growth models (LCGMs) indicated the change trajectories of QOLIBRI, PCS SF-36, MCS SF-36, GOSE, and PCS. Classes of trajectory were associated with age ≥40 years, unemployment at 1 month after injury, and educational level ≤12 years. Univariate analysis revealed that employment status at 1 month post-injury was correlated with the trajectories of QOLIBRI, PCS SF-36, MCS SF-36, and GOSE, but not PCS.

CONCLUSIONS

Employment status was the most crucial associated factor for QoL in individuals with mTBI at the 1-year follow-up. Future studies should explore the benefits of employment on QoL of individuals with mTBI.