A controlled prospective inception cohort study on the post-concussion syndrome outside the medicolegal context

Headache management in traumatic brain injury

Traumatic brain injury (TBI) is estimated to rank as the third most important disease burden worldwide. About 60% of the survivors develop chronic headaches and visual symptoms, and the long-term management of headaches in these patients is controversial. Importantly, the care pathway of most patients is fragmented, complicating conclusive headache management. Here we review the epidemiology and aetiology of post traumatic headaches (PTH), discuss the diagnostic work up and summarise the acute and long-term management.

The Postconcussion Syndrome and Posttraumatic Headaches in Civilians, Soldiers, and Athletes

Posttraumatic headaches are one of the most common and controversial secondary headache types. After a mild traumatic brain, an estimated 11% to 82% of people develop a postconcussion syndrome, which has been controversial for more than 160 years. Headache is estimated as present in 30% to 90% of patients after a mild head injury. Most headaches are tension-type-like or migraine-like. Headaches in civilians, soldiers, athletes, and postcraniotomy are reviewed. The treatments are the same as for the primary headaches. Persistent posttraumatic headaches can continue for many years.

Effects of repetitive mild traumatic brain injury on weight gain and chronic behavioral outcomes in male rats

To assess the long-term behavioral effects of repetitive mild traumatic brain injury (rmTBI), we employed a preclinical model of rmTBI and performed a battery of behavioral tests starting 14 weeks post-injury. Male Sprague-Dawley rats received four unilateral mild (6 m/s; 0.5 mm depth) controlled cortical impacts (CCI), centered 4 mm posterior and 3-4 mm lateral to the bregma, administered at five-day intervals. The animals' weights were monitored throughout the study. We tested the rats for anxiety-like (elevated plus maze, open field test), depression-like (forced swim test), locomotor (rotarod, open field test), and spatial learning and memory (Morris water maze (MWM)) behavioral deficits. Overall, a mild behavioral phenotype was observed. Significant deficits were observed with the MWM, indicating that our injury model disrupts spatial learning and memory. An interesting aspect of these data is a directional/visual component to the spatial learning and memory deficits dependent on the zone in which the trial began. With the injury being unilateral, there may be an imbalance in visual acuity that contributes to the observed deficits. Analysis of weight gain data demonstrated that rmTBI reduces weight during the period while injuries are occurring. This may represent another measure that can be tracked to determine injury severity and recovery. RNA-seq analysis demonstrated that gene expression at the chronic endpoint could distinguish between the experimental groups even with a mild behavioral phenotype. Future studies would include a more severe injury paradigm to promote longer-lasting behavior changes.

Position Paper on Post-Traumatic Headache: The Relationship Between Head Trauma, Stress Disorder, and Migraine

Traumatic brain injury (mTBI) is a major public health concern, with mild TBI (mTBI) constituting the vast majority of the injuries. Post-traumatic headache (PTH) is one of the most frequent symptoms that follow a mTBI, occurring in isolation with a tension-type or migraine phenotype, or more often as part of a complex neurobehavioural array of symptoms. The existence of PTH as a separate entity from the primary headaches is still a matter of debate. Classification issues and a lack of methodologically robust epidemiological and clinical studies have made it difficult to elucidate the mechanisms underlying acute and even more persistent PTH (PPTH). Furthermore, psychiatric comorbidities such as post-traumatic stress disorder (PTSD), previous history of migraine, and legal issues often reported by PPTH patients have complicated the understanding of this condition, hence treatment approaches for PTH remain problematic. Recent findings from structural and functional neuroimaging studies have attempted to describe the brain architecture of PPTH, suggesting the involvement of different networks compared to migraine. It also seems that calcitonin gene-related peptide (CGRP) levels are not particularly raised in PPTH, although CGRP monoclonal antibodies have obtained positive initial open-label evidence of efficacy in PPTH, and more trials assessing the efficacy of this class of treatments are underway. The broad overlap between PTH, migraine, and PTSD suggests that research in this field should start with a re-appraisal of the diagnostic criteria, followed by methodologically sound epidemiological and clinical studies. Preclinical research should strive to create more reliable PTH models to support human neuroimaging, neurochemical, and neurogenetic studies, aiming to underpin new pathophysiological hypotheses that may expand treatment targets and improve the management of PTH patients.

American Academy of Clinical Neuropsychology (AACN) 2021 consensus statement on validity assessment: Update of the 2009 AACN consensus conference statement on neuropsychological assessment of effort, response bias, and malingering

Objective: Citation and download data pertaining to the 2009 AACN consensus statement on validity assessment indicated that the topic maintained high interest in subsequent years, during which key terminology evolved and relevant empirical research proliferated. With a general goal of providing current guidance to the clinical neuropsychology community regarding this important topic, the specific update goals were to: identify current key definitions of terms relevant to validity assessment; learn what experts believe should be reaffirmed from the original consensus paper, as well as new consensus points; and incorporate the latest recommendations regarding the use of validity testing, as well as current application of the term 'malingering.' Methods: In the spring of 2019, four of the original 2009 work group chairs and additional experts for each work group were impaneled. A total of 20 individuals shared ideas and writing drafts until reaching consensus on January 21, 2021. Results: Consensus was reached regarding affirmation of prior salient points that continue to garner clinical and scientific support, as well as creation of new points. The resulting consensus statement addresses definitions and differential diagnosis, performance and symptom validity assessment, and research design and statistical issues. Conclusions/Importance: In order to provide bases for diagnoses and interpretations, the current consensus is that all clinical and forensic evaluations must proactively address the degree to which results of neuropsychological and psychological testing are valid. There is a strong and continually-growing evidence-based literature on which practitioners can confidently base their judgments regarding the selection and interpretation of validity measures.

Is the Rivermead Post-Concussion Symptoms Questionnaire a Reliable and Valid Measure to Assess Long-Term Symptoms in Traumatic Brain Injury and Orthopedic Injury Patients? A Novel Investigation Using Rasch Analysis

Persistent post-concussion syndrome (PCS) symptoms are known to last years after traumatic brain injury (TBI), and similar symptoms are increasingly being documented among those who have not experienced a TBI. There remains however, a dearth of empirical evidence on the structural composition of symptoms beyond the post-acute symptom phase after TBI, and little is known about the potential use of PCS symptom scales to measure PCS-like symptoms in non-TBI individuals. Our objective was therefore to examine the psychometric performance and dimensionality of the Rivermead Post-Concussion Symptoms Questionnaire (RPQ) as a measure of long-term PCS symptoms among a TBI and non-TBI sample. A case-control sample of 223 patients with injury, consisting of age- and sex-matched TBI participants (n = 109) and orthopedic participants (n = 114) were recruited from a regional trauma registry in New Zealand (NZ), and assessed at mean 2.5 years post-injury. Results from the Rasch analysis showed that the RPQ achieved fit to the Rasch model, demonstrating very good reliability (Person Separation Index [PSI] = 0.87), thereby indicating that the measure can be used reliably for individual and group assessment of symptoms among both TBI and orthopedic patients. In this study we demonstrated evidence of a unidimensional construct of PCS symptoms in both groups, which helps alleviate previous uncertainty about factor structure, and permits the calculation of a total RPQ score. Conversion of ordinal to interval total scores presented within are recommended for clinicians and researchers, to improve instrument precision, and to facilitate the interpretation of change scores and use of parametric methods in data analysis.

Network Analysis and Precision Rehabilitation for the Post-concussion Syndrome

Some people experience persistent symptoms following a mild traumatic brain injury (MTBI), and the etiology of those symptoms has been debated for generations. Post-concussion-like symptoms are caused by many factors both before and after MTBI, and this non-specificity is the bedrock of the conundrum regarding the existence of the post-concussion syndrome. A latent model or common cause theory for the syndrome is inconsistent with the prevailing biopsychosocial conceptualization. It is the thesis of this paper that adopting a network perspective for persistent symptoms following MTBI, including the post-concussion syndrome, could lead to new insights and targeted treatment and rehabilitation strategies. The network perspective posits that symptoms co-occur because they are strongly inter-related, activating, amplifying, and mutually reinforcing, not because they arise from a common latent disease entity. This approach requires a conceptual shift away from thinking that symptoms reflect an underlying disease or disorder toward viewing inter-related symptoms as constituting the syndrome or disorder. The symptoms do not arise from an underlying syndrome—the symptoms are the syndrome. A network analysis approach allows us to embrace heterogeneity and comorbidity, and it might lead to the identification of new approaches to sequenced care. The promise of precision rehabilitation requires us to better understand the interconnections among symptoms and problems so that we can produce more individualized and effective treatment and rehabilitation.

Postconcussion symptom reporting is not associated with diffusion tensor imaging findings in the subacute to chronic phase of recovery in military service members following mild traumatic brain injury

INTRODUCTION

The purpose of this study was to examine the relation between white matter integrity of the brain and postconcussion symptom reporting following mild traumatic brain injury (MTBI).

METHOD

Participants were 109 U.S. military service members (91.7% male) who had sustained a MTBI (n = 88) or orthopedic injury without TBI (trauma controls, TC, n = 21), enrolled from the Walter Reed National Military Medical Center, Bethesda, Maryland. Participants completed a battery of neurobehavioral symptom measures and underwent diffusion tensor imaging (DTI; General Electric 3T) of the whole brain, on average 44.9 months post injury (SD = 42.3). Measures of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were generated for 18 regions of interest (ROIs). Participants in the MTBI group were divided into two subgroups based on International Classification of Diseases-10th Revision (ICD-10) Category C criteria for postconcussion syndrome (PCS): PCS-present (n = 41) and PCS-absent (n = 47).

RESULTS

The PCS-present group had significantly worse scores on all 13 neurobehavioral measures than the PCS-absent group (p < .001, d = 0.87-2.50) and TC group (p < .003, d = 0.84-2.06). For all ROIs, there were no significant main effects across the three groups for FA, MD, AD, and RD (all ps >.03). Pairwise comparisons revealed no significant differences for all ROIs when using FA and RD, and only two significant pairwise differences were found between PCS-present and PCS-absent groups when using MD and AD [i.e., anterior thalamic radiation and cingulate gyrus (supracallosal) bundle].

CONCLUSIONS

Consistent with past research, but not all studies, postconcussion symptom reporting was not associated with white matter integrity in the subacute to chronic phase of recovery following MTBI.

Concussion and the autonomic nervous system: An introduction to the field and the results of a systematic review

BACKGROUND

Recent evidence suggests that autonomic nervous dysfunction may be one of many potential factors contributing to persisting post-concussion symptoms.

OBJECTIVE

This is the first systematic review to explore the impact of concussion on multiple aspects of autonomic nervous system functioning.

METHODS

The methods employed are in compliance with the American Academy of Neurology (AAN) and PRISMA standards. Embase, MEDLINE, PsychINFO, and Science Citation Index literature searches were performed using relevant indexing terms for articles published prior to the end of December 2016. Data extraction was performed by two independent groups, including study quality indicators to determine potential risk for bias according to the 4-tiered classification scheme of the AAN.

RESULTS

Thirty-six articles qualified for inclusion in the analysis. Only three studies (one Class II and two Class IV) did not identify anomalies in measures of ANS functioning in concussed populations.

CONCLUSIONS

The evidence supports the conclusion that it is likely that concussion causes autonomic nervous system anomalies. An awareness of this relationship increases our understanding of the physical impact of concussion, partially explains the overlap of concussion symptoms with other medical conditions, presents opportunities for further research, and has the potential to powerfully inform treatment decisions.

Concussion

Concussion has been recognized as a clinical entity for more than 1000 years. Throughout the 20th century it was studied extensively in boxers, but it did not pique the interest of the general population because it is the accepted goal of the boxer to inflict such an injury on their opponent. In 2002, however, the possibility that repetitive concussions could result in chronic brain damage and a progressive neurologic disorder was raised by a postmortem evaluation of a retired player in the most popular sports institution in the United States, the National Football League. Since that time concussion has been a frequent topic of conversation in homes, schools, and on television and has become a major focus of sports programs in communities and schools at all levels. Now all 50 states, the District of Columbia, and the National Collegiate Athletic Association have enacted laws and rules to protect the athlete.

Associations Between Traumatic Brain Injury History and Future Headache Severity in Veterans: A Longitudinal Study

OBJECTIVE

To determine whether traumatic brain injury (TBI) history is associated with worse headache severity outcomes.

DESIGN

Prospective cohort study.

SETTING

Department of Veterans Affairs (VA) outpatient clinics.

PARTICIPANTS

Veterans (N=2566) who completed a mail follow-up survey an average of 3 years after a comprehensive TBI evaluation (CTBIE).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The presence or absence of TBI, and TBI severity were evaluated by a trained clinician and classified according to VA/Department of Defense clinical practice guidelines. Headache severity was evaluated at both the baseline CTBIE assessment and 3-year follow-up using a 5-level headache score ranging from 0 ("none") to 4 ("very severe") based on headache-associated activity interference in the past 30 days. We examined associations of mild and moderate/severe TBI history, as compared to no TBI history, with headache severity in cross-sectional and longitudinal analyses, with and without adjustment for potential confounders.

RESULTS

Mean headache severity scores were 2.4 at baseline and 2.3 at 3-year follow-up. Mild TBI was associated with greater headache severity in multivariate-adjusted cross-sectional analyses (β [SE]=.61 [.07], P<.001), as compared with no TBI, but not in longitudinal analyses (β [SE]=.09 [.07], P=.20). Moderate/severe TBI was significantly associated with greater headache severity in both cross-sectional (β [SE]=.66 [.09], P<.001) and longitudinal analyses (β [SE]=.18 [.09], P=.04).

CONCLUSIONS

Headache outcomes are poor in veterans who receive VA TBI evaluations, irrespective of past TBI exposure, but significantly worse in those with a history of moderate/severe TBI. No association was found between mild TBI and future headache severity in veterans. Veterans with headache presenting for TBI evaluations, and particularly those with moderate/severe TBI, may benefit from further evaluation and treatment of headache.

Postconcussion symptoms reported by Operation Enduring Freedom/Operation Iraqi Freedom veterans with and without blast exposure, mild traumatic brain injury, and posttraumatic stress disorder

OBJECTIVE

This study examined symptom reporting related to the 10th Edition of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) criteria for postconcussional syndrome (PCS) in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF) Veterans. Our aims were to: (a) examine relationships among PCS symptoms by identifying potential subscales of the British Columbia Postconcussion Symptom Inventory (BC-PSI); and (b) examine group differences in BC-PSI items and subscales in Veterans with and without blast exposure, mild traumatic brain injury (mTBI), and posttraumatic stress disorder (PTSD).

METHOD

Our sample included Veterans with blast-related mTBI history (n = 47), with blast exposure but no mTBI history (n = 20), and without blast exposure (n = 23). Overall, 37 Veterans had PTSD, and 53 did not. We conducted an exploratory factor analysis (EFA) of the BC-PSI followed by multivariate analysis of variance to examine differences in BC-PSI subscale scores by blast exposure, mTBI history, and PTSD.

RESULTS

BC-PSI factors were interpreted as cognitive, vestibular, affective, anger, and somatic. Items and factor scores were highest for Veterans with blast exposure plus mTBI, and lowest for controls. Vestibular, affective, and somatic factors were significantly higher for Veterans with blast exposure plus mTBI than for controls, but not significantly different for those with blast exposure but no mTBI. These results remained significant when PTSD symptom severity was included as a covariate. Cognitive, anger, and somatic subscales were significantly higher for Veterans with PTSD, though there was no interaction effect of PTSD and mTBI or blast history.

CONCLUSIONS

EFA-derived subscales of the BC-PSI differentiated Veterans based on blast exposure, mTBI history, and PTSD.

Female Service Members and Symptom Reporting after Combat and Non-Combat-Related Mild Traumatic Brain Injury

Females are often excluded from military-related mild traumatic brain injury (mTBI) research because of its relatively low prevalence in this population. The purpose of this study was to focus on outcome from mTBI in female service members, compared with males. Participants were 172 United States military service members selected from a larger sample that had sustained an mTBI, and were evaluated within 24 months of injury (Age: mean = 28.9, SD = 8.1) at one of six military medical centers. Eighty-six women were matched to 86 men on nine key variables: TBI severity, mechanism of injury, bodily injury severity, days post-injury, age, number of deployments, theater where wounded, branch of service, and rank. Participants completed the Neurobehavioral Symptom Inventory (NSI) and the Posttraumatic Stress Disorder Checklist (PCL-C). There were no meaningful gender differences across all demographic and injury-related variables (p > 0.05). There were significant group differences and medium effect sizes for the NSI total score and all four NSI cluster scores. Symptoms most affected related to nausea, sensitivity to light, change in taste/smell, change in appetite, fatigue, and poor sleep. There were significant group differences and small-medium effect sizes for the PCL-C total score and two of the three PCL-C cluster scores. Symptoms most affected related to poor concentration, trouble remembering a stressful event, and disturbing memories/thoughts/images. Females consistently experienced more symptoms than males. As females become more active in combat-related deployments, it is critical that future studies place more emphasis on this important military population.

Postconcussion syndrome: a review

Postconcussion syndrome is as yet a poorly understood and controversial disorder. This article reviews a range of research considering the causes, symptoms, and possible interventions for postconcussion syndrome.

Mild traumatic brain injury

Mild traumatic brain injury (TBI) is common but accurate diagnosis and defining criteria for mild TBI and its clinical consequences have been problematic. Mild TBI causes transient neurophysiologic brain dysfunction, sometimes with structural axonal and neuronal damage. Biomarkers, such as newer imaging technologies and protein markers, are promising indicators of brain injury but are not ready for clinical use. Diagnosis relies on clinical criteria regarding depth and duration of impaired consciousness and amnesia. These criteria are particularly difficult to confirm at the least severe end of the mild TBI continuum, especially when relying on subjective, retrospective accounts. The postconcussive syndrome is a controversial concept because of varying criteria, inconsistent symptom clusters and the evidence that similar symptom profiles occur with other disorders, and even in a proportion of healthy individuals. The clinical consequences of mild TBI can be conceptualized as two multidimensional disorders: (1) a constellation of acute symptoms that might be termed early phase post-traumatic disorder (e.g., headache, dizziness, imbalance, fatigue, sleep disruption, impaired cognition), that typically resolve in days to weeks and are largely related to brain trauma and concomitant injuries; (2) a later set of symptoms, a late phase post-traumatic disorder, evolving out of the early phase in a minority of patients, with a more prolonged (months to years), sometimes worsening set of somatic, emotional, and cognitive symptoms. The later phase disorder is highly influenced by a variety of psychosocial factors and has little specificity for brain injury, although a history of multiple concussions seems to increase the risk of more severe and longer duration symptoms. Effective early phase management may prevent or limit the later phase disorder and should include education about symptoms and expectations for recovery, as well as recommendations for activity modifications. Later phase treatment should be informed by thoughtful differential diagnosis and the multiplicity of premorbid and comorbid conditions that may influence symptoms. Treatment should incorporate a hierarchical, sequential approach to symptom management, prioritizing problems with significant functional impact and effective, available interventions (e.g., headache, depression, anxiety, insomnia, vertigo).

Premorbid predictors of postconcussion symptoms in collegiate athletes

INTRODUCTION

In recent years, the sports community has been faced with the challenge of determining when it is safe to return concussed athletes to play. Given that return-to-play decisions are partially dependent upon athletes' endorsement of symptoms, better understanding what factors contribute to the presence of symptoms following concussion is crucial. The purpose of the present study was to better characterize the symptoms that athletes endorse at baseline and to determine what impact various premorbid (or preinjury) characteristics have on the presence and severity of postconcussion symptoms in the acute injury period following concussion.

METHOD

Two groups of participants with similar ages and levels of education were examined: athletes at baseline (N = 702) and postconcussion (N = 55). Athletes were administered a comprehensive battery of neuropsychological tests, consisting of neurocognitive and neurobehavioral measures, at both time periods. The main outcome measure was the Post-Concussion Symptoms Scale (PCSS). A factor analysis was conducted on the participants' baseline PCSS data to determine the factor structure of the PCSS, and separate logistic regression analyses were conducted that examined the baseline PCSS symptom clusters (derived from the factor analysis), demographic variables, and baseline neurocognitive variables as predictors of dichotomized postconcussion PCSS total scores (i.e., low versus high symptom reporting following concussion).

RESULTS

Four distinct clusters emerged from the factor analysis measuring cognitive, physical, affective, and sleep symptoms. Logistic regression results indicated that the physical and affective symptom clusters at baseline reliably predicted athletes' postconcussion symptom group, as did sex and the neurocognitive composite score.

CONCLUSIONS

These findings show that certain baseline characteristics of athletes confer risk for greater symptomatology postconcussion. Knowledge of these risk factors can assist the management and treatment of sports-related concussion.

Diffusion tensor imaging findings and postconcussion symptom reporting six weeks following mild traumatic brain injury

The purpose of this study is to examine the relation between the microstructural architecture of white matter, as measured by diffusion tensor imaging (DTI), and postconcussion symptom reporting 6-8 weeks following mild traumatic brain injury (MTBI). Participants were 108 patients prospectively recruited from a Level 1 Trauma Center (Vancouver, BC, Canada) following an orthopedic injury [i.e., 36 trauma controls (TCs)] or MTBI (n = 72). DTI of the whole brain was undertaken using a Phillips 3T scanner at 6-8 weeks postinjury. Participants also completed a 5 h neurocognitive test battery and a brief battery of self-report measures (e.g., depression, anxiety, and postconcussion symptoms). The MTBI sample was divided into two groups based on ICD-10 criteria for postconcussional syndrome (PCS): first, PCS-present (n = 20) and second, PCS-absent (n = 52). There were no significant differences across the three groups (i.e., TC, PCS-present, and PCS-absent) for any of the neurocognitive measures (p = .138-.810). For the self-report measures, the PCS-present group reported significantly more anxiety and depression symptoms compared with the PCS-absent and TC groups (p < .001, d = 1.63-1.89, very large effect sizes). For the DTI measures, there were no significant differences in fractional anisotropy, axial diffusivity, radial diffusivity, or mean diffusivity when comparing the PCS-present and PCS-absent groups. However, there were significant differences (p < .05) in MD and RD when comparing the PCS-present and TC groups. There were significant differences in white matter between TC subjects and the PCS-present MTBI group, but not the PCS-absent MTBI group. Within the MTBI group, white-matter changes were not a significant predictor of ICD-10 PCS.

Sustained outcomes following mild traumatic brain injury: results of a five-emergency department longitudinal study

OBJECTIVE

To report on the occurrence of sustained outcomes including post-concussion symptoms, health services used and indicators of social disruption following a mild traumatic brain injury (MTBI).

RESEARCH DESIGN

A dual cohort comparing MTBI Emergency Department (ED) patients and a comparison group of non-head injured ED patients.

METHODS AND PROCEDURES

The outcomes measures employed were the Rivermead Post-Concussion Symptoms Questionnaire (RPQ) and indicators of health services used and social disruption all recorded at the ED and at 3 and 6 months post-ED discharge. 'Sustained' meant a positive response to these measures at 3 and 6 months.

MAIN OUTCOMES AND RESULTS

Reasonable follow-up success was achieved at 3 and 6 months and the cohorts were alike on all demographic descriptors. RPQ average score and symptom occurrence were far more frequent among MTBI patients than for the comparison cohort from 3 to 6 months. The use of health services and indicators of social disruption were also more frequent among MTBI post-discharge patients.

CONCLUSIONS

These findings argue that some with an MTBI suffer real complaints and they are sustained from 3 to at least 6 months. More effort should be given toward specificity of these symptoms from those reported by members of the comparison group.

Neurogenic and psychogenic acute postconcussion symptoms can be identified after mild traumatic brain injury

OBJECTIVES

As provenance of postconcussion symptoms after mild traumatic brain injury (mTBI) is controversial, with similar rates found in other populations, we aimed to identify postconcussion symptoms specific to mTBI compared with controls. We also compared differences between complicated and uncomplicated mTBIs.

SETTING

Hospital emergency department.

PARTICIPANTS

Adult individuals (34 individuals with complicated mTBI, 76 individuals with uncomplicated mTBI, and 47 orthopedic controls) who sought care in the emergency department and were consecutively recruited by post at 2 weeks postinjury.

MAIN MEASURES

Rivermead Postconcussion Symptom Questionnaire. Preinjury factors were used as covariates.

RESULTS

Compared with orthopedic controls, complicated mTBI group reported greater severity of headaches, dizziness, and nausea, as well as concentration difficulties, suggesting that these are neurogenic. Severity of other symptoms measured on the Rivermead Postconcussion Symptom Questionnaire was not significantly different between these groups, suggesting that these are psychogenic. Differences were evident between the 2 mTBI samples on the items of dizziness, nausea, fatigue, sleep disturbance, and concentration difficulties.

CONCLUSIONS

Neurogenic and psychogenic postconcussion symptoms were identified at the acute-phase postinjury. Findings suggest that treating persons with mTBI as a homogenous sample is not prudent. This should inform prognostic models and follow-up support offered after leaving the emergency department.

Factors influencing postconcussion and posttraumatic stress symptom reporting following military-related concurrent polytrauma and traumatic brain injury

The purpose of this study was to identify factors that are predictive of, or associated with, high endorsement of postconcussion and posttraumatic stress symptoms following military-related traumatic brain injury (TBI). Participants were 1,600 U.S. service members (age: M = 27.1, SD = 7.1; 95.4% male) who had sustained a mild-to-moderate TBI and who had been evaluated by the Defense and Veterans Brain Injury Center at one of six military medical centers. Twenty-two factors were examined that included demographic, injury circumstances/severity, treatment/evaluation, and psychological/physical variables. Four factors were statistically and meaningfully associated with clinically elevated postconcussion symptoms: (i) low bodily injury severity, (ii) posttraumatic stress, (iii) depression, and (iv) military operation where wounded (p < .001, 43.2% variance). The combination of depression and posttraumatic stress symptoms accounted for the vast majority of unique variance (41.5%) and were strongly associated with, and predictive of, clinically elevated postconcussion symptoms [range: odds ratios (OR) = 4.24-7.75; relative risk (RR) = 2.28-2.51]. Five factors were statistically and meaningfully associated with clinically elevated posttraumatic stress symptoms: (i) low bodily injury severity, (ii) depression, (iii) a longer time from injury to evaluation, (iv) military operation where wounded, and (v) current auditory deficits (p < .001; 65.6% variance accounted for). Depression alone accounted for the vast majority of unique variance (60.0%) and was strongly associated with, and predictive of, clinically elevated posttraumatic stress symptoms (OR = 38.78; RR = 4.63). There was a very clear, strong, and clinically meaningful association between depression, posttraumatic stress, and postconcussion symptoms in this sample. Brain injury severity, however, was not associated with symptom reporting following TBI.

Health service and medication use among veterans with persistent postconcussive symptoms

Persistent postconcussive symptoms (PPCS) are noted when a series of cognitive, emotional, and somatosensory complaints persist for months after a concussion. Clinical management of PPCS can be challenging in the veteran population because of the nonspecific nature of symptoms and co-occurrence with affective disturbances such as posttraumatic stress disorder (PTSD) and chronic pain. In this study, we compared health service and medication use patterns in a sample of 421 veterans with PPCS with an age-matched cohort of case controls. The results suggest that the veterans with PPCS showed high rates of medical and mental health service utilization during a mean treatment period of 2 years. Although chronic pain commonly co-occurs with PPCS in veterans, service use and medication prescribing trends seem to have been influenced more by the presence of PTSD than chronic pain. Our findings reinforce the overlap among PPCS, PTSD, and chronic pain and demonstrate the complexity inherent in treating these conditions in veterans.

Posttraumatic headaches in civilians, soldiers, and athletes

Posttraumatic headaches are one of the most common and controversial secondary headache types. After mild head injury, more than 50% of people develop a postconcussion syndrome which has been controversial for more than 150 years. Headache is estimated as present in 30% to 90% of patients after mild head injury. Most headaches are of the tension type, although migraines can increase in frequency or occur acutely or chronically de novo. A review is provided of headaches in civilians, soldiers after blast trauma, athletes, and post-craniotomy including pathogenesis. The treatments are the same as for the primary phenotypes.

Managing behavioral health needs of veterans with traumatic brain injury (TBI) in primary care

Traumatic brain injury (TBI) is a frequent occurrence in the United States, and has been given particular attention in the veteran population. Recent accounts have estimated TBI incidence rates as high as 20 % among US veterans who served in Afghanistan or Iraq, and many of these veterans experience a host of co-morbid concerns, including psychiatric complaints (such as depression and post-traumatic stress disorder), sleep disturbance, and substance abuse which may warrant referral to behavioral health specialists working in primary care settings. This paper reviews many common behavioral health concerns co-morbid with TBI, and suggests areas in which behavioral health specialists may assess, intervene, and help to facilitate holistic patient care beyond the acute phase of injury. The primary focus is on sequelae common to mild and moderate TBI which may more readily present in primary care clinics.

Diffusion tensor imaging findings are not strongly associated with postconcussional disorder 2 months following mild traumatic brain injury

OBJECTIVE

To examine the relation between diffusion tensor imaging (DTI) of the corpus callosum and postconcussion symptom reporting following mild traumatic brain injury (MTBI).

PARTICIPANTS

Sixty patients with MTBI and 34 patients with orthopedic/soft-tissue injuries (Trauma Controls) prospectively enrolled from consecutive admissions to a level 1 trauma center.

PROCEDURE

Diffusion tensor imaging of the corpus callosum was undertaken using a Phillips 3T scanner at 6 to 8 weeks postinjury. Participants also completed a postconcussion symptom checklist. The MTBI group was divided into 2 subgroups based on the International Classification of Diseases, Tenth Revision symptom criteria for postconcussion disorder (PCD): PCD Present (n = 21), PCD Absent (n = 39).

MAIN OUTCOME MEASURES

Measures of fractional anisotropy and mean diffusivity for the genu, body, and splenium of the corpus callosum. Participants also completed the British Columbia Post-Concussion Symptom Inventory.

RESULTS

The MTBI group reported more postconcussion symptoms than the trauma controls. There were no significant differences between MTBI and trauma control groups on all DTI measures. In the MTBI sample, there were no significant differences on all DTI measures between those who did and did not meet the International Classification of Diseases, Tenth Revision research criteria for postconcussion disorder.

CONCLUSIONS

These data do not support an association between white matter integrity in the corpus callosum and self-reported postconcussion syndrome 6 to 8 weeks post-MTBI.

Mild traumatic brain injury (concussion), posttraumatic stress disorder, and depression in U.S. soldiers involved in combat deployments: association with postdeployment symptoms

OBJECTIVES

Several studies have examined the relationship between concussion/mild traumatic brain injury (mTBI), posttraumatic stress disorder (PTSD), depression, and postdeployment symptoms. These studies indicate that the multiple factors involved in postdeployment symptoms are not accounted for in the screening processes of the Department of Defense/Veteran's Affairs months after concussion injuries. This study examined the associations of single and multiple deployment-related mTBIs on postdeployment health.

METHODS

A total of 1502 U.S. Army soldiers were administered anonymous surveys 4 to 6 months after returning from deployment to Iraq or Afghanistan assessing history of deployment-related concussions, current PTSD, depression, and presence of postdeployment physical and neurocognitive symptoms.

RESULTS

Of these soldiers, 17% reported an mTBI during their previous deployment. Of these, 59% reported having more than one. After adjustment for PTSD, depression, and other factors, loss of consciousness was significantly associated with three postconcussive symptoms, including headaches (odds ratio [OR] = 1.5, 95% confidence interval [CI] = 1.1-2.3). However, these symptoms were more strongly associated with PTSD and depression than with a history of mTBI. Multiple mTBIs with loss of consciousness increased the risk of headache (OR = 4.0, 95% CI = 2.4-6.8) compared with a single occurrence, although depression (OR = 4.2, 95% CI = 2.6-6.8) remained as strong a predictor.

CONCLUSIONS

These data indicate that current screening tools for mTBI being used by the Department of Defense/Veteran's Affairs do not optimally distinguish persistent postdeployment symptoms attributed to mTBI from other causes such as PTSD and depression. Accumulating evidence strongly supports the need for multidisciplinary collaborative care models of treatment in primary care to collectively address the full spectrum of postwar physical and neurocognitive health concerns.

Characteristics of acute posttraumatic headache following mild head injury

BACKGROUND

To examine the prevalence and characteristics of acute posttraumatic headache (APTH) attributed to mild head injury within a prospective, observational study design.

METHODS

We recruited 100 patients with acute mild head injury as defined in the International Classification of Headache Disorders, 2nd Edition (ICHD-2) presenting to the department of trauma surgery at the Medical University of Vienna. Patients underwent a detailed telephone interview between days 7 and 10 and between days 90 and 100 after the injury.

RESULTS

The prevalence of APTH was 66%. APTH had occurred within 24 hours after the trauma in 78% and lasted for a median of 3.0 days. Headache was unilateral in 45%. Aggravation by physical activity, nausea and photo-/phonophobia was present in 49%, 42% and 55%, respectively. The prevalence of APTH was related to conditions of chronic pain (excluding headache), pre-existing episodic headache, number of posttraumatic symptoms, anxiety and depression. At follow-up at 90-100 days, posttraumatic headache had abated in all patients.

CONCLUSIONS

APTH attributed to mild head injury is a common but self-limiting condition frequently showing migrainous features. Participants with chronic pain other than headache, pre-existing headache and affective disorders are at higher risk of developing APTH. None of the patients developed chronic posttraumatic headache.

Clinical electrophysiologic assessments and mild traumatic brain injury: state-of-the-science and implications for clinical practice

Conventional and quantitative electroencephalography (EEG and qEEG, respectively) may enhance clinical diagnosis and treatment planning provided to persons with mild traumatic brain injury (mTBI) and postconcussive symptoms. Effective and appropriate use of EEG and qEEG in this context requires expert-level knowledge of these technologies, mTBI, and the differential diagnosis for postconcussive symptoms. A practical and brief review from the perspective of a clinician-scientist engaged principally in the care and study of persons with mTBI therefore may be of use and value to other clinicians and scientists interested in these matters. Toward that end, this article offers an overview of the current applications of conventional EEG and qEEG to the study and clinical evaluation of persons with mTBI. The clinical case definition of TBI, the differential diagnosis of post-injury neuropsychiatric disturbances, and the typical course of recovery following mTBI are reviewed. With this background and context, the strengths and limitations of the literature describing EEG and qEEG studies in this population are considered. The implications of this review on the applications of these electrophysiologic assessments to the clinical evaluation of persons with mTBI and postconcussive symptoms are then considered. Finally, suggestions are offered regarding the design of future studies using these technologies in this population. Although this review may be of interest and value to professionals engaged in clinical or research electrophysiology in their daily work, it is intended to serve more immediately the needs of clinicians less familiar with these types of clinical electrophysiologic assessments.