Sleep Disorders Associated With Mild Traumatic Brain Injury Using Sport Concussion Assessment Tool 3

The Association Among Clinical Profiles, Modifiers, and Prolonged Recovery in Adolescents With Sport-Related Concussion

OBJECTIVE

The purposes were to (1) describe the prevalence of clinical profiles and modifiers, (2) examine the association between clinical profiles and prolonged recovery, and (3) examine the interaction between clinical profiles and modifiers and prolonged recovery in adolescents with sport-related concussion (SRC).

DESIGN

Retrospective, cross-sectional.

SETTING

Interdisciplinary specialty sports concussion clinic.

PATIENTS

Patients (n = 299) aged 12 to 19 years who were diagnosed with SRC within 30 days of injury.

INDEPENDENT VARIABLES

Clinical profiles and modifiers were decided by the clinical judgment of the clinical neuropsychologist and sports medicine physician, using data from the Clinical Profile Screen and information gathered from the clinical interview, neurocognitive, and vestibular and ocular motor testing.

MAIN OUTCOME MEASURES

Prolonged recovery was defined as ≥28 days from the date of injury to the date of clearance.

RESULTS

The most common clinical profiles were migraine (34.8%) and cognitive-fatigue (23.4%). There were no significant relationships between clinical profiles and prolonged recovery (Wald = 5.89, df = 4, P = 0.21). The presence of a modifier did not significantly affect the relationship between clinical profiles and prolonged recovery ( = 6.5, df = 5, P = 0.26). The presence of any modifier yielded a 10-day increase in median recovery time within the cognitive/fatigue clinical profile (Wilcoxon rank-sum = 268.5, P = 0.01).

CONCLUSIONS

Although patients with a clinical profile and modifier may not experience prolonged recovery, they may experience longer recovery time than patients with a clinical profile and no modifier.

Sleep/Wake Disorders After Sports Concussion: Risks, Revelations, and Interventions

SUMMARY

Sleep-wake disturbances (SWDs) are among the most prevalent, persistent, and often disregarded sequelae of traumatic brain injury. Identification and treatment of SWDs in patients with traumatic brain injury is important and can complement other efforts to promote maximum functional recovery. SWDs can accentuate other consequences of traumatic brain injury, negatively affect mood, exacerbate pain, heighten irritability, and diminish cognitive abilities and the potential for recovery. The risk for sports injuries increases when athletes are sleep deprived. Sleep deprivation increases risk-taking behaviors, predisposing to injuries. SWDs are an independent risk factor for prolonged recovery after sports-related concussion. SWDs following sports-related concussion have been shown to impede recovery, rehabilitation, and return to preinjury activities.

Home-Based Measurements of Nocturnal Cardiac Parasympathetic Activity in Athletes during Return to Sport after Sport-Related Concussion

Sport-related concussions (SRC) are characterized by impaired autonomic control. Heart rate variability (HRV) offers easily obtainable diagnostic approaches to SRC-associated dysautonomia, but studies investigating HRV during sleep, a crucial time for post-traumatic cerebral regeneration, are relatively sparse. The aim of this study was to assess nocturnal HRV in athletes during their return to sports (RTS) after SRC in their home environment using wireless wrist sensors (E4, Empatica, Milan, Italy) and to explore possible relations with clinical concussion-associated sleep symptoms. Eighteen SRC athletes wore a wrist sensor obtaining photoplethysmographic data at night during RTS as well as one night after full clinical recovery post RTS (>3 weeks). Nocturnal heart rate and parasympathetic activity of HRV (RMSSD) were calculated and compared using the Mann-Whitney U Test to values of eighteen; matched by sex, age, sport, and expertise, control athletes underwent the identical protocol. During RTS, nocturnal RMSSD of SRC athletes (Mdn = 77.74 ms) showed a trend compared to controls (Mdn = 95.68 ms, p = 0.021, r = -0.382, p adjusted using false discovery rate = 0.126) and positively correlated to "drowsiness" (r = 0.523, p = 0.023, p adjusted = 0.046). Post RTS, no differences in RMSSD between groups were detected. The presented findings in nocturnal cardiac parasympathetic activity during nights of RTS in SRC athletes might be a result of concussion, although its relation to recovery still needs to be elucidated. Utilization of wireless sensors and wearable technologies in home-based settings offer a possibility to obtain helpful objective data in the management of SRC.

Functional Outcomes, Injury Variables, and Athlete Characteristics Associated with Post-Concussion Sleep Disturbance

OBJECTIVE

To examine the relationship between sleep disturbance and functional outcomes following a concussion. Also, to explore athlete and injury-related variables that may be related to risk factors for poor sleep following concussion.

METHOD

124 collegiate athletes completed a neuropsychological evaluation within 14 days of sustaining a sport-related concussion (SRC). Athletes were categorized as sleep disturbed (n = 52) or not sleep disturbed (n = 72). Outcome variables included symptom reports, cognitive performance (mean performance and variability), and mood (depression). Injury characteristics and athlete characteristics explored were loss of consciousness (LOC) associated with the injury, whether the athlete was immediately removed from play, and history of prior concussions.

RESULTS

Sleep disturbed athletes reported more symptoms, F(4, 119) = 7.82, p < 0.001, ƞ2 = 0.21, were more likely to be symptomatic at the time of testing, χ2(1, N = 124) = 19.79, p < 0.001, φ = 0.40, and were marginally more likely to experience clinically significant depression, χ2(1, N = 120) = 3.03, p = 0.08, φ = 0.16, than not sleep disturbed athletes. There were no cognitive differences between the groups, p > 0.05. A greater proportion of sleep disturbed athletes experienced LOC (30%) compared to not sleep disturbed athletes (13%), χ2(1, N = 118) = 4.99, p = 0.03, φ = -0.21.

CONCLUSION

Sleep disturbances following SRC are associated with a broad range of self-reported symptoms. LOC may be associated with an increased risk of developing sleep disturbances; alternatively, sleep disturbances may increase the risk of LOC following concussion.

Sleep Disorders in Traumatic Brain Injury

SUMMARY

Sleep disorders are common after traumatic brain injury (TBI). This study will review the spectrum and proposed mechanisms of TBI-associated sleep disorders and discuss the clinical approach to diagnosis and management of them. Disordered and fragmented sleep with insomnia and daytime sleepiness is very common after TBI. Sleep disruption contributes to morbidity and neurocognitive and neurobehavioral deficits and prolongs the recovery phase after injury. Early recognition and correction of these problems may limit the secondary effects of TBI and improve patient outcomes. Evaluating sleep disorders in TBI should be an important component of TBI assessment and management. Finally, newer research techniques for early diagnosis, prognosis, and improved outcomes after TBI will also be addressed.

Characterizing Sleep and Wakefulness in the Acute Phase of Concussion in the General Population: A Naturalistic Cohort from the Toronto Concussion Study

Growing literature links concussion to changes in sleep and wakefulness in humans and in rodent models. Sleep has been linked with synaptic reorganization under other conditions; however, the characterization and role of sleep after acute concussion remains poorly understood. While much research has focused on insomnia among patients with chronic or persistent concussion symptoms, there is limited understanding of sleep and acute concussion, its potential role in recovery, and associated risk factors for the development of chronic sleep disturbance. Studies to date are limited by small sample sizes of primarily athlete or military populations. Additional studies among the general population are critical to inform best practice guidelines. We examined the sleep and daytime wakefulness of 472 adults from a naturalistic general population cohort (mean age, 33.3 years, females = 60.8%) within seven days of diagnosed concussion, using a validated, condition-specific measure, the Sleep and Concussion Questionnaire. Participants identified immediate changes in sleep characterized by hypersomnia and difficulty maintaining daytime wakefulness; 35% considered these changes as moderate to severe and 79% required monitoring or follow-up. Females experienced significantly greater severity of changes in sleep compared with males. Positive correlations between severity of sleep and pain and headache were identified. Differences by sex are an important consideration for early intervention and long-term monitoring. Because sleep was compromised by pain, pain management is also an integral part of early intervention. Our findings suggest that assessment of sleep beginning in the acute stage is a critical component of concussion management in the general population.

Influence of Sleep Dysfunction on Concussion Assessment Outcomes Among Adolescent Athletes After Concussion and Healthy Controls

BACKGROUND

Sleep dysfunction (SD) is associated with a high symptom burden and lower neurocognitive performance after concussion and on baseline testing without injury. However, few studies have compared concussed athletes and controls with and without SD on clinical outcomes.

OBJECTIVE

To evaluate differences in clinical outcomes among both concussed athletes and matched controls with and without SD.

DESIGN

Retrospective cross-sectional study.

PARTICIPANTS

Participants aged 12 to 20 years were recruited from a concussion clinic (n = 50 patients) and research registry/flyers (n = 50 healthy age-/sex-matched controls). Participants were categorized by self-reported SD into one of 4 groups: sport-related concussion (SRC) + SD, SRC only, SD only, and controls.

MAIN OUTCOME MEASURES

Post-Concussion Symptom Scale (PCSS), Vestibular/Oculomotor Screening (VOMS), and neurocognitive testing (Immediate Postconcussion Assessment Cognitive Test).

RESULTS

Compared with the SRC only group, the SRC + SD group performed worse on all neurocognitive domains, had a higher total symptom score, and endorsed more symptoms on most VOMS items. In addition, the SRC + SD group was at an increased likelihood of having at least 1 abnormal VOMS item compared with SRC only group. The SRC only group had neurocognitive test scores and symptom reports statistically similar to the SD only group.

CONCLUSION

Sleep dysfunction after concussion is related to worse neurocognitive performance and higher concussion symptom reporting. This study extended findings to suggest vestibular symptomology is worse among athletes with SD after injury compared to injured athletes without SD. Similar performances on concussion assessments for the SRC only and SD only groups suggest SD may appear similar to clinical presentation of concussion, even at baseline in the absence of SRC.

Gaze stability in young adults with previous concussion history

BACKGROUND

Disruption of visual-vestibular interaction after concussion can cause gaze instability with head movements. The long-term impact of concussion on gaze stability is unknown.

OBJECTIVE

This cross-sectional comparative pilot study examined gaze stability in the chronic stage after concussion (greater than one year). A secondary objective was to examine the relationship between gaze stability and sleep.

METHODS

Outcome measures included: 1. Gaze stability in logMAR (mean loss of dynamic visual acuity (DVA) in the yaw and pitch planes); 2. Pittsburgh Sleep Quality Index (PSQI); 3. Epworth Sleepiness Scale (ESS). Post-Concussion Symptom Scale (PCSS), time since injury, and number of concussions were collected for the people with concussion.

RESULTS

The study sample included thirty-four adults (mean age 23.35±1.3 years). Seventeen had a history of 1-9 concussions, with a mean duration of 4.4±1.9 years since last concussion; and 17 were age and sex-matched controls. Mean pitch plane DVA loss was greater in the concussion group compared to the control group (p = 0.04). Participants with previous concussion had lower sleep quality based on the PSQI (p = 0.01) and increased daytime sleepiness based on the ESS (p = 0.01) compared to healthy controls. Mean DVA loss in the pitch plane was significantly correlated with the PSQI (r = 0.43, p = 0.01) and the ESS (r = 0.41, p = 0.02).

CONCLUSION

Significant differences in dynamic visual acuity may be found in young adults long after a concussion, compared with those who have no concussion history. Furthermore, loss of dynamic visual acuity was associated with poorer sleep quality and higher daytime sleepiness.

Connectome mapping with edge density imaging differentiates pediatric mild traumatic brain injury from typically developing controls: proof of concept

BACKGROUND

Although acute neurologic impairment might be transient, other long-term effects can be observed with mild traumatic brain injury. However, when pediatric patients with mild traumatic brain injury present for medical care, conventional imaging with CT and MR imaging often does not reveal abnormalities.

OBJECTIVE

To determine whether edge density imaging can separate pediatric mild traumatic brain injury from typically developing controls.

MATERIALS AND METHODS

Subjects were recruited as part of the "Therapeutic Resources for Attention Improvement using Neuroimaging in Traumatic Brain Injury" (TRAIN-TBI) study. We included 24 adolescents (χ=14.1 years of age, σ=1.6 years, range 10-16 years), 14 with mild traumatic brain injury (TBI) and 10 typically developing controls. Neurocognitive assessments included the pediatric version of the California Verbal Learning Test (CVLT) and the Attention Network Task (ANT). Diffusion MR imaging was acquired on a 3-tesla (T) scanner. Edge density images were computed utilizing fiber tractography. Principal component analysis (PCA) and support vector machines (SVM) were used in an exploratory analysis to separate mild TBI and control groups. The diagnostic accuracy of edge density imaging, neurocognitive tests, and fractional anisotropy (FA) from diffusion tensor imaging (DTI) was computed with two-sample t-tests and receiver operating characteristic (ROC) metrics.

RESULTS

Support vector machine-principal component analysis of edge density imaging maps identified three white matter regions distinguishing pediatric mild TBI from controls. The bilateral tapetum, sagittal stratum, and callosal splenium identified mild TBI subjects with sensitivity of 79% and specificity of 100%. Accuracy from the area under the ROC curve (AUC) was 94%. Neurocognitive testing provided an AUC of 61% (CVLT) and 71% (ANT). Fractional anisotropy yielded an AUC of 48%.

CONCLUSION

In this proof-of-concept study, we show that edge density imaging is a new form of connectome mapping that provides better diagnostic delineation between pediatric mild TBI and healthy controls than DTI or neurocognitive assessments of memory or attention.

Increased Risk of Musculoskeletal Injury Following Sport-Related Concussion: A Perception-Action Coupling Approach

Recent studies have concluded that athletes have increased risk of musculoskeletal injury following sport-related concussion. While an underlying explanation is still unknown, perceptual-motor control may be implicated in this increased risk. Some authors have purported that indirect perception (i.e., a "top-down" view of neuromuscular control) may be disrupted following sport-related concussion. Direct perception theory states that the athlete and environment are inextricably linked in a continuous perception-action coupling loop. That is, the athlete is able to directly perceive opportunities for action (e.g., "affordances") in the environment. Based on these notions, the aim of the current paper was to introduce a theoretical model that argues that sport-related concussion may dysregulate the direct perception process, potentially increasing behavioral risk of musculoskeletal injury during sport. Our model is integrated with a sport-related concussion clinical treatment model, which highlights individualized profiles that characterize the heterogeneous response to sport-related concussion. These profiles have a typical constellation of symptoms (e.g., anxiety, fatigue, ocular dysfunction, etc.), which themselves have been associated with disrupted perception-action coupling, independent of sport-related concussion. Therefore, we argue that athletes who have not re-established perception-action coupling loops following sport-related concussion may be at increased risk of subsequent musculoskeletal injury.

Concussion Symptom Cutoffs for Identification and Prognosis of Sports-Related Concussion: Role of Time Since Injury

BACKGROUND

Symptom reporting with scales such as the Post-Concussion Symptom Scale (PCSS) is one of the most sensitive markers of concussed status and/or recovery time, It is known that time from injury until initial clinic visit affects symptom presentation and recovery outcomes, but no study to date has evaluated changes in clinical cutoff scores for the PCSS based on earlier versus later clinical presentation postconcussion.

PURPOSE

To evaluate if time since injury after sports-related concussion (SRC) affects clinical cutoff scores for total PCSS and PCSS factors in differentiating athletes with SRC from healthy controls and predicting prolonged recovery (>30 days) after SRC.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A chart review was conducted of clinical data from patients with SRC (age, 13-25 years; n = 588; female, n = 299) who presented to concussion specialty clinics. Participants were categorized on the basis of time from injury: early (≤7 days; n = 348) and late (8-21 days; n = 240). Outcomes were total symptom severity (ie, total PCSS score) and total score for each of 4 symptom factors (cognitive/migraine/fatigue [CMF], affective, sleep, and somatic). Area under the curve (AUC) analyses were conducted using the Youden index to optimize sensitivity and specificity cutoffs.

RESULTS

In the early group, the CMF factor (cutoff, ≥7; AUC = 0.944), affective factor (cutoff, ≥1; AUC = 0.614), and total PCSS (cutoff, ≥7; AUC = 0.889) differentiated athletes with SRC from controls. In the late group, the CMF factor cutoff was reduced (cutoff, ≥4; AUC = 0.945), while the total PCSS score (cutoff, ≥7; AUC = 0.892), affective factor (cutoff, ≥1; AUC = 0.603), and sleep factor (cutoff, ≥1; AUC = 0.609) remained the same. In the early cohort, the CMF factor was the strongest predictor of protracted recovery (cutoff, ≥23; AUC = 0.717), followed by the total PCSS (cutoff, ≥39; AUC = 0.695) and affective factor (cutoff, ≥2; AUC = 0.614). The affective factor (cutoff, ≥1; AUC = 0.642) and total PCSS (cutoff, ≥35; AUC = 0.592) were significant predictors in the late cohort, but the cutoff threshold was reduced.

CONCLUSION

The findings indicate that PCSS symptom clinical cutoffs for identifying injury and recovery prognosis change on the basis of time since injury. Specifically, the combination of CMF, affective, and sleep factors is the best differentiator of athletes with SRC from controls regardless of time since injury. Furthermore, the CMF factor is the most robust predictor of prolonged recovery if the patient is within 1 week of SRC, whereas the affective factor is the most robust predictor of prolonged recovery if the patient is within 2 to 3 weeks of SRC.

Association of sleep symptoms with mood and vestibular subtypes following sport-related concussion

Sport-related concussion (SRC) is a heterogenous injury with diverse symptoms and impairments that can be aggregated into clinical subtypes (cognitive, headache/migraine, vestibular, ocular-motor, anxiety/mood). Sleep disruption has been defined as potential exacerbating conditions that may accompany the five clinical subtypes. The authors sought to better characterize the role of impaired sleep in each clinical subtype and to identify other risk factors for sleep impairment after SRC. 281 patients (15.3 ± 2.1 years) aged 10-22 years within 21 days of SRC completed the Post-Concussion Symptom Scale (PCSS), the Vestibular/Ocular Motor Screening (VOMS), and a clinical assessment to identify clinical subtype. Subjects were then divided into HIGH (≥7; n = 82) and LOW (≤3; n = 132) sleep symptom groups for comparison. HIGH participants had greater proportions of females (p < 0.001), history of psychiatric disorder (p < 0.001); total PCSS (p < 0.001); and impairment on all VOMS items (p < 0.001). HIGH participants were associated with mood/anxiety (p < 0.001), vestibular (p = 0.003) and ocular (p = 0.03) subtypes. Results of a logistic regression (LR) model with adjusted odds ratios (OR) to predict HIGH sleep symptoms supported anxiety/mood profile (OR = 2.98), vestibular profile (OR = 2.81), psychiatric history (OR = 4.99), and history of motion sickness (OR = 2.13) as significant predictors. Prescribing behavioral and sleep interventions may improve outcomes in cases where these factors co-occur.

Post-traumatic Headache After Pediatric Traumatic Brain Injury: Prevalence, Risk Factors, and Association With Neurocognitive Outcomes

Post-traumatic headache is common after pediatric traumatic brain injury and affects thousands of children every year, but little is known about how headache affects recovery after traumatic brain injury in other symptom domains. We aimed to determine the association between headache and other common symptoms after pediatric traumatic brain injury and explore whether subjective complaints of headache are associated with objective deficits on specialized neurocognitive testing. We conducted a retrospective cohort study of children ages 3-19 years following traumatic brain injury with a completed Sports Concussion Assessment Tool (SCAT) questionnaire. Post-traumatic headache was defined by a score more than 2 on the SCAT question for headache and define headache groups for comparison. In our cohort, we analyzed data from the Delis-Kaplan Executive Function System and the Wechsler Abbreviated Scale of Intelligence, Second Edition (WASI-II). Headache was reported in 40 (33%) patients presenting for post-traumatic brain injury care among 121 pediatric traumatic brain injury patients and did not differ by injury severity. Median total SCAT symptom score in the headache group was 5-fold higher compared to patients without headache (median 45.5 vs 9; P < .001). Significantly lower-scaled scores in color naming, matrix reasoning, letter sequencing, and letter switching were also found in the headache group (all P ≤ .03). Our study shows that headache, as reported by patients on the SCAT, is associated with higher symptom scores in all other symptom domains, including sleep, mood, sensory, and cognitive. Headache was also associated with worse objective neurocognitive measures and may identify patients who could benefit from specialized follow-up care and management.

Relationships between Post-Concussion Sleep and Symptom Recovery: A Preliminary Study

Post-concussion sleep disturbances can be debilitating and may influence days to symptom recovery; however, evidence is minimal. The purpose of this study was to explore relationships between days to symptom recovery and aspects of sleep, as measured by actigraphy and subjective sleep questionnaires in a concussed sample. Thirty-one college students were physician-diagnosed with a concussion and asked to complete a daily sleep symptom checklist. Participants (n = 14) were excluded based on lack of compliance/early termination (22.6%), recorded <5 nights of data (12.9%), and protracted recoveries (3.2%). Final concussed sample included 17 college-aged students (varsity student-athletes, n = 5; university students, n = 12). A wrist-worn ActiGraph GT9X Link was provided during initial evaluation (within 72 h post-injury) and worn continuously until symptom recovery (follow-up evaluation; 14.3 ± 5.9 days post-injury). The Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) also were completed at follow-up. Pearson's correlations were conducted to determine relationships between days to symptom recovery and actigraphy sleep outcomes (sleep onset latency, wake after sleep onset (WASO_norm), total sleep time, sleep efficiency (SE), and number of awakenings) across recovery stages (2-3 days post-injury, mid-point, and end). Spearman's rho correlations were used to determine relationships between subjective sleep (PSQI global), sleepiness (ESS total), and sleep cluster symptom severity and days to symptom recovery. At recovery mid-point, individuals who were awake longer throughout the night (24.1 ± 9.0%) and/or were less efficient at sleeping (73.7 ± 9.7%) took longer to recover (WASO_norm: r = 0.58, p = 0.015; SE: r = -0.51, p = 0.035). Poorer post-concussion sleep quality (based on PSQI) was correlated with longer recovery (r_s = 0.70, p = 0.001). Post-concussion sleep-wake disturbances at recovery mid-point and overall poorer sleep quality may be associated with longer symptom recovery. Our findings provide preliminary guidance on identifying those who may be at risk for longer recoveries based on poorer sleep post-injury.

Differences in sleep between concussed and nonconcussed college students: a matched case-control study

Study Objectives

To describe sleep 2-3 days postconcussion through symptom recovery and make comparison to well-matched nonconcussed controls.

Methods

Twenty college students were physician diagnosed with a concussion and compared with 20 nonconcussed controls matched on age, sex, physical activity, and sleep quality. A wrist-worn ActiGraph GT9X Link was provided during initial evaluation (within 72 hr postinjury for concussed) and worn continuously until symptom resolution (duration matched for nonconcussed). All participants completed a sleep symptom severity checklist, the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale (ESS). Separate 2(group) × 3(time points) mixed model ANOVAs were conducted to compare actigraphy sleep outcomes (sleep onset latency [SOL], normalized wake after sleep onset [WASOnorm], total sleep time [TST], sleep efficiency, and number of awakenings) across recovery stages (2-3 days postinjury, mid-point, and end of recovery). Intraindividual coefficient of variation was calculated for each sleep outcome. Mann-Whitney U tests compared PSQI global score, ESS total score, and sleep symptom severity between groups (α = 0.05).

Results

At 2-3 days postinjury, concussed individuals took longer to fall asleep compared with controls (p = 0.002). Greater intraindividual variability in WASOnorm (p = 0.017) and TST (p = 0.044) existed in concussed individuals across recovery. Poorer sleep quality (p < 0.001), excessive daytime sleepiness (p = 0.014), and worse sleep symptoms (p < 0.001) existed in concussed compared with controls.

Conclusions

Concussed individuals took longer to fall asleep 2-3 days postconcussion, experienced greater variation in sleep fragmentation and sleep time until symptom resolution, and reported worse sleep quality. Our preliminary findings may guide researchers interested in better understanding sleep postconcussion.

Preliminary Evidence for a Window of Increased Vulnerability to Sustain a Concussion in Females: A Brief Report

A difference exists between sexes for the incidence of concussion injuries and severity of post-injury outcomes with females having a higher incidence rate (in comparable sports) and experience more robust symptoms than males. The basis for this disparity has remained largely unresolved. Recent findings point to a potential biological mechanism that may be related to the menstrual cycle as an arbiter of post-injury outcomes. What has not been addressed, is whether the phase of menstrual cycle (inferred fluctuations of ovarian hormones) contributes to an increased vulnerability to sustain a concussion injury. This prospective, observational study sought to determine if concussions occurred at different frequencies throughout the phase of the menstrual cycle. Female athletes who sustained a concussion injury were queried three times over the 7-day study (e.g., within 48 h of injury, and 4 and 7 days after injury) to recall the number of days that have elapsed since the beginning of their most recent menstruation. Twenty female athletes enrolled after sustaining a concussion; 18 were eumenorrheic and 2 amenorrheic. Among eumenorrheic participants at the time of injury, 2 were in the follicular phase, 4 were in the early luteal phase and 9 were in the late luteal phase. Two athletes were injured on the first and 1 was injured on the second day of menstruation. The greatest number of concussions were sustained during the late luteal phase and during the first 2 days of menstruation. This 9-day window accounted for 2/3rd of the sustained concussions in our study.

Repeated mild traumatic brain injury can cause acute neurologic impairment without overt structural damage in juvenile rats

Repeated concussion is becoming increasingly recognized as a serious public health concern around the world. Moreover, there is a greater awareness amongst health professionals of the potential for repeated pediatric concussions to detrimentally alter the structure and function of the developing brain. To better study this issue, we developed an awake closed head injury (ACHI) model that enabled repeated concussions to be performed reliably and reproducibly in juvenile rats. A neurological assessment protocol (NAP) score was generated immediately after each ACHI to help quantify the cumulative effects of repeated injury on level of consciousness, and basic motor and reflexive capacity. Here we show that we can produce a repeated ACHI (4 impacts in two days) in both male and female juvenile rats without significant mortality or pain. We show that both single and repeated injuries produce acute neurological deficits resembling clinical concussion symptoms that can be quantified using the NAP score. Behavioural analyses indicate repeated ACHI acutely impaired spatial memory in the Barnes maze, and an interesting sex effect was revealed as memory impairment correlated moderately with poorer NAP score performance in a subset of females. These cognitive impairments occurred in the absence of motor impairments on the Rotarod, or emotional changes in the open field and elevated plus mazes. Cresyl violet histology and structural magnetic resonance imaging (MRI) indicated that repeated ACHI did not produce significant structural damage. MRI also confirmed there was no volumetric loss in the cortex, hippocampus, or corpus callosum of animals at 1 or 7 days post-ACHI. Together these data indicate that the ACHI model can provide a reliable, high throughput means to study the effects of concussions in juvenile rats.

Understanding the interplay between mild traumatic brain injury and cognitive fatigue: models and treatments

Nearly 2 million traumatic brain injuries occur annually, most of which are mild (mTBI). One debilitating sequela of mTBI is cognitive fatigue: fatigue following cognitive work. Cognitive fatigue has proven difficult to quantify and study, but this is changing, allowing models to be proposed and tested. Here, we review evidence for four models of cognitive fatigue, and relate them to specific treatments following mTBI. The evidence supports two models: cognitive fatigue results from the increased work/effort required for the brain to process information after trauma-induced damage; and cognitive fatigue results from sleep disturbances. While there are no evidence-based treatments for fatigue after mTBI, some pharmacological and nonpharmacological treatments show promise for treating this debilitating problem. Future work may target the role of genetics, neuroinflammation and the microbiome and their role in complex cognitive responses such as fatigue.

Post-Concussive Syndrome: a Focus on Post-Traumatic Headache and Related Cognitive, Psychiatric, and Sleep Issues

PURPOSE OF REVIEW

Post-traumatic headache (PTH) is a secondary headache disorder following traumatic brain injury. We sought to examine the recent literature on PTH and associated cognitive, psychiatric, and sleep conditions to understand the latest findings about the associated conditions and available screening tools, and to understand the available treatment options for PTH.

RECENT FINDINGS

Up to one third of PTH patients may have depression and about one quarter may have insomnia. Anxiety and cognitive issues are also common. While there are few studies examining abortive medications for PTH, recent studies of preventive medications examine the efficacy of topiramate, and topiramate may be better than other oral preventive medications. Other currently investigated treatments include nerve blocks, onabotulinum toxin A, transmagnetic stimulation, and behavioral therapy (biofeedback). Due to an expanded focus on and knowledge of concussion and PTH, comorbid psychiatric, cognitive, and sleep issues have become more widely acknowledged and studied. However, more high-quality studies must be conducted to examine the underlying pathophysiology of PTH and associated symptoms and to determine the most effective abortive and preventive treatment options.

Post-traumatic headache: the use of the sport concussion assessment tool (SCAT-3) as a predictor of post-concussion recovery

BACKGROUND

Given that post-traumatic headache is one of the most prevalent and long-lasting post-concussion sequelae, causes significant morbidity, and might be associated with slower neurocognitive recovery, we sought to evaluate the use of concussion screening scores in a concussion clinic population to assess for post-traumatic headache.

METHODS

This is a retrospective cross-sectional study of 254 concussion patients from the New York University (NYU) Concussion Registry. Data on the headache characteristics, concussion mechanism, concussion screening scores were collected and analyzed.

RESULTS

72% of the patients had post-traumatic headache. About half (56.3%) were women. The mean age was 35 (SD 16.2). 90 (35%) patients suffered from sport-related concussions (SRC). Daily post-traumatic headache patients had higher Sport Concussion Assessment Tool (SCAT)-3 symptom severity scores than the non-daily post-traumatic headache and the headache-free patients (50.2 [SD 28.2] vs. 33.1 [SD 27.5] vs. 21.6 SD23], p < 0.001). Patients with SRC had lower headache intensity (4.47 [SD 2.5] vs. 6.24 [SD 2.28], p < 0.001) and SCAT symptom severity scores (33.9 [SD 27.4] vs. 51.4 [SD 27.7], p < 0.001) than the other patients, but there were no differences in post-traumatic headache prevalence, frequency, and Standardized Assessment of Concussion (SAC) scores.

CONCLUSION

The presence and frequency of post-traumatic headache are associated with the SCAT-3 symptom severity score, which is the most important predictor for post-concussion recovery. The SCAT-3 symptom severity score might be a useful tool to help characterize patients' post-traumatic headache.

Sleep Disorders Associated With Traumatic Brain Injury-A Review

BACKGROUND

Sleep disorders are common are common following traumatic brain injury.

METHODS

In this article we review the spectrum and proposed mechanisms of traumatic brain injury associated sleep disorders and discuss the clinical approach to diagnosis and management of these disorders.

RESULT

Disordered sleep and wakefulness after traumatic brain injury is common. Sleep disruption contributes to morbidity, such as the development of neurocognitive and neurobehavioral deficits, and prolongs the recovery phase after injury. Early recognition and correction of these problems may limit the secondary effects of traumatic brain injury and improve patient outcomes.

CONCLUSION

Evaluating sleep disorders in traumatic brain injury should be an important component of post-traumatic brain injury assessment and management.