A double-blind, placebo-controlled intervention trial of 3 and 10 mg sublingual melatonin for post-concussion syndrome in youths (PLAYGAME): study protocol for a randomized controlled trial

Matrix Metalloproteinase-9 inhibitors as therapeutic drugs for traumatic brain injury

Traumatic brain injury (TBI) is one of the leading causes of morbidity and mortality among young adults and the elderly. In the United States, TBI is responsible for around 30 percent of all injuries brought on by injuries in general. Vasogenic cerebral edema due to blood-brain barrier (BBB) dysfunction and the associated elevation of intracranial pressure (ICP) are some of the major causes of secondary injuries following traumatic brain injury. Matrix metalloproteinase-9 (MMP-9) is a therapeutic target for being an enzyme that degrades the proteins that make up a part of the microvascular basal lamina as well as inter-endothelial tight junctions of the blood-brain barrier. MMP-9-mediated BBB dysfunctions and the compromise of the BBB is a major pathway that leads the development of vasogenic cerebral edema, elevation of ICP, poor cerebral perfusion and brain herniation following traumatic brain injury. That makes MMP-9 an effective therapeutic target and endogenous or exogenous MMP-9 inhibitors as therapeutic drugs for preventing secondary brain damage after traumatic brain injury. Although our understanding of the mechanisms that underlie the primary and secondary stages of damage following a TBI has significantly improved in recent years, such information has not yet resulted in the successful development of novel pharmacological treatment options for traumatic brain injury. Recent pre-clinical and/or clinical studies have demonstrated that there are several compounds with specific or non-specific MMP-9 inhibitory properties either directly binding and inhibiting MMP-9 or by indirectly inhibiting MMP-9, with potential as therapeutic agents for traumatic brain injury. This article reviews the efficacy of several such medications and potential agents that include endogenous and exogeneous compounds that are at various levels of research and development. MMP-9-based therapeutic drug development has enormous potential in the pharmacological treatment of cerebral edema and/or neuronal injury resulting from traumatic brain injury.

Evidence of Ongoing Cerebral Microstructural Reorganization in Children With Persisting Symptoms Following Mild Traumatic Brain Injury: A NODDI DTI Analysis

Approximately 300-550 children per 100,000 sustain a mild traumatic brain injury (mTBI) each year, of whom ∼25-30% have long-term cognitive problems. Following mTBI, free water (FW) accumulation occurs in white matter (WM) tracts. Diffusion tensor imaging (DTI) can be used to investigate structural integrity following mTBI. Compared with conventional DTI, neurite orientation dispersion and density imaging (NODDI) orientation dispersion index (ODI) and fraction of isolated free water (FISO) metrics may allow a more advanced insight into microstructural damage following pediatric mTBI. In this longitudinal study, we used NODDI to explore whole-brain and tract-specific differences in ODI and FISO in children with persistent symptoms after mTBI (n = 80) and in children displaying clinical recovery (n = 32) at 1 and 2-3 months post-mTBI compared with healthy controls (HCs) (n = 21). Two-way repeated measures analysis of variance (ANOVA) and voxelwise two-sample t tests were conducted to compare whole-brain and tract-specific diffusion across groups. All results were corrected at positive false discovery rate (pFDR) <0.05. We also examined the association between NODDI metrics and clinical outcomes, using logistical regression to investigate the value of NODDI metrics in predicting future recovery from mTBI. Whole-brain ODI was significantly increased in symptomatic participants compared with HCs at both 1 and 2 months post-injury, where the uncinate fasciculus (UF) and inferior fronto-occipital fasciculus (IFOF) were particularly implicated. Using region of interest (ROI) analysis in significant WM, bilateral IFOF and UF voxels, symptomatic participants had the highest ODI in all ROIs. ODI was lower in asymptomatic participants, and HCs had the lowest ODI in all ROIs. No changes in FISO were found across groups or over time. WM ODI was moderately correlated with a higher youth-reported post-concussion symptom inventory (PCSI) score. With 87% predictive power, ODI (1 month post-injury) and clinical predictors (age, sex, PCSI score, attention scores) were a more sensitive predictor of recovery at 2-3 months post-injury than fractional anisotropy (FA) and clinical predictors, or clinical predictors alone. FISO could not predict recovery at 2-3 months post-injury. Therefore, we found that ODI was significantly increased in symptomatic children following mTBI compared with HCs at 1 month post-injury, and progressively decreased over time alongside clinical recovery. We found no significant differences in FISO between groups or over time. WM ODI at 1 month was a more sensitive predictor of clinical recovery at 2-3 months post-injury than FA, FISO, or clinical measures alone. Our results show evidence of ongoing microstructural reorganization or neuroinflammation between 1 and 2-3 months post-injury, further supporting delayed return to play in children who remain symptomatic. We recommend future research examining the clinical utility of NODDI following mTBI to predict recovery or persistence of post-concussion symptoms and thereby inform management of mTBI.

Melatonin attenuates sevoflurane-induced hippocampal damage and cognitive deficits in neonatal mice by suppressing CypD in parvalbumin neurons

BACKGROUND

Sevoflurane, a commonly administered inhaled anesthetic, is found to induce synaptic and mitochondrial damage in neonatal mice. Mitochondrial membrane potential (MMP) changes, mediated by Cyclophilin D (CypD), are implicated in mitochondrial function. Melatonin, known for its significant neuroprotective properties, was investigated in this study to elucidate its mechanisms in mitigating the cognitive impairment caused by sevoflurane.

METHODS

The mice were categorized into several groups, including the control, vehicle, sevoflurane, vehicle plus sevoflurane, and melatonin plus sevoflurane groups. From postnatal day 6 to day 8, the mice were administered inhaled sevoflurane or intraperitoneal melatonin. MMP and reactive oxygen species (ROS) were measured using appropriate detection kits. The protein expression levels of PSD95, Synapsin Ⅰ, and CypD in the hippocampus were analyzed through western blotting in acute and prolonged terms. Immunofluorescence staining was used to assess the co-localizations of PSD95 or CypD in parvalbumin (PV) neurons. Cognitive ability was evaluated through novel object recognition, social interaction experiment, and the Morris water maze.

RESULTS

The findings revealed that repeated exposure to sevoflurane in neonatal mice resulted in cognitive and synaptic impairment. Furthermore, melatonin administration suppressed the ROS and CypD protein expression, enhanced the MMP in mitochondria and synaptic protein expression in PV neurons, and ameliorated cognitive deficits.

CONCLUSION

Melatonin alleviated sevoflurane-induced cognitive deficits by suppressing CypD and promoting synaptic development in hippocampal PV neurons. These results provide valuable insights into a promising therapeutic approach for preventing neurotoxic injuries caused by general anesthetics.

Traumatic Brain Injury, Sleep, and Melatonin-Intrinsic Changes with Therapeutic Potential

Traumatic brain injury (TBI) is one of the most prevalent causes of morbidity in the United States and is associated with numerous chronic sequelae long after the point of injury. One of the most common long-term complaints in patients with TBI is sleep dysfunction. It is reported that alterations in melatonin follow TBI and may be linked with various sleep and circadian disorders directly (via cellular signaling) or indirectly (via free radicals and inflammatory signaling). Work over the past two decades has contributed to our understanding of the role of melatonin as a sleep regulator and neuroprotective anti-inflammatory agent. Although there is increasing interest in the treatment of insomnia following TBI, a lack of standardization and rigor in melatonin research has left behind a trail of non-generalizable data and ambiguous treatment recommendations. This narrative review describes the underlying biochemical properties of melatonin as they are relevant to TBI. We also discuss potential benefits and a path forward regarding the therapeutic management of TBI with melatonin treatment, including its role as a neuroprotectant, a somnogen, and a modulator of the circadian rhythm.

Neuro-Inflammation Modulation and Post-Traumatic Brain Injury Lesions: From Bench to Bed-Side

Head trauma is the most common cause of disability in young adults. Known as a silent epidemic, it can cause a mosaic of symptoms, whether neurological (sensory-motor deficits), psychiatric (depressive and anxiety symptoms), or somatic (vertigo, tinnitus, phosphenes). Furthermore, cranial trauma (CT) in children presents several particularities in terms of epidemiology, mechanism, and physiopathology-notably linked to the attack of an immature organ. As in adults, head trauma in children can have lifelong repercussions and can cause social and family isolation, difficulties at school, and, later, socio-professional adversity. Improving management of the pre-hospital and rehabilitation course of these patients reduces secondary morbidity and mortality, but often not without long-term disability. One hypothesized contributor to this process is chronic neuroinflammation, which could accompany primary lesions and facilitate their development into tertiary lesions. Neuroinflammation is a complex process involving different actors such as glial cells (astrocytes, microglia, oligodendrocytes), the permeability of the blood-brain barrier, excitotoxicity, production of oxygen derivatives, cytokine release, tissue damage, and neuronal death. Several studies have investigated the effect of various treatments on the neuroinflammatory response in traumatic brain injury in vitro and in animal and human models. The aim of this review is to examine the various anti-inflammatory therapies that have been implemented.

Sleep Problems and Melatonin Prescription After Concussion Among Youth Athletes

OBJECTIVES

To examine the effect of sleep disturbances on concussion symptom recovery and to examine the effect of melatonin prescription on symptom improvement among concussed adolescents with sleep problems.

DESIGN

Longitudinal test-retest.

SETTING

Sports medicine clinic.

PARTICIPANTS

Patients aged 8 to 18 years, diagnosed with a concussion, evaluated within 14 days after injury, and evaluated again 15 to 35 days after injury.

INDEPENDENT VARIABLES

We grouped patients based on whether they reported sleep disturbances within 14 days of injury.

MAIN OUTCOME MEASURES

Outcome measures included symptom severity, headache severity, melatonin prescription, and the change in symptom severity between visits.

RESULTS

Two hundred twenty-five patients were included: 36% who reported sleep problems (44% female; age = 14.4 ± 2.0 years; evaluated 7.3 ± 3.8 and 23.2 ± 5.4 days after injury) and 64% who did not (32% female; age = 14.6 ± 2.3 years; evaluated 7.2 ± 3.4 and 23.0 ± 5.3 days after injury). Those with sleep problems reported higher symptom severity than those without across the 2 visits (22.1 ± 14.3 vs 14.6 ± 12.5; P < 0.001). There was no significant difference in the change in symptom severity between visits among those who received [median = 9-point improvement; interquartile range (IQR) = 1-14] and did not (median = 9, IQR = 2-18) receive a melatonin prescription (P = 0.80).

CONCLUSIONS

Sleep problems among pediatric patients within 2 weeks of concussion are associated with more severe symptoms. Melatonin prescription was not associated with faster symptom recovery.

Changes in working memory-related cortical responses following pediatric mild traumatic brain injury: A longitudinal fMRI study

Persistent post-concussion symptoms (PPCS) lasting longer than 4 weeks affect 25% of children with mild traumatic brain injury (mTBI) or concussion. Working memory (WM) problems are a common complaint in children with PPCS. Despite normal function on traditional neuropsychological tests, these children exhibit aberrant cortical responses within the dorsolateral prefrontal cortex (dlPFC) and default mode network (DMN) regions – both of which are implicated in WM. Using a prospective, longitudinal cohort study design, we investigated changes in cortical fMRI responses within the dlPFC and DMN during an nback WM task at two timepoints: one and two months post-injury. Across these timepoints, the primary outcome was change in cortical activations (increase in BOLD) and deactivations (decrease in BOLD) of both dlPFC and DMN. Twenty-nine children (mean age 15.49 ± 2.15; 48.3% male) with fMRI scans at both timepoints were included, following data quality control. Student’s t-tests were used to examine cortical activations across time and task difficulty. ANCOVA F-tests examined cortical responses after removal of baseline across time, task difficulty and recovery. Volumes of interest (5 mm sphere) were placed in peak voxel regions of the DMN and dlPFC to compare cortical responses between recovered and unrecovered participants over time (one-way ANOVA). Between one and two months post-injury, we found significant increases in dlPFC activations and significant activations and deactivations in the DMN with increasing task difficulty, alongside improved task performance. Cortical responses of the DMN and bilateral dlPFC displayed increased intensity in recovered participants, together with improved attention and behavioural symptoms. Overall, our findings suggest evidence of neural compensation and ongoing cognitive recovery from pediatric TBI over time between one and two months post injury in children with PPCS. These results highlight the wider and persisting implications of mTBI in children, whose maturing brains are particularly vulnerable to TBI.

Factor analysis of the adolescent version of the behavioural assessment screening tool (BAST-A) in adolescents with concussion

Objective: Develop and validate the Behavioral Assessment Screening Tool for Adolescents with brain injury.Setting: Concussion clinicsParticipants: Adolescents with mild traumatic brain injury 3 months after initial concussion clinic visit (n = 138).Design: Assessment development and validation (cross-sectional cohort) studyMain Measures: Behavioral Assessment Screening Tool - AdolescentResults: Expert panel members added or modified items specific to adolescents to the original Behavioral Assessment Screening Tool for adults. The Content Validity Index was 97.2%. Exploratory factor analysis of the Behavioral Assessment Screening Tool - Adolescent reduced the initial 70 items to 46 primary items with a 3-factor solution: Negative Affect & Fatigue, Executive & Social Function, and Risk Behaviors. Internal consistency reliabilities ranged from good to excellent for all factors (Cronbach's α =.80-.95). We retained four secondary maladaptive coping items (from an initial six), though these require further modification and testing (Cronbach's α =.67).Conclusion: The Behavioral Assessment Screening Tool for Adolescents, a measure of neurobehavioral symptoms after mild traumatic brain injury in adolescents, has a multidimensional factor structure with evidence of good internal consistency reliabilities. Future work will further evaluate its convergent and discriminant validity and employ item response theory analyses for validation in a new sample of adolescents with concussion.

Efficacy of Melatonin for Sleep Disturbance in Children with Persistent Post-Concussion Symptoms: Secondary Analysis of a Randomized Controlled Trial

Sleep disturbances are commonly reported in children with persistent post-concussion symptoms (PPCS). Melatonin treatment is often recommended, yet supporting evidence is scarce. We aimed to evaluate the efficacy of treatment with melatonin for sleep disturbance in youth with PPCS following mild traumatic brain injury (mTBI). This article is a secondary analysis of a clinical trial of melatonin compared with placebo to treat PPCS. Youth (8-18 years of age) with PPCS and significant sleep-related problems (SRPs) at 4-6 weeks post-injury were eligible. Exclusion criteria: significant medical/psychiatric history; previous concussion/mTBI within 3 months. Treatment groups were: placebo, melatonin 3 mg, or melatonin 10 mg. Primary outcome was change in SRPs measured using the Post-Concussion Symptom Inventory (PCSI) after 2 weeks of treatment. Secondary outcomes included change in actigraphy sleep efficiency, duration, onset latency, and wake-after-sleep-onset. Behavior was measured using Behaviour Assessment for Children (2nd edition). Seventy-two participants (mean age 14.0, standard deviation [SD] = 2.6) years; 60% female) with PPCS and significant sleep disturbance were included in the secondary analysis: placebo (n = 22); melatonin 3 mg (n = 25); melatonin 10 mg (n = 25). Sixty-four participants had actigraphy data. SRPs decreased across all groups over time with a significant effect of melatonin 3 mg (3.7; 95% confidence interval [CI]: 2.1, 5.4) compared with placebo (7.4; 95% CI: 4.2, 10.6) and melatonin 10 mg (6.4; 95% CI: 3.6, 9.2). Sleep duration increased in the melatonin 3 mg (43 min; 95% CI: 6, 93) and melatonin 10 mg groups (55 min; 95% CI: 5, 104) compared with placebo. A per protocol analysis demonstrated improved sleep efficiency in the melatonin 10 mg group (p = 0.029). No serious adverse events were reported. Depressive symptoms significantly decreased with melatonin 3 mg (-4.7; 95% CI: -9.2, -.2) but not with melatonin 10 mg (-1.4, 95% CI: -5.9, 3.2) treatment compared with placebo. Changes in cognition or behavior were otherwise not significantly different between treatment groups. Short-term melatonin is a well-tolerated treatment for sleep disturbance in youth with PPCS following mTBI. In this context, it may also be associated with a reduction in depressive symptoms.

Revisiting Traumatic Brain Injury: From Molecular Mechanisms to Therapeutic Interventions

Studying the complex molecular mechanisms involved in traumatic brain injury (TBI) is crucial for developing new therapies for TBI. Current treatments for TBI are primarily focused on patient stabilization and symptom mitigation. However, the field lacks defined therapies to prevent cell death, oxidative stress, and inflammatory cascades which lead to chronic pathology. Little can be done to treat the mechanical damage that occurs during the primary insult of a TBI; however, secondary injury mechanisms, such as inflammation, blood-brain barrier (BBB) breakdown, edema formation, excitotoxicity, oxidative stress, and cell death, can be targeted by therapeutic interventions. Elucidating the many mechanisms underlying secondary injury and studying targets of neuroprotective therapeutic agents is critical for developing new treatments. Therefore, we present a review on the molecular events following TBI from inflammation to programmed cell death and discuss current research and the latest therapeutic strategies to help understand TBI-mediated secondary injury.

Evaluation of current post-concussion protocols

The growing number of concussions and mild traumatic brain injuries (mTBI) with the lack of evidence-based treatment options is a continuous health concern. This creates problems when evaluating and providing efficacious symptom management to patients suffering from post-concussion syndrome (PCS). Numerous pharmacological and non-pharmacological agents have been utilized in an attempt to treat PCS. Some of these approaches include physical therapy, analgesics, antidepressants, and nutraceuticals. Although these treatments have had some success, there has been inconsistent outcomes, with some examples of patients' symptoms worsening. Among pharmaceutical agents, fluoxetine has been a popular choice for the symptom management of PCS. Although some patients have had symptom resolution with the use of fluoxetine, there is still a lack of conclusive data. Of the several biochemical changes that occur in a patient's brain following a concussion, an increase in reactive oxygen species (ROS) is of particular concern. In order to counteract the responses of the brain, antioxidants, such as ascorbic acid, have been utilized to reverse the damaging cellular effects. However, this may inadvertently cause an increase in ROS, rather than a reduction. Although there is a lack of consistency in exactly when each treatment was used in the post-injury interval, it is important that we analyze the strengths and weaknesses of the most commonly used agents due to the lack of a set protocol. The studies were chosen in a non-exhaustive manner and were not consistent in patients' post-injury intervals, in addition to other baseline characteristics. However, over-arching claims that some treatments may benefit more than others can be made. This review evaluates both the pharmaceutical and non-pharmaceutical protocols that are most commonly utilized in post-concussive patients for their efficacy in treatment of post-concussive syndrome (PCS).

Functional magnetic resonance imaging study of working memory several years after pediatric concussion

PRIMARY OBJECTIVE

The neurophysiological effects of pediatric concussion several years after injury remain inadequately characterized. The objective of this study was to determine if a history of concussion was associated with BOLD response differences during an n-back working memory task in youth.

RESEARCH DESIGN

Observational, cross-sectional.

METHODS AND PROCEDURES

Participants include 52 children and adolescents (M = 15.1 years, 95%CI = 14.4-15.8, range = 9-19) with past concussion (n = 33) or orthopedic injury (OI; n = 19). Mean time since injury was 2.5 years (95%CI = 2.0-3.0). Measures included postconcussion symptom ratings, neuropsychological testing, and blood-oxygen-dependent-level (BOLD) functional magnetic resonance imaging (fMRI) during an n-back working memory task.

MAIN OUTCOMES AND RESULTS

Groups did not differ on accuracy or speed during the three n-back conditions. They also did not differ in BOLD signal change for the 1- vs. 0-back or 2- vs. 0-back contrasts (controlling for task performance).

CONCLUSIONS

This study does not support group differences in BOLD response during an n-back working memory task in youth who are on average 2.5 years post-concussion. The findings are encouraging from the perspective of understanding recovery after pediatric concussion.

Sleep Symptoms Predict School Attendance After Pediatric Concussion

This study examined the relationship between postconcussive symptom domain and school attendance. Retrospective chart review was completed for 88 children aged 6 to 18 years who were evaluated within 30 days postinjury. Hierarchical multiple regression was used to assess the association of physical, cognitive, emotional, and sleep symptoms with extent of school attendance. A subgroup multiple regression analysis was conducted to evaluate whether age affected the relationship of symptoms to school attendance. After controlling for demographic variables and total number of symptoms, a higher number of postconcussive sleep symptoms strongly predicted less school attendance. Specifically, older children (≥14 years old) with more sleep symptoms demonstrated less school attendance. For children presenting for specialty care after concussion, sleep symptoms are unfavorably associated with return to school. Future work aimed at optimizing sleep regulation following concussion may assist with early reengagement in school as recommended by current concussion management guidelines.

Efficacy of Melatonin in Children With Postconcussive Symptoms: A Randomized Clinical Trial

BACKGROUND

Approximately 25% of children with concussion have persistent postconcussive symptoms (PPCS) with resultant significant impacts on quality of life. Melatonin has significant neuroprotective properties, and promising preclinical data suggest its potential to improve outcomes after traumatic brain injury. We hypothesized that treatment with melatonin would result in a greater decrease in PPCS symptoms when compared with a placebo.

METHODS

We conducted a randomized, double-blind trial of 3 or 10 mg of melatonin compared with a placebo (NCT01874847). We included youth (ages 8-18 years) with PPCS at 4 to 6 weeks after mild traumatic brain injury. Those with significant medical or psychiatric histories or a previous concussion within the last 3 months were excluded. The primary outcome was change in the total youth self-reported Post-Concussion Symptom Inventory score measured after 28 days of treatment. Secondary outcomes included change in health-related quality of life, cognition, and sleep.

RESULTS

Ninety-nine children (mean age: 13.8 years; SD = 2.6 years; 58% girls) were randomly assigned. Symptoms improved over time with a median Post-Concussion Symptom Inventory change score of -21 (95% confidence interval [CI]: -16 to -27). There was no significant effect of melatonin when compared with a placebo in the intention-to-treat analysis (3 mg melatonin, -2 [95% CI: -13 to 6]; 10 mg melatonin, 4 [95% CI: -7 to 14]). No significant group differences in secondary outcomes were observed. Side effects were mild and similar to the placebo.

CONCLUSIONS

Children with PPCS had significant impairment in their quality of life. Seventy-eight percent demonstrated significant recovery between 1 and 3 months postinjury. This clinical trial does not support the use of melatonin for the treatment of pediatric PPCS.

Default mode network anatomy and function is linked to pediatric concussion recovery

Objective

To determine whether anatomical and functional brain features relate to key persistent post–concussion symptoms (PPCS) in children recovering from mild traumatic brain injuries (mTBI), and whether such brain indices can predict individual recovery from PPCS.

Methods

One hundred and ten children with mixed recovery following mTBI were seen at the concussion clinic at Neurology department Alberta Children’s Hospital. The primary outcome was the Post–Concussion Symptom Inventory (PCSI, parent proxy). Sleep disturbance scores (PCSI subdomain) and the Neurocognition Index (CNS Vital Signs) were also measured longitudinally. PPCS was assessed at 4 weeks postinjury and 8–10 weeks postinjury. Gray matter volumes were assessed using magnetic resonance imaging (MRI) and voxel‐based morphometry at 4 weeks postinjury. Functional connectivity was estimated at the same timepoint using resting‐state MRI. Two complementary machine learning methods were used to assess if the combination of gray matter and functional connectivity indices carried meaningful prognostic information.

Results

Higher scores on a composite index of sleep disturbance, including fatigue, were associated with converging decreases in gray matter volume and local functional connectivity in two key nodes of the default mode network: the posterior cingulate cortex and the medial prefrontal cortex. Sleep‐related disturbances also significantly correlated with reductions in functional connectivity between these brain regions. The combination of structural and functional brain indices associated to individual variations in the default mode network accurately predicted clinical outcomes at follow‐up (area under the curve = 0.86).

Interpretation

These results highlight that the function–structure profile of core default mode regions underpins sleep‐related problems following mTBI and carries meaningful prognostic information for pediatric concussion recovery.

Practice Current: How do you diagnose and treat post-concussive headache?

A common complaint after concussion is the development of new or worsening headaches which can make it difficult or even impossible for patients to work or function in their day-to-day lives. Uncertainties associated with the complaints and a wide variety of approaches exist regarding the appropriate work-up and management of these patients. Areas of ongoing debate include the need for neuroimaging; optimal, acute, and preventative treatment; and proper counseling and expectation management. Given the wide variety of potential approaches and the lack of consensus, we sought expert opinion from around the globe on how to evaluate and manage patients with headache following concussion. Similar questions were posed to the rest of our readership in an online survey (links.lww.com/CPJ/A96), the results of which are also presented.

Longitudinal Assessment of Cortical Excitability in Children and Adolescents With Mild Traumatic Brain Injury and Persistent Post-concussive Symptoms

Introduction: Symptoms following a mild traumatic brain injury (mTBI) usually resolve quickly but may persist past 3 months in up to 15% of children. Mechanisms of mTBI recovery are poorly understood, but may involve alterations in cortical neurophysiology. Transcranial Magnetic Stimulation (TMS) can non-invasively investigate such mechanisms, but the time course of neurophysiological changes in mTBI are unknown. Objective/Hypothesis: To determine the relationship between persistent post-concussive symptoms (PPCS) and altered motor cortex neurophysiology over time. Methods: This was a prospective, longitudinal, controlled cohort study comparing children (8-18 years) with mTBI (symptomatic vs. asymptomatic) groups to controls. Cortical excitability was measured using TMS paradigms at 1 and 2 months post injury. The primary outcome was the cortical silent period (cSP). Secondary outcomes included short interval intracortical inhibition (SICI) and facilitation (SICF), and long-interval cortical inhibition (LICI). Generalized linear mixed model analyses were used to evaluate the effect of group and time on neurophysiological parameters. Results: One hundred seven participants (median age 15.1, 57% female) including 78 (73%) with symptomatic PPCS and 29 with asymptomatic mTBI, were compared to 26 controls. Cortical inhibition (cSP and SICI) was reduced in the symptomatic group compared to asymptomatic group and tended to increase over time. Measures of cortical facilitation (SICF and ICF) were increased in the asymptomatic group and decreased over time. TMS was well tolerated with no serious adverse events. Conclusions: TMS-assessed cortical excitability is altered in children following mild TBI and is dependent on recovery trajectory. Our findings support delayed return to contact sports in children even where clinical symptoms have resolved.

Microstructural neuroimaging of white matter tracts in persistent post-concussion syndrome: A prospective controlled cohort study

INTRODUCTION

Children with mild traumatic brain injury (mTBI) typically recover quickly, however approximately 15% experience persistent post-concussive symptoms (PPCS) past 3 months. The microstructural pathology associated with underlying persistent symptoms is poorly understood but is suggested to involve axonal injury to white matter tracts. Diffusion tensor imaging (DTI) can be used to visualize and characterize damage to white matter microstructure of the brain.

OBJECTIVE

We aimed to investigate white matter microstructure in children with persistent concussive symptoms as compared to typically developing controls, alongside evaluating differences in white matter changes over time and how this relates to symptom recovery.

METHODS

The current study is a prospective, longitudinal, controlled cohort study of children with mTBI. 104 children aged 8 to 18 years with a mTBI (72 symptomatic; 32 asymptomatic) were recruited from the Alberta Children's Hospital and compared to 20 healthy controls. Microstructural evidence of white matter injury was evaluated using DTI one month post injury and repeated 4 to 6 weeks later. Primary outcomes included fractional anisotropy and mean diffusivity of the corticospinal tracts, uncinate fasciculi, and motor fibers of the corpus callosum. Post-concussive symptoms were also measured using the Post-Concussion Symptom Inventory (PCSI) taken at both time points.

RESULTS

Fractional anisotropy of the left uncinate fasciculi was lower in symptomatic children compared to controls (F(2,119) = 3.582, p = 0.031). No other significant differences were observed.

CONCLUSIONS

Our findings provide evidence of microstructural injury following mTBI in children with ongoing post-concussive symptoms one month post injury. The changes were persistent 4-6 weeks later. Further longitudinal studies of white matter microstructure in PPCS will be helpful to clarify whether these white matter alterations resolve over time.

Nurse practitioners' recommendations for pharmacotherapy in the management of adolescent concussion

BACKGROUND AND PURPOSE

Nurse practitioners (NPs) frequently treat acute conditions presenting in children and adolescents in the outpatient setting. No evidence-based guidance exists pertaining to the treatment of concussion with medications. The purpose of this study was to examine recommendations by NPs for pharmacotherapy of acute symptoms for adolescent concussion.

METHODS

This is a secondary analysis of data from a web-based census survey of all licensed NPs in Oregon and Washington State, where they practice as independent providers with prescriptive authority. Based on a standardized adolescent patient scenario video, NPs were asked to indicate prescription or nonprescription medication recommendations for concussion symptoms. Open-ended descriptions of medication recommendations were coded, summarized, and described.

CONCLUSIONS

In narrative text, 78.4% of the 991 respondents recommended at least one type of prescription or nonprescription medication. Prescription medications (recommended by 17.2%) included antiemetics and antimigraine medications; nonprescription medications (recommended by 75.5%) included nonsteroidal anti-inflammatory drugs, over-the-counter pain relievers, and herbal medications. Pharmacotherapy recommendations varied by NP practice setting and rurality.

IMPLICATIONS FOR PRACTICE

Nurse practitioners have full prescriptive authority in many states. No guidelines inform medication use in managing acute concussion symptoms, yet many providers recommend their use.

Posttraumatic headache in pediatrics: an update and review

PURPOSE OF REVIEW

Headache following concussion and mild traumatic brain injury is very common in pediatrics. There is significant concern about appropriate management of acute and persistent headache following mild head injuries in children among affected youth, their families and care providers.

RECENT FINDINGS

The current article will review definitions and diagnoses of posttraumatic headache (PTHA), recent research regarding risk factors for persistence of postconcussion symptoms and headaches, current recommendations for the evaluation of youth with PTHA, recent data regarding efficacy of treatment options for PTHA, and current recommendations for the treatment of acute and persistent PTHA.

SUMMARY

PTHA is common following concussion in pediatrics. Some of the most consistent risk factors for persistent symptoms following concussion include female sex, adolescent age, prior concussion with prolonged recovery, prior headache history and high number of acute symptoms, particularly migrainous symptoms, following concussion. There are few prospective studies of the treatment of PTHA in pediatrics; however, a recent study found that short-term use of ibuprofen for those with acute PTHA following concussion may be associated with lower risk of symptoms and better function 1 week after injury. Currently complete rest or cocooning following concussion is not recommended as it may actually be associated with longer recovery time; a gradual return to cognitive and physical activity appears to be most effective strategy but more study is needed.

Managing Sports-related Concussions From Time of Injury Through Return to Play

Sports-related concussions continue to generate widespread interest. A concussion is a complex pathophysiologic process, with or without loss of consciousness, that results in a disturbance of brain function. Risk factors include age <18 years, female sex, and history of a previous concussion. A sideline physical examination with standardized assessment tools can assist diagnosis. Management for suspected concussion begins with immediate removal from play and requires clinical follow-up. Symptoms are usually self-limited and resolve within 2 to 3 weeks. Initial treatment consists of a reduction in cognitive activity and physical rest. A stepwise return-to-play protocol, taking into consideration state laws, with a gradual increase in activity until the athlete is able to perform full activity without symptoms should be followed. Neuropsychologic testing may be used as a tool in management. For prolonged concussion, physical rehabilitation or medications for headaches, mood, or sleep disturbance may be required. Education, rule changes, and equipment improvements may assist in prevention. The long-term consequences of concussions are not fully understood and merit additional research.

Melatonin as a Therapy for Traumatic Brain Injury: A Review of Published Evidence

Melatonin (MEL) is a hormone that is produced in the brain and is known to bind to MEL-specific receptors on neuronal membranes in several brain regions. MEL’s documented neuroprotective properties, low toxicity, and ability to cross the blood-brain-barrier have led to its evaluation for patients with traumatic brain injury (TBI), a condition for which there are currently no Food and Drug Administration (FDA)-approved therapies. The purpose of this manuscript is to summarize the evidence surrounding the use of melatonin after TBI, as well as identify existing gaps and future directions. To address this aim, a search of the literature was conducted using Pubmed, Google Scholar, and the Cochrane Database. In total, 239 unique articles were screened, and the 22 preclinical studies that met the a priori inclusion/exclusion criteria were summarized, including the study aims, sample (size, groups, species, strain, sex, age/weight), TBI model, therapeutic details (preparation, dose, route, duration), key findings, and conclusions. The evidence from these 22 studies was analyzed to draw comparisons across studies, identify remaining gaps, and suggest future directions. Taken together, the published evidence suggests that MEL has neuroprotective properties via a number of mechanisms with few toxic effects reported. Notably, available evidence is largely based on data from adult male rats and, to a lesser extent, mice. Few studies collected data beyond a few days of the initial injury, necessitating additional longer-term studies. Other future directions include diversification of samples to include female animals, pediatric and geriatric animals, and transgenic strains.

Supplements, nutrition, and alternative therapies for the treatment of traumatic brain injury

Studies using traditional treatment strategies for mild traumatic brain injury (TBI) have produced limited clinical success. Interest in treatment for mild TBI is at an all time high due to its association with the development of chronic traumatic encephalopathy and other neurodegenerative diseases, yet therapeutic options remain limited. Traditional pharmaceutical interventions have failed to transition to the clinic for the treatment of mild TBI. As such, many pre-clinical studies are now implementing non-pharmaceutical therapies for TBI. These studies have demonstrated promise, particularly those that modulate secondary injury cascades activated after injury. Because no TBI therapy has been discovered for mild injury, researchers now look to pharmaceutical supplementation in an attempt to foster success in human clinical trials. Non-traditional therapies, such as acupuncture and even music therapy are being considered to combat the neuropsychiatric symptoms of TBI. In this review, we highlight alternative approaches that have been studied in clinical and pre-clinical studies of TBI, and other related forms of neural injury. The purpose of this review is to stimulate further investigation into novel and innovative approaches that can be used to treat the mechanisms and symptoms of mild TBI.

Sports-Related Concussion: Acute Management and Chronic Postconcussive Issues

Sports-related concussion (SRC) is a common problem in youth sports. Concussion may occur after a forceful hit to the body or head, resulting in transient neuropathological changes that spontaneously resolve with relative rest and activity modification in most patients. Most SRCs are effectively managed by primary care physicians and sports medicine specialists. In some cases, symptoms may persist and the child and adolescent psychiatrist may be consulted. This article reviews important background information regarding SRC and highlights a variety of pharmacologic and nonpharmacologic treatment options that consultant psychiatrists should know.

Sleep Disturbance Following Concussion Is a Risk Factor for a Prolonged Recovery

Sleep disturbance is a common problem following concussion. A retrospective chart review was conducted at a regional concussion clinic on patients 13 to 18 years of age between 2005 and 2011. Statistical analysis evaluated sleep disturbance and duration of concussion, as well as the use and effectiveness of melatonin. A total of 417 patients met inclusion criteria. One hundred twenty-three (34%) reported disturbance in sleep. There was no difference in sleep disturbance based on age, gender, or past number of concussions. Sleep disturbance was associated with a 3- to 4-fold increase in recovery time. Non-sport-related concussions were more likely to be associated with sleep disturbance compared to sport-related concussions (45% vs 29%, P = .01). Melatonin improved sleep disturbance in 67% of the patients. Evaluating sleep disorders following concussion is an important part of the assessment. These findings will help clinicians provide anticipatory guidance and treatment for adolescents recovering from concussion.

Antioxidant therapies in traumatic brain injury: a review

Oxidative stress constitute one of the commonest mechanism of the secondary injury contributing to neuronal death in traumatic brain injury cases. The oxidative stress induced secondary injury blockade may be considered as to be a good alternative to improve the outcome of traumatic brain injury (TBI) treatment. Due to absence of definitive therapy of traumatic brain injury has forced researcher to utilize unconventional therapies and its roles investigated in the improvement of management and outcome in recent year. Antioxidant therapies are proven effective in many preclinical studies and encouraging results and the role of antioxidant mediaction may act as further advancement in the traumatic brain injury management it may represent aonr of newer moadlaity in neurosurgical aramamentorium, this kind of therapy could be a good alternative or adjuct to the previously established neuroprotection agents in TBI.

Manipulating cognitive reserve: Pre-injury environmental conditions influence the severity of concussion symptomology, gene expression, and response to melatonin treatment in rats

In an effort to understand the factors that contribute to heterogeneity in outcomes often associated with mTBI in youth, this study examined the role of premorbid differences in cognitive reserve on post-concussive symptoms (PCS), molecular markers, and treatment response. Male and female rats matured in one of three environmental conditions (Stress, Enrichment, Control), received a mTBI in adolescence, and were randomized to melatonin or placebo treatment. All animals underwent a behavioural test battery designed to examine PCS. Using prefrontal cortex and hippocampus tissue, expression of 9 genes was assessed in an effort to determine how the brain's epigenome was influenced by cognitive reserve, mTBI, and melatonin. Enrichment increased cognitive reserve (CR) and prevented lingering symptoms. Conversely, stress was associated with progressive worsening and manifestation of PCS in the longer-term. Melatonin was able to restore baseline function for control and enriched animals, but was ineffective for the stress condition. Epigenetic change in the prefrontal cortex was largely driven by the injury, while gene expression changes in the hippocampus were dependent upon cognitive reserve. The occurrence and severity of PCS is dependent upon a complex and multifaceted array of factors that modify behavioural and epigenetic responses to mTBI and its treatment.

Pharmacologic Therapies for Pediatric Concussions

Context:

Pediatric concussions are common, and emphasis on correct diagnosis and management is stressed in consensus guidelines. Medications may have a role in management of concussion, but no consensus exists regarding appropriate pharmacologic therapy.

Evidence Acquisition:

Nonsystematic review.

Study Design:

Clinical review.

Level of Evidence:

Level 4.

Results:

There is limited evidence for hypertonic saline to improve posttraumatic headache in the emergency department setting. There is essentially no evidence for the use of any other medication in management of pediatric sport-related concussion.

Conclusion:

Further research is necessary to determine whether there is benefit to the use of any pharmacotherapy in the management of pediatric-aged athletes with concussions.

The Incidence of Postconcussion Syndrome Remains Stable Following Mild Traumatic Brain Injury in Children

BACKGROUND

Improving our knowledge about the natural history and persistence of symptoms following mild traumatic brain injury is a vital step in improving the provision of health care to children with postconcussion syndrome. The purposes of this study were to (1) determine the incidence and persistence of symptoms after mild traumatic brain injury and (2) ascertain whether Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), symptom criteria for postconcussion syndrome in adults are appropriate for use in children.

METHODS

A tertiary care pediatric emergency department was the setting for this study. This was a prospective observational follow-up cohort study of children (ages 2 to 18 years) with mild traumatic brain injury. Data were collected in person during the acute presentation, and subsequent follow-up was performed by telephone at 7-10 days and 1, 2, and 3 months postinjury. Postconcussion Symptom Inventory for parents and children was used. The DSM-IV diagnostic criteria for postconcussion syndrome were explored using receiver operating characteristic curve analysis.

RESULTS

A total of 467 children (62.5% boys, median age 12.04, range 2.34-18.0) with mild traumatic brain injury participated. The median time until symptom resolution was 29.0 days (95% confidence intervals: 26.09-31.91). Three months after injury, 11.8% of children with mild traumatic brain injury remained symptomatic. Receiver operating curve characteristic analysis of the postconcussion syndrome criteria successfully classified symptomatic participants at three months postinjury; the adolescent receiver operating characteristic curve was excellent with the area under the curve being 0.928 (P < 0.001, standard error 0.019).

CONCLUSIONS

Consistent with our previous study, 11.8% of children presenting to the emergency room with a mild traumatic brain injury remain symptomatic at 3 months postinjury. This is the first study to demonstrate stable incidence rates of postconcussion syndrome in children and that modified DSM-IV criteria can be used to successfully classify postconcussion syndrome in children. Although most children report a decay in symptoms over time, 10% of children develop symptoms even though they initially had a good outcome. Caution should be used when using only parent report as a surrogate for childhood outcomes following a concussion.

Measurement of serum melatonin in intensive care unit patients: changes in traumatic brain injury, trauma, and medical conditions

Melatonin is an endogenous hormone mainly produced by the pineal gland whose dysfunction leads to abnormal sleeping patterns. Changes in melatonin have been reported in acute traumatic brain injury (TBI); however, the impact of environmental conditions typical of the intensive care unit (ICU) has not been assessed. The aim of this study was to compare daily melatonin production in three patient populations treated at the ICU to differentiate the role of TBI versus ICU conditions. Forty-five patients were recruited and divided into severe TBI, trauma without TBI, medical conditions without trauma, and compared to healthy volunteers. Serum melatonin levels were measured at four daily intervals at 0400 h, 1000 h, 1600 h, and 2200 h for 7 days post-ICU admission by commercial enzyme linked immunosorbent assay. The geometric mean concentrations (95% confidence intervals) of melatonin in these groups showed no difference being 8.3 (6.3–11.0), 9.3 (7.0–12.3), and 8.9 (6.6–11.9) pg/mL, respectively, in TBI, trauma, and intensive care cohorts. All of these patient groups demonstrated decreased melatonin concentrations when compared to control patients. This study suggests that TBI as well as ICU conditions, may have a role in the dysfunction of melatonin. Monitoring and possibly substituting melatonin acutely in these settings may assist in ameliorating long-term sleep dysfunction in all of these groups, and possibly contribute to reducing secondary brain injury in severe TBI.