Pharmacotherapy for Treatment of Cognitive and Neuropsychiatric Symptoms After mTBI

Inflammasome links traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease

Traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease are three distinct neurological disorders that share common pathophysiological mechanisms involving neuroinflammation. One sequela of neuroinflammation includes the pathologic hyperphosphorylation of tau protein, an endogenous microtubule-associated protein that protects the integrity of neuronal cytoskeletons. Tau hyperphosphorylation results in protein misfolding and subsequent accumulation of tau tangles forming neurotoxic aggregates. These misfolded proteins are characteristic of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease and can lead to downstream neuroinflammatory processes, including assembly and activation of the inflammasome complex. Inflammasomes refer to a family of multimeric protein units that, upon activation, release a cascade of signaling molecules resulting in caspase-induced cell death and inflammation mediated by the release of interleukin-1β cytokine. One specific inflammasome, the NOD-like receptor protein 3, has been proposed to be a key regulator of tau phosphorylation where it has been shown that prolonged NOD-like receptor protein 3 activation acts as a causal factor in pathological tau accumulation and spreading. This review begins by describing the epidemiology and pathophysiology of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease. Next, we highlight neuroinflammation as an overriding theme and discuss the role of the NOD-like receptor protein 3 inflammasome in the formation of tau deposits and how such tauopathic entities spread throughout the brain. We then propose a novel framework linking traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease as inflammasome-dependent pathologies that exist along a temporal continuum. Finally, we discuss potential therapeutic targets that may intercept this pathway and ultimately minimize long-term neurological decline.

Aberrant error monitoring in traumatic brain injuries: A meta-analysis of event-related potential studies

OBJECTIVE

Although individuals with traumatic brain injuries (TBI) often manifest altered error monitoring, evidence using event-related potentials (ERPs) to index these cortical processes is inconsistent. Therefore, this meta-analysis study aimed to comprehensively compare the error-related negativity (ERN) and error positivity (Pe) between individuals with TBI and healthy controls (HC) from the existing literature.

METHODS

Literature search was performed using PubMed/MEDLINE, Web of Science, and Cochrane Library. The effect sizes (Hedges' g) in the comparisons of ERN and Pe amplitudes between TBI and HC groups were employed by a random-effect, inverse-variance weighted model. The effects of age, TBI severity and experimental tasks on both ERP components were also examined.

RESULTS

Random-effect models showed decreased ERN (g = 0.361, p = 0.010), but intact Pe (g = 0.105, p = 0.443), in those with TBI compared to HC. A further analysis revealed that the adult patients (g = 0.326, p = 0.038), but not the youth patients, showed significant reduction of ERN as compared to the HC. However, we did not find moderating effects of TBI severity and experimental paradigms on either ERN or Pe.

CONCLUSIONS

ERN and Pe reflect separate neurophysiological mechanisms and different aspects of error monitoring in TBI. Our findings suggest that attenuated ERN amplitude may be an electrophysiological parameter of error monitoring deficits in TBI.

Cognitive Performance is Associated With 1-Year Participation and Life Satisfaction Outcomes: A Traumatic Brain Injury Model Systems Study

OBJECTIVE

To determine, in persons with traumatic brain injury (TBI), the association between cognitive change after inpatient rehabilitation discharge and 1-year participation and life satisfaction outcomes.

DESIGN

Secondary analysis of prospectively collected TBI Model Systems (TBIMS) data.

SETTING

Inpatient rehabilitation and community.

PARTICIPANTS

499 individuals with TBI requiring inpatient rehabilitation who completed the Brief Test of Adult Cognition by Telephone (BTACT) at inpatient rehabilitation discharge (ie, baseline) and 1-year postinjury.

MAIN OUTCOME MEASURES

Participation Assessment with Recombined Tools-Objective (PART-O) and Satisfaction with Life Scale (SWLS).

RESULTS

Of 2,840 TBIMS participants with baseline BTACT, 499 met inclusion criteria (mean [standard deviation] age = 45 [19] years; 72% male). Change in BTACT executive function (EF) was not associated with 1-year participation (PART-O; β = 0.087, 95% CI [-0.004, 0.178], P = .061) when it was the sole model predictor. Change in BTACT episodic memory (EM) was associated with 1-year participation (β = 0.096, [0.007, 0.184], P = .035), but not after adjusting for demographic, clinical, and functional status covariates (β = 0.067, 95% CI [-0.010, 0.145], P = .089). Change in BTACT EF was not associated with life satisfaction total scores (SWLS) when it was the sole model predictor (β = 0.091, 95% CI [-0.001, 0.182], P = .0503). Change in BTACT EM was associated with 1-year life satisfaction before (β = 0.114, 95% CI [0.025, 0.202], P = .012) and after adjusting for covariates (β = 0.103, [0.014, 0.191], P = .023). In secondary analyses, change in BTACT EF was associated with PART-O Social Relations and Out and About subdomains before (Social Relations: β = 0.127, 95% CI [0.036, 0.217], P = .006; Out and About: β = 0.141, 95% CI [0.051, 0.232], P = .002) and after (Social Relations: β = 0.168, 95% CI [0.072, 0.265], P < .002; Out and About: β = 0.156, 95% CI [0.061, 0.252], P < .002) adjusting for functional status and further adjusting for covariates (Social Relations: β = 0.127, 95% CI [0.040, 0.214], P = .004; Out and About: β = 0.136, 95% CI [0.043, 0.229], P = .004). However, only the models adjusting for functional status remained significant after multiple comparison correction (ie, Bonferroni-adjusted alpha level = 0.002).

CONCLUSION

EF gains during the first year after TBI were related to 1-year social and community participation. Gains in EM were associated with 1-year life satisfaction. These results highlight the potential benefit of cognitive rehabilitation after inpatient rehabilitation discharge and the need for interventions targeting specific cognitive functions that may contribute to participation and life satisfaction after TBI.

Repetitive mild traumatic brain injury impairs norepinephrine system function and psychostimulant responsivity

Traumatic brain injury (TBI) is a complex pathophysiological process that results in a variety of neurotransmitter, behavioral, and cognitive deficits. The locus coeruleus-norepinephrine (LC-NE) system is a critical regulator of arousal levels and higher executive processes affected by TBI including attention, working memory, and decision making. LC-NE axon injury and impaired signaling within the prefrontal cortex (PFC) is a potential contributor to the neuropsychiatric symptoms after single, moderate to severe TBI. The majority of TBIs are mild, yet long-term cognitive deficits and increased susceptibility for further injury can accumulate after each repetitive mild TBI. As a potential treatment for restoring cognitive function and daytime sleepiness after injury psychostimulants, including methylphenidate (MPH) that increase levels of NE within the PFC, are being prescribed "off-label". The impact of mild and repetitive mild TBI on the LC-NE system remains limited. Therefore, we determined the extent of LC-NE and arousal dysfunction and response to therapeutic doses of MPH in rats following experimentally induced single and repetitive mild TBI. Microdialysis measures of basal NE efflux from the medial PFC and arousal measures were significantly lower after repetitive mild TBI. Females showed higher baseline PFC-NE efflux than males following single and repetitive mild TBI. In response to MPH challenge, males exhibited a blunted PFC-NE response and persistent arousal levels following repetitive mild TBI. These results provide critical insight into the role of catecholamine system dysfunction associated with cognitive deficits following repeated injury, outcome differences between sex/gender, and lack of success of MPH as an adjunctive therapy to improve cognitive function following injury.

Investigation of Mild Traumatic Brain Injury Home Cage Behavior: The Home Cage Assay Advantages

This study utilized the Noldus PhenoTyper Home Cage Monitoring system (HCM) to assess the behavioral and cognitive changes of experimental closed-head mild traumatic brain injury (mTBI). Seventy-nine adult male Institute of Cancer Research (ICR) mice were subjected to either a sham procedure or closed-head mTBI using the weight-drop model. Seven days post-injury, separate cohorts of mice underwent either a non-cognitive or a cognitive home cage assessment, a treadmill fatigue test, or the Open Field Test. mTBI significantly influenced habituation behavior and circadian wheel-running activity. Notably, mTBI mice exhibited an increased frequency of visits to the running wheel, but each visit was shorter than those of controls. No significant differences between the groups in discrimination or reversal learning performance were observed. However, during the reversal learning stage, mTBI mice performed similarly to their initial discrimination learning levels, suggesting an abnormally faster rate of reversal learning. Home cage monitoring is a valuable tool for studying the subtle effects of mTBI, complementing traditional assays. The automated evaluation of habituation to novel stimuli (e.g., novel environment) could serve as a potentially sensitive tool for assessing mTBI-associated behavioral deficits.

Combined Use of Guanfacine and N-Acetylcysteine for the Treatment of Cognitive Deficits After Traumatic Brain Injury

Traumatic Brain Injury (TBI) is a significant contributor to disability across the world. TBIs vary in severity, and most cases are designated mild TBI (mTBI), involving only brief loss of consciousness and no intracranial findings on imaging. Despite this categorization, many persons continue to report persistent cognitive changes in the months to years after injury, with particular impairment in the cognitive and executive functions of the pre-frontal cortex. For these persons, there are no currently approved medications, and treatment is limited to symptom management and cognitive or behavioral therapy. The current case studies explored the use of the alpha-2A adrenoreceptor agonist, guanfacine, combined with the antioxidant, N-acetylcysteine (NAC), in the treatment of post-TBI cognitive symptoms, based on guanfacine's ability to strengthen pre-frontal cortical function, and the open-label use of NAC in treating TBI. Two persons from our TBI clinic were treated with this combined regimen, with neuropsychological testing performed pre- and post-treatment. Guanfacine + NAC improved attention, processing speed, memory, and executive functioning with minimal side effects in both persons. These results encourage future placebo-controlled trials to more firmly establish the efficacy of guanfacine and NAC for the treatment of cognitive deficits caused by TBI.

The effect of amantadine on acute cognitive disability after severe traumatic brain injury: An institutional pilot study

BACKGROUND

Amantadine is used in the post-acute care setting to improve cognitive function after a traumatic brain injury. Its utility in the acute postinjury period is unknown. In this pilot study, we sought to examine the effect of amantadine on short-term cognitive disability among patients with a severe traumatic brain injury and hypothesized that patients receiving amantadine would have a greater improvement in disability throughout their acute hospitalization.

METHODS

We performed a prospective, observational study of patients ≥18 years with severe traumatic brain injury (Glasgow Coma Scale ≤8) at a level I trauma center between 2020 and 2022. Patients with penetrating trauma, death within 48 hours of admission, and no radiographic evidence of intracranial pathology were excluded. Patients were grouped according to whether they received amantadine. Our primary outcome was the change in cognitive disability, measured by the Disability Rating Scale (DRS), over the index hospitalization.

RESULTS

There were 55 patients in the cohort: 41.8% (n = 23) received amantadine and 58.2% (n = 32) did not. There were higher rates of motor vehicle collisions (65.2% vs 46.9%, P = .02), diffuse axonal injury (47.8% vs 18.8%, P = .02), intracranial pressure monitor use (73.9% vs 21.9%, P = .0001), and propranolol use (73.9% vs 21.9%, P = .0001) in the amantadine. There was a larger improvement in DRS scores among patients receiving amantadine (7.8 vs 3.6, P = .001), and amantadine independently predicted improvement in DRS scores (β, 1.61; 95% confidence interval, 0.20-3.02, P = .03). Rates of discharge to traumatic brain injury rehabilitation were significantly higher in the amantadine group (73.9% vs 21.9%, P = .0002).

CONCLUSION

Among patients with severe traumatic brain injury, amantadine use in the acute postinjury period may be associated with an improvement in cognitive disability and discharge to traumatic brain injury rehabilitation.

Methylphenidate for neurological improvement post-TBI

Traumatic brain injuries (TBIs) can have numerous neurologic and cognitive sequelae. The road to recovery can be long and arduous for many patients. Improving cognition can assist in a shorter recovery time as patients may be more in tune with their plan of care. Family physicians may be helpful in assisting with the recovery process post-hospital discharge. This case report seeks to educate family physicians on the use of methylphenidate in the ambulatory setting after TBI. Here, a case of a 51-year-old man on methylphenidate after a traumatic brain injury is presented.

Serotonin Syndrome Precipitated by Amantadine in a Patient With Persistent Post Concussive Symptoms - A Case Report

Symptoms after mild traumatic brain injury (MTBI) can persist for greater than 1 month in up to 20% of individuals, yet there are no current medications approved by the Food and Drug Administration for treatment of specific concussion related sequelae. Amantadine, a dopamine agonist and N-Methyl-D-aspartate antagonist, is increasingly being used as a treatment option for individuals with traumatic brain injury across the spectrum of injury severity. This case report describes a 22-year-old individual who sustained an MTBI without loss of consciousness or post-traumatic amnesia after striking their head against a metal cabinet. The individual was referred to an interdisciplinary outpatient brain rehabilitation program secondary to persistent symptoms after MTBI, was prescribed amantadine for post-traumatic headache 97 days after injury, and subsequently developed symptoms of serotonin syndrome (SS) within 10 days of medication initiation. While SS caused by amantadine has been described in individuals with renal failure, this case report is the first to describe amantadine precipitating SS - confirmed by a validated diagnostic criterion and successfully treated with lorazepam and cyproheptadine - in a patient with normal renal function already on duloxetine, bupropion, and gabapentin. This case report is important in elucidating potential contributions of amantadine to the development of SS and highlighting the important role clinicians have in assessing for polypharmacy when prescribing amantadine for individuals with traumatic and acquired brain injuries.

Loss of Consciousness and Righting Reflex Following Traumatic Brain Injury: Predictors of Post-Injury Symptom Development (A Narrative Review)

Identifying predictors for individuals vulnerable to the adverse effects of traumatic brain injury (TBI) remains an ongoing research pursuit. This is especially important for patients with mild TBI (mTBI), whose condition is often overlooked. TBI severity in humans is determined by several criteria, including the duration of loss of consciousness (LOC): LOC < 30 min for mTBI and LOC > 30 min for moderate-to-severe TBI. However, in experimental TBI models, there is no standard guideline for assessing the severity of TBI. One commonly used metric is the loss of righting reflex (LRR), a rodent analogue of LOC. However, LRR is highly variable across studies and rodents, making strict numeric cutoffs difficult to define. Instead, LRR may best be used as predictor of symptom development and severity. This review summarizes the current knowledge on the associations between LOC and outcomes after mTBI in humans and between LRR and outcomes after experimental TBI in rodents. In clinical literature, LOC following mTBI is associated with various adverse outcome measures, such as cognitive and memory deficits; psychiatric disorders; physical symptoms; and brain abnormalities associated with the aforementioned impairments. In preclinical studies, longer LRR following TBI is associated with greater motor and sensorimotor impairments; cognitive and memory impairments; peripheral and neuropathology; and physiologic abnormalities. Because of the similarities in associations, LRR in experimental TBI models may serve as a useful proxy for LOC to contribute to the ongoing development of evidence-based personalized treatment strategies for patients sustaining head trauma. Analysis of highly symptomatic rodents may shed light on the biological underpinnings of symptom development after rodent TBI, which may translate to therapeutic targets for mTBI in humans.

Concussion and Psychological Effects: A Review of Recent Literature

ABSTRACT

The aim of this article is to provide an up-to-date review of psychological changes in association with postconcussive athletes. In particular, this article focused on the symptomatology, risk factors, and treatment of psychiatric diagnoses in patients who suffered a sports-related concussion (SRC). After an extensive review of prior and current literature, there is significant evidence that demonstrates an association of changes in mood and behavior, including new or worsening symptoms of anxiety, depression, and difficulty with attention and concentration in those who are recovering from a concussion. The goal of care in these patients is to identify and treat these psychological symptoms early to have more favorable long-term outcomes. Primary treatment should focus on psychotherapy; however, other considerations may be warranted in certain cases, such as selective serotonin reuptake inhibitors for depression and tricyclic antidepressants and gabapentin for short-term cognitive symptom improvement.

Posttraumatic Stress and Traumatic Brain Injury: Cognition, Behavior, and Neuroimaging Markers in Vietnam Veterans

BACKGROUND

Posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) are common in Veterans and linked to behavioral disturbances, increased risk of cognitive decline, and Alzheimer's disease.

OBJECTIVE

We studied the synergistic effects of PTSD and TBI on behavioral, cognitive, and neuroimaging measures in Vietnam war Veterans.

METHODS

Data were acquired at baseline and after about one-year from male Veterans categorized into: PTSD, TBI, PTSD+TBI, and Veteran controls without PTSD or TBI. We applied manual tractography to examine white matter microstructure of three fiber tracts: uncinate fasciculus (N = 91), cingulum (N = 87), and inferior longitudinal fasciculus (N = 95). ANCOVAs were used to compare Veterans' baseline behavioral and cognitive functioning (N = 285), white matter microstructure, amyloid-β (N = 230), and tau PET (N = 120). Additional ANCOVAs examined scores' differences from baseline to follow-up.

RESULTS

Veterans with PTSD and PTSD+TBI, but not Veterans with TBI only, exhibited poorer behavioral and cognitive functioning at baseline than controls. The groups did not differ in baseline white matter, amyloid-β, or tau, nor in behavioral and cognitive functioning, and tau accumulation change. Progression of white matter abnormalities of the uncinate fasciculus in Veterans with PTSD compared to controls was observed; analyses in TBI and PTSD+TBI were not run due to insufficient sample size.

CONCLUSIONS

PTSD and PTSD+TBI negatively affect behavioral and cognitive functioning, while TBI does not contribute independently. Whether progressive decline in uncinate fasciculus microstructure in Veterans with PTSD might account for cognitive decline should be further studied. Findings did not support an association between PTSD, TBI, and Alzheimer's disease pathology based on amyloid and tau PET.

Human embryonic stem cell-derived cerebral organoids for treatment of mild traumatic brain injury in a mouse model

OBJECTIVE

There are no effective treatments for relieving neuronal dysfunction after mild traumatic brain injury (TBI). Here, we evaluated therapeutic efficacy of human embryonic stem cell-derived cerebral organoids (hCOs) in a mild TBI model, in terms of repair of damaged cortical regions, neurogenesis, and improved cognitive function.

METHODS

Male C57BL/6 J mice were randomly divided into sham-operated, mild TBI, and mild TBI with hCO groups. hCOs cultured at 8 weeks were used for transplantation. Mice were sacrificed at 7 and 14 days after transplantation followed by immunofluorescence staining, cytokine profile microarray, and novel object recognition test.

RESULTS

8W-hCOs transplantation significantly reduced neuronal cell death, recovered microvessel density, and promoted neurogenesis in the ipsilateral subventricular zone and dentate gyrus of hippocampus after mild TBI. In addition, increased angiogenesis into the engrafted hCOs was observed. Microarray results of hCOs revealed neuronal differentiation potential and higher expression of early brain development proteins associated with neurogenesis, angiogenesis and extracellular matrix remodeling. Ultimately, 8W-hCO transplantation resulted in reconstruction of damaged cortex and improvement in cognitive function after mild TBI.

CONCLUSION

hCO transplantation may be feasible for treating mild TBI-related neuronal dysfunction via reconstruction of damaged cortex and neurogenesis in the hippocampus.

Donepezil Beyond Alzheimer's Disease? A Narrative Review of Therapeutic Potentials of Donepezil in Different Diseases

Donepezil hydrochloride is an acetylcholine esterase inhibitor studied and approved to treat Alzheimer's disease (AD). However, this drug can have positive therapeutic potential in treating different conditions, including various neurodegenerative disorders such as other types of dementia, multiple sclerosis, Parkinson's disease, psychiatric and mood disorders, and even infectious diseases. Hence, this study reviewed the therapeutic potential of this drug in treating Alzheimer's and other diseases by reviewing the articles from databases including Web of Science, Scopus, PubMed, Cochrane, and Science Direct. It was shown that donepezil could affect the pathophysiology of these diseases via mechanisms such as increasing the concentration of acetylcholine, modulating local and systemic inflammatory processes, affecting acetylcholine receptors like nicotinic and muscarinic receptors, and activating various cellular signaling via receptors like sigma-1 receptors. Despite many therapeutic potentials, this drug has not yet been approved for treating non-Alzheimer's diseases, and more comprehensive studies are needed.

The University of Kansas Health System Outpatient Clinical Concussion Comprehensive Protocol: An Interdisciplinary Approach

Objective:

The concussion team at The University of Kansas Health System outpatient rehabilitation spine center is comprised of experienced multi-disciplinary experts including physical therapists and a speech language pathologist. The team set forth with a purpose of creating and organizing an internal physical therapy clinical recommendation protocol for initial evaluations and subsequent treatments for the concussed patient. The aim of this paper is to share these recommendation protocols with other therapy teams and provide a foundational layout for treating the patient with post-concussion symptoms in an outpatient physical therapy clinical setting.

Study design:

Clinical recommendation protocol provides guidance for patients ages 10+ from initial evaluation through discharge with emphasis on evidence-based research in the areas of: oculomotor, cervical, vestibular, post-concussion migraine influence, mood disorders(such as anxiety and depression), exertion, and cognitive communicative dysfunction.

Results:

Finding a written, comprehensive clinical resource protocol for post-concussion outpatient evaluation(s) and treatment strategies can be difficult. This document serves as a resource for other outpatient concussion rehabilitation clinics, providing rationale, and objective measurement tools, for assessing and treating concussion patients. To the authors’ knowledge, no other research has produced a practical, efficient evaluation tool to be utilized at bed side, condensing evidence-based research into an easy-to-use form.

Conclusion:

The University of Kansas Health System outpatient concussion rehabilitation center developed clinical recommendation protocols for concussion care. The intent was to standardize assessment and treatment for concussion patients and to share these objective measurement tools and procedures, focused on a team approach of concussion providers, as a clinical outline for both the novice and seasoned clinician specializing in the field of concussion work in an outpatient rehabilitation setting.

Treatment and Rehabilitation for Traumatic Brain Injury: Current Update

Traumatic brain injury (TBI) is an acquired injury to the brain caused by external mechanical forces, which can cause temporary or permanent disability. TBI and its potential long-term consequences are serious public health concerns. This review seeks to provide updated information on the current methods of management of patients with TBI to improve patient care.

Pharmacotherapy for mild traumatic brain injury: an overview of the current treatment options

INTRODUCTION

Accounting for 90% of all traumatic brain injuries (TBIs), mild traumatic brain injury (mTBI) is currently the most frequently seen type of TBI. Although most patients can recover from mTBI, some may suffer from prolonged symptoms for months to years after injury. Growing evidence indicates that mTBI is associated with neurodegenerative diseases including dementias and Parkinson's disease (PD). Pharmacological interventions are necessary to address the symptoms and avoid the adverse consequences of mTBI.

AREAS COVERED

To provide an overview of the current treatment options, the authors herein review the potential drugs to reduce the secondary damage and symptom-targeted therapy as well as the ongoing clinical trials about pharmacotherapy for mTBI.

EXPERT OPINION

There has been no consensus on the pharmacotherapy for mTBI. Several candidates including n-3 PUFAs, melatonin, NAC and statins show potential benefits in lessening the secondary injury and improving neurological deficits in pre-clinic studies, which, however, still need further investigation in clinical trials. The current pharmacotherapy for mTBI is empirical in nature and mainly targets to mitigate the symptoms. Well-designed clinical trials are now warranted to provide high level evidence.

Neuropsychological and neuropsychiatric recovery from mild traumatic brain injury

PURPOSE OF REVIEW

Mild traumatic brain injury (mTBI) is a significant public health concern for children. This review summarizes recent literature on early symptoms and neuropsychiatric and neuropsychological outcomes following pediatric mTBI and highlights factors that predict prolonged recovery. Evidence-based recommendations for assessment and treatment are also discussed.

RECENT FINDINGS

Whereas most children recover within 1 month after mTBI, 10-30% of children experience lingering neuropsychiatric or neuropsychological symptoms 3 months or more after injury. For the subset who experience prolonged recovery, new or worsening emotional and behavioral symptoms are the most frequent concerns. Recent research has suggested that specific factors, including preinjury mental health concerns, female sex, and family characteristics, are associated with increased risk of experiencing prolonged recovery. Early management includes reassurance, brief rest (1-3 days), and gradual return to typical activities. When symptoms linger for more than 4 weeks, evaluation in a specialty clinic is recommended and multimodal therapies are considered. Active recovery models, which include gradual return to aerobic exercise and cognitive behavioral approaches, are promising for the management of prolonged symptoms.

SUMMARY

A minority of children with mTBI experience prolonged neuropsychiatric or neuropsychological concerns. While our understanding of pediatric mTBI is growing, and recommendations for assessment and management have been developed, many gaps remain.

Randomized trial of rTMS in traumatic brain injury: improved subjective neurobehavioral symptoms and increases in EEG delta activity

PRIMARY OBJECTIVE

While repetitive transcranial magnetic stimulation (rTMS) has shown efficacy for cognitive difficulties accompanying depression, it is unknown if it can improve cognition in persons with traumatic brain injury.

RESEARCH DESIGN

Using a sham-controlled crossover design, we tested the capacity of high frequency rTMS of the prefrontal cortex to improve neuropsychological performance in attention, learning and memory, and executive function.

METHODS

Twenty-six participants with cognitive complaints and a history of mild-to-moderate traumatic brain injury were randomly assigned to receive first either active or sham 10 Hz stimulation for 20 minutes (1200 pulses) per session for five consecutive days. After a one-week washout, the other condition (active or sham) was applied. Pre- and post-treatment measures included neuropsychological tests, cognitive and emotional symptoms, and EEG.

MAIN OUTCOMES AND RESULTS

Results indicated no effect of treatment on cognitive function. Subjective measures of depression, sleep dysfunction, post-concussive symptoms (PCS), and executive function showed significant improvement with stimulation, retaining improved levels at two-week follow-up. EEG delta power exhibited elevation one week after stimulation cessation.

CONCLUSIONS

While there is no indication that rTMS is beneficial for neuropsychological performance, it may improve PCS and subjective cognitive dysfunction. Long-term alterations in cortical oscillations may underlie the therapeutic effects of rTMS.

Effect of acupuncture treatment on cognitive impairment after traumatic brain injury in adults: A protocol for systematic review

BACKGROUND

Acupuncture has been widely used to treat cognitive impairment after traumatic brain injury (TBI). But its efficiency has not been scientifically and methodically evaluated. The objective of this study is to evaluate the efficiency and safety of the acupuncture treatment for cognitive impairment after TBI in adults.

METHODS

This protocol of systematic review will be conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols. We will conduct the literature searching in the following electronic databases: the Cochrane Library, MEDLINE, EMBASE, Web of Science, Springer, the Chinese Science Citation Database (CSCD), China National Knowledge Infrastructure (CNKI), the Chinese Biomedical Literature Database (CBM), Wanfang, and the Chinese Scientific Journal Database (VIP). The time limit for retrieving studies is from establishment to November 2021 for each database. All published randomized controlled trials related to this review will be included. Review Manager (V.5.3.5) will be implemented for the assessment of bias risk and data analyses. The selection of the studies, data abstraction, and validations will be performed independently by 2 researchers.

RESULTS

This review will assess the clinical efficacy and safety, as well as the acupoints characteristics of acupuncture on CI of TBI in adults.

CONCLUSION

This review will summarize the current evidence of acupuncture on CI of TBI outcomes and provide guidance for clinicians and patients to select acupuncture for CI of TBI in adults.

TRAIL REGISTRATION NUMBER

This protocol of systematic review has been registered on INPLASY website (No. INPLASY2021110113).

Number of traumatic brain injuries and temporal associations with depression: A register-based cohort study

OBJECTIVE

To explore the association of the number of traumatic brain injuries (TBIs) and temporal associations with the subsequent risk of depression in the population.

METHODS

National register-based cohort study on all individuals registered with TBI (ICD-10: S06, ICD-8: 85.0-85.5) from 1977 to 2015 in Denmark (n = 494,216) and a sex- and age-matched reference population (n = 499,505). The associations with the number of TBIs and time to depression (0-6, 7-12 and more than 12 months following TBI) were analyzed using Cox proportional hazard regression.

RESULTS

During a follow-up of mean 14.5 (SD 11.3) years, a total of 27,873 (5.6%) individuals who had at least one TBI and 15,195 (3.0%) in the reference population were diagnosed with a depression. First-time TBI was associated with a higher risk of depression in both men (HR = 1.73 [95% CI:1.67-1.79]) and women (HR = 1.66 [95% CI:1.61-1.70]) after multiple adjustments for educational status and comorbidities including previous depression, and the association became stronger in a dose-response association with the number of TBIs (test for trend p < 0.01). The HRs for depression were highest the first 6 months after the TBI in both men (HR = 5.69 [95% CI:4.66-6.94]) and women (HR = 4.55 [95% CI:3.93-5.26]) and decreased gradually the following year but remained elevated from one year after TBI until end of follow-up independent of the number of TBIs (p < 0.01). The associations did not vary with age or calendar time.

CONCLUSION

Traumatic brain injury is associated with a higher risk of depression, especially in the first months after TBI and the risk increases with the number of TBIs.

Dual Neurostimulant Therapy May Optimize Acute Neurorecovery for Severe Traumatic Brain Injuries

BACKGROUND

Neurostimulants (NS) can be used to treat patients with a traumatic brain injury (TBI) with altered levels of consciousness. We sought to determine if amantadine alone (monotherapy) versus amantadine + methylphenidate (dual therapy) would correlate with better neurorecovery (NR) among acutely hospitalized patients with a severe TBI.

METHODS

We performed a retrospective review of adult patients admitted to our level I trauma center from 2016-2019 with a severe TBI. NR was calculated by dividing the difference between admission and discharge Glasgow Coma Scale (GCS) scores by 12. Resulting ratios were used to divide the cohort into two groups: excellent NR (1) and non-excellent NR (<1).

RESULTS

A total of 76 patients comprised the cohort; 19.7% (n = 15) had excellent NR. The excellent NR group had a larger proportion of patients receiving dual therapy compared to the non-excellent group (86.7% versus 59%, P = 0.04). In monotherapy (n = 27), amantadine was initiated 13 (8-20) d following injury and treatment lasted 7 (2-16) d. In dual therapy (n = 49), amantadine was initiated 12 (6-19) d following injury and continued for 9 (4-25.5) d. Methylphenidate was initiated 15 (7-20.5) d following injury and continued for 5 (2-13.5) d. After adjusting for confounders, dual versus monotherapy predicted excellent NR (OR 5.4, 95% CI 1.2 - 38.9, P = 0.03).

CONCLUSIONS

During the acute hospitalization for a severe TBI, dual NS therapy compared to monotherapy is associated with an increased likelihood of excellent NR. Larger prospective trials are warranted to validate these findings.