Fatigue after traumatic brain injury: Association with neuroendocrine, sleep, depression and other factors

Dynamic Prevalence of and Factors Associated With Fatigue Following Traumatic Brain Injury: A Systematic Review and Meta-analysis of Observational Studies

OBJECTIVE

To implement a systematic review and meta-analysis to comprehensively synthesize the prevalence of and factors associated with fatigue following traumatic brain injury (TBI).

METHODS

We systematically searched the PubMed, EMBASE, Cochrane Library, Cumulated Index to Nursing and Allied Health Literature, PsycINFO, and ProQuest Dissertations and Theses A&I databases in all fields from their inception to March 31, 2021. We included observational studies investigating fatigue at specific time points following TBI or factors associated with post-TBI fatigue. All data were analyzed using a random-effects model.

RESULTS

This meta-analysis included 29 studies that involved 12 662 patients with TBI and estimated the prevalence of post-TBI fatigue (mean age = 41.09 years); the meta-analysis also included 23 studies that involved 6681 patients (mean age = 39.95 years) and investigated factors associated with post-TBI fatigue. In patients with mild-to-severe TBI, the fatigue prevalence rates at 2 weeks or less, 1 to 3 months, 6 months, 1 year, and 2 years or more after TBI were 52.2%, 34.6%, 36.0%, 36.1%, and 48.8%, respectively. Depression ( r = 0.48), anxiety ( r = 0.49), sleep disturbance ( r = 0.57), and pain ( r = 0.46) were significantly associated with post-TBI fatigue. No publication bias was identified among the studies, except for those assessing fatigue prevalence at 6 months after TBI.

CONCLUSION

The pooled prevalence rates of post-TBI fatigue exhibited a U-shaped pattern, with the lowest prevalence rates occurring at 1 to 3 months after TBI. Depression, anxiety, sleep disturbance, and pain were associated with post-TBI fatigue. Younger patients and male patients were more likely to experience post-TBI fatigue. Our findings can assist healthcare providers with identifying appropriate and effective interventions targeting post-TBI fatigue at specific periods.

Methylphenidate Ameliorates Behavioural and Neurobiological Deficits in Executive Function for Patients with Chronic Traumatic Brain Injury

(1) Background: Traumatic brain injury (TBI) often results in cognitive impairments, including in visuospatial planning and executive function. Methylphenidate (MPh) demonstrates potential improvements in several cognitive domains in patients with TBI. The Tower of London (TOL) is a visuospatial planning task used to assess executive function. (2) Methods: Volunteers with a history of TBI (n = 16) participated in a randomised, double-blinded, placebo-controlled, fMRI study to investigate the neurobiological correlates of visuospatial planning and executive function, on and off MPh. (3) Results: Healthy controls (HCs) (n = 18) and patients on placebo (TBI-placebo) differed significantly in reaction time (p < 0.0005) and accuracy (p < 0.0001) when considering all task loads, but especially for high cognitive loads for reaction time (p < 0.001) and accuracy (p < 0.005). Across all task loads, TBI-MPh were more accurate than TBI-placebo (p < 0.05) but remained less accurate than HCs (p < 0.005). TBI-placebo substantially improved in accuracy with MPh administration (TBI-MPh) to a level statistically comparable to HCs at low (p = 0.443) and high (p = 0.175) cognitive loads. Further, individual patients that performed slower on placebo at low cognitive loads were faster with MPh (p < 0.05), while individual patients that performed less accurately on placebo were more accurate with MPh at both high and low cognitive loads (p < 0.005). TBI-placebo showed reduced activity in the bilateral inferior frontal gyri (IFG) and insulae versus HCs. MPh normalised these regional differences. MPh enhanced within-network connectivity (between parietal, striatal, insula, and cerebellar regions) and enhanced beyond-network connectivity (between parietal, thalamic, and cerebellar regions). Finally, individual changes in cerebellar-thalamic (p < 0.005) and cerebellar-parietal (p < 0.05) connectivity with MPh related to individual changes in accuracy with MPh. (4) Conclusions: This work highlights behavioural and neurofunctional differences between HCs and patients with chronic TBI, and that adverse differences may benefit from MPh treatment.

Fatigue in young patients with acquired brain injury in the outpatient rehabilitation setting: A 2-year follow-up study

Acquired brain injury (ABI) may cause fatigue and participation restrictions in young patients. However, knowledge regarding the course of these problems over time is lacking. This study aims to describe the course of fatigue and participation and their relationship over time in an observational two-year follow-up study among patients(5-24 years) with ABI referred for outpatient rehabilitation and their parents. Patients/parents completed the PedsQL™Multidimensional-Fatigue-Scale(PedsQL™MFS, totalscore/3-domains) and the Child/Adolescent-Scale of Participation(CASP, totalscore/4-domains). Scores ranged from 0-100: lower scores = more fatigue/participation problems. Linear mixed models and repeated measures correlations were used to determine the course over time (change-scores/95%CI) and correlations between fatigue/participation. At baseline, 223 patients/246 parents participated with 94/104 at either T1, T2 or both. Median age was 15 years (IQR:12-17), 74% had a traumatic brain injury. Mean(SD) patient/parent-reported PedsQL™MFS totalscores(baseline) were: 50.3(17.3) and 53.8(19.1), respectively. CASP totalscores were 78.0(16.4) and 87.1(13.6). Over time, patient-reported scores improved significantly (fatigue: + 8.8 (2.9;14.7), p < 0.05)/participation: + 10.5 (6.3;14.7), p < 0.05)). Similar results were found regarding parent-reported fatigue: + 8.7 (3.4;13.9), p < 0.05 but not regarding participation. Two years later, fatigue was still considerable(patients:59.1/parents:62.5). Moderate/fair correlations between fatigue/participation over time were found. Fatigue and participation in young patients with ABI improved two years after referral to rehabilitation. However, fatigue remained a considerable problem.

Fatigue recovery and connected factors following paediatric concussion

OBJECTIVE

Using a biopsychosocial framework and the three-factor fatigue model, we aimed to (1) plot recovery of fatigue over the 3 months following paediatric concussion and (2) explore factors associated with persisting fatigue during the first 3 months postconcussion.

METHODS

240 children and adolescents aged 5-18 years (M=11.64, SD=3.16) completed assessments from time of injury to 3 months postinjury. Separate linear mixed effects models were conducted for child and parent ratings on the PedsQL-Multidimensional Fatigue Scale to plot recovery across domains (General, Cognitive, Sleep/Rest) and Total fatigue, from 1 week to 3 months postinjury. Two-block hierarchical regression analyses were then conducted for parent and child ratings of fatigue at each time point, with age, sex and acute symptoms in block 1 and child and parent mental health variables added to block 2.

RESULTS

There was a significant reduction in both child and parent ratings across the 3 months postinjury for all fatigue domains (all p<0.001). For both child and parent fatigue ratings, child mental health was the most significant factor associated with fatigue at all time points. Adding child and parent mental health variables in the second block of the regression substantially increased the variance explained for both child and parent ratings of fatigue.

CONCLUSION

Our findings confirm that fatigue improves during the first 3 months postconcussion and highlights the importance of considering child and parent mental health screening when assessing patients with persisting postconcussive symptoms.

Understanding the Relationships Between Sleep Quality and Depression and Anxiety in Neurotrauma: A Scoping Review

Sleep problems, depression, and anxiety are highly prevalent after a spinal cord injury (SCI) and traumatic brain injury (TBI) and may worsen functional outcomes and quality of life. This scoping review examined the existing literature to understand the relationships between sleep quality, depression, and anxiety in persons with SCI and TBI, and to identify gaps in the literature. A systematic search of seven databases was conducted. The findings of 30 eligible studies reporting associations between sleep quality and depression and/or anxiety after SCI or TBI were synthesized. The included studies were mostly cross-sectional and employed a range of subjective and objective measures of sleep quality. Poor subjective sleep quality and insomnia tended to be significantly associated with increased levels of depression and/or anxiety, but no such associations were reported when sleep quality was measured objectively. Two longitudinal studies observed worsening depressive symptoms over time were related to insomnia and persistent sleep complaints. Two interventional studies found that treating sleep problems improved symptoms of depression and anxiety. The findings of this review suggest that sleep and psychopathology are related in persons with neurotraumatic injuries. This has important therapeutic implications, because individuals may benefit from therapy targeting both sleep and psychological issues. More longitudinal and interventional studies are warranted to further understand the direction and strength of the relationships and how they impact patient outcomes.

Characterizing the profiles of patients with acute concussion versus prolonged post-concussion symptoms in Ontario

Identifying vulnerability factors for developing persisting concussion symptoms is imperative for determining which patients may require specialized treatment. Using cross-sectional questionnaire data from an Ontario-wide observational concussion study, we compared patients with acute concussion (≤ 14 days) and prolonged post-concussion symptoms (PPCS) (≥ 90 days) on four factors of interest: sex, history of mental health disorders, history of headaches/migraines, and past concussions. Differences in profile between the two groups were also explored. 110 patients with acute concussion and 96 patients with PPCS were included in our study. The groups did not differ on the four factors of interest. Interestingly, both groups had greater proportions of females (acute concussion: 61.1% F; PPCS: 66.3% F). Patient profiles, however, differed wherein patients with PPCS were significantly older, more symptomatic, more likely to have been injured in a transportation-related incident, and more likely to live outside a Metropolitan city. These novel risk factors for persisting concussion symptoms require replication and highlight the need to re-evaluate previously identified risk factors as more and more concussions occur in non-athletes and different risk factors may be at play.

Mild Traumatic Brain Injury Affects Orexin/Hypocretin Physiology Differently in Male and Female Mice

Traumatic brain injury (TBI) is known to affect the physiology of neural circuits in several brain regions, which can contribute to behavioral changes after injury. Disordered sleep is a behavior that is often seen after TBI, but there is little research into how injury affects the circuitry that contributes to disrupted sleep regulation. Orexin/hypocretin neurons (hereafter referred to as orexin neurons) located in the lateral hypothalamus normally stabilize wakefulness in healthy animals and have been suggested as a source of dysregulated sleep behavior. Despite this, few studies have examined how TBI affects orexin neuron circuitry. Further, almost no animal studies of orexin neurons after TBI have included female animals. Here, we address these gaps by studying changes to orexin physiology using ex vivo acute brain slices and whole-cell patch clamp recording. We hypothesized that orexin neurons would have reduced afferent excitatory activity after injury. Ultimately, this hypothesis was supported but there were additional physiological changes that occurred that we did not originally hypothesize. We studied physiological properties in orexin neurons approximately 1 week after mild traumatic brain injury (mTBI) in 6-8-week-old male and female mice. mTBI was performed with a lateral fluid percussion injury between 1.4 and 1.6 atmospheres. Mild TBI increased the size of action potential afterhyperpolarization in orexin neurons from female mice, but not male mice and reduced the action potential threshold in male mice, but not in female mice. Mild TBI reduced afferent excitatory activity and increased afferent inhibitory activity onto orexin neurons. Alterations in afferent excitatory activity occurred in different parameters in male and female animals. The increased afferent inhibitory activity after injury is more pronounced in recordings from female animals. Our results indicate that mTBI changes the physiology of orexin neuron circuitry and that these changes are not the same in male and female animals.

Evaluating the state of non-invasive imaging biomarkers for traumatic brain injury

Non-invasive imaging biomarkers are useful for prognostication in patients with traumatic brain injury (TBI) at high risk for morbidity with invasive procedures. The authors present findings from a scoping review discussing the pertinent biomarkers. Embase, Ovid-MEDLINE, and Scopus were queried for original research on imaging biomarkers for prognostication of TBI in adult patients. Two reviewers independently screened articles, extracted data, and evaluated risk of bias. Data was synthesized and confidence evaluated with the linked evidence according to the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. Our search yielded 3104 unique citations, 44 of which were included in this review. Study populations varied in TBI severity, as defined by Glasgow Coma Scale (GCS), including: mild (n=9), mild and moderate (n=3), moderate and severe (n=7), severe (n=6), and all GCS scores (n=17). Diverse imaging modalities were used for prognostication, predominantly computed tomography (CT) only (n=11), magnetic resonance imaging (MRI) only (n=9), and diffusion tensor imaging (DTI) (N=9). The biomarkers included diffusion coefficient mapping, metabolic characteristics, optic nerve sheath diameter, T1-weighted signal changes, cortical cerebral blood flow, axial versus extra-axial lesions, T2-weighted gradient versus spin echo, translocator protein levels, and trauma imaging of brainstem areas. The majority (93%) of studies identified that the imaging biomarker of interest had a statistically significant prognostic value; however, these are based on a very low to low level of quality of evidence. No study directly compared the effects on specific TBI treatments on the temporal course of imaging biomarkers. The current literature is insufficient to make a strong recommendation about a preferred imaging biomarker for TBI, especially considering GRADE criteria revealing low quality of evidence. Rigorous prospective research of imaging biomarkers of TBI is warranted to improve the understanding of TBI severity.

Traumatic brain injury: Mechanisms, manifestations, and visual sequelae

Traumatic brain injury (TBI) results when external physical forces impact the head with sufficient intensity to cause damage to the brain. TBI can be mild, moderate, or severe and may have long-term consequences including visual difficulties, cognitive deficits, headache, pain, sleep disturbances, and post-traumatic epilepsy. Disruption of the normal functioning of the brain leads to a cascade of effects with molecular and anatomical changes, persistent neuronal hyperexcitation, neuroinflammation, and neuronal loss. Destructive processes that occur at the cellular and molecular level lead to inflammation, oxidative stress, calcium dysregulation, and apoptosis. Vascular damage, ischemia and loss of blood brain barrier integrity contribute to destruction of brain tissue. This review focuses on the cellular damage incited during TBI and the frequently life-altering lasting effects of this destruction on vision, cognition, balance, and sleep. The wide range of visual complaints associated with TBI are addressed and repair processes where there is potential for intervention and neuronal preservation are highlighted.

Overview of systematic reviews: Management of common Traumatic Brain Injury-related complications

Background

Many clinical interventions are trialled to manage medical complications following Traumatic Brain Injury (TBI). However, published evidence for the effects of those clinical interventions is limited. This article is an overview of common complications and their management from published systematic reviews in TBI.

Methods and findings

A health science electronic database search for published systematic reviews for management of common complications in TBI was conducted in the last decade till 31st January 2021. Methodological quality and evidence were critically appraised using the Grading of Recommendations, Assessment, Development and Evaluations and Revised-Assessment of Multiple Systematic review tools. Overall, only six systematic reviews complied with search criteria, these evaluated fatigue, spasticity and post traumatic seizures (29 RCTs, 13 cohort studies, n = 5639 participants). No systematic reviews for other common TBI-related complications met criteria for this review. The included reviews varied from ‘moderate to high’ in methodological quality. The findings suggest beneficial treatment effect of anti-epileptic drugs (phenytoin/levetiracetam) compared with placebo in reducing early seizure incidence, but no significant benefit of phenytoin over levetiracetam, valproate, or neuroprotective agent for early or late posttraumatic seizures. There was ‘limited’ evidence for spasticity-related interventions, and ‘insufficient’ evidence of cardiorespiratory training on fatigue levels.

Conclusions

Despite the high prevalence and associated functional impact of TBI-related complications, there is limited evidence to guide treating clinicians for management of common TBI complications. More robust studies are needed to build evidence in this population.

Responsiveness of the Italian version of the Pediatric Quality of Life Multidimensional Fatigue Scale in adult inpatients with obesity

This study aimed to evaluate the responsiveness of the Italian version of the Paediatric Quality of Life Inventory Multidimensional Fatigue Scale (PedsQL-MFS) to changes in BMI, fatigue and depressive symptoms in adult inpatients with obesity. 198 adults (81% female, mean age = 44.7 years) with obesity completed the PedsQL-MFS, the Fatigue Severity Scale (FFS) and the Centre for Epidemiologic Studies Depression Scale (CESD) before and after completing a 3-week body weight reduction program. Internal responsiveness was measured via paired t-tests, standardized mean response (SMR) and Glass’s delta (d). Changes in FFS, CESD and BMI were used as anchors to categorize participants as “improved”, “unchanged” or “deteriorated”. External Responsiveness was assessed by comparing mean post-intervention PedsQL-MFS scores across change groups, adjusting for pre-intervention PedsQL-MFS scores and in area-under-curve (AUC) analysis. PedsQL-MFS Total, Sleep/Rest Fatigue and Cognitive Fatigue scores demonstrated significant reductions in response to an established body weight reduction program. Post-intervention PedsQL-MFS scale scores were lower among those who had improved on the CESD and FSS than among those whose CESD and FSS scores had not significantly changed. There was no difference in PedsQL-MFS scale scores according to whether participants had reduced their BMI by at least 5%. AUC analyses indicated that change in PedsQL-MFS scores was somewhat more predictive of improvement in CESD than FSS scores. The Italian version of the PedsQL-MFS demonstrated both internal and external responsiveness. It appeared more sensitive to improvement than deterioration in fatigue symptoms and its sensitivity to deterioration in depressive symptoms and weight loss could not be evaluated in the present study as there was no reliable deterioration in CESD scores and weight loss was modest. Future studies should include a control group to assess the sensitivity of the PedsQL-MFS more thoroughly.

Neurobiological Links between Stress, Brain Injury, and Disease

Stress, which refers to a combination of physiological, neuroendocrine, behavioral, and emotional responses to novel or threatening stimuli, is essentially a defensive adaptation under physiological conditions. However, strong and long-lasting stress can lead to psychological and pathological damage. Growing evidence suggests that patients suffering from mild and moderate brain injuries and diseases often show severe neurological dysfunction and experience severe and persistent stressful events or environmental stimuli, whether in the acute, subacute, or recovery stage. Previous studies have shown that stress has a remarkable influence on key brain regions and brain diseases. The mechanisms through which stress affects the brain are diverse, including activation of endoplasmic reticulum stress (ERS), apoptosis, oxidative stress, and excitatory/inhibitory neuron imbalance, and may lead to behavioral and cognitive deficits. The impact of stress on brain diseases is complex and involves impediment of recovery, aggravation of cognitive impairment, and neurodegeneration. This review summarizes various stress models and their applications and then discusses the effects and mechanisms of stress on key brain regions—including the hippocampus, hypothalamus, amygdala, and prefrontal cortex—and in brain injuries and diseases—including Alzheimer’s disease, stroke, traumatic brain injury, and epilepsy. Lastly, this review highlights psychological interventions and potential therapeutic targets for patients with brain injuries and diseases who experience severe and persistent stressful events.

Impact of Somatic Vulnerability, Psychosocial Robustness and Injury-Related Factors on Fatigue following Traumatic Brain Injury-A Cross-Sectional Study

Fatigue is a common symptom after traumatic brain injuries (TBI) and a crucial target of rehabilitation. The subjective and multifactorial nature of fatigue necessitates a biopsychosocial approach in understanding the mechanisms involved in its development. The aim of this study is to provide a comprehensive exploration of factors relevant to identification and rehabilitation of fatigue following TBI. Ninety-six patients with TBI and confirmed intracranial injuries were assessed on average 200 days post-injury with regard to injury-related factors, several patient-reported outcome measures (PROMS) of fatigue, neuropsychological measures, and PROMS of implicated biopsychosocial mechanisms. Factor analytic approaches yielded three underlying factors, termed Psychosocial Robustness, Somatic Vulnerability and Injury Severity. All three dimensions were significantly associated with fatigue in multiple regression analyses and explained 44.2% of variance in fatigue. Post hoc analyses examined univariate contributions of the associations between the factors and fatigue to illuminate the relative contributions of each biopsychosocial variable. Implications for clinical practice and future research are discussed.

Restraint Stress Delays the Recovery of Neurological Impairments and Exacerbates Brain Damages through Activating Endoplasmic Reticulum Stress-mediated Neurodegeneration/Autophagy/Apopotosis post Moderate Traumatic Brain Injury

Based on accumulating evidence, patients recovering from mild and moderate traumatic brain injury (TBI) often experience increased sensitivity to stressful events. However, few studies have assessed on the effects and pathophysiological mechanisms of stress on TBI. In the current study, using a mouse model of moderate TBI, we investigated whether restraint stress (RS) regulates secondary neurodegeneration and neuronal cell death, which are commonly associated with neurological dysfunctions. Our data showed that RS significantly reduced body weight recovery, delayed the recovery of neurological functions (motor function, cognitive function and anxiety-like behavior) and exacerbated the brain lesion volume after moderate TBI. Immunofluorescence results indicated that moderate TBI-induced cell insults and blood-brain barrier leakage were aggravated by RS. Further Western blotting experiments showed that RS activated endoplasmic reticulum (ER) stress excessively after moderate TBI and decreased the number of NeuN-positive cells, but increased the number of CHOP/NeuN-co-positive cells by performing immunostaining in the injured cortex after moderate TBI. Moreover, RS increased the ratios of CHOP/Aβ and CHOP/p-Tau co-positive cells in the injured cortex after moderate TBI. However, blocking ER stress with the classic ER stress inhibitor salubrinal remarkably decreased apoptosis and the levels of autophagy-related proteins in the mouse model of moderate TBI plus RS. Collectively, RS delays the recovery of neurological function and deteriorates morphological damage by excessively activating ER stress-mediated neurodegeneration, apoptosis and autophagy after moderate TBI. Thus, monitoring stress levels in patients recovering from non-severe TBI may merit consideration in the future.

Self- and Parent-Reported Fatigue 7 Years After Severe Childhood Traumatic Brain Injury: Results of the Traumatisme Grave de l'Enfant Prospective Longitudinal Study

OBJECTIVE

To investigate presence of and factors associated with self- and parent-reported fatigue 7 years after severe childhood traumatic brain injury (TBI) in the prospective longitudinal study TGE (Traumatisme Grave de l'Enfant-severe childhood trauma).

METHODS

Self-reports and/or parent reports on the Multidimensional Fatigue Scale were collected for 38 participants (aged 7-22 years) 7 years after severe childhood TBI, and 33 controls matched for age, gender, and parental educational level. The data collected included sociodemographic characteristics, age at injury and injury severity scores, overall disability (Glasgow Outcome Scale Extended), intellectual outcome (Wechsler scales), and questionnaires assessing executive functions, health-related quality of life, behavior, and participation.

RESULTS

Fatigue levels were significantly worse in the TBI than in the control group, especially for cognitive fatigue. Correlations of reported fatigue with age at injury, gender, TBI severity, and intellectual ability were moderate and often not significant. Fatigue was significantly associated with overall level of disability (Glasgow Outcome Scale Extended) and with all questionnaires completed by the same informant.

CONCLUSION

High levels of fatigue were reported by 30% to 50% of patients 7 years after a severe childhood TBI. Reported fatigue explained more than 60% of the variance of reported health-related quality of life by the same informant (patient or parent).

Cognitive fatigue in traumatic brain injury: a pilot study comparing state and trait fatigue

OBJECTIVE

Cognitive fatigue is a common and disabling symptom following a traumatic brain injury (TBI). Literature on cognitive fatigue has distinguished between two types of fatigue: "state" fatigue refers to the acute experience of fatigue, whereas "trait" fatigue refers to the susceptibility to fatigue over an extended period. However, it is not clear whether state and trait fatigue are distinguishable constructs. Here, we examine the relationship between state and trait fatigue in individuals with TBI, hypothesizing that trait and state measures assess different constructs.

PARTICIPANTS

Twenty-one participants with moderate-severe TBI were recruited.

DESIGN

Participants underwent a cognitively fatiguing task while in an MRI scanner and completed self-report measures examining trait and state fatigue.

RESULTS

No correlation was found between state and trait fatigue. However, the two measures of trait fatigue, Fatigue Severity Scale (FSS) and the Modified Fatigue Impact Scale (MFIS), correlated with one another; additionally only trait fatigue correlated with depression scores, consistent with the literature.

CONCLUSION

These findings suggest that trait and state fatigue may not be interdependent and that it is important to carefully define the type of fatigue under consideration when assessing fatigue in individuals with TBI.

Testosterone and Resting State Connectivity of the Parahippocampal Gyrus in Men With History of Deployment-Related Mild Traumatic Brain Injury

INTRODUCTION

The purpose of this study was to explore the effect of low testosterone level on whole-brain resting state (RS) connectivity in male veterans with symptoms such as sleep disturbance, fatiguability, pain, anxiety, irritability, or aggressiveness persisting after mild traumatic brain injury (mTBI). Follow-up analyses were performed to determine if sleep scores affected the results.

MATERIALS AND METHODS

In our cross-sectional design study, RS magnetic resonance imaging scans on 28 veterans were performed, and testosterone, sleep quality, mood, and post-traumatic stress symptoms were measured. For each participant, we computed the average correlation of each voxel's time-series with the rest of the voxels in the brain, then used AFNI's 3dttest++ on the group data to determine whether the effects of testosterone level on whole-brain connectivity were significant. We then performed follow-up region of interest-based RS analyses of testosterone, with and without sleep quality as a covariate. The study protocol was approved by the National Institute of Health's Combined Neuroscience Institutional Review Board.

RESULTS

Sixteen participants reported repeated blast exposure in theater, leading to symptoms; the rest reported exposure to a single blast or a nonblast TBI. Thirty-three percent had testosterone levels <300 ng/dL. Testosterone level was lower in participants who screened positive for post-traumatic stress disorder compared to those who screened negative, but it did not reach statistical significance. Whole-brain connectivity and testosterone level were positively correlated in the left parahippocampal gyrus (LPhG), especially in its connectivity with frontal areas, the lingual gyrus, cingulate, insula, caudate, and right parahippocampal gyrus. Further analysis revealed that the effect of testosterone on LPhG connectivity is only partially mediated by sleep quality. Sleep quality by itself had an effect on connectivity of the thalamus, cerebellum, precuneus, and posterior cingulate.

CONCLUSION

Lower testosterone levels were correlated with lower connectivity of the LPhG. Weaknesses of this study include a retrospective design based on self-report of mTBI and the lack of a control group without TBI. Without a control group or pre-injury testosterone measures, we were not able to attribute the rate of low testosterone in our participants to TBI per se. Also testosterone levels were checked only once. The high rate of low testosterone level that we found suggests there may be an association between low testosterone level and greater post-traumatic stress disorder symptoms following deployment, but the causality of the relationships between TBI and deployment stress, testosterone level, behavioral symptomatology, and LPhG connectivity remains to be determined. Our study on men with persistent symptoms postdeployment and post-mTBI may help us understand the role of low testosterone and sleep quality in persistent symptoms and may be important in developing therapeutic interventions. Our results highlight the role of the LPhG, as we found that whole-brain connectivity in that region was positively associated with testosterone level, with only a limited portion of that effect attributable to sleep quality.

Community Integration After Traumatic Brain Injury and Related Factors: A Study in the Nepalese Context

Introduction

Community integration is an essential component for rehabilitation among traumatic brain injury (TBI) survivors, which yields positive outcomes in terms of social activities, community participation, and productive work. A factor that usually facilitates community integration among TBI survivors is social support, whereas physical environment and fatigue are most often found as barriers.

Objectives

This study aimed to (1) describe the level of community integration, fatigue, physical environment, and social support of persons after TBI, and (2) examine the relationship between community integration and these three factors.

Methods

This is a descriptive correlational study. One hundred and twenty TBI survivors living in the communities of Province Number Three, Nepal were enrolled using the stratified sampling technique. The data were collected using the Community Integration Questionnaire, Modified Fatigue Impact Scale, Craig Hospital Inventory of Environmental Factors, and the Multidimensional Scale of Perceived Social Support. Descriptive statistics and Pearson's correlation were used to analyze the data.

Results

Community integration, fatigue, and physical environment showed a moderate level, while social support revealed a high level. Fatigue was significantly correlated with overall community integration, whereas physical environment was found to correlate with two subscales of community integration, home integration and productive activities.

Conclusion

To enhance the level of community integration among TBI survivors, health care providers, in particular rehabilitation nurses and community nurses, should plan and implement strategies such as follow-up appointments or continued rehabilitation at home.

Frequency of fatigue and its changes in the first 6 months after traumatic brain injury: results from the CENTER-TBI study

Background

Fatigue is one of the most commonly reported subjective symptoms following traumatic brain injury (TBI). The aims were to assess frequency of fatigue over the first 6 months after TBI, and examine whether fatigue changes could be predicted by demographic characteristics, injury severity and comorbidities.

Methods

Patients with acute TBI admitted to 65 trauma centers were enrolled in the study Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI). Subjective fatigue was measured by single item on the Rivermead Post-Concussion Symptoms Questionnaire (RPQ), administered at baseline, three and 6 months postinjury. Patients were categorized by clinical care pathway: admitted to an emergency room (ER), a ward (ADM) or an intensive care unit (ICU). Injury severity, preinjury somatic- and psychiatric conditions, depressive and sleep problems were registered at baseline. For prediction of fatigue changes, descriptive statistics and mixed effect logistic regression analysis are reported.

Results

Fatigue was experienced by 47% of patients at baseline, 48% at 3 months and 46% at 6 months. Patients admitted to ICU had a higher probability of experiencing fatigue than those in ER and ADM strata. Females and individuals with lower age, higher education, more severe intracranial injury, preinjury somatic and psychiatric conditions, sleep disturbance and feeling depressed postinjury had a higher probability of fatigue.

Conclusion

A high and stable frequency of fatigue was found during the first 6 months after TBI. Specific socio-demographic factors, comorbidities and injury severity characteristics were predictors of fatigue in this study.

Electronic supplementary material

The online version of this article (10.1007/s00415-020-10022-2) contains supplementary material, which is available to authorized users.

Factors associated with the remission of insomnia after traumatic brain injury: a traumatic brain injury model systems study

Objective: To examine the factors associated with the remission of insomnia by examining a sample of individuals who had insomnia within the first two years after traumatic brain injury (TBI) and assessing their status at a secondary time point.Design and Methods: Secondary data analysis from a multicenter longitudinal cohort study. A sample of 40 individuals meeting inclusion criteria completed a number of self-report scales measuring sleep/wake characteristics (Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Insomnia Severity Index, Sleep Hygiene Index), fatigue and depression (Multidimensional Assessment of Fatigue, Patient Health Questionnaire-9), and community participation (Participation Assessment with Recombined Tools-Objective). One cohort was followed at 1 and 2 years post-injury (n = 19) while a second cohort was followed at 2 and 5 years post-injury (n = 21).Results: Remission of insomnia was noted in 60% of the sample. Those with persistent insomnia had significantly higher levels of fatigue and depression at their final follow-up and poorer sleep hygiene across both follow-up time-points. A trend toward reduced community participation among those with persistent insomnia was also found.Conclusion: Individuals with persistent post-TBI insomnia had poorer psychosocial outcomes. The chronicity of post-TBI insomnia may be associated with sleep-related behaviors that serve as perpetuating factors.

Prevalence of Anterior Pituitary Dysfunction Twelve Months or More following Traumatic Brain Injury in Adults: A Systematic Review and Meta-Analysis

The objective of this study is to systematically review clinical studies that have reported on the prevalence of chronic post-traumatic brain injury anterior pituitary dysfunction (PTPD) 12 months or more following traumatic brain injury (TBI). We searched Medline, Embase, and PubMed up to April 2017 and consulted bibliographies of narrative reviews. We included cohort, case-control, and cross-sectional studies enrolling at least five adults with primary TBI in whom at least one anterior pituitary axis was assessed at least 12 months following TBI. We excluded studies in which other brain injuries were indistinguishable from TBI. Study quality was assessed using the Newcastle-Ottawa Scale (NOS) score. We also considered studies that determined growth hormone deficiency and adrenocorticotrophic hormone reserve using provocation test to be at low risk of bias. Data were extracted by four independent reviewers and assessed for risk of bias using a data extraction form. We performed meta-analyses using random effect models and assessed heterogeneity using the I² index. We identified 58 publications, of which 29 (2756 participants) were selected for meta-analysis. Twelve of these were deemed to be at low risk of bias and therefore "high-quality," as they had NOS scores greater than 8 and had used provocation tests. The overall prevalence of at least one anterior pituitary hormone dysfunction for all 29 studies was 32% (95% confidence interval [CI] 25-38%). The overall prevalence in the 12 high-quality studies was 34% (95% CI 27-42%). We observed significant heterogeneity that was not solely explained by the risk of bias. Studies with a higher proportion of participants with mild TBI had a lower prevalence of PTPD. Our results show that approximately one-third of TBI sufferers have persistent anterior pituitary dysfunction 12 months or more following trauma. Future research on PTPD should differentiate between mild and moderate/severe TBI.

A Systematic Review of Studies Using the Multidimensional Assessment of Fatigue Scale

PURPOSE

To review how the Multidimensional Assessment of Fatigue (MAF) has been used and evaluate its psychometric properties.

METHODS

We conducted a database search using "multidimensional assessment of fatigue" or "MAF" as key terms from 1993 to 2015, and located 102 studies.

RESULTS

Eighty-three were empirical studies and 19 were reviews/evaluations. Research was conducted in 17 countries; 32 diseases were represented. Nine language versions of the MAF were used. The mean of the Global Fatigue Index ranged from 10.9 to 49.4. The MAF was reported to be easy-to-use, had strong reliability and validity, and was used in populations who spoke languages other than English.

CONCLUSION

The MAF is an acceptable assessment tool to measure fatigue and intervention effectiveness in various languages, diseases, and settings across the world.

Measuring Fatigue in TBI: Development of the TBI-QOL Fatigue Item Bank and Short Form

OBJECTIVE

To develop a traumatic brain injury (TBI)-specific, item response theory (IRT)-calibrated Fatigue item bank, short form, and computer adaptive test (CAT) as part of the Traumatic Brain Injury-Quality of Life (TBI-QOL) measurement system.

SETTING

Five TBI Model Systems rehabilitation centers in the US PARTICIPANTS:: Adults with complicated mild, moderate, or severe TBI confirmed by medical record review.

DESIGN

Cross-sectional field testing via phone or in-person interview.

MAIN MEASURES

TBI-QOL Fatigue item bank, short form, and CAT.

RESULTS

A total of 590 adults with TBI completed 95 preliminary fatigue items, including 86 items from the Patient-Reported Outcomes Measurement Information System (PROMIS) and 9 items from the Quality of Life in Neurological Disorders (Neuro-QOL) system. Through 4 iterations of factor analysis, 22 items were deleted for reasons such as local item dependence, misfit, and low item-total correlations. Graded response model IRT analyses were conducted on the 73-item set, and Stocking-Lord equating was used to transform the item parameters to the PROMIS (general population) metric. A short form and CAT, which demonstrate similar reliability to the full item bank, were developed. Test-retest reliability of the CAT was established in an independent sample (Pearson's r and intraclass correlation coefficient = 0.82 [95% confidence interval: 0.72-0.88]).

CONCLUSIONS

The TBI-QOL Fatigue item bank, short form, and CAT provide rehabilitation researchers and clinicians with TBI-optimized tools for assessment of the patient-reported experience and impact of fatigue on individuals with TBI.

A Qualitative Study on the Transition Support Needs of Indigenous Australians Following Traumatic Brain Injury

Objective:

A growing body of qualitative literature globally describes post-hospital experiences during early recovery from a traumatic brain injury. For Indigenous Australians, however, little published information is available. This study aimed to understand the lived experiences of Indigenous Australians during the 6 months post-discharge, identify the help and supports accessed during transition and understand the gaps in service provision or difficulties experienced.

Methods and Procedure:

Semi-structured interviews were conducted at 6 months after hospital discharge to gain an understanding of the needs and lived experiences of 11 Aboriginal and Torres Strait Islander Australians who had suffered traumatic brain injury in Queensland and Northern Territory, Australia. Data were analysed using thematic analysis.

Results:

Five major themes were identified within the data. These were labelled ‘hospital experiences’, ‘engaging with medical and community-based supports’, ‘health and wellbeing impacts from the injury’, ‘everyday living’ and ‘family adjustments post-injury’.

Conclusions:

While some of the transition experiences for Indigenous Australians were similar to those found in other populations, the transition period for Indigenous Australians is influenced by additional factors in hospital and during their recovery process. Lack of meaningful interaction with treating clinicians in hospital, challenges managing direct contact with multiple service providers and the injury-related psychological impacts are some of the factors that could prevent Indigenous Australians from receiving the supports they require to achieve their best possible health outcomes in the long term. A holistic approach to care, with an individualised, coordinated transition support, may reduce the risks for re-admission with further head injuries.

The history of pituitary dysfunction after traumatic brain injury

PURPOSE

To estimate the total number of articles on traumatic brain injury (TBI)-related hypopituitarism and patients (including children and adolescents) with such disorder that were published until now, particularly after the author's review published on April 2000.

METHODS

Review of the literature retrievable on PubMed.

RESULTS

TBI-related hypopituitarism accounts for 7.2% of the whole literature on hypopituitarism published during the 18 years and half between May 2000 and October 2018. As a result, the total number of patients with TBI-related hypopituitarism now approximates 2200. A number of patients, both adults and children, continue to be published as case reports. Articles, including reviews and guidelines, have been published in national languages in order to maximize locally the information on TBI-related hypopituitarism. TBI-related hypopituitarism has been also studied in animals (rodents, cats and dogs).

CONCLUSIONS

The interest for the damage suffered by anterior pituitary as a result of TBI continues to remain high both in the adulthood and childhood.

Mechanisms underlying vulnerabilities after repeat mild traumatic brain injuries

Traumatic brain injury (TBI) has drawn national attention for its high incidence and mechanistic complexity. The majority of TBI cases are "mild" in nature including concussions and mild TBI (mTBI). Concussions are a distinct form of mTBI where diagnosis is difficult, quantification of the incidence is challenging and there is greater risk for subsequent injuries. While concussions occur in the general population, it has become a hallmark injury consistently observed among adolescent and young adult athletes and the risks for repeat TBI (rTBI) is significant. Clinical and experimental evidence shows that the magnitude and duration of deficits is dependent on the number and the interval between injuries. Several studies suggest that metabolic vulnerabilities after injury may contribute to the window for cerebral vulnerability from rTBI. In addition to metabolism, this review addresses how age, sex and hormones also play an important role in the response to repeat concussions. Understanding how these factors collectively contribute to concussion and rTBI recovery is critically important in establishing age/sex appropriate return to play guidelines, injury prevention, therapeutic interventions and mitigation of long-term consequences of rTBI.

The interplay between neuroendocrine and sleep alterations following traumatic brain injury

BACKGROUND

Sleep and endocrine disruptions are prevalent after traumatic brain injury (TBI) and are likely to contribute to morbidity.

OBJECTIVE

To describe the interaction between sleep and hormonal regulation following TBI and elucidate the impact that alterations of these systems have on cognitive responses during the posttraumatic chronic period.

METHODS

Review of preclinical and clinical literature describing long-lasting endocrine dysregulation and sleep alterations following TBI. The bidirectional relationship between sleep and hormones is described. Literature describing co-occurrence between sleep-wake disturbances and hormonal dysregulation will be presented. Review of literature describing cognitive effects of seep and hormones. The cognitive and functional impact of sleep disturbances and hormonal dysregulation is discussed within the context of TBI.

RESULTS/CONCLUSIONS

Sleep and hormonal alterations impact cognitive and functional outcome after TBI. Diagnosis and treatment of these disturbances will impact recovery following TBI and should be considered in the post-acute rehabilitative setting.

Sleep and fatigue after TBI

BACKGROUND

Whilst post traumatic brain injury fatigue (PTBIF) and sleep disturbance are common sequelae following brain injury, underlying mechanisms, and the potential for targeted interventions remain unclear.

OBJECTIVE

To present a review of recent studies exploring the epidemiology of PTBIF and sleep disturbance, the relationship and neuropsychological correlates of these issues, potential approaches to intervention, and implications for neurorehabilitation.

METHODS

A review of relevant literature was undertaken, with a focus on PTBIF relating to sleep disturbance, the neuropsychological correlates of these issues and implications for neurorehabilitation. This paper does not set out to provide a systematic review.

RESULTS

Multidimensional approaches to assessment and treatment of sleep disturbance and PTBIF are required.

CONCLUSIONS

There is a need for more robust findings in determining the complex nature of relationships between PTBIF, sleep disturbance, and correlates. Longitudinal prospective data is required to increase our understanding of the nature and course of PTBIF and sleep disturbance post TBI. Large scale clinical trials are required in evaluating the potential benefits of interventions.

Sex-related responses after traumatic brain injury: Considerations for preclinical modeling

Traumatic brain injury (TBI) has historically been viewed as a primarily male problem, since men are more likely to experience a TBI because of more frequent participation in activities that increase risk of head injuries. This male bias is also reflected in preclinical research where mostly male animals have been used in basic and translational science. However, with an aging population in which TBI incidence is increasingly sex-independent due to falls, and increasing female participation in high-risk activities, the attention to potential sex differences in TBI responses and outcomes will become more important. These considerations are especially relevant in designing preclinical animal models of TBI that are more predictive of human responses and outcomes. This review characterizes sex differences following TBI with a special emphasis on the contribution of the female sex hormones, progesterone and estrogen, to these differences. This information is potentially important in developing and customizing TBI treatments.

Pituitary dysfunction and association with fatigue in stroke and other acute brain injury

BACKGROUND

Poststroke fatigue (PSF) is a highly prevalent and debilitating condition. However, the etiology remains incompletely understood. Literature suggests the co-prevalence of pituitary dysfunction (PD) with stroke, and the question raises whether this could be a contributing factor to the development of PSF. This study reviews the prevalence of PD after stroke and other acquired brain injuries and its association with fatigue.

SUMMARY

We performed a bibliographic literature search of MEDLINE and EMBASE databases for English language studies on PD in adult patients with stroke, traumatic brain injury (TBI) or aneurysmatic subarachnoid hemorrhage (aSAH). Forty-two articles were selected for review. Up to 82% of patients were found to have any degree of PD after stroke. Growth hormone deficiency was most commonly found. In aSAH and TBI, prevalences up to 49.3% were reported. However, data differed widely between studies, mostly due to methodological differences including the diagnostic methods used to define PD and the focus on the acute or chronic phase. Data on PD and outcome after stroke, aSAH and TBI are conflicting. No studies were found investigating the association between PD and PSF. Data on the association between PD and fatigue after aSAH and TBI were scarce and conflicting, and fatigue is rarely been investigated as a primary end point.

KEY MESSAGES

Data according to the prevalence of PD after stroke and other acquired brain injury suggest a high prevalence of PD after these conditions. However, the clinical relevance and especially the association with fatigue need to be established.

Traumatic Brain Injury: At the Crossroads of Neuropathology and Common Metabolic Endocrinopathies

Building on the seminal work by Geoffrey Harris in the 1970s, the neuroendocrinology field, having undergone spectacular growth, has endeavored to understand the mechanisms of hormonal connectivity between the brain and the rest of the body. Given the fundamental role of the brain in the orchestration of endocrine processes through interactions among neurohormones, it is thus not surprising that the structural and/or functional alterations following traumatic brain injury (TBI) can lead to endocrine changes affecting the whole organism. Taking into account that systemic hormones also act on the brain, modifying its structure and biochemistry, and can acutely and chronically affect several neurophysiological endpoints, the question is to what extent preexisting endocrine dysfunction may set the stage for an adverse outcome after TBI. In this review, we provide an overview of some aspects of three common metabolic endocrinopathies, e.g., diabetes mellitus, obesity, and thyroid dysfunction, and how these could be triggered by TBI. In addition, we discuss how the complex endocrine networks are woven into the responses to sudden changes after TBI, as well as some of the potential mechanisms that, separately or synergistically, can influence outcomes after TBI.

An update on diagnostic and prognostic biomarkers for traumatic brain injury

INTRODUCTION

Traumatic brain injury (TBI) is a major worldwide neurological disorder of epidemic proportions. To date, there are still no FDA-approved therapies to treat any forms of TBI. Encouragingly, there are emerging data showing that biofluid-based TBI biomarker tests have the potential to diagnose the presence of TBI of different severities including concussion, and to predict outcome. Areas covered: The authors provide an update on the current knowledge of TBI biomarkers, including protein biomarkers for neuronal cell body injury (UCH-L1, NSE), astroglial injury (GFAP, S100B), neuronal cell death (αII-spectrin breakdown products), axonal injury (NF proteins), white matter injury (MBP), post-injury neurodegeneration (total Tau and phospho-Tau), post-injury autoimmune response (brain antigen-targeting autoantibodies), and other emerging non-protein biomarkers. The authors discuss biomarker evidence in TBI diagnosis, outcome prognosis and possible identification of post-TBI neurodegernative diseases (e.g. chronic traumatic encephalopathy and Alzheimer's disease), and as theranostic tools in pre-clinical and clinical settings. Expert commentary: A spectrum of biomarkers is now at or near the stage of formal clinical validation of their diagnostic and prognostic utilities in the management of TBI of varied severities including concussions. TBI biomarkers could serve as a theranostic tool in facilitating drug development and treatment monitoring.

The effects of post-traumatic depression on cognition, pain, fatigue, and headache after moderate-to-severe traumatic brain injury: a thematic review

BACKGROUND

Post-traumatic depression (PTD) is one of the most common secondary complications to develop after moderate-to-severe traumatic brain injury (TBI). However, it rarely manifests singularly, and often co-occurs with other common TBI impairments.

OBJECTIVE

The objective of this thematic review is to evaluate studies examining the relationships between PTD and cognition, fatigue, pain, and headache among individuals with moderate-to-severe TBI.

RESULTS

We reviewed 16 studies examining the relationship between PTD and cognition (five articles), fatigue (five articles), pain (four articles), and headache (two articles). Two studies failed to identify the significant associations between PTD and neuropsychological test performance, while one study found a positive association. Two other studies found that early PTD was associated with later executive dysfunction. Studies on fatigue suggest it is a cause, not consequence, of PTD. Individuals with PTD tended to report more pain than those without PTD. Studies examining relationships between PTD and post-traumatic headache were equivocal.

CONCLUSIONS

Studies evaluating the effects of PTD on common TBI impairments have yielded mixed results. Evidence suggests PTD precedes the development of executive dysfunction, and a strong link exists between fatigue and PTD, with fatigue preceding PTD. Future prospective studies evaluating PTD relationships to pain and headache are warranted to elucidate causality.

Study of Fatigue and Associated Factors in Traumatic Brain Injury and Its Correlation with Insomnia and Depression

Introduction:

Fatigue has been cited as a common problem associated with traumatic brain injury. A positive association of fatigue has been suggested with insomnia and depression which are also considered to be significantly associated with traumatic brain injury.

Aims and Objectives:

The present study in post-traumatic brain injury patients is planned to assess the prevalence of fatigue, depression and insomnia, the correlation of fatigue with depression and insomnia and the risk factors associated with fatigue.

Material and Methodology:

Total 100 patients were recruited in the present study. Interview was focused on assessment of severity of traumatic brain injury, fatigue, insomnia and depression using Glasgow Coma Scale, Fatigue Severity Scale, Insomnia Severity Index and Patients Health Questionnaire(PHQ-9) respectively.

Results:

Prevalence of depression was found 84% while that of fatigue and insomnia was 50% and 49% respectively. All patients with fatigue had depression whereas those patients without fatigue were also found to have depression (68%) and this correlation was found statistically significant. Similarly, insomnia was reported in 70% of patients who were fatigued against 28% of patients with no fatigue. This was also found statistically significant (P <0.0002).

Conclusion:

Fatigue in common in post TBI patients. Insomnia and depression are closely associated with fatigue. Clinical and research investigations of fatigue in post-traumatic brain injury should include concomitant screening for treatable depressive symptoms and sleep disorders.

Prevalence and severity of fatigue in adolescents and young adults with acquired brain injury: A nationwide study

Objective: To investigate the prevalence and severity of fatigue in adolescents and young adults with acquired brain injury (ABI) compared with healthy controls (HCs) and to examine associations between fatigue and gender, age and level of education. Methods: This cross-sectional study included 15-30 year old patients with ABI and a convenience sample of 15-30 year old HCs. All participants completed the 20-item Multidimensional Fatigue Inventory (MFI-20). Pathological fatigue was defined as "General Fatigue" ≥12. Adjusted mean differences between groups were calculated using multivariate analysis of covariance (MANCOVA). The adjusted prevalence proportion ratio (PPR_adj) of pathological fatigue was calculated using Poisson regression. Results: The patients (n = 334) had higher scores than the HCs (n = 168) on all MFI-20 subscales with adjusted mean differences ranging from 1.7 to 4.7 and a higher prevalence of pathological fatigue (73% versus 29%), PPR_adj 2.7 (95% confidence interval 2.1-3.5). Female patients experienced more fatigue than males on the "General Fatigue" and "Reduced Activity" subscales, while no gender differences were found in the HC group. Patients and HCs with elementary education had elevated scores on the "Reduced Activity" and "Mental Fatigue" subscales. Age was not associated with any of the subscale scores. Conclusion: Young patients with ABI had markedly higher prevalence and severity of fatigue than HCs. Age (15-30 years) was not associated with fatigue. No clear patterns of associations were evident with gender and level of education. Abbreviations: ABI: acquired brain injury; CI: confidence interval; GF: general fatigue; GOSE: Glasgow Outcome Scale Extended; HC: healthy control; MANCOVA: multivariate analysis of covariance; MF: mental fatigue; MFI-20: Multidimensional Fatigue Inventory-20; PF: physical fatigue; RA: reduced activity; RM: reduced motivation; TBI: traumatic brain injury.

Neuropsychology of traumatic brain injury: An expert overview

Traumatic brain injury (TBI) is a serious healthcare problem, and this report is a selective review of recent findings on the epidemiology, pathophysiology and neuropsychological impairments following TBI. Patients who survive moderate-to-severe TBI frequently suffer from a wide range of cognitive deficits and behavioral changes due to diffuse axonal injury. These deficits include slowed information-processing and impaired long-term memory, attention, working memory, executive function, social cognition and self-awareness. Mental fatigue is frequently also associated and can exacerbate the consequences of neuropsychological deficits. Personality and behavioral changes can include combinations of impulsivity and apathy. Even mild TBI raises specific problems: while most patients recover within a few weeks or months, a minority of patients may suffer from long-lasting symptoms (post-concussion syndrome). The pathophysiology of such persistent problems remains a subject of debate, but seems to be due to both injury-related and non-injury-related factors.

Sleep-Wake Disturbances After Traumatic Brain Injury: Synthesis of Human and Animal Studies

Sleep-wake disturbances following traumatic brain injury (TBI) are increasingly recognized as a serious consequence following injury and as a barrier to recovery. Injury-induced sleep-wake disturbances can persist for years, often impairing quality of life. Recently, there has been a nearly exponential increase in the number of primary research articles published on the pathophysiology and mechanisms underlying sleep-wake disturbances after TBI, both in animal models and in humans, including in the pediatric population. In this review, we summarize over 200 articles on the topic, most of which were identified objectively using reproducible online search terms in PubMed. Although these studies differ in terms of methodology and detailed outcomes; overall, recent research describes a common phenotype of excessive daytime sleepiness, nighttime sleep fragmentation, insomnia, and electroencephalography spectral changes after TBI. Given the heterogeneity of the human disease phenotype, rigorous translation of animal models to the human condition is critical to our understanding of the mechanisms and of the temporal course of sleep-wake disturbances after injury. Arguably, this is most effectively accomplished when animal and human studies are performed by the same or collaborating research programs. Given the number of symptoms associated with TBI that are intimately related to, or directly stem from sleep dysfunction, sleep-wake disorders represent an important area in which mechanistic-based therapies may substantially impact recovery after TBI.

Impact of sleep, fatigue, and systemic inflammation on neurocognitive and behavioral outcomes in long-term survivors of childhood acute lymphoblastic leukemia

BACKGROUND

Long-term survivors of childhood acute lymphoblastic leukemia (ALL) are at risk for neurocognitive impairment, which may be associated with fatigue, sleep problems, systemic inflammation, and oxidative stress. We examined these associations among survivors of childhood ALL treated with chemotherapy only.

METHODS

Survivors of childhood ALL (male, n = 35 and female, n = 35; mean age, 14.3 years [standard deviation, 4.7 years] and mean years from diagnosis, 7.4 years [standard deviation, 1.9 years]) completed neurocognitive testing, behavioral ratings, and reported sleep quality and fatigue symptoms 5 years after diagnosis. Serum was collected concurrently and assayed for interleukin (IL)-1β and IL-6, tumor necrosis factor α (TNF-α), high-sensitivity C-reactive protein (hsCRP), malondialdehyde, myeloperoxidase, and oxidized low-density lipoprotein. General linear modeling was used to assess associations among biomarkers and functional outcomes, adjusting for age and stratified by sex.

RESULTS

Survivors performed worse than population norms on executive function and processing speed and reported more behavioral problems (P < .05 adjusted for multiple comparison). In female survivors, fatigue was associated with poor executive function (r = 0.41; P = .02), processing speed (r = 0.56; P < .001), and attention (r = 0.36-0.55; P < .05). Female survivors with frequent nighttime awakening displayed more inattention (P = .01), hyperactivity (P = .03), and aggression (P = .01). Worse executive function, processing speed, and behavioral symptoms were observed in female survivors with higher levels of IL-6, IL-1β, and hsCRP (P < .05). Male survivors with high levels of TNF-α demonstrated worse organization (P = .03), but no significant associations between neurocognitive outcomes and sleep/fatigue measures were observed.

CONCLUSION

Neurocognitive function in female survivors of childhood ALL appears more susceptible to the effects of sleep disturbance and fatigue. Systemic inflammation may play a role in neurocognitive impairment and behavioral symptoms. Cancer 2017;123:3410-9. © 2017 American Cancer Society.

Unintentional injuries after TBI: Potential risk factors, impacts, and prevention

BACKGROUND

The top three causes of fatal unintentional injuries are falls, motor vehicle crashes, and being struck against or struck by objects or persons. These etiologies also happen to be the leading causes of TBI, a serious public health problem, in the US. Reduced cognitive functioning, poor decision making, increased risk taking, disinhibition, diminished safety skills and substance use, place individuals with TBI at an increased risk for subsequent unintentional injuries. The caregiving, psychological, social and financial burden of initial injuries is enormous. Unintentional injuries post-TBI add to that burden significantly. Many unintentional injuries can be prevented with simple education and environment and lifestyle changes. Injury prevention requires collaboration among many.

OBJECTIVE

This literature review will share information regarding potential triggers or causes of unintentional injuries after TBI to identify potential issues. The many impacts of these injuries will be reviewed. Best practices in prevention will be presented.

CONCLUSION

Ultimately, education, discussion, and awareness across multiple stakeholders can aid in preventing unintentional injuries after TBI.

A randomised control trial of walking to ameliorate brain injury fatigue: a NIDRR TBI model system centre-based study

Fatigue is one of the most commonly reported sequelae after traumatic brain injury (TBI). This study evaluated the impact of a graduated physical activity programme on fatigue after TBI. Using a prospective randomised single-blind crossover design, 123 individuals with TBI, over the age of 18, were enrolled. Interventions included a home-based walking programme utilising a pedometer to track daily number of steps at increasing increments accompanied by tapered coaching calls over a 12-week period. Nutritional counselling with the same schedule of coaching calls served as the control condition. Main outcome measures included: the Global Fatigue Index (GFI), the Barrow Neurological Institute (BNI) Fatigue Scale Overall Severity Index Score, and the Multidimensional Fatigue Inventory (MFI). Step counts improved over time regardless of group assignment. The walking intervention led to a decrease in GFI, BNI Total, and MFI General scores. Participants reported less fatigue at the end of the active part of the intervention (24 weeks) and after a wash out period (36 weeks) as measured by the BNI Overall. The study suggests that walking can be used as an efficient and cost-effective tool to improve fatigue in persons who have sustained a TBI.