The experience of fatigue in the first 2 years after moderate-to-severe traumatic brain injury: a preliminary report

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.

Biopsychosocial correlates of fatigue in young adult survivors of childhood traumatic brain injury: A prospective cohort study

This prospective cohort study aimed to evaluate the potential role of injury, socio-demographic and individual psychological factors in predicting long-term fatigue outcomes in young adult survivors of childhood TBI at 16-years post-injury. The study included 51 young adults diagnosed with childhood TBI from 2-12 years of age. Twenty age-and-sex-matched controls were included for comparison. Findings showed that almost one-in-four TBI participants (24%) endorsed clinically elevated fatigue at 16-years post-injury. Despite the relatively large proportion of TBI participants endorsing clinically significant fatigue, group comparisons revealed that the TBI and control groups did not significantly differ on fatigue symptom severity or rates of clinically elevated fatigue. For the TBI group, post-injury fatigue was significantly associated with socio-demographic and psychological factors, including lower educational level, higher depression symptom severity, and more frequent substance use. Higher fatigue was also associated with lower self-reported quality of life (QoL) in the physical, psychological, and environmental domains, even after controlling for depressive symptom severity, socio-demographic, and injury-related factors. Overall, findings show that a substantial proportion of young adults with a history of childhood TBI experience clinically elevated fatigue at 16-years post-injury. Identification and treatment of modifiable risk-factors (e.g. depression symptoms, substance use) has potential to reduce fatigue.

Self-reported Fatigue was Associated with Increased White-matter Alterations in Long-term Traumatic Brain Injury and Posttraumatic Stress Disorder Patients

Fatigue is a long-lasting problem in traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD), with limited research that investigated the fatigue-related white-matter changes within TBI and/or PTSD cohorts. This exploratory cross-sectional study used diffusion tensor imaging (DTI) and neuropsychological data collected from 153 male Vietnam War veterans, as part of the Alzheimer's Disease Neuroimaging Initiative - Department of Defense, and were divided clinically into control veterans, PTSD, TBI, and with both TBI and PTSD (TBI + PTSD). The existence of fatigue was defined by the question "Do you often feel tired, fatigued, or sleepy during the daytime?". DTI data were compared between fatigue and non-fatigue subgroups in each clinical group using tract-based spatial statistics voxel-based differences. Fatigue was reported in controls (29.55%), slightly higher in TBI (52.17%, PBenf = 0.06), and significantly higher in both TBI + PTSD (66.67%, PBenf = 0.001) and PTSD groups (79.25%, PBenf < 0.001). Compared to non-fatigued subgroups, no white-matter differences were observed in the fatigued subgroups of control or TBI, while the fatigued PTSD subgroup only showed increased diffusivity measures (i.e., radial and axial), and the fatigued TBI + PTSD subgroup showed decreased fractional anisotropy and increased diffusivity measures (PFWE ≤ 0.05). The results act as preliminary findings suggesting fatigue to be significantly reported in TBI + PTSD and PTSD decades post-trauma with a possible link to white-matter microstructural differences in both PTSD and TBI + PTSD. Future studies with larger cohorts and detailed fatigue assessments would be required to identify the white-matter changes associated with fatigue in these cohorts.

Traumatic brain injury as a chronic disease: insights from the United States Traumatic Brain Injury Model Systems Research Program

Traumatic brain injury (TBI) is a global health priority, associated with substantial burden. Historically conceptualised as an injury event with finite recovery, TBI is now recognised as a chronic condition that can affect multiple domains of health and function, some of which might deteriorate over time. Many people who have had a TBI remain moderately to severely disabled at 5 years, are rehospitalised up to 10 years post-injury, and have a reduced lifespan relative to the general population. Understanding TBI as a chronic disease process can be highly informative for optimising care, which has traditionally focused on acute care. Chronic brain injury care models must be informed by a holistic understanding of long-term outcomes and the factors that can affect how care needs evolve over time. The United States Traumatic Brain Injury Model Systems of Care follows up individuals with moderate-to-severe TBI for over 30 years, allowing characterisation of the chronic (2-30 years or more post injury) functional, cognitive, behavioural, and social sequelae experienced by individuals who have had a moderate-to-severe TBI and the implications for their health and quality of life. Older age, social determinants of health, and lower acute functional status are associated with post-recovery deterioration, while younger age and greater functional independence are associated with risky health behaviours, including substance misuse and re-injury. Systematically collected data on long-term outcomes across multiple domains of health and function are needed worldwide to inform the development of models for chronic disease management, including the proactive surveillance of commonly experienced health and functional challenges.

White matter hyperintensities increases with traumatic brain injury severity: associations to neuropsychological performance and fatigue

Objective: To examine the prevalence of white matter hyperintensities (WMHs) in patients with traumatic brain injury (TBI) as compared to healthy controls, and to investigate whether there is an association between WMH lesion burden and performance on neuropsychological tests in patients with TBI.Methods: A total of 59 patients with TBI and 27 age- and gender-matched healthy controls underwent thorough neuropsychological testing and magnetic resonance imaging. The quantification of WMH lesions was performed using the fully automated Lesion Segmentation Tool.Results: WMH lesions were more common in patients with TBI than in healthy controls (p = .032), and increased with higher TBI severity (p = .025). Linear regressions showed that WMH lesions in patients with TBI were not related to performance on any neuropsychological tests (p > .05 for all). However, a negative relationship between number of WMH lesions in patients with TBI and self-assessed fatigue was found (r = - 0.33, p = .026).Conclusion: WMH lesions are more common in patients with TBI than in healthy controls, and WMH lesions burden increases with TBI severity. These lesions could not explain decreased cognitive functioning in patients with TBI but did relate to decreased self-assessment of fatigue after TBI.

Insula and putamen centered functional connectivity networks reflect healthy agers' subjective experience of cognitive fatigue in multiple tasks

Cognitive fatigue (CF) impairs ability to perform daily activities, is a common complaint of aging and a symptom of multiple neurological conditions. However, knowledge of the neural basis of CF is limited. This is partially because CF is difficult to systematically modulate in brain imaging experiments. The most common approach has been to scan brain activity during effortful cognitive tasks. Consequently, neural correlates of CF tend to be task-specific and may vary across tasks. This makes it difficult to know how results generalize across studies and is outside the subjective experience of CF which tends to be similar in different tasks. It has been hypothesized that the subjective experience of CF might arise from domain general systems monitoring and acting on energy depletion in task specific circuits. Direct supporting neural evidence is lacking. By repeatedly scanning aging individuals undertaking four different tasks using functional Magnetic Resonance Imaging and referencing scans to detailed CF self-ratings taken before and after scanning, we sought task-general correlates of CF. We ran a data-driven representational similarity analysis, treating each brain region as a candidate CF functional connectivity hub, and correlating inter-participant differences in hub-based connectivity patterns with inter-participant differences in self-rated CF-profiles (a pattern of ratings across 18 questions). Both right insula and right putamen-based network connectivity patterns reflected CF across all tasks and could underpin subjective experience of CF.

Using Functional Magnetic Resonance Imaging to Detect Chronic Fatigue in Patients With Previous Traumatic Brain Injury: Changes Linked to Altered Striato-Thalamic-Cortical Functioning

OBJECTIVE

To investigate whether functional magnetic resonance imaging (fMRI) can be used to detect fatigue after traumatic brain injury (TBI).

SETTING

Neurorehabilitation clinic.

PARTICIPANTS

Patients with TBI (n = 57) and self-experienced fatigue more than 1 year postinjury, and age- and gender-matched healthy controls (n = 27).

MAIN MEASURES

Self-assessment scales of fatigue, a neuropsychological test battery, and fMRI scanning during performance of a fatiguing 27-minute attention task.

RESULTS

During testing within the fMRI scanner, patients showed a higher increase in self-reported fatigue than controls from before to after completing the task (P < .001). The patients also showed lower activity in several regions, including bilateral caudate, thalamus, and anterior insula (all P < .05). Furthermore, the patients failed to display decreased activation over time in regions of interest: the bilateral caudate and anterior thalamus (all P < .01). Left caudate activity correctly identified 91% of patients and 81% of controls, resulting in a positive predictive value of 91%.

CONCLUSION

The results suggest that chronic fatigue after TBI is associated with altered striato-thalamic-cortical functioning. It would be of interest to study whether fMRI can be used to support the diagnosis of chronic fatigue in future studies.

Psychometric Characteristics of the Insomnia Severity Index in Veterans With History of Traumatic Brain Injury

OBJECTIVE/BACKGROUND

The Insomnia Severity Index (ISI) is a widely used self-report measure of insomnia symptoms. However, to date this measure has not been validated or well-characterized in veterans who have experienced traumatic brain injury (TBI). This study assessed the psychometric properties and convergent, divergent, construct, and discriminate validity of the ISI in veterans with a history of TBI.

PARTICIPANTS

Eighty-three veterans with history of TBI were seen in the VA San Diego Healthcare System as part of a research protocol.

METHODS

Measures included the ISI, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale, Neurobehavioral Symptom Inventory, Beck Depression Inventory-II, Beck Anxiety Inventory, and PTSD Checklist-Military Version.

RESULTS

The ISI demonstrated moderate to strong or excellent convergent and divergent validity. A principal component analysis indicated a single construct with excellent internal consistency (Cronbach's alpha = 0.92). In exploratory analyses, the ISI discriminated well between those with (73%) and without (27%) sleep disturbance based on the PSQI.

CONCLUSIONS

Results from this study indicate validity of the ISI in assessing insomnia in veterans with history of TBI and suggest a cutoff score not dissimilar from non-TBI populations. Findings from this study can help inform clinical applicability of the ISI, as well as future studies of insomnia in TBI.

Randomised controlled trial of a self-guided online fatigue intervention in multiple sclerosis

OBJECTIVE

Fatigue is a major disabling symptom in many chronic diseases including multiple sclerosis (MS), but treatment options are limited.Here, we tested the effectiveness of a self-guided , interactive, online fatigue management programme (ELEVIDA) based on principles of cognitive behavioural therapy (CBT) and related psychotherapeutic approaches (eg, mindfulness) for reducing fatigue in MS.

METHODS

Patients with MS and self-reported fatigue were recruited via the website of the German MS Society and assigned via an automated randomisation generator (1:1, no blocking or stratification) to a 12-week online intervention (ELEVIDA, n=139, 82% female, mean age 40.8, median patient determined disease steps (PDDS) 3.0) or a waitlist control group (n=136, 79% female, mean age 41.9, median PDDS 3.0). The primary outcome was the Chalder Fatigue Scale. Outcomes were assessed at baseline, at week 12 (postintervention) and at follow-up (week 24).

RESULTS

Compared with the control group, significantly greater reductions in Chalder Fatigue Scale scores were seen in the ELEVIDA group at week 12 (primary endpoint, intention-to-treat analysis: between-group mean difference 2.74 points; 95% CI 1.16 to 4.32; p=0.0007; effect size d=0.53), with effects sustained at week 24 (intention-to-treat analysis: between-group mean difference 2.19 points; 95% CI 0.57 to 3.82; p=0.0080).

CONCLUSIONS

Our trial provides evidence for the effectiveness of a self-guided , internet-based intervention to reduce fatigue in MS. Interventions such as ELEVIDA may be a suitable low barrier, cost-effective treatment option for MS fatigue.

TRIAL REGISTRATION NUMBER

ISRCTN registry (number ISRCTN25692173).

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.

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.

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.

Cognitive Behavior Therapy to Treat Sleep Disturbance and Fatigue After Traumatic Brain Injury: A Pilot Randomized Controlled Trial

OBJECTIVE

To evaluate the efficacy of adapted cognitive behavioral therapy (CBT) for sleep disturbance and fatigue in individuals with traumatic brain injury (TBI).

DESIGN

Parallel 2-group randomized controlled trial.

SETTING

Outpatient therapy.

PARTICIPANTS

Adults (N=24) with history of TBI and clinically significant sleep and/or fatigue complaints were randomly allocated to an 8-session adapted CBT intervention or a treatment as usual (TAU) condition.

INTERVENTIONS

Cognitive behavior therapy.

MAIN OUTCOME MEASURES

The primary outcome was the Pittsburgh Sleep Quality Index (PSQI) posttreatment and at 2-month follow-up. Secondary measures included the Insomnia Severity Index, Fatigue Severity Scale, Brief Fatigue Inventory (BFI), Epworth Sleepiness Scale, and Hospital Anxiety and Depression Scale.

RESULTS

At follow-up, CBT recipients reported better sleep quality than those receiving TAU (PSQI mean difference, 4.85; 95% confidence interval [CI], 2.56-7.14). Daily fatigue levels were significantly reduced in the CBT group (BFI difference, 1.54; 95% CI, 0.66-2.42). Secondary improvements were significant for depression. Large within-group effect sizes were evident across measures (Hedges g=1.14-1.93), with maintenance of gains 2 months after therapy cessation.

CONCLUSIONS

Adapted CBT produced greater and sustained improvements in sleep, daily fatigue levels, and depression compared with TAU. These pilot findings suggest that CBT is a promising treatment for sleep disturbance and fatigue after TBI.

Predictors of cognitive and physical fatigue in post-acute mild-moderate traumatic brain injury

Post-traumatic fatigue (PTF) is a common, disabling, and often chronic symptom following traumatic brain injury (TBI). Yet, the impact of chronic cognitive and physical fatigue and their associations with psychiatric, sleep, cognitive, and psychosocial sequelae in mild-moderate TBI remain poorly understood. Sixty Veterans with a history of mild-moderate TBI and 40 Veteran controls (VC) were administered the Modified Fatigue Impact Scale, a validated measure of TBI-related cognitive and physical fatigue as well as measures of neuropsychiatric, psychosocial, sleep, and objective cognitive functioning. Compared to VC, TBI Veterans endorsed significantly greater levels of cognitive and physical fatigue. In TBI, psychiatric symptoms, sleep disturbance, and post-traumatic amnesia (PTA) were associated with both cognitive and physical fatigue, while loss of consciousness (LOC) and poor attention/processing speed were related to elevations in cognitive fatigue only. In regression analyses, anxiety, sleep disturbance, and LOC significantly predicted cognitive fatigue, while only post-traumatic stress symptoms and PTA contributed to physical fatigue. Cognitive and physical fatigue are problematic symptoms following mild-moderate TBI that are differentially associated with specific injury and psychiatric sequelae. Findings provide potential symptom targets for interventions aimed at ameliorating fatigue, and further underscore the importance of assessing and treating fatigue as a multi-dimensional symptom following TBI.

The effect of hypopituitarism on fatigue after subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Aneurysmal subarachnoid hemorrhage (SAH) survivors often complain of fatigue, which is disabling. Fatigue is also a common symptom of pituitary dysfunction (PD), in particular in patients with growth hormone deficiency (GHD). A possible association between fatigue after SAH and long-term pituitary deficiency in SAH survivors has not yet been established.

METHODS

A single center observational study was conducted amongst 84 aneurysmal SAH survivors to study the relationship between PD and fatigue over time after SAH, using mixed model analysis. Fatigue was measured with the Fatigue Severity Scale and its relationships with other clinical variables were studied.

RESULTS

Three-quarters of respondents (76%) have pathological fatigue directly after SAH and almost two-thirds (60%) of patients still have pathological levels of fatigue after 14 months. The severity of SAH measured with a World Federation of Neurosurgical Societies (WFNS) score higher than 1 (P = 0.008) was associated with long-term fatigue. There is no statistically significant effect of PD (P = 0.8) or GHD (P = 0.23) on fatigue in SAH survivors over time.

CONCLUSIONS

Fatigue is a common symptom amongst SAH survivors. WFNS is a usable clinical determinant of fatigue in SAH survivors. Neither PD nor GHD has a significant effect on long-term fatigue after SAH.

Fatigue in the first year after traumatic brain injury: course, relationship with injury severity, and correlates

The objectives of this study were to document the evolution of fatigue in the first year after traumatic brain injury (TBI), and to explore correlates of fatigue. Participants were 210 adults who were hospitalised following a TBI. They completed questionnaires 4, 8, and 12 months post-injury, including the Multidimensional Fatigue Inventory (MFI). Participants with severe TBI presented greater mental and physical fatigue, and reduced activity compared to participants with moderate TBI. For all MFI subscales except reduced motivation, the general pattern was a reduction of fatigue levels over time after mild TBI, an increase of fatigue after severe TBI, and stable fatigue after moderate TBI. Fatigue was significantly associated with depression, insomnia, cognitive difficulties, and pain at 4 months; the same variables and work status at 8 months; and depression, insomnia, cognitive difficulties, and work status at 12 months. These findings suggest that injury severity could have an impact on the course of fatigue in the first year post-TBI. Depression, insomnia, and cognitive difficulties remain strong correlates of fatigue, while for pain and work status the association with fatigue evolves over time. This could influence the development of intervention strategies for fatigue, implemented at specific times for each severity subgroup.

Why stay home? Temporal association of pain, fatigue and depression with being at home

BACKGROUND

Community participation is important to most people with disabilities despite the fact that common secondary conditions like pain, fatigue and depression may increase the difficulty of leaving home. Despite decades of research on these secondary conditions, little is known about how they are associated with being at home.

OBJECTIVE

We used Ecological Momentary Assessment data to examine within subject fluctuation in these secondary conditions to examine their effect on the likelihood that participants remain at or return home.

METHODS

Participants (n = 139) were recruited from a population based sampling frame to complete an Ecological Momentary Assessment that queried their location and experience with secondary conditions six times a day for two weeks.

RESULTS

Between subjects secondary condition ratings averaged across time periods indicated that pain and depression were associated with the share of measurement periods that respondents reported being at home. Within subject results indicated that a standard unit increase in pain, fatigue and depression was associated with being home one to two days later. Within day results indicated that increases in pain and fatigue were associated with increased likelihood of being home later, but increases in depression were associated with lower likelihood of being home later.

CONCLUSION

These results suggest there may be a complicated relationship among these secondary conditions and community participation with effects observed both across and within days. One interpretation suggests that secondary condition severity is tempered by adjusting participation. These results may have implications for intervening on these secondary conditions.

Accommodation of workers with chronic neurologic disorders

The ability to work is important to those with chronic neurologic disorders (CND) and to the aging workforce. Many signs and symptoms are similar in those with CND and normal aging, but may interfere with the ability to work if not appropriately accommodated. This requires the healthcare provider to recognize the specific features of the CND that interferes with work and how it can be accommodated. Review of the American with Disabilities Act and the subsequent amendment informs the healthcare provider as to what is covered under the law and how the disability can be accommodated. Overall employers want to retain qualified employees and therefore accommodating workers is beneficial to both the employee with CND and the employer.

Interrelation between Neuroendocrine Disturbances and Medical Complications Encountered during Rehabilitation after TBI

Traumatic brain injury is not a discrete event but an unfolding sequence of damage to the central nervous system. Not only the acute phase but also the subacute and chronic period after injury, i.e., during inpatient rehabilitation, is characterized by multiple neurotransmitter alterations, cellular dysfunction, and medical complications causing additional secondary injury. Neuroendocrine disturbances also influence neurological outcome and are easily overlooked as they often present with diffuse symptoms such as fatigue, depression, poor concentration, or a decline in overall cognitive function; these are also typical sequelae of traumatic brain injury. Furthermore, neurological complications such as hydrocephalus, epilepsy, fatigue, disorders of consciousness, paroxysmal sympathetic hyperactivity, or psychiatric-behavioural symptoms may mask and/or complicate the diagnosis of neuroendocrine disturbances, delay appropriate treatment and impede neurorehabilitation. The present review seeks to examine the interrelation between neuroendocrine disturbances with neurological complications frequently encountered after moderate to severe TBI during rehabilitation. Common neuroendocrine disturbances and medical complications and their clinical implications are discussed.

Sleep and fatigue following traumatic brain injury

This article reviews literature relating to sleep disturbance and fatigue after traumatic brain injury. It discusses the nature and prevalence of sleep disturbances associated with traumatic brain injury and the measures used to assess them. Potential causes are discussed, including damage to sleep-wake regulating centers, disruption of circadian timing of sleep, and secondary causes, such as pain, depression, and anxiety. The nature and assessment of fatigue are discussed, followed by a review of evidence regarding causes. Evidence is reviewed of the consequences of sleep disturbance and fatigue. Potential treatments of nonpharmacologic and pharmacologic natures are reviewed.

Actigraphic assessment of sleep disturbances following traumatic brain injury

The current study examined the use of actigraphy in measurement of sleep following traumatic brain injury (TBI). Twenty-one patients with TBI and self-reported sleep and/or fatigue problems and 21 non-injured controls were studied over seven days using actigraphy and sleep diary reports. Although strong associations between diary and actigraphic assessment of sleep duration were observed in both participant groups, agreement between these methods appeared to weaken in patients with TBI. Associations between sleep diary and actigraphic assessments of sleep disturbance, i.e., wake after sleep onset (WASO) and sleep onset latency (SOL) were not apparent in either group, although weaker agreement between methods for WASO was again observed in patients with TBI. Actigraphy may prove useful to supplement self-report measures of sleep following TBI. More work is required to understand the accuracy of these measures in this population.

Randomized Controlled Trial of Light Therapy for Fatigue Following Traumatic Brain Injury

Background. Fatigue is a common, persistent complaint following traumatic brain injury (TBI). Effective treatment is not well established. Objective. The current study aimed to investigate the efficacy of 4 weeks of light therapy for fatigue in patients with TBI. Methods. We undertook a randomized, placebo-controlled study of 4-week, 45 min/morning, home-based treatment with short wavelength (blue) light therapy (λmax = 465 nm, 84.8 µW/cm2, 39.5 lux, 1.74 × 1014 photons/cm2/s) compared with yellow light therapy (λmax = 574 nm, 18.5 µW/cm2, 68 lux, 1.21 × 1012 photons/cm2/s) containing less photons in the short wavelength range and a no treatment control group (n = 10 per group) in patients with TBI who self-reported fatigue and/or sleep disturbance. Assessments of fatigue and secondary outcomes (self-reported daytime sleepiness, depression, sleep quality, and sustained attention) were conducted over 10 weeks at baseline (week −2), midway through and at the end of light therapy (weeks 2 and 4), and 4 weeks following cessation of light therapy (week 8). Results. After controlling age, gender, and baseline depression, treatment with high-intensity blue light therapy resulted in reduced fatigue and daytime sleepiness during the treatment phase, with evidence of a trend toward baseline levels 4 weeks after treatment cessation. These changes were not observed with lower-intensity yellow light therapy or no treatment control conditions. There was also no significant treatment effect observed for self-reported depression or psychomotor vigilance performance. Conclusions. Blue light therapy appears to be effective in alleviating fatigue and daytime sleepiness following TBI and may offer a noninvasive, safe, and nonpharmacological alternative to current treatments.

Changes in sleep patterns following traumatic brain injury: a controlled study

BACKGROUND

Sleep changes are frequently reported following traumatic brain injury (TBI) and have an impact on rehabilitation and quality of life following injury. Potential causes include injury to brain regions associated with sleep regulation, as well as secondary factors, including depression, anxiety, and pain. Understanding the nature and causes of sleep changes following TBI represents a vital step in developing effective treatments.

OBJECTIVE

The study aimed to investigate subjective sleep changes in a community-based sample of individuals with TBI in comparison with noninjured age- and sex-matched controls and to explore the impact of secondary factors (pain, anxiety, depression, employment) on these self-reported sleep changes.

METHODS

A total of 153 participants with mild to severe TBI and 128 noninjured controls completed self-report measures relating to their sleep quality, daytime sleepiness, mood, fatigue, and pain and completed a sleep diary each day for 7 days.

RESULTS

Compared with the noninjured controls, participants with TBI reported significantly poorer sleep quality and higher levels of daytime sleepiness; sleep diaries revealed longer sleep onset latency, poorer sleep efficiency, longer sleep duration, and more frequent daytime napping in the TBI group, as well as earlier bedtimes and greater total sleep duration. Anxiety, depression, and pain were associated with poorer sleep quality. Greater injury severity was also associated with a need for longer sleep time.

CONCLUSION

These findings highlight the importance of assessing and addressing pain, anxiety, and depression as part of the process of treating TBI-related sleep disturbances.

Fatigue and fatigability in neurologic illnesses: proposal for a unified taxonomy

Fatigue is commonly reported in many neurologic illnesses, including multiple sclerosis, Parkinson disease, myasthenia gravis, traumatic brain injury, and stroke. Fatigue contributes substantially to decrements in quality of life and disability in these illnesses. Despite the clear impact of fatigue as a disabling symptom, our understanding of fatigue pathophysiology is limited and current treatment options rarely lead to meaningful improvements in fatigue. Progress continues to be hampered by issues related to terminology and assessment. In this article, we propose a unified taxonomy and a novel assessment approach to addressing distinct aspects of fatigue and fatigability in clinical and research settings. This taxonomy is based on our current knowledge of the pathophysiology and phenomenology of fatigue and fatigability. Application of our approach indicates that the assessment and reporting of fatigue can be clarified and improved by utilizing this taxonomy and creating measures to address distinct aspects of fatigue and fatigability. We review the strengths and weaknesses of several common measures of fatigue and suggest, based on our model, that many research questions may be better addressed by using multiple measures. We also provide examples of how to apply and validate the taxonomy and suggest directions for future research.

Prevalence of sleep disturbances, disorders, and problems following traumatic brain injury: a meta-analysis

BACKGROUND

Sleep is often disrupted following a traumatic brain injury (TBI), which may compromise recovery and quality of life. Prevalence rates vary widely, reflecting differences in the criteria and measures that are used to assess sleep, as well as sample differences. This meta-analysis examined the prevalence of general and specific, and formally and informally diagnosed, sleep disturbances following TBI in order to establish the nature and extent of these sequelae and their potential impact on recovery.

METHODS

Data from 21 studies, which assessed (1) sleep disturbances, regardless of type or severity, (2) diagnosed sleep disorders, and (3) specific sleep problems following TBI, were analyzed and compared to data for the general population.

RESULTS

Overall, 50% of people suffered from some form of sleep disturbance after a TBI and 25-29% had a diagnosed sleep disorder (insomnia, hypersomnia, apnea) - rates that are much higher than those seen in the general population. They were also two to four times more likely to experience problems with sleep maintenance and efficiency, nightmares, excessive sleepiness, early awakenings, and sleep walking.

CONCLUSION

Sleep disturbances are very common after TBI and have the potential to seriously undermine patient rehabilitation, recovery, and outcomes; making it important to routinely screen for such problems in order to assess both treatment needs and their potential impact on recovery and outcome.

The longitudinal course, risk factors, and impact of sleep disturbances in children with traumatic brain injury

This study aimed to examine the prevalence and trajectory of sleep disturbances and their associated risk factors in children up to 24 months following a traumatic brain injury (TBI). In addition, the longitudinal association between sleep disturbances and children's functional outcomes was assessed. This was a prospective study of a cohort of children with TBI and a comparison cohort of children with orthopedic injury (OI). Parental reports of pre-injury sleep disturbances were compared to reports of post-injury changes at 3, 12, and 24 months. Risk factors for sleep disturbances were examined, including severity of TBI, presence of psychosocial problems, and pain. Sleep disturbances were also examined as a predictor of children's functional outcomes in the areas of adaptive behavior skills and activity participation. Both cohorts (children with TBI and OI) displayed increased sleep disturbances after injury. However, children with TBI experienced higher severity and more prolonged duration of sleep disturbances compared to children with OI. Risk factors for disturbed sleep included mild TBI, psychosocial problems, and frequent pain. Sleep disturbances emerged as significant predictors of poorer functional outcomes in children with moderate or severe TBI. Children with TBI experienced persistent sleep disturbances over 24 months. Findings suggest a potential negative impact of disturbed sleep on children's functional outcomes, highlighting the need for further research on sleep in children with TBI.

Traumatic brain injury and its neurobehavioral sequelae

The neurobehavioral sequelae of TBI consist of a spectrum of somatic, neurologic, and psychiatric symptoms. The challenge for clinicians lies in understanding the interface of the various symptoms and how they interrelate with other entities. Specifically, the challenge is differentiating post-TBI-related symptoms from preexisting or de novo psychiatric, neurologic, and/or systemic disorders. A comprehensive evaluation and a multidisciplinary approach to evaluating patients are essential to be able to develop the differential diagnosis needed to design a management plan that maximizes recovery.

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

OBJECTIVE

Define associations between post-traumatic brain injury (TBI) fatigue and abnormalities in neuroendocrine axes, sleep, mood, cognition and physical functioning.

DESIGN

Survey.

SETTING

Large community hospital-based rehabilitation centre.

PARTICIPANTS

Convenience sample of 119 individuals at least 1 year post-TBI.

OUTCOME MEASURES

Multidimensional Assessment of Fatigue (MAF); Fatigue Severity Scale (FSS); neuroendocrine assessments-growth hormone (GH) reserve, thyroid, cortisol and testosterone levels; visual analogue pain rating; Pittsburgh Sleep Quality Index; Beck Depression Inventory-II; Disability Rating Scale; Craig Handicap Assessment and Reporting Technique; Neurobehavioural Functioning Inventory.

RESULTS

Fifty-three per cent reported fatigue on the MAF and one-third on the FSS; 65% were found to have moderate/severe GH deficiency; 64% had adrenal insufficiency (low fasting cortisol); 12% had central hypothyroidism; and 15% of men had testosterone deficiency. Pituitary dysfunction did not correlate with fatigue or other symptoms. Predictors of MAF total scores were female gender, depression, pain and self-assessed memory deficits. Predictors of FSS scores were depression, self-assessed motor deficits and anti-depressant usage.

CONCLUSIONS

Robust correlates of fatigue were gender, depression, pain and memory and motor dysfunction. Investigation of post-TBI fatigue should include screening for depression, pain and sleep disturbance. There was no correlation between pituitary dysfunction and fatigue; however, the relatively high prevalence of hypothyroidism and adrenal dysfunction suggests screening for these hormone deficiencies.

Traumatic brain injury and its neurobehavioral sequelae

The neurobehavioral sequelae (NBS) of traumatic brain injury (TBI) consist of a spectrum of somatic, neurological, and psychiatric symptoms. The challenge for clinicians lies in understanding the interface of the various symptoms and how they interrelate with other entities. Specifically, the challenge is differentiating post-TBI-related symptoms from pre-existing or de novo psychiatric, neurological, and/or systemic disorders. A comprehensive evaluation and a multidisciplinary approach to evaluating patients are essential to be able to develop the differential diagnosis needed to design a management plan that maximizes recovery.

Ventromedial prefrontal cortex modulates fatigue after penetrating traumatic brain injury

BACKGROUND

Fatigue is a common and disabling symptom in neurologic disorders including traumatic penetrating brain injury (PBI). Despite fatigue's prevalence and impact on quality of life, its pathophysiology is not understood. Studies on effort perception in healthy subjects, animal behavioral paradigms, and recent evidence in different clinical populations suggest that ventromedial prefrontal cortex could play a significant role in fatigue pathophysiology in neurologic conditions.

METHODS

We enrolled 97 PBI patients and 37 control subjects drawn from the Vietnam Head Injury Study registry. Fatigue was assessed with a self-report questionnaire and a clinician-rated instrument; lesion location and volume were evaluated on CT scans. PBI patients were divided in 3 groups according to lesion location: a nonfrontal lesion group, a ventromedial prefrontal cortex lesion (vmPFC) group, and a dorso/lateral prefrontal cortex (d/lPFC) group. Fatigue scores were compared among the 3 PBI groups and the healthy controls.

RESULTS

Individuals with vmPFC lesions were significantly more fatigued than individuals with d/lPFC lesions, individuals with nonfrontal lesions, and healthy controls, while these 3 latter groups were equally fatigued. VmPFC volume was correlated with fatigue scores, showing that the larger the lesion volume, the higher the fatigue scores.

CONCLUSIONS

We demonstrated that ventromedial prefrontal cortex lesion (vmPFC) plays a critical role in penetrating brain injury-related fatigue, providing a rationale to link fatigue to different vmPFC functions such as effort and reward perception. The identification of the anatomic and cognitive basis of fatigue can contribute to developing pathophysiology-based treatments for this disabling symptom.

Systematic review of the literature on pain in patients with polytrauma including traumatic brain injury

OBJECTIVE

To review the literature addressing the assessment and management of pain in patients with polytraumatic injuries including traumatic brain injury (TBI) and blast-related headache, and to identify patient, clinician and systems factors associated with pain-related outcomes.

DESIGN

Systematic review.

METHODS

We conducted searches in MEDLINE of literature published from 1950 through July 2008. Due to a limited number of studies using controls or comparators, we included observational and rigorous qualitative studies. We systematically rated the quality of systematic reviews, cohort, and case-control design studies.

RESULTS

One systematic review, 93 observational studies, and one qualitative research study met inclusion criteria. The literature search yielded no published studies that assessed measures of pain intensity or pain-related functional interference among patients with cognitive deficits due to TBI, that compared patients with blast-related headache with patients with other types of headache, or that assessed treatments for blast-related headache pain. Studies on the association between TBI severity and pain reported mixed findings. There was limited evidence that the following factors are associated with pain among TBI patients: severity, location, and multiplicity of injuries; insomnia; fatigue; depression; and post-traumatic stress disorder.

CONCLUSIONS

Very little evidence is currently available to guide pain assessment and treatment approaches in patients with polytrauma. Further research employing systematic observational as well as controlled intervention designs is clearly indicated.

Subjective fatigue, mental effort, and attention deficits after severe traumatic brain injury

OBJECTIVE

Although fatigue is one of the most frequent complaints of individuals with traumatic brain injury (TBI), its mechanisms remain poorly understood. The objective of this study was to assess the relationships between subjective mental fatigue, mental effort, attention deficits, and mood after severe TBI.

METHODS

and participants. A total of 27 patients with subacute/chronic severe TBI were compared with matched controls. Patients first rated their baseline subjective fatigue on the Fatigue Severity Scale (FSS) and on the Visual Analog Scale for Fatigue (VAS-F). Mood was assessed with the Montgomery and Asberg Depression Rating Scale (MADRS). Then, they performed a long-duration selective attention task, separated in 2 parts. Fatigue on the VAS-F was assessed again between the 2 parts and at the end of the attention task. Patients were also asked to rate on the VAS the level of subjective mental effort devoted to the task.

RESULTS

Patients reported a higher baseline fatigue than controls. They performed significantly poorer on the selective attention task. Significant correlations were found in the group with TBI between attention performance, mental effort, and subjective fatigue. Depression did not significantly correlate with fatigue.

DISCUSSION AND CONCLUSIONS

These findings suggest that patients with more severe attention deficits have to produce higher levels of mental effort to manage a complex task, which may increase subjective fatigue, in line with the coping hypothesis.

Baseline predictors of fatigue 1 year after mild head injury

OBJECTIVE

To compare reports of fatigue 12 months after minor trauma by participants with mild head injury (MHI) with those with other injury, and identify injury and baseline predictors of fatigue.

DESIGN

An inception cohort study of participants with MHI and other nonhead injuries recruited from and interviewed at the emergency department (ED), with a follow-up telephone interview at 12 months.

SETTING

Level II community hospital ED.

PARTICIPANTS

Participants (n=58) with MHI and loss of consciousness (LOC) of 30 minutes or less and/or posttraumatic amnesia (PTA) less than 24 hours, 173 with MHI but no PTA/LOC, and 128 with other mild nonhead injuries.

INCLUSION CRITERIA

age 18 years or older, within 24 hours of injury, Glasgow Coma Scale score of 13 or higher, and discharge from the ED.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Medical Outcomes Study 36-Item Short-Form Health Survey Vitality subscale.

RESULTS

Significant predictors of fatigue severity at 12 months were baseline fatigue, having seen a counselor for a mental health issue, medical disability, marital status, and in some stage of litigation. Injury type was not a significant predictor.

CONCLUSIONS

Fatigue severity 12 months after injury is associated with baseline characteristics and not MHI. Clinicians should be cautious about attributing persisting fatigue to MHI without comprehensive consideration of other possible etiologic factors.

Neurobehavioral sequelae of traumatic brain injury

The neurobehavioral sequelae of traumatic brain injury consist of a spectrum of somatic and neuropsychiatric symptoms. The neuropsychiatric symptoms are divided into cognitive and behavioral presentations. In the literature, these neurobehavioral sequelae have been called postconcussive symptoms, postconcussive syndrome, and postconcussive disorder; however, the authors of this review do not use this terminology because the symptoms are not restricted to patients with concussion but instead can be found in all traumatic brain injury patients of all injury severities. The development of neurobehavioral sequelae after traumatic brain injury is a multifactorial process. The patient evaluation requires a multidisciplinary approach in order to delineate physiologic dysfunction and place deficits in the context of the patient's preinjury and postinjury psychiatric status. Consequently, the evaluation of the posttraumatic brain injury patient with neurobehavioral sequelae requires a carefully structured history and physical examination with an emphasis on neurological and psychiatric function. Adjunctive evaluations must be tailored to the patient with neuroimaging, neurophysiological, and neuropsychiatric testing. Maximized outcomes may be achieved by the performance of a careful and detailed assessment that places complaints within the context of the individual.

Assessment of fatigue in adults with disabilities

Fatigue is prevalent and can produce major public health consequences. Assessment of fatigue by the PM&R physician begins with a careful history and physical examination, complemented by pertinent rating scales and laboratory studies. In adults with disabilities, a wide variety of etiologies may lead to fatigue. Educating and providing resources about fatigue to patients can help open the discussion about this highly debilitating symptom.

Patterns of fatigue and its correlates over the first 2 years after traumatic brain injury

This study used a prospective longitudinal design to quantify fatigue and associated factors during the first 2 years after traumatic brain injury (TBI). Fifty-one individuals were assessed at 3 time points: within the first 6, 12, and 18-24 months after TBI. Self-reported fatigue improved during the first year, as did pain, sleep quality, cognitive independence, and involvement in productive activity. Further changes up to 2 years after TBI were not observed. The subset of individuals who reported significant increases in fatigue over the first 2 years demonstrated poorer outcomes in cognition, motor symptoms, and general functioning than those with decreased or stable fatigue.