Examining Moderators of Cognitive Recovery Trajectories After Moderate to Severe Traumatic Brain Injury

Examining the Discrepancy between Subjective Cognitive Complaints and Processing Speed Performance in Military Personnel with Traumatic Brain Injury

OBJECTIVE

To examine correlates of the discrepancy between subjective cognitive complaints and processing speed performance in a sample of military personnel with and without traumatic brain injury (TBI).

METHOD

About 235 U.S. military service members (31 noninjured controls [NIC], 69 injured controls [IC], 70 uncomplicated mild TBI [mTBI], and 65 complicated mild/moderate/severe TBI [sTBI]) prospectively enrolled in a longitudinal TBI study completed neuropsychological testing, performance validity tests, and self-report measures of cognitive complaints and psychological symptoms. Service members were categorized as "Accurate Estimators," "Underestimators," and "Overestimators" based on discrepancies between their subjective cognition and processing speed performance.

RESULTS

The NIC group was less likely to underestimate their cognitive abilities than the mTBI group (p < .05). Discrepancy groups significantly differed in processing speed scores (p < .001), with underestimators demonstrating the best objective cognitive performance. Spearman correlations revealed significant positive correlations between unadjusted discrepancy scores and psychological symptoms in the NIC, IC, and sTBI groups (ps < 0.05) but not the mTBI group (ps > 0.05). In contrast, discrepancy scores adjusted for premorbid intelligence were consistently and positively correlated with psychological symptoms across all injury groups (ps < 0.05).

CONCLUSIONS

Findings suggest that mTBI injuries may increase the likelihood of a patient underestimating their cognitive performance. Further, premorbid cognitive functioning is an important factor in evaluating discrepancies in self-reported cognitive complaints and processing speed performance.

Examining anterior prefrontal cortex resting-state functional connectivity patterns associated with depressive symptoms in chronic moderate-to-severe traumatic brain injury

In chronic moderate-to-severe TBI (msTBI), depression is one of the most common psychiatric consequences. Yet to date, there is limited understanding of its neural underpinnings. This study aimed to better understand this gap by examining seed-to-voxel connectivity in depression, with all voxel-wise associations seeded to the bilateral anterior prefrontal cortices (aPFC). In a secondary analysis of 32 patients with chronic msTBI and 17 age-matched controls acquired from the Toronto Rehab TBI Recovery Study database, the Personality Assessment Inventory Depression scale scores were used to group patients into an msTBI-Dep group (T ≥ 60; n = 13) and an msTBI-Non-Dep group (T < 60; n = 19). Resting-state fMRI scans were analyzed using seed-based connectivity analyses. F-tests, controlling for age and education, were used to assess differences in bilateral aPFC rsFC across the 3 groups. After nonparametric permutation testing, the left aPFC demonstrated significantly increased rsFC with the left (p = 0.041) and right (p = 0.013) fusiform gyri, the right superior temporal lobe (p = 0.032), and the right precentral gyrus (p = 0.042) in the msTBI-Dep group compared to controls. The msTBI-Non-Dep group had no significant rsFC differences with either group. To our knowledge, this study is the first to examine aPFC rsFC in a sample of patients with msTBI exclusively. Our preliminary findings suggest a role for the aPFC in the pathophysiology of depressive symptoms in patients with chronic msTBI. Increased aPFC-sensory/motor rsFC could be associated with vulnerability to depression post-TBI, a hypothesis that warrants further investigation.

Cognitive reserve in the recovery and rehabilitation of stroke and traumatic brain injury: A systematic review

Objective: Cognitive reserve (CR) is the brain's ability to cope with changes related to aging and/or disease. Originally introduced to explain individual differences in the clinical manifestations of dementia, CR has recently emerged as a relevant construct in stroke and traumatic brain injury (TBI). This systematic review aims to investigate whether CR could predict post-stroke and TBI clinical recovery and rehabilitation outcomes, and how different variables used to estimate CR (i.e., proxies) are related to the prognosis and effectiveness of rehabilitation in these clinical populations. Method: A search was made in Pubmed, Embase, and PsycInfo for articles published until 12 January 2023, following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) protocol guidelines. Results: 31 studies were included after completing all screening stages. Overall, results show that a higher CR was associated with a better prognosis and a more effective rehabilitation in most of the clinical aspects considered: cognitive functioning, functional, occupational, and socio-emotional abilities, as well as psychiatric and neurological scales. Conclusions: A higher CR seems to be associated with a more favorable prognosis and a better rehabilitation outcome after stroke and TBI. Results suggest that CR should be taken into account in clinical practice to make more accurate predictions about recovery and effectiveness of rehabilitation. However, some inconsistencies suggest the need for further investigations, possibly using multiple proxies for CR.

Dysregulation of the dopaminergic system secondary to traumatic brain injury: implications for mood and anxiety disorders

Traumatic brain injury (TBI) represents a public health issue with a high mortality rate and severe neurological and psychiatric consequences. Mood and anxiety disorders are some of the most frequently reported. Primary and secondary damage can cause a loss of neurons and glial cells, leading to dysfunction of neuronal circuits, which can induce imbalances in many neurotransmitter systems. Monoaminergic systems, especially the dopaminergic system, are some of the most involved in the pathogenesis of neuropsychiatric and cognitive symptoms after TBI. In this work, we summarize the studies carried out in patients who have suffered TBI and describe alterations in the dopaminergic system, highlighting (1) dysfunction of the dopaminergic neuronal circuits caused by TBI, where modifications are shown in the dopamine transporter (DAT) and alterations in the expression of dopamine receptor 2 (D2R) in brain areas with dopaminergic innervation, thus establishing a hypodopaminergic state and (2) variations in the concentration of dopamine and its metabolites in biological fluids of post-TBI patients, such as elevated dopamine (DA) and alterations in homovanillic acid (HVA). On the other hand, we show a large number of reports of alterations in the dopaminergic system after a TBI in animal models, in which modifications in the levels of DA, DAT, and HVA have been reported, as well as alterations in the expression of tyrosine hydroxylase (TH). We also describe the biological pathways, neuronal circuits, and molecular mechanisms potentially involved in mood and anxiety disorders that occur after TBI and are associated with alterations of the dopaminergic system in clinical studies and animal models. We describe the changes that occur in the clinical picture of post-TBI patients, such as alterations in mood and anxiety associated with DAT activity in the striatum, the relationship between post-TBI major depressive disorders (MDD) with lower availability of the DA receptors D2R and D3R in the caudate and thalamus, as well as a decrease in the volume of the substantia nigra (SN) associated with anxiety symptoms. With these findings, we discuss the possible relationship between the disorders caused by alterations in the dopaminergic system in patients with TBI.

Mental and Physical Health Comorbidities in Traumatic Brain Injury: A Non-TBI Controls Comparison

OBJECTIVE

To examine whether aging with a TBI was associated with a greater burden of health-related comorbidities compared with a non-TBI control cohort and examine the associations between comorbidity burden, emotional outcomes, and health-related quality of life (HRQoL) after TBI across ages.

DESIGN

Cross-sectional.

SETTING

Research center or telephone.

PARTICIPANTS

The study included 559 participants (NTBI=291, NControls=268). Participants with TBI were recruited during inpatient rehabilitation and had sustained a moderate-severe TBI 1-33 years previously. Non-TBI controls were a convenience sample recruited through advertisements in the community.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The number of cardiovascular, general physical health, and mental health comorbidities was compared between cohorts and age strata using Poisson regression. The relationships between comorbidities, age, emotional outcomes (Generalized Anxiety Disorder Scale-7, Patient Health Questionnaire-9), and HRQoL (PROMIS Global Health Measure) were examined with linear regression. Distinct subgroups of comorbidities were identified using latent class analysis. Associations between comorbidity classes with demographic and outcome variables were evaluated using multinomial logistic and linear regressions, respectively.

RESULTS

TBI participants had a significantly higher comorbidity burden than controls, primarily driven by elevated rates of mental health disorders (RR=2.71, 95% confidence interval [1.37, 5.35]). Cardiovascular and physical health comorbidities were not elevated in the TBI group compared with controls. Both cohorts had 3 similar comorbidity subgroups, suggesting consistent patterns of co-occurring health conditions regardless of TBI exposure. Physical and mental health comorbidities were associated with elevated depression and anxiety symptoms and diminished HRQoL after TBI compared with controls.

CONCLUSION

TBI was associated with greater mental, but not physical, health comorbidities in the decades after injury. However, physical and mental health comorbidities significantly affected emotional and HRQoL status after TBI, underscoring a greater need for long-term support for individuals with TBI coping with both physical and mental health comorbidities.

The impact of age on outcome 2 years after traumatic brain injury: Case control study

BACKGROUND

Age is associated with outcome after traumatic brain injury (TBI). However, there are mixed findings across outcome domains and most studies lack controls.

OBJECTIVES

This cross-sectional study examined the association between age group (15-24 years, 25-34 years, 35-44 years, 45-54 years, 55-64 years, and 65 years or more) and outcomes 2 years after TBI in independence in daily activities, driving, public transportation use, employment, leisure activities, social integration, relationships and emotional functioning, relative to healthy controls. It was hypothesized that older individuals with TBI would have significantly poorer outcomes than controls in all domains except anxiety and depression, for which it was expected they would show better outcomes. Global functional outcome (measured using the Glasgow Outcome Scale-Extended) was also examined, and we hypothesized that older adults would have poorer outcomes than younger adults.

METHODS

Participants were 1897 individuals with TBI (mean, SD age 36.7, 17.7 years) who completed measures 2 years post-injury and 110 healthy controls (age 38.3, 17.5 years).

RESULTS

Compared to controls, individuals with TBI were less independent in most activities of daily living, participated less in leisure activities and employment, and were more socially isolated, anxious and depressed (p < 0.001). Those who were older in age were disproportionately less likely to be independent in light domestic activities, shopping and driving; and participated less in occupational activities relative to controls. Functional outcome was significantly higher in the youngest age group than in all older age groups (p < 0.001), but the younger groups were more likely to report being socially isolated (p < 0.001), depressed (p = 0.005) and anxious (p = 0.02), and less likely to be married or in a relationship (p < 0.001).

CONCLUSION

A greater focus is needed on addressing psychosocial issues in younger individuals with TBI, whereas those who are older may require more intensive therapy to maximise independence in activities of daily living and return to employment.

The contribution of the meningeal immune interface to neuroinflammation in traumatic brain injury

Traumatic brain injury (TBI) is a major cause of disability and mortality worldwide, particularly among the elderly, yet our mechanistic understanding of what renders the post-traumatic brain vulnerable to poor outcomes, and susceptible to neurological disease, is incomplete. It is well established that dysregulated and sustained immune responses elicit negative consequences after TBI; however, our understanding of the neuroimmune interface that facilitates crosstalk between central and peripheral immune reservoirs is in its infancy. The meninges serve as the interface between the brain and the immune system, facilitating important bi-directional roles in both healthy and disease settings. It has been previously shown that disruption of this system exacerbates neuroinflammation in age-related neurodegenerative disorders such as Alzheimer's disease; however, we have an incomplete understanding of how the meningeal compartment influences immune responses after TBI. In this manuscript, we will offer a detailed overview of the holistic nature of neuroinflammatory responses in TBI, including hallmark features observed across clinical and animal models. We will highlight the structure and function of the meningeal lymphatic system, including its role in immuno-surveillance and immune responses within the meninges and the brain. We will provide a comprehensive update on our current knowledge of meningeal-derived responses across the spectrum of TBI, and identify new avenues for neuroimmune modulation within the neurotrauma field.

Moderate-Severe TBI as a Progressive Disorder: Patterns and Predictors of Cognitive Declines in the Chronic Stages of Injury

BACKGROUND

Moderate-severe traumatic brain injury (TBI) has been associated with progressive cognitive decline in the chronic injury stages in a small number of studies.

OBJECTIVE

This study aimed to (i) replicate our previous findings of decline from 1 to 3+ years post-injury in a larger, non-overlapping sample and (ii) extend these findings by examining the proportion of decliners in 2 earlier time windows, and by investigating novel predictors of decline.

METHODS

N = 48 patients with moderate-severe TBI underwent neuropsychological assessment at 2, 5, 12 months, and 30+ months post-injury. We employed the Reliable Change Index (RCI) to evaluate decline, stability and improvement across time and logistic regression to identify predictors of decline (demographic/cognitive reserve; injury-related).

RESULTS

The proportions of patients showing decline were: 12.5% (2-5 months post-injury), 17% (5-12 months post-injury), and 27% (12-30+ months post-injury). Measures of verbal retrieval were most sensitive to decline. Of the predictors, only left progressive hippocampal volume loss from 5 to 12 months post-injury significantly predicted cognitive decline from 12 to 30+ months post-injury.

CONCLUSIONS

Identical to our previous study, 27% of patients declined from 12 to 30+ months post-injury. Additionally, we found that the further from injury, the greater the proportion of patients declining. Importantly, earlier progressive hippocampal volume loss predicted later cognitive decline. Taken together, the findings highlight the need for ongoing research and treatment that target these deleterious mechanisms affecting patients in the chronic stages of moderate-severe TBI.

Predictors and Functional Outcomes Associated With Longitudinal Trajectories of Anxiety and Depression from 2 to ≥36 Months After Moderate to Severe Traumatic Brain Injury

This study investigated longitudinal trajectories of anxiety and depressive symptoms following moderate-severe traumatic brain injury (TBI), predictors of the trajectories, and associations with 1-year return to productivity. One hundred forty-eight patients with moderate-severe TBI were assessed at 2, 5, 12, and ≥36 months post-injury on the Beck Anxiety Inventory and the Beck Depression Inventory. Clinical interviews obtained information about demographics, injury characteristics, and 1-year return to productivity. Latent growth mixture modeling identified trajectories of anxiety and depression across time. The three-step method identified predictors of trajectories, and χ2 analyses determined associations between trajectories and 1-year return to productivity. Analyses revealed that four-class models of anxiety and depression best fit the data. Most individuals had stable minimal (67%) or low (18%) levels of anxiety over time. Two other subsets of individuals were classified by anxiety that worsened rapidly (7%) or improved in the 1st year but worsened by 3 years post-injury (9%). Similarly for the depression trajectories, most individuals had stable minimal (70%) or low (10%) levels of depression over time. Others had depression that worsened rapidly (12%) or was delayed, with onset 1-year post-injury (8%). Predictors of worsening anxiety and depression included younger age, less education, and male gender. Those with worsening anxiety or depression were less likely to return to productivity by 1-year post-injury. There is a significant burden of anxiety (15%) and depression (20%) in the 3 years after moderate-severe TBI. Future research targeting at-risk patients may help to improve quality of life and functional recovery.

Traumatic brain injury induces an adaptive immune response in the meningeal transcriptome that is amplified by aging

Traumatic Brain Injury (TBI) is a major cause of disability and mortality, particularly among the elderly, yet our mechanistic understanding of how age renders the post-traumatic brain vulnerable to poor clinical outcomes and susceptible to neurological disease remains poorly understood. It is well established that dysregulated and sustained immune responses contribute to negative outcomes after TBI, however our understanding of the interactions between central and peripheral immune reservoirs is still unclear. The meninges serve as the interface between the brain and the immune system, facilitating important bi-directional roles in healthy and disease settings. It has been previously shown that disruption of this system exacerbates inflammation in age related neurodegenerative disorders such as Alzheimer's disease, however we have an incomplete understanding of how the meningeal compartment influences immune responses after TBI. Here, we examine the meningeal tissue and its response to brain injury in young (3-months) and aged (18-months) mice. Utilizing a bioinformatic approach, high-throughput RNA sequencing demonstrates alterations in the meningeal transcriptome at sub-acute (7-days) and chronic (1 month) timepoints after injury. We find that age alone chronically exacerbates immunoglobulin production and B cell responses. After TBI, adaptive immune response genes are up-regulated in a temporal manner, with genes involved in T cell responses elevated sub-acutely, followed by increases in B cell related genes at chronic time points after injury. Pro-inflammatory cytokines are also implicated as contributing to the immune response in the meninges, with ingenuity pathway analysis identifying interferons as master regulators in aged mice compared to young mice following TBI. Collectively these data demonstrate the temporal series of meningeal specific signatures, providing insights into how age leads to worse neuroinflammatory outcomes in TBI.

Cognitive reserve and individual differences in brain tumour patients

The aim of the paper is to determine the effects of the cognitive reserve on brain tumour patients' cognitive functions and, specifically, if cognitive reserve helps patients cope with the negative effects of brain tumours on their cognitive functions. We retrospectively studied a large sample of around 700 patients, diagnosed with a brain tumour. Each received an MRI brain examination and performed a battery of tests measuring their cognitive abilities before they underwent neurosurgery. To account for the complexity of cognitive reserve, we construct our cognitive reserve proxy by combining three predictors of patients' cognitive performance, namely, patients' education, occupation, and the environment where they live. Our statistical analysis controls for the type, side, site, and size of the lesion, for fluid intelligence quotient, and for age and gender, in order to tease out the effect of cognitive reserve on each of these tests. Clinical neurological variables have the expected effects on cognitive functions. We find a robust positive effect of cognitive reserve on patients' cognitive performance. Moreover, we find that cognitive reserve modulates the effects of the volume of the lesion: the additional negative impact of an increase in the tumour size on patients' performance is less severe for patients with higher cognitive reserve. We also find substantial differences in these effects depending on the cerebral hemisphere where the lesion occurred and on the cognitive function considered. For several of these functions, the positive effect of cognitive reserve is stronger for patients with lesions in the left hemisphere than for patients whose lesions are in the right hemisphere. The development of prevention strategies and personalized rehabilitation interventions will benefit from our contribution to understanding the role of cognitive reserve, in addition to that of neurological variables, as one of the factors determining the patients' individual differences in cognitive performance caused by brain tumours.

Group-Based Patterns of Life Satisfaction and Functional Independence over the 10 Years after Traumatic Brain Injury in Older Adults: A Model Systems Study

BACKGROUND

Older adults who sustain a traumatic brain injury (TBI) have been shown to have reduced functional independence and life satisfaction relative to younger individuals with TBI. The purpose of this study was to examine the covarying patterns of functional independence and life satisfaction over the 10 years after TBI in adults who were 60 years of age or older upon injury.

METHOD

Participants were 1841 individuals aged 60 or older at the time of TBI, were enrolled in the longitudinal TBI Model Systems database, and had Functional Independence Measure and Satisfaction with Life Scale scores during at least one time point at 1, 2, 5, and 10 years after TBI.

RESULTS

A k-means cluster analysis identified four distinct group-based longitudinal patterns of these two variables. Three cluster groups suggested that functional independence and life satisfaction generally traveled together over time, with one group showing relatively high functional independence and life satisfaction over time (Cluster 2), one group showing relatively moderate functional independence and life satisfaction (Cluster 4), and one group showing relatively low functional independence and life satisfaction (Cluster 1). Cluster 3 had relatively high functional independence over time but, nonetheless, relatively low life satisfaction; they were also the youngest group upon injury. Participants in Cluster 2 generally had the highest number of weeks of paid competitive employment but lower percentages of underrepresented racial/ethnic minority participants, particularly Black and Hispanic individuals. Women were more likely to be in the cluster with the lowest life satisfaction and functional independence (Cluster 1).

CONCLUSION

Functional independence and life satisfaction generally accompany one another over time in older adults, although this does not always occur, as life satisfaction can still be low in a subgroup of older individuals after TBI with higher functioning. These findings contribute to a better understanding of post-TBI recovery patterns in older adults over time that may inform treatment considerations to improve age-related discrepancies in rehabilitation outcomes.

Predictors of cognitive gains during inpatient rehabilitation for older adults with traumatic brain injury

INTRODUCTION

Traumatic brain injury (TBI) among older adults is increasing and can affect cognition. To effectively meet the rehabilitation needs of older adults, a clearer picture is needed of patient-, clinical-, and facility-level characteristics that affect cognitive recovery during inpatient rehabilitation facility (IRF) stays.

OBJECTIVE

To identify patient, clinical, and facility factors associated with cognitive recovery among older adults with TBI who received IRF care.

DESIGN

Secondary data analysis.

SETTING

Uniform Data System for Medical Rehabilitation-participating IRFs in the United States.

PATIENTS

Patients were 65 to 99 years of age at IRF admission for TBI. Participants received IRF care between 2002 and 2018 (N = 137,583); 56.3% were male; 84.2% were white; mean age was 78.7 years.

MAIN OUTCOME MEASURE

Change in Functional Independence Measure Cognitive Score (FIM-Cognitive) from IRF admission to discharge, categorized as favorable (FIM-cognitive score gains ≥3 points) or poor (FIM-cognitive score gains <3 points) cognitive outcomes.

INTERVENTIONS

Not applicable.

RESULTS

Patients had greater odds of favorable cognitive recovery if they were female (adjusted odds ratio [aOR] 1.05, 95% confidence interval [CI] 1.05-1.08), had higher motor functioning at IRF admission (aOR 1.03, 95% CI 1.03-1.04), longer length of stay (aOR 1.07, 95% CI 1.06-1.07), or received care at a freestanding IRF (vs. hospital rehab unit) (aOR 1.57, 95% CI 1.52-1.61). Patients who were older (aOR 0.99, 95% CI 0.98-0.99), Black (aOR 0.79, 95% CI 0.75-0.83), Hispanic or Latino (aOR 0.97, 95% CI 0.91-1.02), or were part of another racial or ethnic group (aOR 0.85, 95% CI 0.81-0.90) (vs. White), had high-cost comorbid conditions (aOR 0.71, 95% CI 0.65-0.76), or who had higher cognitive functioning at IRF admission (aOR 0.90, 95% CI 0.90-0.91) had lower odds of favorable cognitive recovery.

CONCLUSIONS

Patient (age, sex, race, ethnicity), clinical (level of functioning at IRF admission, length of stay) and facility (e.g., freestanding IRF) factors contributed to the cognitive recoveries of older adults during IRF stays.

The burden of geriatric traumatic brain injury on trauma systems: Analysis of 348,800 Medicare inpatient claims

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of death and disability in older adults. The aim of this study was to characterize the burden of TBI in older adults by describing demographics, care location, diagnoses, outcomes, and payments in this high-risk group.

METHODS

Using 2016-2019 Centers for Medicare & Medicaid Services (CMS) Inpatient Standard Analytical Files (IPSAF), patients >65 years with TBI (>1 injury ICD-10 starting with "S06") were selected. Trauma center levels were linked to the IPSAF file via American Hospital Association Hospital Provider ID and fuzzy-string matching. Patient variables were compared across trauma center levels.

RESULTS

Three hundred forty-eight thousand eight hundred inpatients (50.4% female; 87.1% white) from 2963 US hospitals were included. Level I/II trauma centers treated 66.9% of patients; non-trauma centers treated 21.5%. Overall inter-facility transfer rate was 19.2%; in Level I/II trauma centers transfers-in represented 23.3% of admissions. Significant TBI (Head AIS ≥3) was present in 70.0%. Most frequent diagnoses were subdural hemorrhage (56.6%) and subarachnoid hemorrhage (30.6%). Neurosurgical operations were performed in 10.9% of patients and operative rates were similar regardless of center level. Total unadjusted mortality for the sample was 13.9%, with a mortality of 8.1% for those who expired in-hospital, and an additional 5.8% for those discharged to hospice. Medicare payments totaled $4.91B, with the majority (73.4%) going to Level I/II trauma centers.

CONCLUSIONS

This study fills a gap in TBI research by demonstrating that although the majority of older adult TBI patients in the United States receive care at Level I/II trauma centers, a substantial percentage are managed at other facilities, despite 1 in 10 requiring neurosurgical operation regardless of level of trauma center. This analysis provides preliminary data on the function of regionalized trauma care for older adult TBI care. Future studies assessing the efficacy of early care guidelines in this population are warranted.

Relationships between predisposing, precipitating, and perpetuating factors and executive functioning following mild traumatic brain injury

INTRODUCTION

The aim of this study was to determine the sociodemographic and MTBI-related variables associated with executive functioning (EF).

METHODS

Based on the theoretical model of Hou and colleagues, data on predisposing (age, education, premorbid IQ), precipitating (post-traumatic amnesia, loss of consciousness, presence of frontal lesions, post-accident time to evaluation) and perpetuating (anxious and depressive affects and post-concussive symptoms) factors were retrospectively collected from the medical records of 172 patients with MTBI. EF data based on the 3 processes included in Miyake's prediction model (2000) (updating, cognitive flexibility and inhibition) were collected using respectively the Digit span task of the Weschler - 4^th edition, the Trails A and B as well as the initiation time on the Tower of London- Drexel University.

RESULTS

Updating was significantly associated with education, premorbid IQ, age, anxiety, and depressive affect. Inhibition was associated with education and age. No variable was associated with cognitive flexibility.

CONCLUSIONS

Following a MTBI, clinicians should consider that level of education and pre-morbid IQ may "predispose" patients to higher EF performances. They should also measure level of anxiety and depressive affect knowing that these may "perpetuate" some EF impairments (specifically the updating process).

Effect of computerized cognitive rehabilitation in comparison between young and old age after traumatic brain injury

INTRODUCTION

Cognitive dysfunction reduces patients' quality of life and social participation with traumatic brain injury (TBI). Computerized cognitive rehabilitation is increasingly being used for cognitive therapy in TBI patients. The purpose of this study was to investigate the influence of age on the effect of computerized cognitive rehabilitation in cognitive dysfunction after TBI.

MATERIAL AND METHODS

A total of 34 patients with cognitive dysfunction after TBI were enrolled. Participants performed 30 sessions of computerized cognitive rehabilitation (Comcog) for 6 weeks. A cognitive evaluation was performed before and after treatment with Mini-Mental State Examination (MMSE) and Computerized Neurophyschologic Test (CNT).

RESULTS

There were no cognitive tests that differed between the young group and the old group at baseline. However, after computerized cognitive rehabilitation, the young group showed significant improvement compared to the old group in verbal memory, visual memory, attention, and visuo-motor coordination tests. The young group showed improvement in MMSE, verbal and visual memory, and visuo-motor coordination tests after computerized cognitive rehabilitation. In contrast, the old group showed significant improvement only in MMSE and visual learning test, one of the visual memory tests.

CONCLUSION

Our findings demonstrate that age may be an important factor related to the effect of computer cognitive rehabilitation on cognitive dysfunction after TBI. Methodologically more ordered studies with larger sample sizes are needed in the future.

The influence of cognitive reserve in the protection of the cognitive status after an acquired brain injury: A systematic review

BACKGROUND

Cognitive Reserve (CR) hypothesis was introduced to account for the variability in cognitive performance of patients with similar degrees of brain injury or pathology. The individual variability of CR is modulated by the interaction of innate capacities and exposures throughout life, which can act as protectors against neuropathology's clinical effects. Individuals with higher CR appear to have better cognitive performance after a brain injury. The present review aimed to identify and map the scientific evidence available in literature regarding CR's influence in protecting the cognitive status after an Acquired Brain Injury (ABI).

METHOD

A systematic review was performed for published studies until October 2020 in PubMed, Scopus, and CINAHL electronic databases. Studies regarding CR's influence in protecting the cognitive status after an ABI were included in this review. The Newcastle-Ottawa Scale was used to assess risk of bias in the included studies. This systematic review was recorded in the International Prospective Register of Systematic Reviews (PROSPERO) under the number CRD42021236594.

RESULTS

Twenty-one studies published between 2003 and 2020 were selected and analyzed. The literature analysis showed that CR has a positive effect on cognitive status after an ABI. Various proxies were used to estimate CR, including estimated premorbid IQ, education, occupation attainment, socioeconomic status, leisure activities, bilingualism, and social integration. CR proxies constitute a set of variables that may have a significant influence on cognitive status. Higher CR levels were associated with lower cognitive impairment after an ABI.

CONCLUSIONS

Although more research is necessary for a complete understanding of CR's impact on cognition, the synthesis of these studies confirmed that there is evidence on the beneficial impact of CR on cognitive status after an ABI. These findings support CR's cognitive status role following an ABI and may provide additional information for prognosis and rehabilitation plans.

Patterns of change in cortical morphometry following traumatic brain injury in adults

Progressive cortical volumetric loss following moderate–severe traumatic brain injury (TBI) has been observed; however, regionally specific changes in the structural determinants of cortical volume, namely, cortical thickness (CT) and cortical surface area (CSA), are unknown and may inform the patterns and neural substrates of neurodegeneration and plasticity following injury. We aimed to (a) assess differences in CT and CSA between TBI participants and controls in the early chronic stage post‐injury, (b) describe longitudinal changes in cortical morphometry following TBI, and (c) examine how regional changes in CT and CSA are associated. We acquired magnetic resonance images for 67 participants with TBI at up to 4 time‐points spanning 5 months to 7 years post‐injury, and 18 controls at 2 time‐points. In the early chronic stage, TBI participants displayed thinner cortices than controls, predominantly in frontal regions, but no CSA differences. Throughout the chronic period, TBI participants showed widespread CT reductions in posterior cingulate/precuneus regions and moderate CT increase in frontal regions. Additionally, CSA showed a significant decrease in the orbitofrontal cortex and circumscribed increase in posterior regions. No changes were identified in controls. Relationships between regional cortical changes in the same morphological measure revealed coordinated patterns within participants, whereas correlations between regions with CT and CSA change yielded bi‐directional relationships. This suggests that these measures may be differentially affected by neurodegenerative mechanisms such as transneuronal degeneration following TBI and that degeneration may be localized to the depths of cortical sulci. These findings emphasize the importance of dissecting morphometric contributions to cortical volume change.

Factors Affecting Outcomes in Geriatric Traumatic Subdural Hematoma in a Neurosurgical Intensive Care Unit

BACKGROUND AND OBJECTIVE

Geriatric patients (age ≥65 years) who sustain a traumatic brain injury have an increased risk of poor outcomes and higher mortality compared with younger cohorts. We aimed to evaluate the risk factors for discharge outcomes in a geriatric traumatic subdural hematoma population, stratified by age and pretraumatic medical comorbidities. This was a single-center retrospective cohort study of geriatric patients (N = 207).

METHODS

Patient charts were evaluated for factors including patient characteristics, comorbidities, injury-related and seizure-related factors, neurosurgical intervention, and patient disposition on discharge.

RESULTS

Bivariate and multivariate analyses showed that age was nonpredictive of patient outcomes. Underlying vasculopathic comorbidities were the primary determinant of posttraumatic seizure, surgical, and discharge outcomes. Multifactor analysis showed that patients who went on to develop status epilepticus (n = 11) had a higher frequency of vasculopathic comorbidities with strong predictive power in poor patient outcomes.

CONCLUSIONS

Our findings suggest a need to establish unique prognostic risk factors based on patient outcomes that guide medical and surgical treatment in geriatric patients.

A Longitudinal, Prospective Study to Evaluate the Effects of Treatment on the Inhibitory Control Function After Transsphenoidal Surgery for Pituitary Adenomas

OBJECTIVES

Injured cognitive abilities have been reported in patients with pituitary adenoma. However, to date, few researchers have directly investigated the electrophysiological study of inhibitory control function of pituitary patients both pre- and postsurgery. Thus, this study aimed to identify the factors affecting the inhibitory control function of pituitary patients.

METHODS

Thirty presurgery pituitary patients were recruited and 26 patients of them completed the postsurgery follow-up. Thirty healthy people were recruited for control group. Visual Go/Nogo tasks were carried out by the patients and controls to assess the inhibitory control function before surgery and 6 months after the surgery, respectively. The function of inhibitory control was analyzed with the components of N2 and P3.

RESULTS

Across 3 groups, Nogo stimuli evoked larger frontal-central N2nogo and P3nogo than Go stimuli did. Furthermore, N2d of presurgery patients (-1.14 μV) and postsurgery patients(-0.61 μV) were significantly decreased compared with that of control group (-3.09 μV), F(2, 83) = 13.92, P < .01, whereas no difference was detected between pre- and postsurgery groups. There was no remarkable difference in the amplitude of P3d among the 3 groups, F(2, 83) = 0.19, P > .05. With regard to the amplitude of P3 for Go condition, The P3 amplitude of healthy group (4.38 μV) was larger than both pre- and postsurgery (1.00 μV and 3.01 μV). With regard to the amplitude of P3 for Nogo condition, The P3 amplitude of healthy group (5.25 μV) was larger than both pre- and postsurgery groups (2.35 μV and 4.18 μV).

CONCLUSIONS

These results indicated that presurgery patients showed the dysfunction of inhibition, due to the nerve tissue damage or brain structure alteration caused by the presurgery physical pressure from tumor and abnormal hormone levels. Postsurgery patients showed a tendency toward recovery, but there was no obvious improvement in the inhibitory control function after successful treatments.

New insights into neural networks of error monitoring and clinical implications: a systematic review of ERP studies in neurological diseases

Error monitoring allows for the efficient performance of goal-directed behaviors and successful learning. Furthermore, error monitoring as a metacognitive ability may play a crucial role for neuropsychological interventions, such as rehabilitation. In the past decades, research has suggested two electrophysiological markers for error monitoring: the error-related negativity (ERN) and the error positivity (Pe), thought to reflect, respectively, error detection and error awareness. Studies on several neurological diseases have investigated the alteration of the ERN and the Pe, but these findings have not been summarized. Accordingly, a systematic review was conducted to understand what neurological conditions present alterations of error monitoring event-related potentials and their relation with clinical measures. Overall, ERN tended to be reduced in most neurological conditions while results related to Pe integrity are less clear. ERN and Pe were found to be associated with several measures of clinical severity. Additionally, we explored the contribution of different brain structures to neural networks underlying error monitoring, further elaborating on the domain-specificity of error processing and clinical implications of findings. In conclusion, electrophysiological signatures of error monitoring could be reliable measures of neurological dysfunction and a robust tool in neuropsychological rehabilitation.

Cognitive Reserve in Individuals Aging With Traumatic Brain Injury: Independent and Interactive Effects on Cognitive Functioning

OBJECTIVE

To examine the influence of 2 temporal factors-age and injury chronicity-on the relationship between cognitive reserve (CR) and cognitive functioning in older adults with chronic traumatic brain injury (TBI).

SETTING

Outpatient research laboratory.

PARTICIPANTS

Adults, 50 years or older, with a 1- to 45-year history of moderate or severe TBI (N = 108).

DESIGN

Cross-sectional observational study.

MAIN MEASURES

CR was estimated using demographically corrected performance on a word-reading test (an approximation of premorbid IQ). Injury chronicity was operationalized as number of years since the date of injury. Composite cognitive scores were computed from performances on neuropsychological tests of processing speed, executive functioning, and memory.

RESULTS

CR was positively and significantly related to all cognitive performances independent of age, injury chronicity, and injury severity. Greater injury chronicity significantly attenuated the effect of CR on processing speed such that individuals more distal from their injury date evidenced a weaker positive relationship between CR and performance.

CONCLUSION

Temporal factors may modify associations between CR and cognition. Findings suggest that the protective effects of CR are temporally delimited, potentially contending with declines in brain reserve. The prognostic value of traditional outcome determinants should be considered in the context of injury chronicity.

The Association Between Brain Reserve, Cognitive Reserve, and Neuropsychological and Functional Outcomes in Males With Chronic Moderate-to-Severe Traumatic Brain Injury

Purpose Moderate-to-severe traumatic brain injury (TBI) leads to significant neural and cognitive impairment, affecting functional outcome. This study investigated the chronic effects of moderate-to-severe TBI on brain reserve (BR), cognitive reserve (CR), and neuropsychological and functional outcome. Method The group with TBI consisted of 41 male participants with a primary diagnosis of moderate-to-severe closed head injury (time since injury [TSI], M = 6.12 years, range: 1-23, SD = 5.99, Mdn = 4). TBI survivors were compared to 24 neurotypical male participants, matched on age and education. Magnetic resonance imaging T1 anatomical images were used to calculate gray and white matter and cerebrospinal fluid volume. BR was calculated using the ventricle-to-brain ratio. CR was assessed using two hold measures: the Peabody Picture Vocabulary Test and the Pseudowords task. Functional outcome was measured using the Glasgow Outcome Scale-Extended. Results Neuropsychological performance of TBI survivors was significantly lower than their neurotypical controls, as measured by theoretically driven composites of verbal and visual memory, executive functions, attention, and CR. They presented greater ventricle-to-brain ratio volume, compared to noninjured controls, with higher scores indicating lower BR levels. Both BR and TSI were significantly associated with CR. Also, a median-split analysis revealed a TSI effect on CR. Significant associations were evident between the Glasgow Outcome Scale-Extended and the BR and CR measures. Conclusions Lingering neuropsychological deficits in chronic TBI support the role of BR and CR in functional outcome. Furthermore, TSI interferes with CR supporting the notion that TBI sets off a chronic neurodegenerative and progressive course that interferes with semantic knowledge. Supplemental Material https://doi.org/10.23641/asha.14049923.

Does cognitive decline occur decades after moderate to severe traumatic brain injury? A prospective controlled study

This prospective controlled study examined long-term trajectories of neuropsychological performance in individuals with traumatic brain injury (TBI) compared to healthy controls, and the impact of IQ, age at injury, time since injury, and injury severity on change over time. Fifty-three individuals with moderate to severe TBI (60.37% male; M = 59.77 yrs, SD = 14.03), and 26 controls (46.15% male; M = 63.96 yrs, SD = 14.42) were studied prospectively (M = 12.72 yrs between assessments). Participants completed measures of premorbid IQ (Weschler Test of Adult Reading), processing speed (Digit Symbol Coding Test), working memory (Digit Span Backwards), memory (Rey Auditory Verbal Learning Test) and executive function (Trail Making Test Part B; Hayling Errors), at a mean of 10.62 yrs (Initial) and 23.91 yrs (Follow-Up) post injury. Individuals with TBI did not show a significantly greater decline in neuropsychological performance over time compared with demographically similar controls. There was no association between change over time with IQ, time since injury or injury severity. Being older at injury had a greater adverse impact on executive function at follow-up. In this small sample, a single moderate to severe TBI was not associated with ongoing cognitive decline up to three decades post injury. Changes in cognitive function were similar between the groups and likely reflect healthy aging.

Early chronic systemic inflammation and associations with cognitive performance after moderate to severe TBI

BACKGROUND

Cognitive dysfunction adversely effects multiple functional outcomes and social roles after TBI. We hypothesize that chronic systemic inflammation exacerbates cognitive deficits post-injury and diminishes functional cognition and quality of life (QOL). Yet few studies have examined relationships between inflammation and cognition after TBI. Associations between early chronic serum inflammatory biomarker levels, cognitive outcomes, and QOL 6-months and 12-months after moderate-to-severe TBI were identified using unweighted (uILS) and weighted (wILS) inflammatory load score (ILS) formation.

METHODS

Adults with moderate-to-severe TBI (n ​= ​157) completed neuropsychological testing, the Functional Impairment Measure Cognitive Subscale (FIM-Cog) and self-reported Percent Back to Normal scale 6 months (n ​= ​139) and 12 months (n ​= ​136) post-injury. Serial serum samples were collected 1-3 months post-TBI. Cognitive composite scores were created as equally weighted means of T-scores derived from a multidimensional neuropsychological test battery. Median inflammatory marker levels associated with 6-month and 12-month cognitive composite T-scores (p ​< ​0.10) were selected for ILS formation. Markers were quartiled, and quartile ranks were summed to generate an uILS. Marker-specific β-weights were derived using penalized ridge regression, multiplied by standardized marker levels, and summed to generate a wILS. ILS associations with cognitive composite scores were assessed using multivariable linear regression. Structural equation models assessed ILS influences on functional cognition and QOL using 12-month FIM-Cog and Percent Back to Normal scales.

RESULTS

ILS component markers included: IL-1β, TNF-α, sIL-4R, sIL-6R, RANTES, and MIP-1β. Increased sIL-4R levels were positively associated with overall cognitive composite T-scores in bivariate analyses, while remaining ILS markers were negatively associated with cognition. Multivariable receiver operator curves (ROC) showed uILS added 14.98% and 31.93% relative improvement in variance captured compared to the covariates only base model (age, sex, education, Glasgow Coma Scale score) when predicting cognitive composite scores at 6 and 12 months, respectively; wILS added 33.99% and 36.87% relative improvement in variance captured. Cognitive composite mediated wILS associations with FIM-Cog scores at 12 months, and both cognitive composite and FIM-Cog scores mediated wILS associations with QOL.

CONCLUSIONS

Early chronic inflammatory burden is associated with cognitive performance post-TBI. wILS explains greater variance in cognitive composite T-scores than uILS. Linking inflammatory burden associated with cognitive deficits to functional outcome post-TBI demonstrates the potential impact of immunotherapy interventions aimed at improving cognitive recovery post-TBI.

Beneficial effects of a multidomain cognitive rehabilitation program for traumatic brain injury-associated diffuse axonal injury: a case report

Background

Neuropsychological rehabilitation is a crucial component of medical care for patients with diffuse axonal injury (DAI). However, current cognitive intervention programs directed to favor the training of specific domains individually have shown controversial results. Here, we evaluated the effectiveness of a neuropsychological rehabilitation program directed to favor training of attention, memory, visuospatial abilities, and executive functioning together in a patient with severe traumatic brain injury (TBI)-associated DAI.

Case presentation

A 26-year-old Hispanic woman with a recent history of a severe TBI attended our center complaining of memory problems, dysarthria, and difficulty in planning. A comprehensive cognitive assessment revealed dysfunction in sustained, selective, and divided attention, alterations in memory, planning, and organization of executive behavior, as well as impairment of visuospatial cognitive functions. The patient underwent a 24-week neuropsychological rehabilitation program directed to favor attention, memory, visuospatial abilities, and executive functioning together. After the cognitive intervention, we observed a better patient's performance in tasks requiring sustained, selective, and divided attention, improvement of encoding and retrieval memory problems, use of spatial relationships, planning, and organization of behavior skills. We also observed generalization effects on other domains, such as learning, mental flexibility, inhibition functions, and language.

Conclusions

In conclusion, our results suggest that neuropsychological rehabilitation programs favoring multiple domains together are useful in reestablishing cognitive deficits in patients with severe DAI.

Age-Related Changes in the Association Between Traumatic Brain Injury and Dementia in Older Men and Women

OBJECTIVE

To investigate age-related changes in the association between traumatic brain injury (TBI) and dementia in older men and women separately.

SETTING

A total of 243 general practices in the UK.

PARTICIPANTS

This study included 4760 patients who received a first TBI diagnosis between 1995 and 2010 (index date), and 4760 patients without TBI who were matched to those with TBI by age, sex, index year, Charlson Comorbidity Index, alcohol dependence, and physician (index date: a randomly selected visit date).

DESIGN

Retrospective cohort study.

MAIN MEASURES

Incidence of dementia in the decade following index date.

RESULTS

Within 10 years of index date, 8.8% of men with TBI and 4.8% of those without TBI were diagnosed with dementia, while the respective figures were 9.0% and 6.7% in women (P values < .01). There was a significant association between TBI and dementia in men (hazard ratio [HR] = 2.29, 95% confidence interval [CI]: 1.64-3.19) and in women (HR = 1.33, 95% CI: 1.07-1.64). Furthermore, the association between TBI and dementia was significant in men aged 60 to 70 (HR = 2.51, 95% CI: 1.27-4.96) and 71 to 80 years (HR = 3.00, 95% CI: 1.82-4.93), whereas the relationship was only significant and potentially unreliable in women aged 81 to 90 years (HR = 1.49, 95% CI: 1.03-2.14).

CONCLUSIONS

The age-related relationship between TBI and dementia differed between men and women. More research of a prospective nature and including behavioral data is needed to better understand these differences.

TBI as a Risk Factor for Substance Use Behaviors: A Meta-analysis

OBJECTIVE

To quantify the relationship between substance use behaviors before and after traumatic brain injury (TBI), to identify populations that may benefit more from targeted interventions to reduce the effect of substance use on TBI recovery, and to establish areas for further study.

DATA SOURCES

Studies were identified via literature searches using MEDLINE, PsychInfo, PsychArticles, PubMed, and GoogleScholar (published before January 2019), as well as reference section reviews and forward searches. Searches were conducted using search terms for TBI and substance use behaviors.

STUDY SELECTION

Studies were included if they (1) contained both a measure of TBI and a measure of substance use behaviors; (2) reported an effect size representing the relationship between substance use behaviors before and after TBI, compared TBI vs non-TBI groups on substance use behaviors controlling for pre-TBI substance use, or compared groups with differing TBI severity on subsequent substance use behaviors controlling for pre-TBI substance use; (3) were written in English; and (4) were human subjects research. Studies examining effects of substance use intervention for people sustaining TBI were excluded from this study.

DATA EXTRACTION

Study variables included substance use behaviors, TBI severity, time since TBI, military status, age, race, and sex.

DATA SYNTHESIS

Substance use behaviors had a small but statistically significant decrease after moderate-severe TBI. After moderate-severe TBI, there was a statistically significant decline in both substance use (d=-0.29, P<.01) and negative substance use consequences (d=-0.67, P=.01). There was no significant change in substance use behaviors after mild TBI.

CONCLUSIONS

Substance use behaviors had a small decrease after moderate to severe TBI and no significant change after mild TBI. Study findings suggest the need for accurate assessment to identify those at greatest risk for problematic substance use behaviors after TBI.

The Effect of Cerebrolysin on the Predictive Value of Baseline Prognostic Risk Score in Moderate and Severe Traumatic Brain Injury

Cognitive dysfunction is a significant complaint among patients after moderate to severe traumatic brain injury (TBI), with devastating consequences on functional recovery and quality of life. Prognostic models allow a better assessment and management of neurotrauma patients.

The aim of the study was to demonstrate the predictive value of the Baseline Prognostic Risk Score (BPRS) in moderate to severe TBI, in a sample of patients treated with neurotrophic factors.

Eighty patients with moderate-severe TBI from the CAPTAIN II study were included in secondary data analysis. Patients received active treatment with Cerebrolysin, 50 mL per day for ten days, followed by two treatment cycles with 10 mL per day for ten days. BPRS was determined on admission; the age was recorded, and patients were evaluated using the following neurocognitive tests: Mini-Mental State Essay (MMSE), Wechsler Adult Intelligence Scale-Third Edition Processing Speed Index (WAIS-III PSI) and Stroop Colour Word Test-Victoria Version at 10, 30 and 90 days. Hierarchical regression analysis was performed to investigate the unique predictive value of BPRS on cognitive evolution, independent of age. BPRS independently predicted scores on the WAIS-III PSI DSCales and the Word subscale of the Stroop Colour Word Test at 90 days. Age was a significant predictor for all the investigated scales at 10, 30, and 90 days.

This study demonstrates the predictive value of a validated prognostic model (BPRS) for medium-term neurocognitive outcomes in a sample of moderate-severe traumatic brain injury treated with neurotrophic factors.

Cognitive Reserve Proxies Do Not Differentially Account for Cognitive Performance in Patients with Focal Frontal and Non-Frontal Lesions

OBJECTIVE

Cognitive reserve (CR) suggests that premorbid efficacy, aptitude, and flexibility of cognitive processing can aid the brain's ability to cope with change or damage. Our previous work has shown that age and literacy attainment predict the cognitive performance of frontal patients on frontal-executive tests. However, it remains unknown whether CR also predicts the cognitive performance of non-frontal patients.

METHOD

We investigated the independent effect of a CR proxy, National Adult Reading Test (NART) IQ, as well as age and lesion group (frontal vs. non-frontal) on measures of executive function, intelligence, processing speed, and naming in 166 patients with focal, unilateral frontal lesions; 91 patients with focal, unilateral non-frontal lesions; and 136 healthy controls.

RESULTS

Fitting multiple linear regression models for each cognitive measure revealed that NART IQ predicted executive, intelligence, and naming performance. Age also significantly predicted performance on the executive and processing speed tests. Finally, belonging to the frontal group predicted executive and naming performance, while membership of the non-frontal group predicted intelligence.

CONCLUSIONS

These findings suggest that age, lesion group, and literacy attainment play independent roles in predicting cognitive performance following stroke or brain tumour. However, the relationship between CR and focal brain damage does not differ in the context of frontal and non-frontal lesions.

Past Life Experiences and Neurological Recovery: The Role of Cognitive Reserve in the Rehabilitation of Severe Post-Anoxic Encephalopathy and Traumatic Brain Injury

OBJECTIVE

Patients with an equivalent clinical background may show unexpected interindividual differences in their outcome. The cognitive reserve (CR) model has been proposed to account for such discrepancies, but its role after acquired severe injuries is still being debated. We hypothesize that inappropriate investigative methods might have been used when dealing with severe patients, which have very likely reduced the possibility of observing meaningful influences in recovery from severe traumas.

METHODS

To overcome this issue, the potential neuroprotective role of CR was investigated, considering a wider spectrum of clinical symptoms ranging from low-level brain stem functions necessary for life to more complex motor and cognitive skills. In the present study, data from 50 severe patients, 20 suffering from post-anoxic encephalopathy (PAE) and 30 with traumatic brain injury (TBI), were collected and retrospectively analyzed.

RESULTS

We found that CR, diagnosis, time of hospitalization, and their interaction had an effect on the clinical indexes. When the predictive power of CR was investigated by means of two machine learning classifier algorithms, CR, together with age, emerged as the strongest factor in discriminating between patients who reached or did not reach successful recovery.

CONCLUSIONS

Overall, the present study highlights a possible role of CR in shaping the recovery of severe patients suffering from either PAE or TBI. The practical implications underlying the need to routinely considered CR in the clinical practice are discussed.

Baseline Predictors of Survival, Neurological Recovery, Cognitive Function, Neuropsychiatric Outcomes, and Return to Work in Patients after a Severe Traumatic Brain Injury: an Updated Review

Introduction

Severe traumatic brain injury (sTBI) is a common cause of death and disability worldwide, with long-term squeal among survivors that include cognitive deficits, psychosocial and neuropsychiatric dysfunction, failure to return to pre-injury levels of work, school and inter-personal relationships, and overall reduced quality of and satisfaction with life.

Aim

The aim of this work is to review the current literature on baseline predictors of outcomes in adults post sTBI.

Method

Most of available literature on baseline predictors of outcomes in adults post sTBI were reviewed and summarized in this work.

Results

Currently, a sizeable number of composite predictors of mortality and overall function exists; however, these instruments tend to over-estimate poor outcomes and fail to address issues like cognition, psychosocial/ neuropsychiatric dysfunction, and return to work or school.

Conclusion

This article reviews currently-identified predictors of all these outcomes.

The need to incorporate aged animals into the preclinical modeling of neurological conditions

Neurological conditions such as traumatic brain injury, stroke, Parkinson's disease, epilepsy, multiple sclerosis, and Alzheimer's disease are serious clinical problems that affect millions of people worldwide. The majority of clinical trials for these common conditions have failed, and there is a critical need to understand why treatments in preclinical animal models do not translate to patients. Many patients with these conditions are middle-aged or older, however, the majority of preclinical studies have used only young-adult animals. Considering that aging involves biological changes that are relevant to the pathobiology of neurological diseases, the lack of aged subjects in preclinical research could contribute to translational failures. This paper details how aging affects biological processes involved in neurological conditions, and reviews aging research in the context of traumatic brain injury, stroke, Parkinson's disease, epilepsy, multiple sclerosis, and Alzheimer's disease. We conclude that aging is an important, but often overlooked, factor that influences biology and outcomes in neurological conditions, and provide suggestions to improve our understanding and treatment of these diseases in aged patients.

The Role of Cognitive Reserve in Recovery From Traumatic Brain Injury

OBJECTIVE

To examine whether cognitive reserve (CR) attenuates the initial impact of traumatic brain injury (TBI) on cognitive performance (neural reserve) and results in faster cognitive recovery rates in the first year postinjury (neural compensation), and whether the advantage of CR differs on the basis of the severity of TBI.

SETTING

Inpatient/outpatient clinics at an academic medical center.

PARTICIPANTS

Adults with mild TBI (mTBI; n = 28), complicated mild TBI (cmTBI; n = 24), and moderate to severe TBI (msevTBI; n = 57), and demographically matched controls (n = 66).

DESIGN

Retrospective, longitudinal cohort assessed at 1, 6, and 12 months postinjury.

MAIN MEASURES

Outcomes were 3 cognitive domains: processing speed/executive function, verbal fluency, and memory. Premorbid IQ, estimated with the Wechsler Test of Adult Reading, served as CR proxy.

RESULTS

Higher premorbid IQ was associated with better performance on cognitive domains at 1 month postinjury, and the effect of IQ was similarly beneficial for all groups. Cognitive recovery rate was moderated only by TBI severity; those with more severe TBI had faster recovery in the first year.

CONCLUSION

Results support only the neural reserve theory of CR within a TBI population and indicate that CR is neuroprotective, regardless of the degree of TBI. Higher premorbid CR does not allow for more rapid adaptation and recovery from injury.

The Association of Cognitive Reserve in Chronic-Phase Functional and Neuropsychological Outcomes Following Traumatic Brain Injury

OBJECTIVE

Examine the association of cognitive reserve (CR) factors (estimated premorbid intelligence quotient [IQ], years of education, and occupational attainment) and traumatic brain injury (TBI) severity with functional and neuropsychological outcomes 1 to 5 years following TBI.

PARTICIPANTS

Patients with mild (N = 58), moderate (N = 25), or severe (N = 17) TBI.

MAIN MEASURES

Cognitive reserve factors (estimated premorbid IQ, years of education, and occupational attainment); neuropsychological test battery; Glasgow Outcome Scale-Extended; Short Form-36 Health Survey.

ANALYSES

Spearman-Brown correlations, linear regression models, and analyses of covariance were used to analyze the relation between CR factors and outcome measures.

RESULTS

Analyses revealed significant relations between estimated premorbid IQ and neuropsychological outcomes (P < .004): California Verbal Learning Test, Wechsler Adult Intelligence Scale-Fourth Edition working memory, Booklet Category Test, Trail Making Test B, and Grooved Pegboard Test. There was also a significant correlation between estimated premorbid IQ and Wechsler Adult Intelligence Scale-Fourth Edition processing speed. Years of education had significant relations with California Verbal Learning Test and Wechsler Adult Intelligence Scale-Fourth Edition working memory and processing speed scores. There were significant differences between TBI severity groups and performance on the Trail Making Test A, Grooved Pegboard Test, and Finger Tapping Test.

CONCLUSIONS

Cognitive reserve factors may be associated with outcomes following TBI. Additional alternatives to TBI severity are needed to help guide rehabilitative planning postinjury.

Traumatic Brain Injury as a Risk Factor for Dementia and Alzheimer Disease: Critical Review of Study Methodologies

Despite much previous research stating that traumatic brain injury (TBI) has been confirmed as a risk factor for dementia and Alzheimer disease (AD), findings from observational studies are mixed and are of low methodological quality. This review aimed to critically evaluate the methodologies used in previous studies. Relevant literature was identified by examining reference lists for previous reviews and primary studies, and searches in MEDLINE, PubMed, Google Scholar, and Research Gate. Sixty-eight identified reports, published between 1982 and August 2018, met inclusion criteria. Common methodological weaknesses included self-reported TBI (62%); poor TBI case definition (55%); low prevalence of TBI in samples (range 0.07-28.7%); reverse causality (86% moderate to high risk of reverse causality); not controlling for important confounding factors. There were also key areas of methodological rigor including use of individual matching for cases and controls (57%); gold standard dementia and AD criteria (53%); symmetrical data collection (65%); large sample sizes (max, 2,794,752); long follow-up periods and controlling of analyses for age (82%). The quality assessment revealed methodological problems with most studies. Overall, only one study was identified as having strong methodological rigor. This critical review identified several key areas of methodological weakness and rigor and should be used as a guideline for improving future research. This can be achieved by using longitudinal prospective cohort designs, with medically confirmed and well characterized TBI sustained sufficient time before the onset of dementia, including appropriate controls and informants, and considering the impacts of known protective and risk factors.

Depression as a Predictor of Long-term Employment Outcomes Among Individuals With Moderate-to-Severe Traumatic Brain Injury

OBJECTIVE

To examine the predictive ability of depression when considering long-term employment outcomes for individuals with moderate-to-severe traumatic brain injury (TBI) after controlling for key preinjury and injury-related variables.

DESIGN

Secondary data analysis.

SETTING

Community follow-up after discharge from an inpatient rehabilitation center.

PARTICIPANTS

Individuals between 18 and 60 years old with moderate-to-severe TBI enrolled in the Traumatic Brain Injury Model Systems database.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Employment status.

RESULTS

The prevalence of employment at 2 and 5 years post injury was 40.3% and 44.5%, respectively. Individuals identified as depressed at 1 year were more likely to be unemployed at 2 years post injury (odds ratio [OR], 1.77; 95% CI, 1.38-2.27; P<.0001). Similar relations between current depression and future employment were observed from 1- and 2-year depression status predicting 5-year employment (1-year: OR, 1.88; 95% CI, 1.48-2.40; P<.0001: 2-year: OR, 1.72; 95% CI, 1.36-2.17; P<.0001).

CONCLUSIONS

After controlling for baseline predictors variables, the experience of postinjury depression-a modifiable condition-contributes predictive ability to future employment outcomes. Incorporating assessments and/or interventions for depression into postacute rehabilitation programs could promote favorable employment outcomes after TBI.

Patterns of recovery course in early intervention for FIRST episode non-affective psychosis patients: The role of timing

BACKGROUND

Prevention of symptom relapse and promotion of functional recovery are the two main goals of early intervention following a first episode of non-affective psychosis (FEP). The identification of patterns of recovery is important in developing and implementing recovery focused interventions at set time interval.

METHOD

Patterns of recovery course, in terms of symptomatic and functional remission, were explored at 1 and 3-year follow-up in a sample of 373 consecutive FEP patients. Relapses during this period were considered.

RESULTS

Four patterns of recovery course were defined: good stable (26%), good unstable (21%), poor unstable (10%), poor stable (43%). Those who met criteria for good stable recovery were more likely have less severe baseline negative symptoms (OR = 2.092; 95% CI = 0.99-4.419) and to not be diagnosed with schizophrenia (OR = 2.242; 95% CI = 1.015-4.954). Short DUP (OR = 2.152; 95% CI = 0.879-5.27) and low premorbid IQ (OR = 2.281; 95% CI = 0.954-5.457) increased the likelihood of good unstable recovery. Less severe baseline negative symptoms (OR = 3.851; 95% CI = 1.422-10.435) and single status (OR = 4.307; 95% CI = 1.014-18.293) increased the likelihood of a poor unstable recovery. Poor unstable pattern was significantly associated with a high relapse rate (73%).

CONCLUSIONS

Our results shed light on identifying different recovery patterns in FEP. Despite evidence for early intervention effectiveness, we should explore ways to prevent relapse and improve long-term recovery, particularly in reference to the role of timing in the design of interventions.

The effect of subjective perception of cognition on emotional functioning in adults with long-term neurological and neuropsychiatric disorders

Purpose: To examine effects of subjective perception and objective status of cognition on emotional functioning in a sample of adults with long-term neurological and neuropsychiatric disorders.Method: N = 65. Subjective measures were derived from the self-ratings on the Problem Checklist (PCL) from the HI-FI; the objective status was represented by combined externally standardised scores on neuropsychological tests across three cognitive domains: verbal memory, executive functioning, and psychomotor speed.Results: No relationship was found between self-ratings of cognitive competence and performance on neuropsychological tests. Based on the results of the multiple regression analysis, approximately 40% of the variability in emotional functioning was explained by self-perceived cognitive and physical competence, while the addition of objective measures of cognition increased predictive capacity by only 1.3%. The awareness scores were calculated as the difference between objective performance scores and self-ratings of cognition. Overall, the sample demonstrated a tendency towards low awareness of cognitive deficits. Patients who overestimated cognitive deficits self-rated emotional functioning at a significantly lower level, while those with average or low awareness of deficits were equally emotionally content.Conclusions: Self-perception of competence, rather than objective level of functioning influence emotional well-being and quality of life in individuals with long-term disabilities in our study.IMPLICATIONS FOR REHABILITATIONCognitive deficits are common consequences of neurological dysfunction.This study shows that self-perception of cognitive competence, rather than objective level of cognitive functioning has critical influence on emotional well-being and perceived quality of life.An addition of psychotherapeutic intervention directed at alleviation of self-perception bias is likely to improve emotional well-being and enhance efficiency of rehabilitation efforts in patients with long-term disabilities due to neurological disorders.Based on our findings, patients with long-term disabilities could benefit from psychotherapy to improve their self-perception and quality of life.

Cognitive Reserve Protects Against Memory Decrements Associated With Neuropathology in Traumatic Brain Injury

OBJECTIVE

To evaluate whether cognitive reserve (CR) moderates the relationship between neuropathology and cognitive outcomes after traumatic brain injury (TBI).

SETTING

Outpatient research organization.

PARTICIPANTS

Patients with complicated mild (n = 8), moderate (n = 9), and severe (n = 44) TBI.

DESIGN

Prospective, cross-sectional study.

MAIN MEASURES

Cognitive reserve was estimated using a test of word reading (Wechsler Test of Adult Reading). Diffusion tensor imaging (functional anisotropy) was used to quantify neuropathology. Neuropsychological test scores were submitted to principal components analyses to create cognitive composites for memory, attention, executive function, and processing speed domains.

RESULTS

At lower levels of neuropathology, people with higher CR exhibited better memory than those with lower CR. This benefit diminished as neuropathology increased and disappeared at the highest levels of neuropathology. Cognitive reserve ceased exerting a protective effect at premorbid intelligence levels below average.

CONCLUSION

Cognitive reserve may differentially protect some cognitive domains against neuropathology relative to others. A clinical cutoff below which CR is no longer protective, together with a possible neuropathology ceiling effect, may be instructive for prognostication and clinical decision-making in cognitive rehabilitation.

Traumatic Brain Injury, Chronic Traumatic Encephalopathy, and Alzheimer Disease

Traumatic brain injury (TBI) is a major health and economic burden. With increasing aging population, this issue is expected to continue to rise. Neurodegenerative disorders are more common with aging population in general regardless of history of TBI. Recent evidence continues to support a relation between a TBI and neurocognitive decline later in life (such as in athletes and military). This article summarizes the pathologic and clinical effects of TBI (regardless of severity) on the later development of dementia in individuals 65 years or older.

Functional Outcomes and Health-Related Quality of Life After Severe Traumatic Brain Injury: A Review

Throughout recovery, patients with severe traumatic brain injury (TBI) show physical and functional improvement, but continue to have cognitive and psychosocial problems. The aim of this article was to review the literature regarding the functional and health-related quality of life (HRQOL) outcomes in severe TBI. There were 15 articles reviewed, 13 of them were quantitative studies and two were narrative review. Most of the articles showed an improvement occurs rapidly at 6 months post-injury. There were several factors that influence the outcome after TBI, most of it was the Glasgow Coma Scale (GCS) on admission, age, educational level, duration of posttraumatic amnesia (PTA), and length of stay (LOS) in the Intensive Care Unit (ICU). Thus, health care workers should help the survivors of severe TBI in the recovery process to ensure the latter can attain maximum function and quality of life.