Functional recovery after moderate/severe traumatic brain injury: a role for cognitive reserve?

Serum NfL and GFAP as biomarkers of progressive neurodegeneration in TBI

BACKGROUND

We examined spatial patterns of brain atrophy after mild, moderate, and severe traumatic brain injury (TBI), the relationship between progression of brain atrophy with initial traumatic axonal injury (TAI), cognitive outcome, and with serum biomarkers of brain injury.

METHODS

A total of 143 patients with TBI and 43 controls were studied cross-sectionally and longitudinally up to 5 years with multiple assessments, which included brain magnetic resonance imaging, cognitive testing, and serum biomarkers.

RESULTS

TBI patients showed progressive volume loss regardless of injury severity over several years, and TAI was independently associated with accelerated brain atrophy. Cognitive performance improved over time. Higher baseline serum neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) were associated with greater rate of brain atrophy over 5 years.

DISCUSSSION

Spatial patterns of atrophy differ by injury severity and TAI is associated with the progression of brain atrophy. Serum NfL and GFAP show promise as non-invasive prognostic biomarkers of progressive neurodegeneration in TBI.

HIGHLIGHTS

In this longitudinal study of patient with mild, moderate, and severe traumatic brain injury (TBI) who were assessed with paired magnetic resonance imaging (MRI), blood biomarkers, and cognitive assessments, we found that brain atrophy after TBI is progressive and continues for many years even after a mild head trauma without signs of brain injury on conventional MRI. We found that spatial pattern of brain atrophy differs between mild, moderate, and severe TBI, where in patients with mild TBI , atrophy is mainly seen in the gray matter, while in those with moderate to severe brain injury atrophy is predominantly seen in the subcortical gray matter and whiter matter. Cognitive performance improves over time after a TBI. Serum measures of neurofilament light or glial fibrillary acidic protein are associated with progression of brain atrophy after TBI.

The Australian Traumatic Brain Injury Initiative: Systematic Review and Consensus Process to Determine the Predictive Value of Demographic, Injury Event, and Social Characteristics on Outcomes for People With Moderate-Severe Traumatic Brain Injury

The objective of the Australian Traumatic Brain Injury (AUS-TBI) Initiative is to develop a data dictionary to inform data collection and facilitate prediction of outcomes of people who experience moderate-severe TBI in Australia. The aim of this systematic review was to summarize the evidence of the association between demographic, injury event, and social characteristics with outcomes, in people with moderate-severe TBI, to identify potentially predictive indicators. Standardized searches were implemented across bibliographic databases to March 31, 2022. English-language reports, excluding case series, which evaluated the association between demographic, injury event, and social characteristics, and any clinical outcome in at least 10 patients with moderate-severe TBI were included. Abstracts and full text records were independently screened by at least two reviewers in Covidence. A pre-defined algorithm was used to assign a judgement of predictive value to each observed association. The review findings were discussed with an expert panel to determine the feasibility of incorporation of routine measurement into standard care. The search strategy retrieved 16,685 records; 867 full-length records were screened, and 111 studies included. Twenty-two predictors of 32 different outcomes were identified; 7 were classified as high-level (age, sex, ethnicity, employment, insurance, education, and living situation at the time of injury). After discussion with an expert consensus group, 15 were recommended for inclusion in the data dictionary. This review identified numerous predictors capable of enabling early identification of those at risk for poor outcomes and improved personalization of care through inclusion in routine data collection.

The role of cognitive reserve in traumatic brain injury: a systematic review of observational studies

OBJECTIVE

Evaluate the role of cognitive reserve (CR) on cognitive and physical sequelae in traumatic brain injury (TBI).

METHODS

A comprehensive search strategy was conducted in four databases in English and Spanish in the last 12 years (2011-2023). Inclusion criteria: original cross-sectional and longitudinal studies whose main or secondary objective was to evaluate the effect of CR in adult patients with TBI. PRISMA guidelines were used to report the search and selection method and STROBE checklist was used to evaluate the quality of studies.

RESULTS

Eighteen observational studies were included in this review. Multiple sources of variability were observed: number of patients, time of evolution, severity of the TBI, type of CR proxy, cognitive assessment instrument, etc. However, the most commonly used indicators of CR were premorbid IQ and educational attainment. A positive and consistent association between CR and performance on cognitive tests after injury was found.

CONCLUSIONS

CR has a consistent positive effect on cognition and on some other aspects of recovery in traumatic brain injury. In future studies, it will be necessary to promote the use of CR indices based on various indicators and explore the effects of CR on other aspects related to the recovery of brain trauma.

The utility of the Cognitive Reserve Index questionnaire in chronic traumatic brain injury

Objective: This study examined the relationship between cognitive reserve measured with the Cognitive Reserve Index questionnaire (CRIq) and cognitive and functional outcomes in a chronic traumatic brain injury (TBI) cohort compared to a non-TBI cohort. The utility of the CRIq was compared to common proxies of cognitive reserve (premorbid IQ and years of education) in TBI and non-TBI cohorts. Method: Participants were 105 individuals with moderate-severe TBI (10-33 years post injury) and 91 participants without TBI. Cognitive outcome was examined across four cognitive factors; verbal memory, visual ability and memory, executive attention, and episodic memory. Functional outcome was measured using the Glasgow Outcome Scale Extended. The CRIq total score and three subscale scores (education, work, leisure) were examined. Results: In the TBI cohort, associations were identified between two CRIq subscales and cognitive factors (CRIq education and verbal memory; CRIq work and executive attention). There were no associations between CRIq leisure and cognitive outcomes, or between CRIq and functional outcome. Model selection statistics suggested premorbid IQ and years of education provided a better fit than the CRIq for the relationship between cognitive reserve with two cognitive factors and functional outcome, with neither model providing an improved fit for the remaining two cognitive factors. This finding was broadly consistent in the non-TBI cohort. Conclusion: Cognitive reserve contributes significantly to long-term clinical outcomes following moderate-severe TBI. The relationship between cognitive reserve and long-term cognitive and functional outcomes following TBI is best characterised with traditional proxies of cognitive reserve, mainly premorbid IQ, rather than the CRIq.

Memory for social media images following traumatic brain injury

PRIMARY OBJECTIVE

An emerging body of research examines the role of computer-mediated communication in supporting social connection in persons with traumatic brain injury (TBI). We examine the cognitive impacts of engaging with images posted to social media for persons with moderate-severe TBI.

RESEARCH DESIGN

Prior work shows that after viewing social media posts, adults have better memory for posts when they generate a comment about the post. We examined if persons with TBI experience a memory benefit for commented-upon social media images similar to non-injured comparison participants.

METHODS AND PROCEDURES

53 persons with moderate-to-severe TBI and 52 non-injured comparison participants viewed arrays of real social media images and were prompted to comment on some of them. After a brief delay, a surprise two-alternative forced choice recognition memory test measured memory for these images.

MAIN OUTCOMES AND RESULTS

Persons with TBI remembered social media images at above-chance levels and experienced a commenting-related memory boost much like non-injured comparison participants.

CONCLUSIONS

These findings add to a growing literature on the potential benefits of social media use in individuals with TBI and point to the benefits of active engagement for memory in social media contexts in TBI.

Participant diversity in Psychophysiology

The Society for Psychophysiological Research and accompanying journal, Psychophysiology, have increasingly incorporated diversity and inclusion into their posted values, conference programming, and science. Much of this focus on equity, diversity, and inclusion work has occurred since 2010. The current review content analyzed the articles published in Psychophysiology from 2010 through 2020 to determine if SPR and Psychophysiology's commitment to diversity and inclusion has resulted in changes to reporting and analysis of participant demographics. Demographic reporting practices were compared to APA reporting standards and the use of demographic variables assessed according to the guidance proffered in the introduction to Psychophysiology's 2016 Special Issue on Diversity and Representation. Results of the content analysis indicated near perfect reporting of biological sex and frequent reporting of average age. Age range and educational attainment were reported in over half of studies, while race or ethnicity were reported in only 17%. Socioeconomic status, income, gender identity, and sexual orientation were almost never reported. In over 60% of studies at least one major demographic variable was reported, but was not used in preliminary, main, or supplementary analyses as a covariate, moderator, or otherwise. SPR and Psychophysiology should continue advocating for increased reporting of major demographic variables and ethical analysis of demographic modulation of various psychophysiological mechanisms. We provide a preliminary template of reporting standards and call for the inclusion of more open science practices by psychophysiologists.

Predictors of High School and College Graduation After Sustaining a Moderate-to-Severe Traumatic Brain Injury

OBJECTIVE

To identify early predictors of US high school and college graduation after moderate-to-severe traumatic brain injury (TBI).

SETTING

Inpatient rehabilitation and community.

PARTICIPANTS

TBI Model Systems participants, aged 16 to 24 years, enrolled as high school or college students at time of injury.

DESIGN

Prospective cohort study.

MAIN MEASURES

Successful graduation was defined as having a diploma (high school) or an associate/bachelor's degree (college) at 1-, 2-, or 5-year follow-up. Predictors were sex, race/ethnicity, urbanicity, preinjury substance abuse, primary rehabilitation payer, and functional independence at inpatient rehabilitation discharge.

METHOD

We descriptively characterized differences between those who did and did not graduate high school and college within the first 5 years postinjury and identified early predictors of successful high school and college graduation using 2 binomial logistic regressions.

RESULTS

Of those with known graduation status, 81.2% of high school and 41.8% of college students successfully graduated. Graduates in both groups were more often White than Black and had more functional independence at discharge. Among high school students, preinjury substance abuse was also a risk factor for not graduating, as was identifying as Hispanic or "other" race.

CONCLUSIONS

Sociodemographic factors and disability influence graduation outcomes, requiring structural, institutional, and personal interventions for success.

A genetics-first approach to understanding autism and schizophrenia spectrum disorders: the 22q11.2 deletion syndrome

Recently, increasing numbers of rare pathogenic genetic variants have been identified that are associated with variably elevated risks of a range of neurodevelopmental outcomes, notably including Autism Spectrum Disorders (ASD), Schizophrenia Spectrum Disorders (SSD), and Intellectual Disability (ID). This review is organized along three main questions: First, how can we unify the exclusively descriptive basis of our current psychiatric diagnostic classification system with the recognition of an identifiable, highly penetrant genetic risk factor in an increasing proportion of patients with ASD or SSD? Second, what can be learned from studies of individuals with ASD or SSD who share a common genetic basis? And third, what accounts for the observed variable penetrance and pleiotropy of neuropsychiatric phenotypes in individuals with the same pathogenic variant? In this review, we focus on findings of clinical and preclinical studies of the 22q11.2 deletion syndrome (22q11DS). This particular variant is not only one of the most common among the increasing list of known rare pathogenic variants, but also one that benefits from a relatively long research history. Consequently, 22q11DS is an appealing model as it allows us to: (1) elucidate specific genotype-phenotype associations, (2) prospectively study behaviorally defined classifications, such as ASD or SSD, in the context of a known, well-characterized genetic basis, and (3) elucidate mechanisms underpinning variable penetrance and pleiotropy, phenomena with far-reaching ramifications for research and clinical practice. We discuss how findings from animal and in vitro studies relate to observations in human studies and can help elucidate factors, including genetic, environmental, and stochastic, that impact the expression of neuropsychiatric phenotypes in 22q11DS, and how this may inform mechanisms underlying neurodevelopmental expression in the general population. We conclude with research priorities for the field, which may pave the way for novel therapeutics.

Cognitive reserve index and long-term disability in patients with severe traumatic brain injury discharged from the intensive rehabilitation unit

Objectives

The "cognitive reserve" (CR) theory posits that higher premorbid cognitive activities can mitigate the effects of brain damage. This study aimed to investigate the association between CR and long-term functional autonomy in patients surviving a severe traumatic brain injury (sTBI).

Setting

Data were collected from the database of inpatients with severe acquired brain injury in a rehabilitation unit admitted from August 2012 to May 2020.

Participants

Patients that had incurred an sTBI, aged 18+ years, completing the phone Glasgow Outcome Scale-Expanded at follow-up (pGOS-E) in absence of previous brain trauma or neurological disease, or cognitive disorders were included. Patients with severe brain injury from non-traumatic etiologies were not included in the study.

Design

In this longitudinal study, all patients underwent a multidimensional assessment including the cognitive reserve index questionnaire (CRIq), the coma recovery scale-revised, the level of cognitive functioning, the Disability Rating Scale (DRS), and the Galveston Orientation and Amnesia Test at admission. At discharge, functional scales were administered again together with the Glasgow Outcome Scale. The pGOS-E was assessed at follow-up.

Main measures

pGOS-E.

Results

A total of 106 patients/caregivers underwent the pGOS-E after 5.8 [3.6] years from the event. Among them, 46 (43.4%) died after discharge, and 60 patients [men: 48 (80%); median age: 54 years; median time post-onset: 37 days; median education level: 10 years; median CRIq total score: 91] were included in the analysis exploring the association between pGOS-E and demographic data, cognitive reserve surrogates, and clinical variables at admission and discharge from the rehabilitation unit. A younger age (B = -0.035, p = 0.004) and a lower DRS category at discharge (B = -0.392, p = 0.029) were significantly related to a higher long-term functional autonomy in the multivariate analysis.

Conclusion

Long-term functional autonomy was not influenced by CR as assessed through the educational level and the CRIq.

Measuring long-term outcomes after injury: current issues and future directions

Maximizing long-term outcomes for patients following injury is the next challenge in the delivery of patient-centered trauma care. The following review outlines three important components in trauma outcomes: (1) data gathering and monitoring, (2) the impact of traumatic brain injury, and (3) trajectories in recovery and identifies knowledge gaps and areas for needed future research.

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).

Assessment of the individual and compounding effects of marginalization factors on injury severity, discharge location, recovery, and employment outcomes at 1 year after traumatic brain injury

Objective

The aim of this study is to examine the effect of eight distinct marginalized group memberships and explore their compounding effect on injury severity, recovery, discharge location, and employment outcomes 1-year after traumatic brain injury (TBI).

Methods

Individuals with medically confirmed, complicated mild-severe TBI (N = 300) requiring inpatient rehabilitation care between the ages of 18 and 65 were recruited at two urban (public and private) health systems between 2013 and 2019. Data were collected from self-report and medical record abstraction. Marginalized group membership (MGM) includes racial and ethnic minority status, less than a high school diploma/GED, limited English proficiency, substance abuse, homelessness, psychiatric hospitalizations, psychiatric disorders, and incarceration history. Membership in four or more of these groups signifies high MGM. In addition, these factors were explored individually. Unadjusted and adjusted linear and logistic regressions and Kruskal–Wallis tests were used to assess the associations of interest in RStudio.

Results

After adjusting for age, sex, and cause of injury, compared to TBI patients with low MGM, those with high MGM experience significantly longer post-traumatic amnesia (95% CI = 2.70, 16.50; p = 0.007) and are significantly more likely to have a severe TBI (per the Glasgow-Coma Scale) (95% CI = 1.70, 6.10; p ≤ 0.001) than a complicated mild-moderate injury. Individuals with high MGM also are significantly less likely to be engaged in competitive paid employment 1 year after injury (95% CI = 2.40, 23.40; p = 0.001). Patients with high MGM are less likely to be discharged to the community compared to patients with low MGM, but this association was not significant (95% CI = 0.36, 1.16; p = 0.141). However, when assessing MGMs in isolation, certain associations were not significant in unadjusted or adjusted models.

Conclusion

This exploratory study's findings reveal that when four or more marginalization factors intersect, there is a compounding negative association with TBI severity, recovery, and employment outcomes. No significant association was found between high MGM and discharge location. When studied separately, individual MGMs had varying effects. Studying marginalization factors affecting individuals with TBI has critical clinical and social implications. These findings underline the importance of addressing multidimensional factors concurrent with TBI recovery, as the long-term effects of TBI can place additional burdens on individuals and their economic stability.

Return to School Outcomes among Adults with TBI One Year After Rehabilitation Discharge: A TBIMS Study

OBJECTIVE

To examine return to school outcomes 1 year after traumatic brain injury (TBI) rehabilitation discharge.

DESIGN

Longitudinal observational study using Traumatic Brain Injury Model Systems National Database (TBIMS-NDB) data at 1-year post-TBI.

SETTING

Inpatient rehabilitation centers using follow-up telephone calls.

INDIVIDUALS

Individuals (n = 237) enrolled in the TBIMS-NDB since 2001 between the ages of 18 and 59 years who were engaged in postsecondary education (full or part-time) before recorded TBI.

MAIN MEASURES

Return to school, categorized as in a postsecondary setting at first follow-up (reported hours in school greater than zero at one-year follow-up).

RESULTS

Using an alpha level of 0.05 binary logistic regression analysis identified four predictive variables. Significant predictors of return to school include being of lower age, possessing a higher level of functioning at discharge, reporting lower ratings of disability at discharge, and being able to use a vehicle independently for transportation.

CONCLUSION

Pursuit of higher education is a viable means of community reintegration after TBI. Some individuals with TBI face a myriad of barriers and challenges when returning to school. Study findings may facilitate understanding of how TBI affects return to school and community reintegration outcomes.

Pathway of care for visual and vestibular rehabilitation after mild traumatic brain injury: a critical review

PRIMARY OBJECTIVE

To review the pathway to care for treatment and management of patients receiving visual and vestibular rehabilitation after mild traumatic brain injury (mTBI).

METHODS & PROCEDURES

English scientific peer-reviewed articles from PubMed, CINAHL, Embase, and PsycINFO between 2000 and 2020 were first screened by title and abstract, then those selected underwent full-text review and analysis.

MAIN OUTCOMES & RESULTS

The database search yielded 1640 results and after title and abstract review, 75 articles were selected for full-text screening, from which 8 were included in the qualitative synthesis. Current evidence includes a limited number of retrospective cohort studies and case studies.

CONCLUSIONS

Many patients with visual and vestibular deficits following mTBI do not receive rehabilitation services until months following their injury as there is no standardized pathway to care for patients for visual and vestibular rehabilitation. Barriers to establishing a standardized pathway are the lack of natural history data for visual and vestibular function following mTBI and the lack of randomized clinical trials establishing the efficacy of rehabilitation in patients following mTBI.

Systematic Review and Meta-analysis of Outcome after Mild Traumatic Brain Injury in Older People

OBJECTIVE

Older age is often identified as a risk factor for poor outcome from traumatic brain injury (TBI). However, this relates predominantly to mortality following moderate-severe TBI. It remains unclear whether increasing age exerts risk on the expected recovery from mild TBI (mTBI). In this systematic review of mTBI in older age (60+ years), a focus was to identify outcome through several domains - cognition, psychological health, and life participation.

METHODS

Fourteen studies were identified for review, using PRISMA guidelines. Narrative synthesis is provided for all outcomes, from acute to long-term time points, and a meta-analysis was conducted for data investigating life participation.

RESULTS

By 3-month follow-up, preliminary findings indicate that older adults continue to experience selective cognitive difficulties, but given the data it is possible these difficulties are due to generalised trauma or preexisting cognitive impairment. In contrast, there is stronger evidence across time points that older adults do not experience elevated levels of psychological distress following injury and endorse fewer psychological symptoms than younger adults. Meta-analysis, based on the Glasgow Outcome Scale at 6 months+ post-injury, indicates that a large proportion (67%; 95% CI 0.569, 0.761) of older adults can achieve good functional recovery, similar to younger adults. Nevertheless, individual studies using alternative life participation measures suggest more mixed rates of recovery.

CONCLUSIONS

Although our initial review suggests some optimism in recovery from mTBI in older age, there is an urgent need for more investigations in this under-researched but growing demographic. This is critical for ensuring adequate health service provision, if needed.

The Value of Patient Registries to Advance Basic and Translational Research in the Area of Traumatic Brain Injury

The number of individuals affected by traumatic brain injury (TBI) is growing globally. TBIs may cause a range of physical, cognitive, and psychiatric deficits that can negatively impact employment, academic attainment, community independence, and interpersonal relationships. Although there has been a significant decrease in the number of injury related deaths over the past several decades, there has been no corresponding reduction in injury related disability over the same time period. We propose that patient registries with large, representative samples and rich multidimensional and longitudinal data have tremendous value in advancing basic and translational research and in capturing, characterizing, and predicting individual differences in deficit profile and outcomes. Patient registries, together with recent theoretical and methodological advances in analytic approaches and neuroscience, provide powerful tools for brain injury research and for leveraging the heterogeneity that has traditionally been cited as a barrier inhibiting progress in treatment research and clinical practice. We report on our experiences, and challenges, in developing and maintaining our own patient registry. We conclude by pointing to some future opportunities for discovery that are afforded by a registry model.

Mobile telephone follow-up assessment of postdischarge death and disability due to trauma in Cameroon: a prospective cohort study

OBJECTIVES

In Cameroon, long-term outcomes after discharge from trauma are largely unknown, limiting our ability to identify opportunities to reduce the burden of injury. In this study, we evaluated injury-related death and disability in Cameroonian trauma patients over a 6-month period after hospital discharge.

DESIGN

Prospective cohort study.

SETTING

Four hospitals in the Littoral and Southwest regions of Cameroon.

PARTICIPANTS

A total of 1914 patients entered the study, 1304 were successfully contacted. Inclusion criteria were patients discharged after being treated for traumatic injury at each of four participating hospitals during a 20-month period. Those who did not possess a cellular phone or were unable to provide a phone number were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

The Glasgow Outcome Scale-Extended (GOSE) was administered to trauma patients at 2 weeks, 1 month, 3 months and 6 months post discharge. Median GOSE scores for each timepoint were compared and regression analyses were performed to determine associations with death and disability.

RESULTS

Of 71 deaths recorded, 90% occurred by 2 weeks post discharge. At 6 months, 22% of patients still experienced severe disability. Median (IQR) GOSE scores at the four timepoints were 4 (3-7), 5 (4-8), 7 (4-8) and 7 (5-8), respectively, (p<0.01). Older age was associated with greater odds of postdischarge disability (OR: 1.23, 95% CI: 1.07 to 1.41) and mortality (OR: 2.15, 95% CI: 1.52 to 3.04), while higher education was associated with decreased odds of disability (OR: 0.65, 95% CI: 0.58 to 0.73) and mortality (OR: 0.38, 95% CI: 0.31 to 0.47). Open fractures (OR: 1.73, 95% CI: 1.38 to 2.18) and closed fractures (OR: 1.83, 95% CI: 1.42 to 2.36) were associated with greater postdischarge disability, while higher Injury Severity Score (OR: 2.44, 95% CI: 2.13 to 2.79) and neurological injuries (OR: 4.40, 95% CI: 3.25 to 5.96) were associated with greater odds of postdischarge mortality.

CONCLUSION

Mobile follow-up data show significant morbidity and mortality, particularly for orthopaedic and neurologic injuries, up to 6 months following trauma discharge. These results highlight the need for reliable follow-up systems in Cameroon.

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.

Structural-covariance networks identify topology-based cortical-thickness changes in children with persistent executive function impairments after traumatic brain injury

Paediatric traumatic brain injury (pTBI) results in inconsistent changes to regional morphometry of the brain across studies. Structural-covariance networks represent the degree to which the morphology (typically cortical-thickness) of cortical-regions co-varies with other regions, driven by both biological and developmental factors. Understanding how heterogeneous regional changes may influence wider cortical network organization may more appropriately capture prognostic information in terms of long term outcome following a pTBI. The current study aimed to investigate the relationships between cortical organisation as measured by structural-covariance, and long-term cognitive impairment following pTBI. T1-weighted magnetic resonance imaging (MRI) from n = 83 pTBI patients and 33 typically developing controls underwent 3D-tissue segmentation using Freesurfer to estimate cortical-thickness across 68 cortical ROIs. Structural-covariance between regions was estimated using Pearson's correlations between cortical-thickness measures across 68 regions-of-interest (ROIs), generating a group-level 68 × 68 adjacency matrix for patients and controls. We grouped a subset of patients who underwent executive function testing at 2-years post-injury using a neuropsychological impairment (NPI) rule, defining impaired- and non-impaired subgroups. Despite finding no significant reductions in regional cortical-thickness between the control and pTBI groups, we found specific reductions in graph-level strength of the structural covariance graph only between controls and the pTBI group with executive function (EF) impairment. Node-level differences in strength for this group were primarily found in frontal regions. We also investigated whether the top n nodes in terms of effect-size of cortical-thickness reductions were nodes that had significantly greater strength in the typically developing brain than n randomly selected regions. We found that acute cortical-thickness reductions post-pTBI are loaded onto regions typically high in structural covariance. This association was found in those patients with persistent EF impairment at 2-years post-injury, but not in those for whom these abilities were spared. This study posits that the topography of post-injury cortical-thickness reductions in regions that are central to the typical structural-covariance topology of the brain, can explain which patients have poor EF at follow-up.

Performance-Based Everyday Problem-Solving in Patients With TBI

OBJECTIVE

The present study examined whether the everyday problems test (EPT), a performance-based measure of everyday problem-solving, can be considered a useful test in assessing functional independence in patients with traumatic brain injury (TBI). The relationship between EPT, cognitive abilities (i.e., selective attention, set switching, and working memory) and self-rated measures of everyday functioning and disability in these patients was also assessed.

METHOD

In this case-control study 25 postcomatose outpatients with TBI (age M = 35.9, SD = 14.21) from a neurorehabilitation unit and 25 matched controls were enrolled. Participants were administered the EPT along with neuropsychological tests of selective attention, set switching and working memory, and self-rated measures of everyday functioning and disability.

RESULTS

Patients with TBI were less accurate and slower than controls in the EPT; the two groups were accurately classified based on EPT completion time (likelihood ratio test χ2 = 28.67, R2 = 0.72, p < .001). In the patient group education and selective attention explained a large portion of variance in EPT accuracy (R2 = 0.53, p = .001), while only selective attention explained a significant portion of variance in EPT time (R2 = 0.24, p < .01). Self-rated measures of everyday functioning and disability did not significantly contribute to EPT performance variance.

CONCLUSION

Including performance-based measures as the EPT in a multifactorial approach to assessment can be useful for unraveling cognitive factors contributing to TBI's impact on everyday functioning. Since attentional processes seem to play a significant role in determining EPT performance, rehabilitation of functional independence should target this ability first.

Electroencephalography, Magnetoencephalography, and Cognitive Reserve: A Systematic Review

OBJECTIVE

Cognitive reserve (CR) is the capacity to adapt to (future) brain damage without any or only minimal clinical symptoms. The underlying neuroplastic mechanisms remain unclear. Electrocorticography (ECOG), electroencephalography (EEG), and magnetoencephalography (MEG) may help elucidate the brain mechanisms underlying CR, as CR is thought to be related to efficient utilization of remaining brain resources. The purpose of this systematic review is to collect, evaluate, and synthesize the findings on neural correlates of CR estimates using ECOG, EEG, and MEG.

METHOD

We examined articles that were published from the first standardized definition of CR. Eleven EEG and five MEG cross-sectional studies met the inclusion criteria: They concerned original research, analyzed (M)EEG in humans, used a validated CR estimate, and related (M)EEG to CR. Quality assessment was conducted using an adapted form of the Newcastle-Ottawa scale. No ECOG study met the inclusion criteria.

RESULTS

A total of 1383 participants from heterogeneous patient, young and older healthy groups were divided into three categories by (M)EEG methodology: Eight (M)EEG studies employed event-related fields or potentials, six studies analyzed brain oscillations at rest (of which one also analyzed a cognitive task), and three studies analyzed brain connectivity. Various CR estimates were employed and all studies compared different (M)EEG measures and CR estimates. Several associations between (M)EEG measures and CR estimates were observed.

CONCLUSION

Our findings support that (M)EEG measures are related to CR estimates, particularly in healthy individuals. However, the character of this relationship is dependent on the population and task studied, warranting further studies.

Cognitive Reserve and Anxiety Interactions Play a Fundamental Role in the Response to the Stress

The aims of the present study were to assess the possible interaction between Cognitive Reserve (CR) and State Anxiety (SA) on adrenocortical and physiological responses in coping situations. Forty healthy, middle-aged men completed the Cognitive Reserve Scale and the State-Trait Anxiety Inventory. We used an Observational Fear Conditioning (OFC) paradigm in order to assess emotional learning and to induce stress. Electrodermal activity (EDA) and salivary cortisol concentrations were measured throughout the conditions. Our results indicate that those who indicated having higher state anxiety showed a lower capacity for learning the contingency, along with presenting higher salivary cortisol peak response following the observational fear-conditioning paradigm. The most prominent finding was the interaction between cognitive reserve and state anxiety on cortisol response to the post observational fear-conditioning paradigm. Thus, those who showed a high anxiety-state and, at the same time, a high cognitive reserve did not present an increased salivary cortisol response following the observational fear-conditioning paradigm. Given these results, we postulate that the state anxiety reported by participants, reflects emotional activation that hinders the attention needed to process and associate emotional stimuli. However, cognitive reserve has an indirect relation with conditioning, enabling better emotional learning. In this context, cognitive reserve demonstrated a protective effect on hormonal response in coping situations, when reported anxiety or emotional activation were high. These findings suggest that cognitive reserve could be used as a tool to deal with the effects of stressors in life situations, limiting development of the allostatic load.

Novel approaches to prediction in severe brain injury

PURPOSE OF REVIEW

Recovery after severe brain injury is variable and challenging to accurately predict at the individual patient level. This review highlights new developments in clinical prognostication with a special focus on the prediction of consciousness and increasing reliance on methods from data science.

RECENT FINDINGS

Recent research has leveraged serum biomarkers, quantitative electroencephalography, MRI, and physiological time-series to build models for recovery prediction. The analysis of high-resolution data and the integration of features from different modalities can be approached with efficient computational techniques.

SUMMARY

Advances in neurophysiology and neuroimaging, in combination with computational methods, represent a novel paradigm for prediction of consciousness and functional recovery after severe brain injury. Research is needed to produce reliable, patient-level predictions that could meaningfully impact clinical decision making.

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.

A Population-Based Study of Pre-Existing Health Conditions in Traumatic Brain Injury

Health factors impacting both the occurrence of, and recovery from traumatic brain injury (TBI) vary in complexity, and present genuine challenges to researchers and healthcare professionals seeking to characterize injury consequences and determine prognosis. However, attempts to clarify causal links between injury characteristics and clinical outcomes (including mortality) often compel researchers to exclude pre-existing health conditions (PECs) in their samples, including psychiatric history, medication usage, and other comorbid conditions. In this pre-registered population-based study (total starting n = 939,123 patients), we examined trends in PEC incidence over 22 years in the state of Pennsylvania (1997-2019) in individuals sustaining TBI (n = 169,452) and individuals with orthopedic injury (n = 87,637). The goal was to determine how PECs interact with age and injury severity to influence short-term outcomes. A further goal was to determine whether number of PECs, or specific PEC clusters contributed to worse outcomes within the TBI cohort, compared with orthopedic injury alone. Primary findings indicate that PECs significantly influenced mortality within the TBI cohort; patients having four or more PECs were associated with approximately a two times greater likelihood of dying in acute care (odds ratio [OR] 1.9). Additionally, cluster analyses revealed four distinct PEC clusters that are age and TBI severity dependent. Overall, the likelihood of zero PECs hovers at ∼25%, which is critical to consider in TBI outcomes work and could potentially contribute to the challenges facing intervention science with regard to reproducibility of findings.

Cognitive performance in older adults at three months following mild traumatic brain injury

Introduction: In the context of limited research assessing outcomes following mild traumatic brain injury (mTBI) in older adults, this study evaluated cognitive outcomes through prospective memory, and expected that performance of an older mTBI group (≥65 years) would be lower compared to orthopedic and community controls. The study also explored whether cognitive resources (retrospective memory, executive function) moderated any association between presenting Glasgow Coma Scale (GCS) and prospective memory.Method: At three-months post-injury, a mTBI group (n = 39), an orthopedic control group (n = 63), and a community control group (n = 46) completed a neuropsychological assessment, including (i) prospective memory, using a standardized paper-and-pencil task (Cambridge Prospective Memory Test), an augmented reality task and a naturalistic task, and (ii) standardized measures of retrospective memory (Hopkins Verbal Learning Test) and executive function (Trail Making Test). Group performances were compared, and bootstrapped moderation analyses evaluated the role of cognitive resources in the relationship between GCS and prospective memory outcome.Results: The mTBI group, as compared to community controls, performed significantly lower on the augmented reality task (d = -0.64 to d = -0.79), and there was a small-moderate but non-significant effect (d = -0.45) on the naturalistic task. There were no differences between the mTBI group and orthopedic controls. Retrospective memory was a unique predictor of the augmented reality task (B = 1.83) and moderated the relationship between presenting GCS and the naturalistic task (B = -5.60). Executive function moderated the association between presenting GCS and augmented reality (B = -1.13) and naturalistic task (B = -1.57).Conclusions: At three-months post-mTBI, older adults are at risk of poor cognitive performance; and the relationship between GCS and prospective memory can be moderated by cognitive resources. Further follow-up is indicated to determine whether impairments resolve or persist over time.

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.

Heterogeneity Is a Hallmark of Traumatic Brain Injury, Not a Limitation: A New Perspective on Study Design in Rehabilitation Research

Purpose In both basic science and intervention research in traumatic brain injury (TBI), heterogeneity in the patient population is frequently cited as a limitation and is often interpreted as a factor reducing certainty in the generalizability of research findings and as a source of conflicting findings across studies. Historically, much of TBI research in rehabilitation and cognition has relied upon case-control studies, with small to modest sample sizes. In this context, heterogeneity is indeed a significant limitation. Here, however, we argue that heterogeneity in patient profiles is a hallmark characteristic of TBI and therefore cannot be avoided or ignored. We argue that this inherent heterogeneity must be acknowledged and accounted for prior to study design. Fortunately, advances in statistical methods and computing power allow researchers to leverage heterogeneity, rather than be constrained by it. Method In this article, we review sources of heterogeneity that contribute to challenges in TBI research, highlight methodological advances in statistical analysis and in other fields with high degrees of heterogeneity (e.g., psychiatry) that may be fruitfully applied to decomposing heterogeneity in TBI, and offer an example from our research group incorporating this approach. Conclusion Only by adopting new methodological approaches can we advance the science of rehabilitation following TBI in ways that will impact clinical practice and inform decision making, allowing us to understand and respond to the range of individual differences that are a hallmark in this population.

Marital Stability and Quality of Couple Relationships after Acquired Brain Injury: A Two-Year Follow-Up Clinical Study

Couple relationships after acquired brain injury (ABI) could be vulnerable to emotional distress. Previous evidence has demonstrated significant marital dissatisfaction in the first period after a traumatic event, while long-term evaluations are lacking. In this study, we evaluated the impact of a series of demographic and clinical factors on marital stability after two years from the injury. Thirty-five patients (29% female) with mild/moderate ABI (57% vascular, 43% traumatic) and their partners were enrolled. The couples completed a series of psychological questionnaires assessing marital adjustment (Dyadic Adjustment Scale, DAS) and family functioning (Family Relationship Index, FRI) at discharge from the intensive rehabilitation unit and after 2 years. Demographics (i.e., educational level, job employment and religion commitment) and clinical variables (i.e., the Barthel index, aetiology and brain lesion localization) were considered as predictive factors. Regression analyses revealed that the DAS and FRI values are differently influenced by demographic and clinical factors in patients and caregivers. Indeed, the highest educational level corresponds to better DAS and FRI values for patients. In the spouses, the variability of the DAS values was explained by aetiology (the spouses of traumatic ABI patients had worse DAS values), whereas the variability in the FRI values was explained by religious commitment (spending much time on religious activities was associated with better FRI values). Our data suggest that some clinical and demographic variables might be important for protecting against marital dissatisfaction after an ABI.

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.

Recovery Profiles after Concussion among Male Student-Athletes and Service Cadets with a Family History of Neurodegenerative Disease: Data from the NCAA-DoD CARE Consortium

Preliminary evidence indicates that genetic factors associated with having a family history of neurodegenerative disease (fhNDD) may predispose an individual to persistent symptoms and poorer cognitive performance after concussion. No previous study, however, longitudinally examined athletes with (+) and without (-) a fhNDD. Therefore, we aimed to compare clinical symptoms and cognitive performance of fhNDD+ and fhNDD- athletes at baseline and at multiple time points after concussion. Questionnaire data from the Concussion Assessment, Research and Education (CARE) Consortium were used to identify male athletes and cadets with (n = 51) and without (n = 102) a fhNDD (Alzheimer disease, Parkinson disease, mild cognitive impairment, and non-Alzheimer dementia). All athletes completed the SCAT3 symptom checklist and ImPACT test before their sport season and again within 24-48 h of injury, at the unrestricted return-to-play, and at six months post-concussion. Compared with fhNDD-, fhNDD+ individuals demonstrated greater decrements in visual memory (relative to baseline) 24-48 h post-injury (p < 0.05, d = 0.18). In addition, a main effect of group was observed for impulse control. Compared with fhNDD- athletes, fhNDD+ individuals demonstrated greater decrements in impulse control, 24-48 h post-injury, at the return to play, and at six-month assessments (p < 0.01, d = 0.23). These findings suggest that male athletes with a fhNDD may exhibit greater decrements in cognitive performance after concussion. Small, subtle deficits in cognitive performance may still significantly hinder day-to-day function in student-athletes.

A Self-Administered Multicomponent Web-Based Mental Health Intervention for the Mexican Population During the COVID-19 Pandemic: Protocol for a Randomized Controlled Trial

BACKGROUND

The COVID-19 pandemic has become a public health emergency of international concern; it has not only threatened people's physical health but has also affected their mental health and psychological well-being. It is necessary to develop and offer strategies to reduce the psychological impact of the outbreak and promote adaptive coping.

OBJECTIVE

This study protocol aims to describe a self-administered web-based intervention (Mental Health COVID-19) based on the principles of positive psychology supported by elements of cognitive behavioral therapy and behavioral activation therapy to reduce the symptoms of anxiety and depression and increase positive emotions and sleep quality during and after the COVID-19 outbreak through a telepsychology system.

METHODS

A randomized controlled clinical superiority trial with two independent groups will be performed, with intrasubject measures at four evaluation periods: pretest, posttest, 3-month follow-up, and 6-month follow-up. Participants will be randomly assigned to one of two groups: self-administered intervention with assistance via chat or self-administered intervention without assistance via chat. The total required sample size will be 166 participants (83 per group).

RESULTS

The clinical trial is ongoing. This protocol was approved by the Research Ethics Board of the Free School of Psychology-University of Behavioral Sciences (Escuela libre de Psicología-Universidad de Ciencias del Comportamiento). The aim is to publish the preliminary results in December 2020. A conservative approach will be adopted, and the size effect will be estimated using the Cohen d index with a significance level (α) of .05 (95% reliability) and a conventional 80% power statistic.

CONCLUSIONS

The central mechanism of action will be to investigate the effectiveness of an intervention based on positive psychology through a web platform that can be delivered through computers and tablets, with content that has been rigorously contextualized to the Mexican culture to provide functional strategies to help the target users cope with the COVID-19 pandemic.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04468893; https://clinicaltrials.gov/ct2/show/NCT04468893.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/23117.

A Scoping Review of Predictors of Community Integration Following Traumatic Brain Injury: A Search for Meaningful Associations

OBJECTIVE

The purpose of this scoping review was to identify predictors of community integration for adults with traumatic brain injury.

DATA SOURCES

We searched the PubMed and PsycINFO databases and reviewed references of included studies. We selected studies exploring multiple components of community integration, including instrumental activities of daily living, leisure activities, and social activities. A total of 53 studies were included.

DATA EXTRACTION

We extracted data on sample size and sample characteristics (stage of injury and recovery, severity) and examined predictor variables, outcome measures for community integration, and significant findings, reported as correlations.

DATA SYNTHESIS

We found that the predictors of community integration fell into 4 categories: demographics, injury characteristics, disability and impairments, and environmental factors. There was large variability in reported relationships for demographics (r = 0.01-0.43), injury characteristics (r = 0.01-0.58), disability/functional impairments (r = 0.003-0.98) and environmental factors (r = 0.11-0.58). Cognition, disability, mobility/physical functioning, mood, social support, and length of posttraumatic amnesia had the strongest relationships with community integration outcomes.

CONCLUSIONS

Strategies for the management of cognitive, physical, and emotional functioning, and building and training a strong support system, may facilitate community integration outcomes. Additional work is warranted to further explore the discrepancies found among studies.

Predictors of Access to Rehabilitation in the Year Following Traumatic Brain Injury: A European Prospective and Multicenter Study

BACKGROUND

Although rehabilitation is beneficial for individuals with traumatic brain injury (TBI), a significant proportion of them do not receive adequate rehabilitation after acute care.

OBJECTIVE

Therefore, the goal of this prospective and multicenter study was to investigate predictors of access to rehabilitation in the year following injury in patients with TBI.

METHODS

Data from a large European study (CENTER-TBI), including TBIs of all severities between December 2014 and December 2017 were used (N = 4498 patients). Participants were dichotomized into those who had and those who did not have access to rehabilitation in the year following TBI. Potential predictors included sociodemographic factors, psychoactive substance use, preinjury medical history, injury-related factors, and factors related to medical care, complications, and discharge.

RESULTS

In the year following traumatic injury, 31.4% of patients received rehabilitation services. Access to rehabilitation was positively and significantly predicted by female sex (odds ratio [OR] = 1.50), increased number of years of education completed (OR = 1.05), living in Northern (OR = 1.62; reference: Western Europe) or Southern Europe (OR = 1.74), lower prehospital Glasgow Coma Scale score (OR = 1.03), higher Injury Severity Score (OR = 1.01), intracranial (OR = 1.33) and extracranial (OR = 1.99) surgery, and extracranial complication (OR = 1.75). On contrast, significant negative predictors were lack of preinjury employment (OR = 0.80), living in Central and Eastern Europe (OR = 0.42), and admission to hospital ward (OR = 0.47; reference: admission to intensive care unit) or direct discharge from emergency room (OR = 0.24).

CONCLUSIONS

Based on these findings, there is an urgent need to implement national and international guidelines and strategies for access to rehabilitation after TBI.

Trajectory of 10-Year Neurocognitive Functioning After Moderate-Severe Traumatic Brain Injury: Early Associations and Clinical Application

OBJECTIVE

This study aimed to explore the 10-year trajectories of neurocognitive domains after moderate-severe traumatic brain injury (TBI), to identify factors related to long-term neurocognitive functioning, and to investigate whether performance remained stable or changed over time.

METHOD

Seventy-nine patients with moderate-severe TBI between the ages of 16 and 55 years were assessed at 3 months, 1, 5, and 10 years postinjury using neuropsychological tests and functional outcomes. Three hierarchical linear models were used to investigate the relationships of domain-specific neurocognitive trajectories (Memory, Executive function, and Reasoning) with injury severity, demographics, functional outcome at 3 months (Glasgow Outcome Scale-Extended) and emotional distress at 1 year (Symptom Checklist 90-Revised).

RESULTS

Education, injury severity measures, functional outcome, and emotional distress were significantly associated with both Memory and Executive function. Education and emotional distress were related to Reasoning. The interaction effects between time and these predictors in predicting neurocognitive trajectories were nonsignificant. Among patients with data at 1 and 10 year follow-ups (n = 47), 94-96% exhibited stable scores on Executive function and Reasoning tasks, and 83% demonstrated stable scores on Memory tasks. Significant memory decline was presented in 11% of patients.

CONCLUSIONS

The findings highlight the differential contribution of variables in their relationships with long-term neurocognitive functioning after moderate-severe TBI. Injury severity was important for Memory outcomes, whereas emotional distress influenced all neurocognitive domains. Reasoning (intellectual) abilities were relatively robust after TBI. While the majority of patients appeared to be cognitively stable beyond the first year, a small subset demonstrated a significant memory decline over time.

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.

Premorbid functional reserve modulates the effect of rehabilitation in multiple sclerosis

BACKGROUND

Premorbid physically and intellectually enriching lifestyles have increasingly been recognized as able to mitigate the risk of disease-related disability in patients with multiple sclerosis (MS).

OBJECTIVE

To explore if premorbid physical activity, cognitive reserve and trait personality act as proxies for functional reserve that contributes to rehabilitation outcome.

METHODS

We recruited all patients previously enrolled in two pilot trials investigating the effect of home-based video game training in improving balance (Study 1) and attention (Study 2) for additional assessments with the Historical Leisure Activity Questionnaire (HLAQ; a proxy for premorbid physical activity), Cognitive Reserve Index Questionnaire (CRIQ), and Temperament and Character Inventory (TCI). Hierarchical logistic regression (HLR) analyses tested the association of HLAQ, CRIQ, and TCI with training effect on balance (static posturography) and on attention (Symbol Digit Modalities Test).

RESULTS

We identified 94% (34/36) and 74% (26/35) of patients participating at the original Study 1 and Study 2, respectively. HLR analyses showed an exclusive "intra-modal" modulation of rehabilitation outcome by functional reserve, given that (1) larger training effect on balance was associated with higher HLAQ (OR = 2.03, p = 0.031); (2) larger training effect on attention was associated with higher CRIQ (OR = 1.27, p = 0.033). Furthermore, we found specific personality traits associated with (1) greater training effect on balance (self-directedness; OR = 1.40, p = 0.051) and lower training effect on attention (harm avoidance; OR = 0.66, p = 0.075).

CONCLUSION

We hypothesize that premorbid physical and intellectual activities not only act as a buffer for limiting the MS-related damage but also as functional reserve that can be retrieved by task-oriented training to promote recovery through rehabilitation.

Cardiovascular Risk Factors and Brain Health: Impact on Long-Range Cortical Connections and Cognitive Performance

Background Cardiovascular risk factor burden in the absence of clinical or radiological "events" is associated with mild cognitive impairment. Magnetic resonance imaging techniques exploring the integrity of neuronal fiber connectivity within white matter networks supporting cognitive processing could be used to measure the impact of cardiovascular disease on brain health and be used beyond bedside neuropsychological tests to detect subclinical changes and select or stratify participants for entry into clinical trials. Methods and Results We assessed the relationship between verbal IQ and brain network integrity and the effect of cardiovascular risk factors on network integrity by constructing whole-brain structural connectomes from magnetic resonance imaging diffusion images (N=60) from people with various degrees of cardiovascular risk factor burden. We measured axonal integrity by calculating network density and determined the effect of fiber loss on network topology and efficiency, using graph theory. Multivariate analyses were used to evaluate the relationship between cardiovascular risk factor burden, physical activity, age, education, white matter integrity, and verbal IQ . Reduced network density, resulting from a disproportionate loss of long-range white matter fibers, was associated with white matter network fragmentation ( r=-0.52, P<10^-4), lower global efficiency ( r=0.91, P<10^-20), and decreased verbal IQ (adjusted R²=0.23, P<10^-4). Conclusions Cardiovascular risk factors may mediate negative effects on brain health via loss of energy-dependent long-range white matter fibers, which in turn leads to disruption of the topological organization of the white matter networks, lowered efficiency, and reduced cognitive function.

A Positive Relationship between Cognitive Reserve and Cognitive Function after Stroke: Dynamic Proxies Correlate Better than Static Proxies

OBJECTIVES

How brain damage after stroke is related to specific clinical manifestation and recovery is incompletely understood. We studied cognitive reserve (CR) in stroke patients by two types of measurements: (i) objectively verifiable static proxies (i.e., education, occupational attainment), and (ii) subjective, dynamic proxies based on patient testimony in response to a questionnaire. We hypothesized that one or both of these types of CR measurements might correlate positively with patient cognitive performance during the post-acute and chronic phases of recovery.

METHOD

Thirty-four stroke patients underwent neuropsychological assessment at 2, 6 and 24 months after stroke onset. In chronic stage at 24+ months, self-rating assessments of cognitive performance in daily life and social integration were obtained. CR before and after stroke was estimated using static proxies and dynamic proxies were obtained using the Cognitive Reserve Scale (CRS-Pre-stroke, CRS-Post-stroke).

RESULTS

CRS-Pre-stroke and CRS-Post-stroke showed significant mean differences. Dynamic proxies showed positive correlation with self-assessment of attention, metacognition, and functional ability in chronic stage. In contrast, significant correlations between static proxies and cognitive recovery were not found.

CONCLUSIONS

Dynamic proxies of CR were positively correlated with patients' perception of their functional abilities in daily life. To best guide cognitive prognosis and treatment, we propose that dynamic proxies of CR should be included in neuropsychological assessments of patients with brain damage.

Cognitive Reserve Moderates Cognitive Outcome After Mild Traumatic Brain Injury

OBJECTIVE

To investigate whether cognitive reserve moderates differences in cognitive functioning between patients with mild traumatic brain injury (MTBI) and controls without MTBI and to examine whether patients with postconcussion syndrome have lower cognitive functioning than patients without postconcussion syndrome at 2 weeks and 3 months after injury.

DESIGN

Trondheim MTBI follow-up study is a longitudinal controlled cohort study with cognitive assessments 2 weeks and 3 months after injury.

SETTING

Recruitment at a level 1 trauma center and at a general practitioner-run, outpatient clinic.

PARTICIPANTS

Patients with MTBI (n=160) according to the World Health Organization criteria, trauma controls (n=71), and community controls (n=79) (N=310).

MAIN OUTCOME MEASURES

A cognitive composite score was used as outcome measure. The Vocabulary subtest was used as a proxy of cognitive reserve. Postconcussion syndrome diagnosis was assessed at 3 months with the British Columbia Postconcussion Symptom Inventory.

RESULTS

Linear mixed models demonstrated that the effect of vocabulary scores on the cognitive composite scores was larger in patients with MTBI than in community controls at 2 weeks and at 3 months after injury (P=.001). Thus, group differences in the cognitive composite score varied as a function of vocabulary scores, with the biggest differences seen among participants with lower vocabulary scores. There were no significant differences in the cognitive composite score between patients with (n=29) and without (n=131) postconcussion syndrome at 2 weeks or 3 months after injury.

CONCLUSION

Cognitive reserve, but not postconcussion syndrome, was associated with cognitive outcome after MTBI. This supports the cognitive reserve hypothesis in the MTBI context and suggests that persons with low cognitive reserve are more vulnerable to reduced cognitive functioning if they sustain an MTBI.

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.

Predicting mood outcome following traumatic brain injury (TBI): PTA & demographic variables

Background and aims:

Mood disturbance is frequent after traumatic brain injury (TBI), often assessed using the Hospital Anxiety and Depression Scale (HADS). Research supports a three-factor HADS structure (anxiety, depression, and psychomotor), although this has not been used to investigate demographic variables and mood outcome post-TBI. This study examined severity of TBI, demographic variables [age, gender, estimated premorbid IQ (EIQ), relationship status, employment status, socio-economic status (SES)], and mood outcome, using HADS factor scores from a large adult population sample in Tasmania.

Method:

HADS factor scores were calculated for an initial sample of 596 adults. The sample sizes varied according to those attending at 1, 6, 12 and 24 months post-TBI and the available data for each dependent variable.

Results:

Significantly higher anxiety, depression, and psychomotor scores were reported at most follow-ups by females, the middle-aged, and those with lower IQs. Longer post-traumatic amnesia (PTA) was associated with significantly greater mood problems. Occasional significant findings at earlier follow-ups for the factors were noted for those unemployed. Other variables were rarely significant. PTA, premorbid IQ, and Age were included in most Multiple Regression equations predicting outcome for the factors, with Gender included for Anxiety and depression at 6 months after injury.

Conclusions:

Key demographic variables and PTA severity relate to mood post-TBI, and contribute to predicting mood outcome. Differences in findings for the three factors support their use in clinical practice.

The Influence of Cognitive Reserve on Recovery from Traumatic Brain Injury

Objective

we sought to determine the degree to which cognitive reserve, as assessed by the Test of Premorbid Functioning in combination with demographic variables, could act as a buffer against the effect of traumatic brain injury (TBI) on cognitive test performance.

Method

retrospective analysis of a cohort of 121 persons with TBI who completed the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) within 1-12 months after injury.

Results

regression analyses indicated that cognitive reserve was a statistically significant predictor of all postinjury WAIS-IV factor index scores, after controlling for various premorbid and comorbid confounding variables. Only for Processing Speed did injury severity make an additional statistically significant contribution to the prediction model.

Conclusions

cognitive reserve has a protective effect with regard to the impact of TBI on cognitive test performance but this effect is imperfect and does not completely negate the effect of injury severity.

Effect of Cognitive Reserve on Children With Traumatic Brain Injury

OBJECTIVES

Traumatic brain injury can result in cognitive impairments in children. The objective of this retrospective study was to determine to what extent such outcomes are moderated by cognitive reserve, as indexed by parental education.

METHODS

Sixty 6- to 16-year-old children completed the Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V) within 30-360 days after having sustained a traumatic brain injury (TBI). Their Full-Scale IQ and factor index scores were compared to those of demographically matched controls. In addition, regression analysis was used to investigate in the TBI group the influence of injury severity in addition to parental education on WISC-V factor index scores.

RESULTS

Cognitive reserve moderated the effect of TBI on WISC-V Full Scale IQ, Verbal Comprehension, and Visual Spatial. In the TBI group, it also had a protective effect with regard to performance on the Verbal Comprehension, Visual Spatial, and Fluid Reasoning indices. At the same time, greater injury severity was predictive of lower Visual Spatial and Processing Speed index scores in the TBI group.

CONCLUSIONS

Cognitive reserve as reflected in parental education has a moderating effect with regard to children's performance on the WISC-V after TBI, such that higher cognitive reserve is associated with greater preservation of acquired word knowledge and understanding of visual relationships. Measures that emphasize speed of processing remain affected by severity of TBI, even after accounting for the protective effect associated with cognitive reserve. (JINS, 2019, 25, 355-361).