Memory outcome at 5 years post-childhood traumatic brain injury

PRIMARY OBJECTIVE: This study seeks to extend previous findings by documenting memory performance in a sample of 70 children at 5 years post-injury. It was anticipated that increasing injury severity would be associated with decreased performance on working and complex memory tasks. It was also expected that injury severity would significantly predict memory, but that the time from insult to subsequent testing would be associated with an increased relationship to non-injury factors. RESEARCH DESIGN: Participants were assessed at 5 years post-injury, aged between 6-14 years, using measures of immediate, working and complex memory. METHODS AND PROCEDURES: The sample comprised 18 children who had sustained a severe TBI, 24 with a moderate TBI, 11 with a mild TBI and 17 healthy controls, matched for age, gender and socio-economic-status. RESULTS: Results indicated that severe TBI was associated with decreased complex auditory-verbal memory performance, although children with TBI did not display impairment on immediate, working or complex visual-spatial memory. While injury severity significantly predicted complex memory outcome, non-injury factors failed to significantly predict either working or complex memory performance. CONCLUSIONS: Future research should be engineered towards further clarifying what influences recovery from childhood TBI in the elongated post-injury period.     

Recovery in memory function in the first year following TBI in children

Primary objective : To examine memory skills, at acute, 6- and 12-monthly stages, following childhood traumatic brain injury (TBI).

Research design : Prospective, longitudinal, between-group design, comparing pre-injury and postinjury intellectual and memory measures, across three levels of injury severity.

Methods and procedures : Investigation of memory skills in a group of 76 children who had sustained a mild, moderate or severe TBI. Specific tests were used to measure immediate and short-term memory, and more complex multi-trial learning.

Main outcomes and results : The severe TBI group exhibited greater deficits on memory tasks, irrespective of modality, in the acute, 6- and 12-month post-injury stages, in comparison to mild and moderate TBI groups. Performance was dependent on both injury severity and task demands.

Conclusions : Memory difficulties are present during the acute, 6- and 12-months following childhood TBI. With a clearer understanding of the memory deficits following TBI, appropriate strategies can be taught and interventions implemented for these children.     

Central executive system impairment in traumatic brain injury

Primary objective: This study investigated whether cognitive impairment after traumatic brain injury (TBI) can be considered a consequence of (1) a speed processing deficit or (2) an impairment of the Central Executive System (CES) of working memory.

Methods and procedures: Thirty-seven TBI patients underwent a standardized battery of neuropsychological tests evaluating speed processing, sustained attention, short-term memory, working memory, divided attention, executive functions and long-term memory.

Main outcomes and results: Patients showed severe deficits in working memory, divided attention, executive functions and long-term memory. Divided attention, long-term memory and executive functions deficits significantly correlated with working memory, but not with speed processing deficits. Moreover, multiple regression analyses showed that a CES impairment and not a speed processing deficit predicted divided attention, executive functions and long-term memory deficits. The severity and the site of brain lesions did not predict the level of CES or speed processing impairment.

Conclusions: The cognitive impairment following TBI seem to be caused by an impairment of the Central Executive System, rather than a speed processing deficit.     

Gender and traumatic brain injury: do the sexes fare differently?

Objective: To examine the relationship between gender and cognitive recovery 1 year following traumatic brain injury (TBI).

Methods: Patients with blunt TBI were identified from the TBI Model Systems of Care National Database, multi-centre cohort study. The included patients (n = 325) were 16-45 years at injury, admitted to an acute care facility within 24 hours, received inpatient rehabilitation, had documented admission Glasgow Coma Scale (GCS) scores, completed neuropsychological follow-up 1 year post-injury and did not report pre-morbid learning problems. Multivariate analyses of variance examined the unadjusted association between gender and six cognitive domains examining attention/working memory, verbal memory, language, visual analytic skills, problem-solving and motor functioning. Analyses of covariance models were constructed to determine if confounding factors biased the observed associations.

Results: Females performed significantly better than males on tests of attention/working memory and language. Males outperformed females in visual analytic skills. Gender remained significantly associated with performance in these areas when controlling for confounding variables.

Conclusions: These results suggest a better cognitive recovery of females than males following TBI. However, future studies need to include non-TBI patients to control for possible pre-injury gender-related differences, as well as to conduct extended follow-ups to determine the stability of the observed differences.     

Computed tomography findings and early cognitive outcome after traumatic brain injury

Primary objective: To examine the relationship between CT abnormalities and early neuropsychological outcome following traumatic brain injury (TBI) using quantitative CT analyses, data reduction methods for neuropsychological results and specific hypotheses based on literature review.

Research design: Observational, prospective cohort study using acute (emergency) CT data and neuropsychological test data from 89 participants with TBI who were hospitalized for rehabilitation.

Methods and procedures: Principal components analysis with varimax rotation was used to reduce data from a standard battery of eight neuropsychological tests administered after clearance of post-traumatic amnesia (1 month post-TBI on average). Bivariate correlations were used to examine relationships of three factors (verbal memory, cognitive processing speed and verbal working memory) to quantitative volumetric analysis of CT scan abnormalities (size, number and location). Specific hypotheses as to CT predictors of poor performance on each factor were tested using multivariable linear regression that included injury severity and demographic variables.

Main results: Eighty-nine per cent of participants had some pathology on initial CT. Age, education and time to follow commands (TFC), an index of overall injury severity, were significantly associated with the neuropsychological factors. However, none of the specific hypotheses about CT scan variables and cognitive outcome were strongly supported by the data. There was a trend for any CT abnormality to predict slower speed of processing and for higher number of brain lesions to predict worse memory performance.

Conclusions: Despite the precision added by quantitative CT analysis, CT findings did not improve on demographic factors and TFC in predicting early cognitive outcome of TBI. Imaging methods that are more sensitive to white matter integrity may be needed to develop pathophysiologic predictors of TBI outcome.     

Parental concerns and distress after paediatric traumatic brain injury: a qualitative study

Objective: To determine concerns of parents associated with high distress levels in the care of children with traumatic brain injury (TBI).

Setting and participants: Primary care hospital/medical centre-based study on parental perspectives following TBI in school age children (n = 100; 19 orthopaedic trauma controls and 81 children with a history of TBI).

Main outcome measures: Verbatim reports regarding major concerns on the Child Behaviour Checklist (CBCL), as well as parental ratings regarding their overall distress level when caring for the child.

Results: Summary of verbatim comments indicated that parents who report high levels of distress in the care of their children were specifically concerned about the child's poor school performance, lack of friends, inability to control angry feelings and apathy. Fear of the future consequences of the TBI was also cited as a major concern. Parent ratings of distress level was significantly, but weakly correlated with the severity of TBI in their children (r = +0.26, n = 94, p = 0.01).

Conclusion: Reports of severe distress in the care of TBI children by parents are seen at all levels of severity of TBI. Addressing these parental concerns may increase parental engagement in the rehabilitation process.     

The relationship between working memory, processing speed, verbal comprehension and FAS performance following traumatic brain injury

Primary objective: To investigate the relationship of working memory, processing speed and verbal comprehension with FAS performance in individuals who had sustained a traumatic brain injury (TBI).

Methods and procedure: Sixty-three patients with a TBI were grouped according to the presence of impaired verbal fluency performance and then compared on a number of cognitive and demographic variables.

Results: Following a TBI, working memory and processing speed had the greatest influence on verbal fluency performance. For those individuals who have not sustained a TBI, education, verbal intelligence, working memory and speed of information processing were related to FAS performance.

Conclusions: The findings of the study indicate that FAS performance was related to verbal intelligence, working memory ability, attention and speed of information processing. The results further suggest that different variables are related to FAS performance following a TBI as compared with control group performances.     

Neuropsychological function 23 years after mild traumatic brain injury: a comparison of outcome after paediatric and adult head injuries

Primary objective: To the authors' knowledge no study comparing very long-term neuropsychological outcome after mild paediatric and adult traumatic brain injury (TBI) has been published. The primary objective of this study was to compare neuropsychological outcome 23 years after mainly mild paediatric and adult TBI.

Research design: The study was a neuropsychological follow-up 23 years after a prospective head injury study conducted at a Norwegian public hospital.

Methods and procedures: One hundred and nineteen patients were assessed with a comprehensive neuropsychological test battery. Of these, 45 were paediatric TBI and 74 were adult TBI.

Main outcomes and results: Both the paediatric and adult groups obtained scores in the normal range. In the paediatric group significant relationships were found between head injury severity and current neuropsychological function. The most important predictors of poor outcome were length of post-traumatic amnesia (PTA) and a combination of PTA and EEG pathology within 24 hours of injury. No influence of pre- and post-injury risk factors on current neuropsychological function was evident.

Conclusions: The findings indicate that children sustaining complicated mild TBI may be more vulnerable to development of chronic mild neuropsychological dysfunction than adults sustaining similar head injuries.     

Role of premorbid factors in predicting safe return to driving after severe TBI

Primary objective: The present study explored the possibility of predicting post-injury fitness to safe driving in patients with severe traumatic brain injury (TBI) (n = 66).

Methods and procedure: Sixteen different measures, derived from four domains (demo/biographic, medico-functional, neuropsychological, and psychosocial) were used as predictor variables, whereas driving outcomes were assessed in terms of driving status (post-TBI drivers versus non-drivers) and driving safety (number of post-TBI car accidents and violations).

Main outcomes and results: About 50% of the patients resumed driving after TBI. Compared to post-TBI non-drivers, post-injury drivers had shorter coma duration. With regard to driving safety, the final multiple regression model combined four predictors (years post-injury, accidents and violations before TBI, pre-TBI-risky-personality-index, and pre-TBI-risky-driving-style-index) and explained 72.5% of variance in the outcome measure.

Conclusions: Since the best three predictors of post-injury driving safety addressed patients' premorbid factors, the results suggest that in order to evaluate the actual possibility of safe driving after TBI, it would be advisable to consider carefully patients' pre-TBI histories.     

Behaviour and school performance after brain injury

Primary objective: To examine the relationship between behavioural problems and school performance following traumatic brain injury (TBI).

Methods and procedures: Subjects: 67 school-age children with TBI (35 mild, 13 moderate, 19 severe) and 14 uninjured matched controls. Parents and children were interviewed at a mean of 2 years post-TBI. Teachers reported on academic performance and educational needs. Children were assessed using the Vineland Adaptive Behaviour Scales (VABS) and the Weschler Intelligence Scale for Children (WISC-III).

Main outcomes and results: Two-thirds of children with TBI exhibited significant behavioural problems, significantly more than controls (p = 0.02). Children with behavioural problems had a mean IQ ∼ 15 points lower than those without (p = 0.001, 95% CI: 7-26.7). At school, 76%(19) of children with behavioural problems also had difficulties with schoolwork. Behavioural problems were associated with social deprivation and parental marital status (p ≤ 0.01).

Conclusions: Children with TBI are at risk of developing behavioural problems which may affect school performance. Children with TBI should be screened to identify significant behavioural problems before they return to school.     

Being restricted in participation after a traumatic brain injury is negatively associated by passive coping style of the caregiver

Purpose: To examine whether the caregivers' coping style is associated with the functional outcome of the traumatic brain injury (TBI) patient 1 year post-injury.

Method: A cross-sectional study among patients with a TBI, including their primary caregivers. The study included 51 patients aged 17-64 years with a moderate-to-severe TBI and 51 caregivers (23 parents and 28 partners) aged 23-67 years. The coping preferences of the caregivers were assessed at minimum 6 and maximum 12 months post-injury, by filling out the Utrecht Coping List (UCL) and were related to limitations in activity, as measured with the Frenchay Activities Index and with restrictions in participation as measured with the Sickness Impact Profile-68 of TBI patients 1 year post-injury. The patients were interviewed at their homes; the caregivers received and returned the UCL by mail.

Results: The patients' age and the caregivers' coping style are independently associated with restrictions in participation 1 year post-injury.

Conclusions: A passive coping style of the primary caregiver is negatively associated with the patient's functional outcome in terms of participation in society.     

Working memory and proverb comprehension in adolescents with traumatic brain injury: a preliminary investigation

Primary objective: This study investigated the relationship between working memory and comprehension of low-familiarity proverbs in adolescents with traumatic brain injury (TBI).

Methods and procedures: Ten adolescents, aged 12-21 years who had suffered a TBI prior to the age of 10 years and 10 individually age-matched peers with typical development participated in the study. The participants listened to short paragraphs containing a proverb and interpreted the meaning of the proverb using a forced-choice task. In addition, participants engaged in a task that evaluated working memory ability. Main outcomes and results: Analysis revealed that individuals with TBI differed from their non-injured peers in their understanding of proverbs. In addition, working memory capacity influenced performance for all participants.

Conclusions: The importance of considering working memory when evaluating figurative language comprehension in adolescents with TBI is highlighted. Implications for future research, particularly with regard to varying working memory and task demands, are considered.     

Children's brain injury: a postal follow-up of 525 children from one health region in the UK

Primary objectives : To follow-up a population of children admitted to one Hospital Trust with traumatic brain injury (TBI), and compare outcomes following mild TBI with outcomes following moderate or severe TBI.

Research design : Population-based postal questionnaire survey.

Methods and procedures : Questionnaires were mailed to parents of all 974 surviving children on a register of paediatric TBI admissions, 525 completed questionnaires were returned (56.2%). Most children (419) had suffered mild TBI, 57 moderate, and 49 severe.

Main outcomes and results : Thirty per cent of parents received no information on post-injury symptoms, and clinical follow-up was limited. Statistically significant differences were observed between mild and moderate/severe groups for cognitive, social, emotional, and mobility problems. Nevertheless, ~20% of the mild group suffered from poor concentration, personality change and educational problems post-injury. Few schools (20%) made special provision for children returning after injury.

Conclusions : Children can have long-lasting and wide-ranging sequelae following TBI. Information should be routinely given to parents and schools after brain injury.     

Traumatic brain injury and functional outcomes: does minority status matter?

Objectives: (1) to determine differences between minorities vs. non-minorities on demographic, injury and rehabilitation characteristics and functional outcomes at admission, discharge and 1-year post-injury and (2) to examine differences in functional outcome at 1-year post-injury among (African-Americans, Hispanics and Whites).

Design: Retrospective study.

Setting: Longitudinal data were extracted from the TBI Model Systems database.

Participants: 4929 individuals with moderate-to-severe TBI (3354 Whites vs. 1575 Minorities: 1207 African-Americans and 368 Hispanics) hospitalized between 1989-2004.

Main outcome measures: Functional outcomes at 1-year post-injury (Disability Rating Scale, Functional Independence Measure, Glasgow Outcome Scale-Extended and Community Integration Questionnaire).

Results: At discharge and 1-year post-injury, minorities had poorer functional outcomes compared with Caucasians on all measures. After controlling for sociodemographic, injury and functional characteristics at admission, Hispanics and African-Americans still showed worse functional outcomes at 1-year post-injury compared with Whites on the DRS, FIM and CIQ. There were no significant differences between African Americans and Hispanics.

Conclusions: Minorities had significantly reduced long-term functional outcome after rehabilitation relative to Whites. It is imperative that rehabilitation professionals' consider factors related to poorer long-term functional outcome and work to improve the quality of life of minorities with TBI.     

Recognition of emotion from facial expression following traumatic brain injury

Primary Objective: To assess three domains of emotion recognition in people with traumatic brain injury (TBI).

Research design: A between group comparison.

Procedures: Twenty-four participants with severe TBI and 15 matched participants without brain damage were asked to label and match facial expressions with and without context. The participants with TBI were also interviewed regarding changes in subjective experience of emotion.

Main outcomes and results: Participants with TBI were found to be significantly impaired on expression labelling and matching, but experienced some improvement when provided with context. Negative emotions were particularly affected. Affective semantic knowledge and face perception appeared to be relatively intact in this group. The majority of participants with TBI reported some change in the post-injury experience of everyday emotion, although the pattern of changes differed greatly between individuals. Reduced subjective experience, especially of sadness and fear, was associated with poor emotion matching but not emotion labelling.     

Theory of mind in children with traumatic brain injury

Objective: This study was designed to examine the existence of deficits in mentalizing or theory of mind (ToM) in children with traumatic brain injury (TBI).

Research design: ToM functioning was assessed in 12 children aged 6-12 years with TBI and documented frontal lobe damage and compared to 12 controls matched for age, sex and verbal ability. Brief measures of attention and memory were also included.

Main outcome and results: The TBI group was significantly impaired relative to controls on the advanced ToM measure and a measure of basic emotion recognition. No difference was found in a basic measure of ToM.

Conclusion: Traumatic brain damage in childhood may disrupt the developmental acquisition of emotion recognition and advanced ToM skills. The clinical and theoretical importance of these findings is discussed and the implications for the assessment and treatment of children who have experienced TBI are outlined.     

Long-term neuropsychological performance in a cohort of children and adolescents after severe paediatric traumatic brain injury

Objective: The purpose of the present study was to evaluate progress in neuropsychological performance in children and adolescents with severe paediatric traumatic brain injury (TBI), from admission to the rehabilitation centre up to 3-12 years after the trauma.

Methods: Children and adolescents (n = 31, mean age at injury 11.8 years, SD = 3.8; at follow-up 18.8 years; SD = 4.5) who all had suffered a TBI participated. A comprehensive neuropsychological test battery was administered at the start of rehabilitation (T1), around discharge (T2) and in the long-term (at least 3 years after rehabilitation; T3). T1 and T2 were clinical assessments; T3 was executed as a follow-up measurement for this study.

Results: At T1 and T2, most problems were in the domains of attention, memory and executive functioning. At the start of rehabilitation most deficits were with performal intelligence (61%); at discharge (mean length of stay 411 days) considerably less children had severe deficits on the intelligence domain (23%). At long-term follow-up, most problems were in the domains attention, mental speed and memory. From admission to discharge 42% of the children improved on two or more cognitive tests; from discharge to follow-up this percentage was 13%.

Conclusions: In this unique study a clinical cohort of children with severe TBI was followed for many years after injury. Most cognitive deficits were found in the early phase of rehabilitation. Most children did improve on cognitive functioning (40%) during the first year after their injury, whereas at follow-up most children had not changed. At follow-up, more than half of the children (54%) attended a regular school or had a regular job, corresponding to their age and pre-morbid functioning.     

Confirmatory factor structure of the Center for Epidemiologic Studies-Depression scale (CES-D) in mild-to-moderate traumatic brain injury

Primary objective: The Center for Epidemiologic Studies Depression scale (CES-D) is a frequently-used self-report measure of depressive symptom severity. Brief depression screening measures can be important in the identification and prediction of depression following traumatic brain injury. The objective of this study was to investigate the validity of the CES-D in measuring depressive symptoms in patients with mild-to-moderate TBI as it has been rarely used in neurologically compromised populations.

Research design: Inception cohort.

Methods and procedures: The CES-D was administered to 340 participants with mild-to-moderate TBI at 3-months post-injury.

Main outcomes and results: Confirmatory factor analysis of the CES-D indicated that the data are a reasonable fit similar to that of Radloff 's original 4-factor model.

Conclusions: These findings suggest that the CES-D may be appropriate for use in patients with mild-to-moderate TBI.     

Relationship between balance abilities and gait characteristics in children with post-traumatic brain injury

Objectives: To quantify the differences in gait variability and balance performance between typically developed (TD) children and children with post-traumatic brain injury (TBI) and to determine the association between gait variability and functional balance in both groups.

Design: Cross-sectional study.

Setting: Physical therapy department of a paediatric and adolescent rehabilitation hospital.

Participants: A convenience sample of 24 children post-TBI and 24 TD age and sex matched controls.

Intervention: Not applicable.

Main outcome measure: Step length, step time and base width variability measured with an electronic walkway; timed up and go (TUG) test and functional reach test (FRT) as a functional balance test.

Results: Base width and step time variability showed no significant difference between the groups. However, children post-TBI had significantly greater variability in step length in comparison to healthy controls. The functional balance abilities of children post-TBI were significantly limited compared to TD children. A significant linear inverse correlation was found between balance performance and step length variability only among children with a TBI.

Conclusion: Ambulatory children post-severe TBI had decreased balance performance, decreased gait speed and increased step length variability as compared to age-matched healthy controls.