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.     

Neurocognitive fitness in the sub-acute stage after mild TBI: the effect of age

Objective: Age is assumed to be a negative prognostic factor in recovery from moderate-to-severe traumatic brain injury (TBI). Little is known on cognitive performance after mild TBI in relation to age in the sub-acute stage after injury.

Method: Ninety-nine mild TBI subjects (age 15-75) were compared with 91 healthy control subjects (age 14-74) in a case-control design. Patients were matched on age, sex and level of education, with control subjects. Mean interval between injury and cognitive assessment was 13 days. Neurocognitive test battery contained tests of verbal memory, selective attention, general speed of information processing and verbal fluency.

Results: An overall effect was found of a single mild TBI on neurocognitive performance in the sub-acute stage after injury. Age did not add significantly to the effect of mild TBI on cognitive functioning.

Conclusion: Patients suffering from mild TBI are characterized by subtle neurocognitive deficits in the weeks directly following the trauma. The notion that elderly subjects have a worse outcome in the sub-acute period after mild TBI is at least not in line with the results of this study.     

Sustained attention in children and adolescents after traumatic brain injury: relation to severity of injury, adaptive functioning, ADHD and social background

Primary objective: To examine the relationship of child and family psychosocial variables and traumatic brain injury (TBI) severity as it relates to sustained attention (the Paediatric Assessment of Cognitive Efficiency, PACE).

Research design: Forty-two children and adolescents were recruited and participated in a 2 year longitudinal study to evaluate sustained attention using the computerized testing metric, PACE. More specifically, errors of omission (inattention) and commission (impulsiveness) were measured.

Main outcomes and results: Significant improvement on inattention and impulsiveness were observed over time. High pre-injury psychosocial adversity and low pre-injury adaptive functioning significantly predicted a greater number of inattention errors. Severity of injury predicted the reduction of impulsiveness. Moreover, omission errors immediately after TBI predicted later secondary attention-deficit/hyperactivity disorder (SADHD, ADHD that emerges after TBI).

Conclusions: Based on these findings, it is important to consider pre-injury child and family psychosocial characteristics in addition to severity of injury when predicting outcome of TBI in children.     

Cognitive appraisal accuracy moderates the relationship between injury severity and psychosocial outcomes in traumatic brain injury

Objective:Traumatic brain injury (TBI) frequently results in significant changes in physical, cognitive and emotional status. Outcomes after TBI may be related to accurate appraisal of these changes. This study examined the relationship between cognitive appraisal accuracy and psychosocial outcomes in TBI survivors.

Methods: Participants were male and female TBI survivors (n = 103) who were at least 6 months post-injury and a family member of each survivor. Appraisal accuracy was assessed using self- and observer-report measures of perceived cognitive difficulties. Family members also completed a measure of psychosocial function. Hierarchical regression techniques were used to determine whether cognitive appraisal accuracy accounted for a significant proportion of variance in psychosocial outcomes.

Results:Study findingsindicated cognitive appraisal accuracy moderated the relationship between injury severity and aspects of psychosocial function.

Conclusions:The results suggest that brain injury outcomes may be improved when an individual is able to accurately assess limitations.     

Factors triggering relatives' judgements of personality change after traumatic brain injury

Objective: This study assesses neuropsychological and psychosocial determinants of judgements of personality change (PC) after traumatic brain injury (TBI).

Design: Cross-sectional data from 87 participants with TBI analysed using hierarchical binary regression.

Methods: Interview of participants assessed, injury severity (post-traumatic amnesia), degree of cognitive impairment (IQ and memory), presence of orbitofrontal and/or medial temporal damage (olfaction) and emotional reactions (anger, depression and anxiety questionnaires). Separate interview of relatives assessed their own response to the injury (emotional reactions and critical comments from the Expressed Emotion index) and their judgements of participants' behavioural change.

Results: As expected, memory loss and impaired olfaction predicted relatives' PC judgements. However, the most striking and novel result was that social-emotional factors (participants' and relatives' reactions) predicted PC judgements best.

Conclusions: This study emphasizes the need (a) for future studies measuring social behaviours (e.g. impulsivity and emotional perception) (b) to explore the differing determinants of relatives' and participants' PC judgements and (c) to develop and to tailor clinical responses to the various psychosocial determinants of PC.     

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.     

Who benefits? Outcome following a coping skills group intervention for traumatically brain injured individuals

Primary objective: To investigate the variables associated with positive psychological outcome following a group intervention for 33 individuals with traumatic brain injury.

Research design: Evaluation study which used multiple regression analysis to examine the variables associated with change in psychological adjustment following a 10-session cognitive behaviour therapy-based group.

Methods and procedures: The predictor variables were age at injury, time since injury, injury severity, self-awareness, pre-morbid intellectual function, memory function, executive function and level of depression and anxiety prior to intervention.

Main outcomes and results: The predictor variables contributed a significant proportion of the variance in percentage change in depression. The major finding was that better outcomes following intervention were associated with greater self-awareness of injury-related deficits.

Conclusions: The present study identified a number of variables that were associated with improvement in depression following psychological intervention and may assist future treatment resources to be directed most effectively.     

Applicability of neural reserve theory in mild traumatic brain injury

Objective: The aim of the current study was to examine whether neural reserve influenced the duration of post-traumatic amnesia (PTA) following mild traumatic brain injury (MTBI).

Method: The relationship between duration of PTA and both IQ and education was examined in a group of 59 MTBI patients. In addition, the effects of factors that could potentially diminish neural reserve, namely pre-injury hazardous alcohol consumption, pre-injury marijuana use, previous neurological damage, age and post-injury emotional distress on PTA duration were analysed.

Results: Significant, negative associations between PTA duration and both IQ and education were revealed. None of the other variables that were examined were significantly related to PTA duration.

Conclusion: The findings were interpreted as providing preliminary evidence to suggest that reference to neural reserve may help explain between-subject variability in acute response to MTBI.     

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.     

Utility of Glasgow Coma Scale-Extended in symptom prediction following mild traumatic brain injury

Study objective: To examine the efficacy of the Glasgow Coma Scale-Extended (GCS-E) for the prediction of symptoms commonly associated with mild traumatic brain injury (TBI).

Method: Three hundred and sixty-one participants with a mild TBI were evaluated using the GCS-E and the Standardized Assessment of Concussion. A sub-group of 185 participants took part in a more extensive evaluation, which also included measures of depression and vestibular symptoms. All participants had a Glasgow Coma Scale score of 15, but experienced varying lengths of post-traumatic amnesia (PTA) as measured by the GCS-E.

Results: Use of the GCS-E for assessment of PTA duration revealed that longer lengths of amnesia following mild TBI were associated with greater incidence of dizziness, depression and cognitive impairments during the first weeks after injury.

Conclusion: Results suggest that the GCS-E is a useful tool for the prediction of symptoms associated with mild TBI.     

The impact of acute care medications on rehabilitation outcome after traumatic brain injury

Objectives: To examine the impact of medications with known central nervous system (CNS) mechanisms of action, given during the acute care stages after traumatic brain injury (TBI), on the extent of cognitive and motor recovery during inpatient rehabilitation.

Design: Retrospective extraction of data utilizing an inception cohort of moderate and severe TBI survivors.

Methods: The records of 182 consecutive moderate and severe TBI survivors admitted to a single, large, Midwestern level I trauma centre and subsequently transferred for acute inpatient rehabilitation were abstracted for the presence of 11 categories of medication, three measures of injury severity (worst 24 hour Glasgow Coma Scale, worst pupillary response, intra-cranial hypertension), three measures of outcome (Function Independence Measure (FIM) Motor and Cognitive scores at both rehabilitation admission and discharge and duration of post-traumatic amnesia (PTA)).

Main outcome and results: The narcotics, benzodiazepines and neuroleptics were the most common categories of CNS active medications (92%, 67% and 43%, respectively). The three categories of medications appeared to have no significant outcome on the FIM outcome variables. The neuroleptics affected cognitive recovery with almost 7 more days required to clear PTA in the neuroleptic treated group. The presence of benzodiazepines did tend to obscure the impact of neuroleptics on PTA duration but the negative impact of neuroleptics on PTA duration remained significant.

Conclusions: The results suggest that the use of neuroleptics during the acute care stage of recovery has a negative impact on recovery of cognitive function at discharge from inpatient rehabilitation. Due to the paucity of subjects with hemiplegia in this cohort, conclusions could not be drawn as to the impact of acute care medications on motor recovery.     

Comparison of functional outcome following acute care in young, middle-aged and elderly patients with traumatic brain injury

Primary objective: To compare functional physical and cognitive outcome of patients in three age groups with mild, moderate and severe traumatic brain injury (TBI) at discharge from acute care.

Research design: Retrospective database review.

Methods and procedures: Scores on the Extended Glasgow Outcome Scale (GOSE) and on the FIM™ instrument,1 discharge destination and length-of-stay (LOS) were gathered and compared for 2327 patients with TBI admitted to a level 1 trauma hospital from 1997-2003 divided into three age groups; 971 patients between 18-39 years, 672 between 40-59 years and 684 aged 60-99 years.

Main outcomes and results: Relative to younger adults with similar TBI severity, elderly patients showed worse outcome on the GOSE and FIM™ instrument (physical and cognitive ratings) and longer LOS. No difference was observed between the young and middle-aged groups except for cognitive FIM™ ratings and LOS for severe TBI. A higher percentage of elderly patients went to in-patient rehabilitation, to long-term care facilities or died compared to young and middle-aged patients. A higher number of young and middle-aged patients were discharged home.

Conclusions: Further development of services in early rehabilitation as well as post-rehabilitation geared to the specific needs of the elderly patient with TBI is required as the population ages.     

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.     

Return to work following moderate-to-severe traumatic brain injury

Primary objective: To investigate the role of cognitive functioning, fatigue, mood and behaviour in return to work (RTW) following moderate-to-severe traumatic brain injury.

Design and methods: Between-groups comparisons were conducted with 20 participants who had RTW and 13 who had not. Participants were well matched for age, pre-morbid intellectual functioning, years of education, injury severity and time since injury.

Outcomes and results: The unemployed group reported significantly higher levels of fatigue and depression and significantly more problems on self-report questionnaires. A significantly higher proportion of this group was seeking compensation. No significant differences were obtained on neuropsychological measures of cognitive functioning.

Conclusions: Mood, fatigue and behavioural problems may impede a person's ability to RTW. Subjective measures may be more superior to objective measures in predicting RTW. The litigation process may affect people's motivation to RTW.     

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.     

Psychosocial outcomes 1-7 years after comprehensive milieu-oriented neurorehabilitation: the role of pre-injury status

Primary objective: To explore pre-injury variables related to post-discharge psychosocial status and identify factors related to work and driving outcomes.

Methods and procedures: Ninety-three brain-injured patients attended a holistic milieu-oriented neurorehabilitation program and were contacted 1-7 years post-discharge.

Experimental interventions: Questionnaire data addressing pre-injury and post-injury work, driving, income, marital status and living situation.

Main outcomes and results: 74.3% were involved in competitive work and/or school with 86.0% productive at follow-up. Post-injury income decreased significantly compared with pre-injury levels. Pre-injury relationship status did not differ significantly from post-injury; 81.1% remaining in a stable relationship or married at follow-up. Pre-injury and post-injury accident rates were related; 73.1% drove at follow-up. Higher education, non-right hemispheric injury, shorter treatment length and return to work related to driving. Younger age, higher education, non-right hemispheric injury and driving post-injury related to positive work status.

Conclusions: Pre-injury psychosocial data provide an important context for understanding post-discharge outcome after brain injury. Holistic milieu-oriented rehabilitation facilitates long-term successful work, driving and relationship stability.     

Psychiatric risk factors for traumatic brain injury

Objective: To examine the risk of sustaining a traumatic brain injury (TBI) associated with prior psychiatric conditions beyond that of fixed demographic variables.

Design: Retrospective cohort study of non-referred community-dwelling male US veterans.

Methods: Two-hundred and seventy-one individuals who sustained a TBI with altered consciousness were compared with 630 controls without a history of head injury, selected from a larger sample of 3766.

Results: Hierarchical logistic regression analyses were used to model odds ratios and 95% confidence intervals for the unique association between pre-existing psychiatric disorders and the likelihood of incurring a TBI while adjusting for demographic characteristics and other known predictor variables. Mood (odds ratio 2.48, 95% confidence interval 1.23-5.01), anxiety (OR 1.64, 95% CI 1.01-2.68) and conduct disorders (OR 1.66, 95% CI 1.16-2.38) increased the risk of head injury.

Conclusions: The pre-existence of psychiatric illness, particularly depression, anxiety and conduct disorder, increased the future risk of incurring a TBI. The implementation of early identification and treatment of psychiatric conditions may potentially lower risk and reduce yearly incidence rates of TBI.     

Neuropsychiatric correlates of traumatic brain injury (TBI) among Australian prison entrants

Primary objective: To investigate the association between reported past traumatic brain injury (TBI) and demographic, neuropsychiatric and criminographic parameters among individuals recently received into custody.

Research design: A random sample of men recently received into the New South Wales (Australia) criminal justice system were screened for a history of TBI and the details of up to five separate TBI episodes were obtained. We also screened for depression, psychosis, personality disorder, drug and alcohol use, and 'social connectedness'.

Main outcome and results: Among the 200 study participants, 82% reported past TBI. TBI was associated with a history of engagement in contact sports, school expulsion, daily illicit drug use, depression and psychosis.

Conclusions: Past TBI is common among prisoners entering the criminal justice system and, amongst other correlates, appears to be highly associated with increased rates of major mental illness.     

The characteristics of patients who do not seek medical treatment for traumatic brain injury

Primary objective: To identify factors associated with not seeking medical care for traumatic brain injury (TBI).

Research Design: Internet survey.

Methods and procedures: The survey consisted of 17 questions related to demographics, TBI case ascertainment, location and mechanism of injury, type of treatment sought, and post-concussive (PC) symptoms. Logistic regression was used to identify factors associated with not seeking medical care.

Main outcome and results: Of the 1381 survey respondents with TBI, 584 (42%) did not seek medical care. TBI respondents were less likely to seek care if they were older (OR 0.98, 95% CI 0.97-0.99), suffered a mild TBI grade 2/3 (OR 0.42, 95% CI 0.31-0.58), or were injured in the home (OR 0.53, 95% CI 0.36-0.78).

Conclusions: Several factors associated with not seeking medical care after TBI were identified. Raising public awareness of the signs and symptoms of TBI, and the benefits of medical care, could help increase the number of TBI patients who seek medical care.