Prediction of the level of cognitive functional independence in acute care following traumatic brain injury

Using machine learning to discover traumatic brain injury patient phenotypes: national concussion surveillance system Pilot

OBJECTIVE

The objective is to determine whether unsupervised machine learning identifies traumatic brain injury (TBI) phenotypes with unique clinical profiles.

METHODS

Pilot self-reported survey data of over 10,000 adults were collected from the Centers for Disease Control and Prevention (CDC)'s National Concussion Surveillance System (NCSS). Respondents who self-reported a head injury in the past 12 months (n = 1,364) were retained and queried for injury, outcome, and clinical characteristics. An unsupervised machine learning algorithm, partitioning around medoids (PAM), that employed Gower's dissimilarity matrix, was used to conduct a cluster analysis.

RESULTS

PAM grouped respondents into five TBI clusters (phenotypes A-E). Phenotype C represented more clinically severe TBIs with a higher prevalence of symptoms and association with worse outcomes. When compared to individuals in Phenotype A, a group with few TBI-related symptoms, individuals in Phenotype C were more likely to undergo medical evaluation (odds ratio [OR] = 9.8, 95% confidence interval[CI] = 5.8-16.6), have symptoms that were not currently resolved or resolved in 8+ days (OR = 10.6, 95%CI = 6.2-18.1), and more likely to report at least moderate impact on social (OR = 54.7, 95%CI = 22.4-133.4) and work (OR = 25.4, 95%CI = 11.2-57.2) functioning.

CONCLUSION

Machine learning can be used to classify patients into unique TBI phenotypes. Further research might examine the utility of such classifications in supporting clinical diagnosis and patient recovery for this complex health condition.

Minimally conscious state plus versus minus: Likelihood of emergence and long-term functional independence

OBJECTIVE

Severe brain injuries can result in disorders of consciousness, such as the Minimally Conscious State (MCS), where individuals display intermittent yet discernible signs of conscious awareness. The varied levels of responsiveness and awareness observed in this state have spurred the progressive delineation of two subgroups within MCS, termed "plus" (MCS+) and "minus" (MCS-). However, the clinical validity of these classifications remains uncertain. This study aimed to investigate and compare the likelihood of emergence from MCS, as well as the functional independence after emergence, in individuals categorized as in MCS+ and MCS-.

METHODS

Demographic and behavioral data of 80 participants, admitted as either in MCS+ (n = 30) or MCS- (n = 50) to a long-term neurorehabilitation unit, were retrospectively analyzed. The neurobehavioral condition of each participant was evaluated weekly until discharge, demise, or emergence from MCS. The functional independence of those participants who emerged from MCS was assessed 6 months after emergence.

RESULTS

While only about half of the individuals classified as in MCS- (n = 24) emerged from the MCS, all those admitted as in MCS+ did, and in a shorter postinjury period. Despite these differences, all individuals who emerged from the MCS demonstrated similar high disability and low functional independence 6 months after emergence, regardless of their state at admission.

INTERPRETATION

Individuals classified as MCS+ exhibited a higher likelihood of emergence and a shorter time to emergence compared to those in MCS-. However, the level of functional independence 6 months after emergence was found to be unrelated to the initial state at admission.

Predictive validity of the Westmead Post-Traumatic Amnesia Scale for functional outcomes in school-aged children who sustained traumatic brain injury

The Westmead Post-Traumatic Amnesia Scale (WPTAS) is routinely used for the assessment of post-traumatic amnesia (PTA) in children who sustained traumatic brain injury (TBI). Yet, the WPTAS' predictive validity for functional outcomes is largely unknown. We aimed to determine whether PTA duration measured by the WPTAS (i) differentially predicts functional outcomes and (ii) contributes to predictions of outcomes beyond the Glasgow Coma Scale (GCS) in children who sustained TBI. Participants were children and adolescents with moderate-to-severe TBI (n = 55) aged 8-15 years. PTA duration was assessed with the WPTAS. Outcomes at the first outpatient follow-up were scored on the Kings Outcome Scale for Childhood Head Injury (KOSCHI) and the TBI Outcome Domain Scale-Extended (ODS-E). Longer PTA and lower GCS were both significantly correlated with worse (i) global outcomes: presence of disability on the KOSCHI and lower score on the ODS-E and (ii) select specific outcomes on the ODS-E: mobility, mood and cognition. PTA duration predicted cognitive outcome on the ODS-E independently, beyond GCS. Together, PTA duration and GCS, predicted the global KOSCHI outcome, as well as the ODS-E mobility and mood outcomes. Neither GCS nor PTA duration correlated with the ODS-E communication, impulsivity/disinhibition, headache, fatigue, sensory impairments or somatic complaints outcomes. PTA duration measured by the WPTAS is a significant unique predictor of functional cognitive outcomes in children who sustained moderate-to-severe TBI, and in combination with the GCS, a significant predictor of global, and several specific functional outcomes.

Predictive model for early functional outcomes following acute care after traumatic brain injuries: A machine learning-based development and validation study

INTRODUCTION

Few studies on early functional outcomes following acute care after traumatic brain injury (TBI) are available. The aim of this study was to develop and validate a predictive model for functional outcomes at discharge for TBI patients using machine learning methods.

PATIENTS AND METHODS

In this retrospective study, data from 5281 TBI patients admitted for acute care who were identified in the Beijing hospital discharge abstract database were analysed. Data from 4181 patients in 52 tertiary hospitals were used for model derivation and internal validation. Data from 1100 patients in 21 secondary hospitals were used for external validation. A poor outcome was defined as a Barthel Index (BI) score ≤ 60 at discharge. Logistic regression, XGBoost, random forest, decision tree, and back propagation neural network models were used to fit classification models. Performance was evaluated by the area under the receiver operating characteristic curve (AUC), the area under the precision-recall curve (AP), calibration plots, sensitivity/recall, specificity, positive predictive value (PPV)/precision, negative predictive value (NPV) and F1-score.

RESULTS

Compared to the other models, the random forest model demonstrated superior performance in internal validation (AUC of 0.856, AP of 0.786, and F1-score of 0.724) and external validation (AUC of 0.779, AP of 0.630, and F1-score of 0.604). The sensitivity/recall, specificity, PPV/precision, and NPV of the model were 71.8%, 69.2%, 52.2%, and 84.0%, respectively, in external validation. The BI score at admission, age, use of nonsurgical treatment, neurosurgery status, and modified Charlson Comorbidity Index were identified as the top 5 predictors for functional outcome at discharge.

CONCLUSIONS

We established a random forest model that performed well in predicting early functional outcomes following acute care after TBI. The model has utility for informing decision-making regarding patient management and discharge planning and for facilitating health care quality assessment and resource allocation for TBI treatment.

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).

The effect of second-generation antidepressant treatment on the attention and mental processing speed of patients with major depressive disorder: A meta-analysis study with structural equation models

Major depressive disorder (MDD) has been linked to attention and mental processing speed deficits that can be improved after pharmacological treatment. However, it is unclear whether a class of antidepressants is more effective than others to ameliorate these deficits in MDD. Additionally, the possible effects of clinical and demographic variables on improving MDD attention and processing speed deficits after antidepressant treatment are unknown. We aimed to study the possible neuropsychological effects of second-generation antidepressant classes on the attention and processing speed of MDD patients and the potential influences of clinical and demographic variables as moderators of these effects using a meta-analytic approach. Twenty-five papers were included in our study. A structural equation model meta-analysis was performed. The improvement of attention and processing speed after pharmacological treatment is clinically relevant but incomplete. Selective serotonin reuptake inhibitors (SSRIs) and dual inhibitors are the drugs causing the greatest improvement in the processing speed of MDD patients. Antidepressant class is an important variable linked to processing speed improvement after MDD treatment. However, the degree of improvement in both cognitive functions is strongly influenced by some clinical and demographic variables of depressed patients, such are age and education of the MDD patients, the duration of the antidepressant treatment, and the depression status of the patients.

Neuropsychological and behavioral disorders, functional outcomes and quality of life in traumatic brain injury victims

INTRODUCTION

the assessment of neuropsychological and behavioral disorders outcomes, functional outcomes and quality of life in traumatic brain injury victims. It was also to evaluate initial means of care provided to these patients. Finally, to study correlations between neuropsychological and behavioral disorders with demographic characteristics, injury severity, functional status and quality of life.

METHODS

it was a cross-sectional study including 50 patients with traumatic brain injury conducted in the physical medicine and rehabilitation department of Sfax. Memory disorders were tested by the mini mental state and the Glaveston orientation and amnesia tests. Executive functions were evaluated by the dysexecutive function scale. The psychological profile was evaluated using the hospital anxiety and depression scale and behavioral disorders were tested by the agitated behavior scale. Glasgow outcome scale has allowed the assessment of traumatic brain injury severity in terms of disability. Otherwise, functional capacity was measured by functional independence measure scale. Finally, health-related quality of life was measured using a generic measure (short-form-36) and the QOLIBRI scales.

RESULTS

abnormal executive functions were noted in 41 patients (82%) with a dysexcutive function average score of 33.20 ± 22.74. About psychological profile, depressive symptoms were found in 32 patients (64%). Moreover anxiety was noted in 20 patients (40%). Behavioral disorders such as aggressiveness and agitation were noted respectively in 32 (64%) and 8 patients (16%). The global social functional evolution was considered as unfavorable in 42% of the patients and favorable in 58%. Regarding to functional independence measure scale, 92% of the victims showed impairment. Memory impairment and abnormal executive functions were statistically correlated with traumatic brain injury severity. Elementary brain injury lesions shown on computed tomography were correlated with memory disorders especially for temporal, cortical brain contusion and diffuse axonal injury. Our study showed that patients with severe memory impairment, abnormal executive functions and depressive mood had significant functional.

CONCLUSION

the executive function disorders, depressed mood and the memory disorders seemed to be the most frequent among neuropsychological disorders in traumatic brain injury. We noted that it is so important to evaluate neuropsychological disorders in traumatic brain injury because they were underestimated. We have already started this experience despite the lack of means in our department. The evaluation of the executive function in addition to the classic neuropsychological assessment is essential to propose efficient means of rehabilitation.

THE EFFECT OF SECOND-GENERATION ANTIDEPRESSANT TREATMENT ON THE EXECUTIVE FUNCTIONS OF PATIENTS WITH MAJOR DEPRESSIVE DISORDER: A META-ANALYSIS STUDY WITH STRUCTURAL EQUATION MODELS

Major depressive disorder (MDD) has been linked to executive functions (EF) deficits that can be improved after pharmacological treatment, but it is unclear whether there is a class of antidepressants that is more effective than others to ameliorate these deficits in MDD. Additionally, the possible effects of clinical and demographic variables on the improvement of MDD EF deficits after pharmacological treatment are currently unknown. Our aim was to study the possible neuropsychological effects of second-generation antidepressant classes on the EF of MDD patients and the potential influence of clinical and demographic variables as moderators of these effects through a meta-analytic approach. Twenty-one papers were included in our study. A structural equation model meta-analysis was performed. The improvement of EF after pharmacological treatment is clinically relevant, but it is incomplete. This effect is influenced by age and years of education of the patients. Selective serotonin reuptake inhibitors (SSRIs) and dual inhibitors are the drugs causing the greatest improvement in EF of MDD patients. Antidepressant class is an important variable linked to EF improvement after MDD treatment, but the degree of improvement in these cognitive functions is strongly influenced by some clinical and demographic variables of patients with depression.

Early cognitive impairment is common after intracranial hemorrhage with mild traumatic brain injury

BACKDROP

The incidence of early cognitive impairment (ECI) after traumatic brain injury (TBI) is unknown. We hypothesized ECI is common and can be predicted based on Glasgow Coma Scale (GCS) and Brain Injury Guideline (BIG) category.

METHODS

A single-center, retrospective review of adult trauma patients (2014-2016) with intracranial hemorrhage (ICH) and mild TBI (GCS score, 13-15) was performed. The primary outcome was ECI, defined as a Rancho Los Amigos score less than 8. Routine cognitive evaluation is performed on all ICH patients at our institution. Comparisons between ECI and no-ECI groups regarding demographic, cognitive, and clinical outcomes were evaluated using bivariate statistics. The odds of ECI were evaluated using a multivariable logistic regression.

RESULTS

There were 465 patients with mild TBI, 70.3% were male, and the average age was 53 ± 23 years. The most common mechanism of injury was fall (41.1%) followed by motor vehicle collision (15.9%). The incidence of ECI was 51.4% (n = 239). The incidence in patients with a GCS score of 15 was 42.9%, and BIG 1 category was 42.7%. There were no differences in demographics (age, sex, comorbidities), mechanism of injury, or imaging when comparing ECI patients with no-ECI patients. The GCS score was lower in the ECI group (14.4 vs. 14.7, p < 0.001). Patients with ECI were also less likely to be discharged home (58.2% vs. 78.3%, p < 0.001). Lower GCS-verbal, BIG category 3, and presence of pelvic/extremity fractures were strong risk factors for ECI in a logistic regression model adjusted for age, loss of consciousness, anticoagulants, narcotic administration, and Rotterdam score.

CONCLUSION

Half of all patients with ICH and mild TBI had ECI. Both lower initial GCS score and BIG category 3 were associated with increased likelihood of ECI. Therefore, we recommend all patients with ICH and mild TBI undergo cognitive evaluation.

LEVEL OF EVIDENCE

Prognostic Study, Level III.

Comparing the Westmead Posttraumatic Amnesia Scale, Galveston Orientation and Amnesia Test, and Confusion Assessment Protocol as Measures of Acute Recovery Following Traumatic Brain Injury

BACKGROUND

The duration of the acute period of recovery following traumatic brain injury (TBI) remains a widely used criterion for injury severity and clinical management. Consensus regarding its most appropriate definition and assessment method has yet to be established.

OBJECTIVE

The present study compared the trajectory of recovery using 3 measures: the Westmead Post-Traumatic Amnesia Scale (WPTAS), the Galveston Orientation and Amnesia Test (GOAT), and the Confusion Assessment Protocol (CAP). Patterns of symptom recovery using the CAP were explored.

PARTICIPANTS

Eighty-two participants with moderate to severe TBI in posttraumatic amnesia (PTA) on admission to an inpatient rehabilitation hospital.

DESIGN

Prospective longitudinal study.

OUTCOME MEASURES

Length of PTA (days), agreement between measures (%, κ coefficient), and pattern of symptom recovery.

RESULTS

Participants emerged from PTA earliest on the CAP followed the GOAT, and last on the WPTAS. There was good agreement between the CAP and the GOAT as to PTA status, but both tests had poor agreement with the WPTAS. Of patients considered out of PTA on the CAP, the majority exhibited signs of amnesia on the WPTAS and one-third had clinical levels of agitation.

CONCLUSION

The WPTAS identifies a later stage of PTA recovery that requires specialized management due to ongoing amnesia and agitation. The CAP and the GOAT are less sensitive to this extended period of PTA.

The Effect of Second-Generation Antidepressant Treatment on the Memory of Patients With Major Depressive Disorder: A Meta-analysis Study With Structural Equation Models

BACKGROUND

Major depressive disorder (MDD) has been linked to episodic memory deficits that may be improved after pharmacological treatment, but it is unclear whether there is a class of antidepressants that is more effective than others to ameliorate these deficits in MDD. In addition, the possible effects of clinical and sociodemographic variables on the improvement of MDD memory deficits after pharmacological treatment are currently unknown. Our aims are to study the possible neuropsychological effects of second-generation antidepressant classes on the episodic memory of MDD patients and to study the potential effects of clinical and demographic variables as moderators of the effects of antidepressants on the memory of depressed patients through a meta-analysis approach.

PROCEDURES

Nine articles were included in our study. A structural equation model meta-analysis was performed.

RESULTS

Our results suggest that selective serotonin reuptake inhibitors and serotonine-noradrenaline reuptake inhibitors would bring about a substantial improvement in the memory of depressed patients, whereas other antidepressant classes would cause rather modest effects. Our results also suggest that clinical and demographic variables play a very important role as mediators of memory improvement after MDD treatment. Thus, a relatively low level of symptom severity, a high degree of clinical improvement, a younger age, and more years of education were positively related to memory improvement after MDD treatment.

CONCLUSIONS

Although antidepressant class is an important variable linked to memory improvement in MDD, overall, the degree of memory amelioration in depression is very closely related to clinical and demographic variables of patients with depression.

Functional Outcomes in Moderate-to-Severe Traumatic Brain Injury Survivors

Introduction:

We aimed to analyze the functional outcomes based on the admission characteristics in individuals with moderate-to-severe traumatic brain injury (TBI) over a 5-year period.

Methods:

A retrospective cohort study was conducted to assess the cognitive, physical, and functional outcomes based on traditional and novel metrics used in potential outcome prediction.

Results:

A total of 201 participants were enrolled with a mean age of 31.9 ± 11.9 years. Glasgow Coma Score (GCS) at emergency department did not correlate with the functional independence measure (FIM) score or Ranchos Los Amigos (RLA) scores at discharge. The absolute functional gain was significantly higher in individuals who sustained TBI with RLA 4–5 (34.7 ± 18.8 vs. 26.5 ± 15.9, P = 0.006). Participants with RLA 4–5 on admission to rehabilitation showed good correlation with the absolute FIM gain. On multivariate regression analysis, only age (odds ratio 0.96; 95% confidence interval: 0.93–0.98; P = 0.005) was found to be the independent predictor of good functional outcome.

Conclusions:

Initial GCS is not a predictor of functional outcome in individuals who sustained TBI. Consideration of age and development of novel functional measures might be promising to predict the outcomes in individuals with moderate-to-severe TBI.

Olfactory Training in Post-Traumatic Smell Impairment: Mild Improvement in Threshold Performances: Results from a Randomized Controlled Trial

Traumatic Brain Injury (TBI) can be associated with partial or total smell loss. Recent studies have suggested that olfactory outcome can be positively modulated after olfactory training (OT). This study's aim was to investigate OT's potential role in smell recovery after TBI-induced olfactory loss. A prospective, randomized, and controlled study was developed. Patients with TBI-induced olfactory dysfunction (n = 42) were randomized into an experimental group with OT and a control group without (nOT). OT was performed twice daily with a six odor training set during 12 weeks. Olfactory loss was assessed using subjective olfactometry (Barcelona Smell Test [BAST] 24), a visual analogue scale (VAS), and n-butanol threshold (n-BTt) at baseline at 4, 12, and 24 weeks. Additionally, patients underwent MRI of the olfactory brain and olfactory bulbs (OB). Based on the MRI results, an overall score (0-16) was developed to associate the structural neurological damage with olfactory outcomes. The primary outcome was the change in olfactory measurements (VAS and BAST-24) between baseline and 12 weeks. The secondary outcome was the association of the MRI score with olfactory outcomes at baseline, and the impact on quality of life (QoL). After 12 weeks of training, OT patients showed a significant improvement in n-BTt (0.6 ± 1.7 OT vs. -0.6 ± 1.8 nOT, p < 0.05), but not in the smell VAS and BAST-24 scores. Olfactory outcomes (VAS, BAST-24, and n-BTt) were significantly associated with MRI structural findings (p < 0.001), but not with the OB volume or olfactory sulcus length. The present study suggests that 12 weeks of OT mildly improves the olfactory threshold in TBI, whereas the overall MRI score may be used as an imaging marker of olfactory dysfunction and disease severity in TBI patients.

Acute prediction of outcome and cognitive-communication impairments following traumatic brain injury: The influence of age, education and site of lesion

BACKGROUND

Communication impairment following a traumatic brain injury (TBI) has been well documented, yet information regarding communication skills in the acute period following the injury is limited in the literature. Also, little is known about the influence of TBI severity (mild, moderate or severe) on cognitive-communication impairments and how these impairments are related to short-term functional outcome. The goal of this study was to assess the performance of adults with mild, moderate and severe TBI on different language tests and to determine how this performance is related to functional capacity. We also aimed to explore which variables among age, sex, education, TBI severity and site of cerebral damage would predict initial language impairments.

METHODS

Several language tests were administered to a sample of 145 adult patients with TBI of a range of severities admitted to an acute care service and to 113 healthy participants from the community.

RESULTS

TBI patients of a range of severities performed poorly on all language tests in comparison to the healthy controls. In addition, patients with mild TBI performed better than the moderate and severe groups, except on the reading test and on the semantic naming test. In addition, their performance on verbal fluency, conversational discourse and procedural discourse tasks predicted acute functional outcome. Finally, age, education and TBI severity and site of lesion predicted some language performance. A left temporal lesion was associated with poorer performance in conversational discourse and auditory comprehension tasks, a left frontal lesion with a decrease in the verbal fluency results and a right parietal lesion with decreased auditory comprehension and reasoning skills.

CONCLUSION

Health care professionals working in the acute care setting should be aware of the possible presence of cognitive-communication impairments in patients with TBI, even for those with mild TBI. These deficits can lead to functional communication problems and assistance may be required for tasks frequently encountered in acute care requiring intact comprehension and expression.

Preliminary validation study of the Sydney Post-Traumatic Amnesia Scale (SYPTAS) in children with traumatic brain injury aged 4 to 7 years

The aim of this study was to assess the validity (developmental, concurrent, and predictive) of the Sydney Post-Traumatic Amnesia Scale (SYPTAS) for assessment of post-traumatic amnesia (PTA) in 4 to 7 year old children with traumatic brain injury (TBI). The design of this study is a retrospective cohort study. The SYPTAS was administered to 35 children (26 boys) aged 4.0 to 7.8 years who were consecutively admitted to a children's hospital with mild (n = 26), moderate (n = 3), or severe (n = 7) TBI. Concurrent validity of the SYPTAS was assessed against the Glasgow Coma Scale Scores (GCS). Predictive validity of the SYPTAS for functional outcomes was evaluated against the King's Outcome Scale for Childhood Head Injury (KOSCHI) at discharge and outpatient follow-ups. The length of PTA, measured by the SYPTAS, was invariant of children's chronological age, confirming the scale's developmental validity. Longer PTA was associated with lower GCS, endorsing concurrent validity of PTA duration measured by the SYPTAS, as a clinical indicator of TBI severity. PTA duration measured by the SYPTAS was a significant predictor of functional outcomes on the KOSCHI at discharge and follow-ups. This study provides evidence that the SYPTAS has good developmental, concurrent and predictive validity for assessment of PTA in children aged 4 to 7 years. PTA duration assessed by the SYPTAS is a clinical indicator of TBI severity and can aid rehabilitation planning post TBI.

Prediction of behavioural and cognitive deficits in patients with traumatic brain injury at an acute rehabilitation setting

OBJECTIVE

The goal of this study was to identify factors that would predict short-term neuropsychological outcome in patients with traumatic brain injury (TBI) hospitalized in an acute rehabilitation setting.

METHODS

Data was collected in the context of an acute early rehabilitation setting of a trauma centre. A brief neuropsychological assessment was carried out for 348 patients within a month following their trauma.

RESULTS

Length of post-traumatic amnesia (PTA) was the best predictor of behavioural, memory and executive function variables within a month post TBI. The odds of being agitated, labile, irritable and disinhibited at one month post trauma were almost six times higher for those with PTA that lasted more than 7 days compared to those with a PTA of less than 24 hours. Also, the odds of having a higher mental manipulation score (less significant executive function impairment) were almost two times lower for those with frontal lesions, and three to six times lower for those with PTA of more than 24 hours. In addition, TBI severity, education and age were considered good predictors of some aspects of neuropsychological outcome.

CONCLUSION

This model may help clinicians and administrators recognize the probable post-traumatic deficits as quickly as possible and to plan interventions as well as post-acute discharge orientation accordingly and early on.

The Serum Phosphorylated Neurofilament Heavy Subunit as a Predictive Marker for Outcome in Adult Patients after Traumatic Brain Injury

The serum phosphorylated neurofilament heavy subunit (pNF-H) is a nervous system-specific protein that is released from damaged neural tissue after traumatic brain injury (TBI). The aim of this study was to elucidate the usefulness of serum pNF-H as a predictive marker for the outcome of patients after TBI. Patients with TBI (Glasgow Coma Scale score of 13 or less on admission) were included. Patients who were younger than age 18, dependent on others for daily activities before injury, pregnant, or who were not likely to survive for more than 24 h after injury were excluded. The outcome was assessed using the Glasgow Outcome Scale at 6 months after injury. Blood was collected from subjects (n = 32), and the serum pNF-H value was assessed at 24 and 72 h after TBI. The optimal cutoff value and usefulness of the serum pNF-H value for predicting the long-term outcome were investigated. We found that the serum pNF-H value at 24 h after injury was a good predictive marker of death at 6 months (p < 0.001) after injury. The optimal cutoff value was 240 pg/mL, and the area under the curve in the receiver operating characteristic analysis was 0.930. The serum pNF-H value at 72 h after injury was correlated with an unfavorable outcome (vegetative state or death) at 6 months (p < 0.01) with a cutoff value of 80 pg/mL. Collectively, the results of this study indicate that the serum pNF-H value is a useful predictive marker for patient outcome after TBI.

Global Outcome and Late Seizures After Penetrating Versus Closed Traumatic Brain Injury: A NIDRR TBI Model Systems Study

BACKGROUND

If and how much dural penetration influences long-term outcome after traumatic brain injury (TBI) is understudied, especially within the civilian population.

OBJECTIVES

Using the large TBI Model Systems cohort, this study assessed and compared penetrating TBI (PTBI) and closed TBI with respect to global outcome and late seizures 2 years after injury.

METHODS

After performing unadjusted PTBI versus closed TBI comparisons, multivariate regression models were built and analyzed for both outcomes by including the following additional predictors: length of unconsciousness, posttraumatic amnesia duration, hospital length of stay, age, gender, race, marital status, education level, problem substance abuse, and preinjury employment status.

RESULTS

The collapsed Glasgow Outcome Scale model (n = 6111) showed significant secondary effects of PTBI with employment status. When employed before injury, individuals with PTBI were 2.62 times more likely (95% confidence interval, 1.92-3.57) to have a lower Glasgow Outcome Scale category. The final model for late seizures (n = 6737) showed a significant main effect for PTBI. Adjusting for other predictors, individuals with PTBI were 2.78 times more likely (95% confidence interval, 1.93-3.99) than those with closed TBI to be rehospitalized for a seizure.

CONCLUSION

This study empirically demonstrates that penetrating injury mechanism has important prognostic implications.

Neuropsychological functioning in a national cohort of severe traumatic brain injury: demographic and acute injury-related predictors

OBJECTIVES

To determine the rates of cognitive impairment 1 year after severe traumatic brain injury (TBI) and to examine the influence of demographic, injury severity, rehabilitation, and subacute functional outcomes on cognitive outcomes 1 year after severe TBI.

SETTING

National multicenter cohort study over 2 years.

PARTICIPANTS

Patients (N = 105), aged 16 years or older, with Glasgow Coma Scale score of 3 to 8 and Galveston Orientation and Amnesia Test score of more than 75.

MAIN MEASURES

Neuropsychological tests representing cognitive domains of Executive Functions, Processing Speed, and Memory. Injury severity included Rotterdam computed tomography score, Glasgow Coma Scale score, and posttraumatic amnesia (PTA) duration, together with length of rehabilitation and Glasgow Outcome Scale-Extended score.

RESULTS

In total, 67% of patients with severe TBI had cognitive impairment. Executive Functions, Processing Speed, and Memory were impaired in 41%, 58%, and 57% of patients, respectively. Using multiple regression analysis, Processing Speed was significantly related to PTA duration, Glasgow Outcome Scale-Extended score, and length of inpatient rehabilitation (R = 0.30); Memory was significantly related to Glasgow Outcome Scale-Extended score (R = 0.15); and Executive Functions to PTA duration (R = 0.10). Rotterdam computed tomography and Glasgow Coma Scale scores were not associated with cognitive functioning at 1 year postinjury.

CONCLUSION

Findings highlight cognitive consequences of severe TBI, with nearly two-thirds of patients showing cognitive impairments in at least 1 of 3 cognitive domains. Regarding injury severity predictors, only PTA duration was related to cognitive functioning.

Duration of post-traumatic amnesia as a predictor of functional outcome in school-age children: a systematic review

AIM

In adults, duration of post-traumatic amnesia (PTA) is a powerful early predictor of functional outcomes in traumatic brain injury. The aim of this work was to assess the predictive validity of PTA duration for outcomes in children (6-18y).

METHOD

PsycINFO, MEDLINE, Web of Science, and Embase were searched for papers published to January 2014. Ten studies met inclusion criteria: they used standardized instruments to assess PTA and functional outcomes, and examined relationships between the two. Outcomes were classified according to (1) the International Classification of Functioning, Disability and Health (ICF) core sets for neurological conditions for post-acute care and (2) global functioning and quality of life. Methodological quality was rated for each study.

RESULTS

The search identified 10 studies of moderate mean quality (M=11.8 out of 18). Longer PTA duration related to worse functional outcomes: global functioning and in the two ICF categories ('body function', 'activities and participation'). Relationships between PTA duration and quality of life and the ICF category of 'body structure' were not examined. PTA duration was, in 46 out of 60 (76.67%) instances, a stronger predictor of outcomes than other indices of injury severity.

CONCLUSION

Longer PTA duration is a valid predictor of worse outcomes in school-age children. Thus, PTA should be routinely assessed in children after traumatic brain injury.

Outcome in Women with Traumatic Brain Injury Admitted to a Level 1 Trauma Center

Background. The aim of this study was to compare acute outcome between men and women after sustaining a traumatic brain injury (TBI). Methods. A total of 5,642 patients admitted to the Traumatic Brain Injury Program of the McGill University Health Centre-Montreal General Hospital between 2000 and 2011 and diagnosed with a TBI were included in the study. The overall percentage of women with TBI was 30.6% (n = 1728). Outcome measures included the length of stay (LOS), the Extended Glasgow Outcome Scale (GOSE), the functional independence measure instrument (FIM), discharge destination, and mortality rate. Results. LOS, GOSE, the FIM ratings, and discharge destination did not show significant differences between genders once controlling for several confounding variables and running the appropriate diagnostic tests (P < 0.05). However, women had less chance of dying during their acute care hospitalization than men of the same age, with the same TBI severity and following the same mechanism of injury. Although gender was a statistically significant predictor, its contribution in explaining variation in mortality was small. Conclusion. More research is needed to better understand gender differences in mortality; as to date, the research findings remain inconclusive.

Predictors of memory and processing speed dysfunctions after traumatic brain injury

Background. The aims of this study were to evaluate the predictive value of admission Glasgow Coma Scale (GCS) scores, duration of unconsciousness, neurosurgical intervention, and countercoup lesion on the impairment of memory and processing speed functions six months after a traumatic brain injury (TBI) based on a structural equation modeling. Methods. Thirty TBI patients recruited from Neurosurgical Department at the Kaohsiung Medical University Hospital were administered the Wechsler Memory Scale-III (WMS-III) and the Wechsler Adult Intelligence Scale-III processing speed index to evaluate the memory and processing speed functions. Results. The study showed that GCS scores accounted for 40% of the variance in memory/processing speed. No significant predictive effects were found for the other three variables. GCS classification at the time of TBI seems to correspond moderately to the severity of memory/processing speed dysfunctions. Conclusions. The present study demonstrated that admission GCS score is a robust predictor of memory/processing speed dysfunctions after TBI. The results should be replicated with a large sample of patients with TBI, or be extended by examining other potential clinical predictors.

Head injury and loss of consciousness raise the likelihood of developing and maintaining PTSD symptoms

Mild traumatic brain injury has been associated with higher prevalence of posttraumatic stress disorder (PTSD). The extent to which head injury or loss of consciousness predicts PTSD is unknown. To evaluate the contribution of head injury and loss of consciousness to the occurrence of PTSD, we made a longitudinal evaluation of 1,260 road accident survivors admitted to the emergency department with head injury (n = 287), head injury and loss of consciousness (n = 115), or neither (n = 858). A telephone-administered posttraumatic symptoms scale inferred PTSD and quantified PTSD symptoms at 10 days and 8 months after admission. The study groups had similar heart rate, blood pressure, and pain levels in the emergency department. Survivors with loss of consciousness and head injury had higher prevalence of PTSD and higher levels of PTSD symptoms, suggesting that patients with head injury and loss of consciousness reported in the emergency department are at higher risk for PTSD.

Development and external validation of a new PTA assessment scale

Background

Post-traumatic amnesia (PTA) is a key symptom of traumatic brain injury (TBI). Accurate assessment of PTA is imperative in guiding clinical decision making. Our aim was to develop and externally validate a short, examiner independent and practical PTA scale, by selecting the most discriminative items from existing scales and using a three-word memory test.

Methods

Mild, moderate and severe TBI patients and control subjects were assessed in two separate cohorts, one for derivation and one for validation, using a questionnaire comprised of items from existing PTA scales. We tested which individual items best discriminated between TBI patients and controls, represented by sensitivity and specificity. We then created our PTA scale based on these results. This new scale was externally evaluated for its discriminative value using Receiver Operating Characteristic (ROC) analysis and compared to existing PTA scales.

Results

The derivation cohort included 126 TBI patients and 31 control subjects; the validation cohort consisted of 132 patients and 30 controls. A set of seven items was eventually selected to comprise the new PTA scale: age, name of hospital, time, day of week, month, mode of transport and recall of three words. This scale demonstrated adequate discriminative values compared to existing PTA scales on three consecutive administrations in the validation cohort.

Conclusion

We introduce a valid, practical and examiner independent PTA scale, which is suitable for mild TBI patients at the emergency department and yet still valuable for the follow-up of more severely injured TBI patients.

Predicting Outcome after Traumatic Brain Injury

The purpose of this review is to look at the most recent work carried out on predicting outcome after traumatic brain injury (TBI). TBI is a leading cause of death and disability but prediction of long-term outcome for individual patients is difficult. In particular, predicting outcome in the first few hours or days after injury is limited by the paucity of scoring systems or clinical models available. Many clinical variables have been studied to determine if they may play a role in outcome prediction, including age, admission Glasgow Coma Score and pupillary reactivity. Newer variables being studied include serum biomarkers, abnormalities seen on magnetic resonance imaging and data obtained from evoked potentials and electroencephalography studies. There are many factors that impact on outcome and a perfect model is yet to be developed. Models must take into account the economic status of the country in which the trauma occurs. It is important that less affluent nations are not left behind in the search for accurate prognostic modelling.

Fatores associados à amnésia pós-traumática de longa duração

OBJETIVO: Identificar fatores relacionados à amnésia pós-traumática de longa duração. MÉTODO: Estudo prospectivo, longitudinal, com 187 vítimas de trauma cranioencefálico contuso, idade >14 anos, atendidos em hospital de referência para trauma. As variáveis independentes foram: idade, sexo, gravidade do trauma cranioencefálico, local e tipo de lesão, número de lesões encefálicas e uso de medicação com atividade em sistema nervoso central ou corticoides. RESULTADO: O modelo de regressão logística múltipla ajustado pela variável área de lesão (intra/extra axial) evidenciou: Escala de Coma de Glasgow inicial <12 (OR=20,17); Maximum Abbreviated Injury Scale/cabeça >3 (OR=2,80) e uso de Fenitoína (OR=2,60), Midazolan (OR=2,83) ou ambas as drogas (OR=3,83). CONCLUSÃO: O uso do Midazolan e da Fenitoína, além da gravidade do trauma cranioencefálico, destacaram-se como fatores relacionados à amnésia de longa duração.

Functional level during sub-acute rehabilitation after traumatic brain injury: course and predictors of outcome

OBJECTIVES

To describe the functional level during sub-acute rehabilitation after moderate and severe traumatic brain injury (TBI) and to evaluate the impact of pre-injury and injury-related factors as predictors of early recovery.

MATERIAL AND METHODS

A prospective study of 55 patients with moderate (n = 21) and severe (n = 34) TBI who received specialized, inpatient rehabilitation. Functional level was assessed by the FIM. Possible predictors were analysed in a regression model using FIM total score at discharge as outcome.

RESULTS

At discharge from sub-acute rehabilitation, on average 53 (+/-24) days post-injury, 57% of moderate TBI patients and 91% of severe TBI patients were still disabled with a FIM score < 126. The disability was mild (FIM 109-126) in 95% with moderate TBI and in 62% with severe TBI. The disability was severe (FIM < 72) in 24% with severe TBI. Only one patient did not improve. Predictors of functional level at discharge from rehabilitation were Glasgow Coma Scale (GCS) score at rehabilitation admission (B = 5.991), FIM total score at rehabilitation admission (B = 0.393), length of stay (LOS) in the rehabilitation unit (B = 0.264) and length of Post-Traumatic Amnesia (PTA) (B = -0.120). Together, these predictors explained 86% of variance of FIM total scores at discharge.

CONCLUSION

Less than half of moderate TBI patients reached a normal functional level at discharge from sub-acute rehabilitation. A short PTA period, a high GCS score and FIM score at admission to rehabilitation and a longer stay in the rehabilitation unit were positive predictors of functional level at discharge.

Post-traumatic amnesia predicts long-term cerebral atrophy in traumatic brain injury

PRIMARY OBJECTIVE

To examine post-traumatic amnesia (PTA) and its relation to long-term cerebral atrophy in persons with traumatic brain injury (TBI) using objective indicators of PTA duration and Quantitative Magnetic Resonance Imaging (QMRI). It was hypothesized that longer PTA would predict later generalized atrophy (increased ventricle-to-brain ratio (VBR)). As a guide in assessing patients with TBI, this study determined the probability of developing chronic cerebral atrophy based on PTA duration.

RESEARCH DESIGN

Probability model using 60 adult patients with mild-to-severe TBI.

MAIN OUTCOMES AND RESULTS

A logistic regression model with a cut-off determined by normative QMRI data confirmed that longer PTA duration predicts increased VBR. A probability model demonstrated a 6% increase in the odds of developing later atrophy on neuroimaging with each additional day of PTA.

CONCLUSIONS

PTA has previously proven to be a good indicator of later cognitive recovery and functional outcome and also predicts long-term parenchymal change.

Early prediction of language impairment following traumatic brain injury

PRIMARY OBJECTIVE

This study investigated which factors collected early in the acute care setting (age, education, cerebral imaging, Glasgow Coma Scale score) would predict initial impairments of language comprehension and expression in patients with traumatic brain injury (TBI) of all severity.

METHODS AND PROCEDURES

Results of language tests carried out during the patients' stay in an acute tertiary trauma centre were obtained. These tests measured performance in the areas of confrontation naming, auditory comprehension, semantic and letter category naming and comprehension of verbal absurdities. Data for the predictive variables were gathered by retrospective chart review. Stepwise multiple linear regressions were carried out on the predictive variables.

MAIN OUTCOMES AND RESULTS

Education and TBI severity as measured with the GCS score were the most significant factors predicting language deficits in the acute care setting.

CONCLUSIONS

These findings will serve to guide health care professionals in predicting prognosis for cognitive-communication deficits post-TBI and in planning for appropriate resources in speech-language pathology to meet these patients' needs.

Cognitive and functional outcomes of terror victims who suffered from traumatic brain injury

PRIMARY OBJECTIVE

To describe the outcomes of terror victims suffered from traumatic brain injury (TBI).

RESEARCH DESIGN

Retrospective chart review of 17 terror and 39 non-terror TBI patients treated in a rehabilitation department during the same period.

METHODS AND PROCEDURE

Variables include demographic data, Injury Severity Scale (ISS), length of stay (LOS) and imaging results. ADL was measured using the Functional Independence Measurement (FIM), cognitive and memory functions were measured using the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) battery and the Rivermead Battery Memory Test (RBMT), respectively.

MAIN OUTCOME AND RESULTS

Terror TBI patients were significantly younger, had higher ISS score and higher rates of intracerebral haemorrhage (ICH), brain surgery and penetrating brain injuries than the non-terror TBI group. There was no difference in mean LOS, mean FIM values, mean FIM gain and mean cognitive and memory improvement between groups. Terror victims suffered from a higher percentage of post-traumatic epilepsy (35% vs. 10%, p=0.05), whereas the rate of PTSD and the rate of return to previous occupation were similar between groups.

CONCLUSIONS

Although TBI terror victims had more severe injury, they gained most of ADL functions and their rehabilitation outcomes were similar to non-terror TBI patients. These favourable results were achieved due to a comprehensive interdisciplinary approach to terror victims and also by national support which allowed an adequate period of treatment and sufficient resources as needed.

[The effect of age on executive functioning after acquired brain injury in adults]

INTRODUCTION

Executive functioning deficits have often been described in normal aging. They are also known to be a frequent sequel of traumatic brain injury, where patients may exhibit severe long-standing impairments in instrumental activities of daily living. One could therefore expect that cerebral lesions affecting executive functioning would result in more severe impairments in older patients. We previously developed an ecological assessment of executive functions, consisting of a cooking task, requiring multitasking abilities and known to be sensitive to a dysexecutive syndrome [Cortex 36 (2000) 649-669]. The aim of this study was to analyze the effect of age on the cognitive and ecological assessments of executive functions in a group of patients with acquired brain injury (ABI) resulting in a dysexecutive syndrome. Studies in this area usually focus on patients older than 60 or 65, but we chose to analyze the effect of age in a younger population. We hypothesized that older patients would have poorer performances on the cognitive and ecological tests of executive functioning, when compared to younger patients.

METHODS

Forty-five patients with ABI resulting in frontal lesions and a dysexecutive syndrome participated in this study. Patients underwent a comprehensive battery of cognitive tests assessing executive functioning, as well as the cooking task. We also studied a group of 12 control subjects who performed the cooking task.

RESULTS

No effect of age was found on performance in the cooking task in the control group. Age was not related to demographic parameters or injury severity in the ABI group. Although the ABI group was relatively young (mean age: 40.3 years (S.D.=12.5), ranging from 17 to 63), results indicated a significant deleterious effect of age on the cognitive tests of executive functioning in the ABI group. We also highlighted a significant worsening of patients' performance in the cooking task with age, and this effect was found on several variables of task analysis: the number of errors and occurrence of dangerous behaviors.

CONCLUSION

Our study demonstrates the deleterious effect of aging on cognitive and ecological assessment of executive functioning after ABI. The strength of this study is that it deviated from the traditional age considered in studies of elderly populations and focused on younger patients. It is therefore important to consider the implication that this may have on a patient's rehabilitation program and postinjury discharge.

Measuring recovery in new learning and memory following traumatic brain injury: A mixed-effects modeling approach

Patterns of recovery from traumatic brain injury (TBI) vary greatly across individuals. Using archival data from the Traumatic Brain Injury Model Systems, recovery of memory following TBI as measured by scores on the Rey Auditory Verbal Learning Test (RAVLT) through 5 years postinjury was examined via mixed-effects modeling. Individual-level variables of age and posttraumatic amnesia duration were significant predictors of 1-year RAVLT total score. None of the variables examined predicted the trajectory of memory recovery after 1 year. Mixed-effects analyses can be helpful in determining the effect of intervention while allowing for missing data across time points.