Neuropsychological Outcomes in Patients with Complicated Versus Uncomplicated Mild Traumatic Brain Injury: 6-Month Follow-Up

Cognitive Outcome After Complicated Mild Traumatic Brain Injury: A Literature Review and Meta-Analysis

Cognitive outcome for mild traumatic brain injury (mTBI) with positive brain imaging (complicated mTBI) was compared with that for mTBI with normal imaging (uncomplicated mTBI) and with moderate to severe TBI, using meta-analysis. Twenty-three studies utilizing objective neurocognitive tests were included in the analysis. At less than 3 months post-injury, complicated mTBI was associated with poorer cognitive outcomes than uncomplicated mTBI, but deficits were not comparable to those with moderate-severe TBI. After 3 months post-injury, a similar pattern was detected. Beyond 3 months, deficits in complicated mTBI relative to those with uncomplicated mTBI were present in processing speed, memory, executive function, and language, although the latter may be the result of reduced semantic fluency. The effect size of deficits in these domains was more marked in moderate-severe TBI. The available data support the use of complicated mTBI as a distinct classification in the prediction of cognitive outcome. The extent of cognitive deficit in complicated mTBI was small and unlikely to cause significant disability. However, patients with complicated mTBI constitute a broad category encompassing individuals who may differ markedly in the nature and extent of intracranial imaging abnormality, and further studies are warranted. Limitations of the available studies include small, selected samples; variations in TBI severity classification; absence of validity ("effort") testing; differing imaging methodology; and lack of long-term follow-up.

Brain dynamics in triple-network interactions and its relation to multiple cognitive impairments in mild traumatic brain injury

Traumatic brain injury (TBI) disrupt the coordinated activity of triple-network and produce impairments across several cognitive domains. The triple-network model posits a key role of the salience network (SN) that regulates interactions with the central executive network (CEN) and default mode network (DMN). However, the aberrant dynamic interactions among triple-network and associations with neurobehavioral symptoms in mild TBI was still unclear. In present study, we used brain network interaction index (NII) and dynamic functional connectivity to examine the time-varying cross-network interactions among the triple-network in 109 acute patients, 41 chronic patients, and 65 healthy controls. Dynamic cross-network interactions were significantly increased and more variable in mild TBI compared to controls. Crucially, mild TBI exhibited an increased NII as enhanced integrations between the SN and CEN while reduced coupling of the SN with DMN. The increased NII also implied much severer and multiple domains of cognitive impairments at both acute and chronic mild TBI. Abnormities in time-varying engagement of triple-network is a clinically relevant neurobiological signature of psychopathology in mild TBI. The findings provided align with and advance an emerging perspective on the importance of aberrant brain dynamics associated with highly disparate cognitive and behavioral outcomes in trauma.

Validation of the Neuropsychological Assessment Battery Screening Module (NAB-SM) in patients with traumatic brain injury

This study cross-validates the screening module of the Neuropsychological Assessment Battery (NAB-SM) with a battery of well validated neuropsychological tests (Convergent Validity Test Battery: CVTB) in a Traumatic Brain Injury (TBI) population. Forty-four participants with "mild-complicated" to "severe" TBI were recruited from a cohort of patients attending an outpatient clinic at a UK major trauma center. The NAB-SM Total Index score and an abbreviated short-form, from which a TBI Index was derived, both showed good classification accuracy in predicting impairment as measured by the CVTB mean score. These indices also accurately identified impairment as defined by the base rate of low scores across individual CVTB indices measuring mental processing speed, working memory, memory and executive functioning. The NAB-SM and its derived TBI index therefore have significant utility as a cognitive screening tool for use in either inpatient (acute) or outpatient TBI populations.

Complicated versus uncomplicated mild traumatic brain injuries: A comparison of psychological, cognitive, and post-concussion symptom outcomes

INTRODUCTION

A complicated mild traumatic brain injury (MTBI) is defined as mild by all clinical severity indicators but is complicated due to a traumatic intracranial abnormality visible on neuroimaging. Researchers have reported mixed findings regarding whether neuropsychological and functional outcomes following complicated MTBI are worse than, or similar to, outcomes following uncomplicated MTBI. This study examined patients referred from a Taiwanese emergency department to a neurosurgical outpatient clinic. Participants with complicated MTBI, uncomplicated MTBI, and those who did not undergo head computed tomography (CT) were compared on psychological, neuropsychological, and post-concussion symptom outcomes within 21 days of injury.

METHOD

Participants with complicated MTBI (n = 42), uncomplicated MTBI (n = 77), and no head CT (n = 172) completed the Paced Auditory Serial Attention Test, Taiwanese Word Sequence Learning Test, a semantic Verbal Fluency Test, the Checklist of Post-Concussion Symptoms, and the Beck Depression and Anxiety Inventories.

RESULTS

No significant differences were observed between groups on any measure. For individual post-concussion symptoms, dizziness, anxiety, and attention difficulty were endorsed more often after uncomplicated MTBIs, but these group differences were not significant after controlling for multiple comparisons.

CONCLUSIONS

Participants with complicated MTBIs did not have worse acute or subacute outcomes than participants with uncomplicated MTBIs or no head CT. These results are consistent with many studies finding comparable outcomes between those with complicated and uncomplicated MTBIs. This study is limited by small sample size and minimal information on intracranial abnormalities, broadly categorizing groups based on positive or negative neuroimaging as opposed to specific lesion types and locations.

Subjective Cognitive Decline and Related Cognitive Deficits

Since late stage dementia, including Alzheimer's disease (AD), cannot be reversed by any available drugs, there is increasing research interest in the preclinical stage of AD, i.e., subjective cognitive decline (SCD). SCD is characterized by self-perceptive cognitive decline but is difficult to detect using objective tests. At SCD stage, the cognitive deficits can be more easily reversed compared to that of mild cognitive impairment (MCI) and AD only if accurate diagnosis of SCD and early intervention can be developed. In this paper, we review the recent progress of SCD research including current assessment tools, biomarkers, neuroimaging, intervention and expected prognosis, and the potential relevance to traumatic brain injury (TBI)-induced cognitive deficits.

Outcomes after Complicated and Uncomplicated Mild Traumatic Brain Injury at Three-and Six-Months Post-Injury: Results from the CENTER-TBI Study

The objective of this study was to provide a comprehensive examination of the relation of complicated and uncomplicated mild traumatic brain injury (mTBI) with multidimensional outcomes at three- and six-months after TBI. We analyzed data from the Collaborative European NeuroTrauma Effectiveness Research (CENTER-TBI) research project. Patients after mTBI (Glasgow Coma scale (GCS) score of 13-15) enrolled in the study were differentiated into two groups based on computed tomography (CT) findings: complicated mTBI (presence of any traumatic intracranial injury on first CT) and uncomplicated mTBI (absence of any traumatic intracranial injury on first CT). Multidimensional outcomes were assessed using seven instruments measuring generic and disease-specific health-related quality of life (HRQoL) (SF-36 and QOLIBRI), functional outcome (GOSE), and psycho-social domains including symptoms of post-traumatic stress disorder (PTSD) (PCL-5), depression (PHQ-9), and anxiety (GAD-7). Data were analyzed using a multivariate repeated measures approach (MANOVA-RM), which inspected mTBI groups at three- and six-months post injury. Patients after complicated mTBI had significantly lower GOSE scores, reported lower physical and mental component summary scores based on the SF-36 version 2, and showed significantly lower HRQoL measured by QOLIBRI compared to those after uncomplicated mTBI. There was no difference between mTBI groups when looking at psychological outcomes, however, a slight improvement in PTSD symptoms and depression was observed for the entire sample from three to six months. Patients after complicated mTBI reported lower generic and disease specific HRQoL and worse functional outcome compared to individuals after uncomplicated mTBI at three and six months. Both groups showed a tendency to improve from three to six months after TBI. The complicated mTBI group included more patients with an impaired long-term outcome than the uncomplicated group. Nevertheless, patients, clinicians, researchers, and decisions-makers in health care should take account of the short and long-term impact on outcome for patients after both uncomplicated and complicated mTBI.

Factors Associated With Degree and Length of Recovery in Children With Mild and Complicated Mild Traumatic Brain Injury

BACKGROUND

A complicated mild traumatic brain injury (C-mTBI) is an mTBI with some form of intracranial abnormality identified radiographically. The lack of knowledge in recovery patterns and no clear guidelines on return to activity in children with C-mTBI provide unique challenges to physicians.

OBJECTIVE

To examine recovery patterns among three cohorts: mTBI, mTBI with skull fracture only (mTBI-SF), and C-mTBI via a cross-sectional survey.

METHODS

Caregivers of children with mTBI (from hospital database queries 2010-2013) were mailed a questionnaire on preinjury health, postinjury recovery, and activity patterns before and after injury. We examined degree (0-10 with 10 being complete recovery) and length (in months) of recovery in children with mTBI, and associations of potential risk factors to these variables.

RESULTS

Of the 1777 surveyed, a total of 285 complete responses were analyzed for this study. Data included 175 (61.4%) children with mTBI, 33 (11.6%) children with mTBI-SF, and 77 (27.0%) children with C-mTBI. Older age and C-mTBI (vs mTBI) were significantly associated with a lower degree and longer period of recovery (P < .05). Predicted probabilities of complete recovery for children with mTBI, those with mTBI-SF, and those with C-mTBI were 65.5%, 52.7%, and 40.0%, respectively. Predicted probabilities of not yet completely recovered after more than a year since injury for these groups were 11.3%, 24.4%, and 37.6%, respectively.

CONCLUSION

These results demonstrate significant differences in children with different forms of mTBI, and argue for further investigation of treatment plans individualized for each form of mTBI.

Improvement and Prediction of Memory and Executive Functions in Patients Admitted to a Neurosurgery Service With Complicated and Uncomplicated Mild Traumatic Brain Injury

OBJECTIVES

To compare neuropsychological performances between patients with and without intracranial abnormalities after mild traumatic brain injury (mTBI) and assess the relationship between demographics, injury severity, and self-reported symptom characteristics with improvements in memory and executive functions (8 weeks to 1 year postinjury).

SETTING

Inpatient/outpatient followed up at the Department of Physical Medicine and Rehabilitation, Oslo, Norway.

PARTICIPANTS

Patients were divided into groups of complicated (n = 73) or uncomplicated mTBIs (n = 77) based on intracranial findings on computed tomographic or magnetic resonance imaging brain scans.

DESIGN

Prospective, longitudinal cohort study.

MAIN MEASURES

Neuropsychological assessments of memory and executive functions, self-reports of postconcussion, depression, posttraumatic stress symptoms, and general functioning at 8 weeks and 1 year postinjury.

RESULTS

Longitudinal data showed that patients with complicated and uncomplicated mTBIs had similar cognitive performance and improvements. Hierarchical linear modeling revealed that individuals with early posttraumatic stress disorder and/or depressive symptoms performed worse on measures of Memory functions, and those with younger age (<40 years) and lower education (<12 years) performed worse on measures of Executive functions.

CONCLUSION

Findings are suggestive of a good cognitive outcome following complicated and uncomplicated mTBIs. Early assessments of posttraumatic stress disorder and depression seem useful in identifying those most vulnerable having poorer cognitive outcomes, providing further interventions that may affect emotional and cognitive recovery.

The course and prognostic factors of cognitive outcomes after traumatic brain injury: A systematic review and meta-analysis

Despite indications that TBI may be a precursor of cognitive decline and subsequent development of Alzheimer's disease, little is known about the time course of this relationship and the factors involved. This systematic review summarizes the evidence pertinent to this subject matter. All English language studies of longitudinal design, and works cited within them, found in six literature databases, were considered, and their quality assessed. Of 65 articles appraised, 44 studies were selected. Results were organized by timing of assessments, injury severity, and cognitive domains assessed. Differences in the course of cognitive performance were observed across injury severity groups and cognitive domains, with differential proportions of reports of improvement, decline, or no change over time. The evidence for genetic, sex-, age-, and injury-related factors as determinants of cognitive outcome was inconsistent. The non-uniform trajectory of cognitive performance post-TBI supports the notion that this construct is non-homogeneous, and that different factors influence its course. Agreement on a core set of predictors and consideration of psychometric properties of outcome measures is needed.