Chronic immunosuppression across 12 months and high ability of acute and subacute CNS-injury biomarker concentrations to identify individuals with complicated mTBI on acute CT and MRI.

BACKGROUND: Identifying individuals with intracranial injuries following mild traumatic brain injury (mTBI), i.e. complicated mTBI cases, is important for follow-up and prognostication. The main aims of our study were (1) to assess the temporal evolution of blood biomarkers of CNS injury and inflammation in individuals with complicated mTBI determined on computer tomography (CT) and magnetic resonance imaging (MRI); (2) to assess the corresponding discriminability of both single- and multi-biomarker panels, from acute to chronic phases after injury. METHODS: Patients with mTBI (n = 207), defined as Glasgow Coma Scale score between 13 and 15, loss of consciousness < 30 min and post-traumatic amnesia < 24 h, were included. Complicated mTBI - i.e., presence of any traumatic intracranial injury on neuroimaging - was present in 8% (n = 16) on CT (CT+) and 12% (n = 25) on MRI (MRI+). Blood biomarkers were sampled at four timepoints following injury: admission (within 72 h), 2 weeks (± 3 days), 3 months (± 2 weeks) and 12 months (± 1 month). CNS biomarkers included were glial fibrillary acidic protein (GFAP), neurofilament light (NFL) and tau, along with 12 inflammation markers. RESULTS: The most discriminative single biomarkers of traumatic intracranial injury were GFAP at admission (CT+: AUC = 0.78; MRI+: AUC = 0.82), and NFL at 2 weeks (CT+: AUC = 0.81; MRI+: AUC = 0.89) and 3 months (MRI+: AUC = 0.86). MIP-1ß and IP-10 concentrations were significantly lower across follow-up period in individuals who were CT+ and MRI+. Eotaxin and IL-9 were significantly lower in individuals who were MRI+ only. FGF-basic concentrations increased over time in MRI- individuals and were significantly higher than MRI+ individuals at 3 and 12 months. Multi-biomarker panels improved discriminability over single biomarkers at all timepoints (AUCs > 0.85 for admission and 2-week models classifying CT+ and AUC ≈ 0.90 for admission, 2-week and 3-month models classifying MRI+). CONCLUSIONS: The CNS biomarkers GFAP and NFL were useful single diagnostic biomarkers of complicated mTBI, especially in acute and subacute phases after mTBI. Several inflammation markers were suppressed in patients with complicated versus uncomplicated mTBI and remained so even after 12 months. Multi-biomarker panels improved diagnostic accuracy at all timepoints, though at acute and 2-week timepoints, the single biomarkers GFAP and NFL, respectively, displayed similar accuracy compared to multi-biomarker panels.

The prognostic importance of traumatic axonal injury on early MRI: the Trondheim TAI-MRI grading and quantitative models.

OBJECTIVES: We analysed magnetic resonance imaging (MRI) findings after traumatic brain injury (TBI) aiming to improve the grading of traumatic axonal injury (TAI) to better reflect the outcome. METHODS: Four-hundred sixty-three patients (8-70 years) with mild (n = 158), moderate (n = 129), or severe (n = 176) TBI and early MRI were prospectively included. TAI presence, numbers, and volumes at predefined locations were registered on fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging, and presence and numbers on T2*GRE/SWI. Presence and volumes of contusions were registered on FLAIR. We assessed the outcome with the Glasgow Outcome Scale Extended. Multivariable logistic and elastic-net regression analyses were performed. RESULTS: The presence of TAI differed between mild (6%), moderate (70%), and severe TBI (95%). In severe TBI, bilateral TAI in mesencephalon or thalami and bilateral TAI in pons predicted worse outcomes and were defined as the worst grades (4 and 5, respectively) in the Trondheim TAI-MRI grading. The Trondheim TAI-MRI grading performed better than the standard TAI grading in severe TBI (pseudo-R2 0.19 vs. 0.16). In moderate-severe TBI, quantitative models including both FLAIR volume of TAI and contusions performed best (pseudo-R2 0.19-0.21). In patients with mild TBI or Glasgow Coma Scale (GCS) score 13, models with the volume of contusions performed best (pseudo-R2 0.25-0.26). CONCLUSIONS: We propose the Trondheim TAI-MRI grading (grades 1-5) with bilateral TAI in mesencephalon or thalami, and bilateral TAI in pons as the worst grades. The predictive value was highest for the quantitative models including FLAIR volume of TAI and contusions (GCS score <13) or FLAIR volume of contusions (GCS score ≥ 13), which emphasise artificial intelligence as a potentially important future tool. CLINICAL RELEVANCE STATEMENT: The Trondheim TAI-MRI grading reflects patient outcomes better in severe TBI than today's standard TAI grading and can be implemented after external validation. The prognostic importance of volumetric models is promising for future use of artificial intelligence technologies. KEY POINTS: Traumatic axonal injury (TAI) is an important injury type in all TBI severities. Studies demonstrating which MRI findings that can serve as future biomarkers are highly warranted. This study proposes the most optimal MRI models for predicting patient outcome at 6 months after TBI; one updated pragmatic model and a volumetric model. The Trondheim TAI-MRI grading, in severe TBI, reflects patient outcome better than today's standard grading of TAI and the prognostic importance of volumetric models in all severities of TBI is promising for future use of AI.

Frequency and predictors of headache in the first 12 months after traumatic brain injury: results from CENTER-TBI.

BACKGROUND: Headache is a prevalent and debilitating symptom following traumatic brain injury (TBI). Large-scale, prospective cohort studies are needed to establish long-term headache prevalence and associated factors after TBI. This study aimed to assess the frequency and severity of headache after TBI and determine whether sociodemographic factors, injury severity characteristics, and pre- and post-injury comorbidities predicted changes in headache frequency and severity during the first 12 months after injury. METHODS: A large patient sample from the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) prospective observational cohort study was used. Patients were stratified based on their clinical care pathway: admitted to an emergency room (ER), a ward (ADM) or an intensive care unit (ICU) in the acute phase. Headache was assessed using a single item from the Rivermead Post-Concussion Symptoms Questionnaire measured at baseline, 3, 6 and 12 months after injury. Mixed-effect logistic regression analyses were applied to investigate changes in headache frequency and associated predictors. RESULTS: A total of 2,291 patients responded to the headache item at baseline. At study enrolment, 59.3% of patients reported acute headache, with similar frequencies across all strata. Female patients and those aged up to 40 years reported a higher frequency of headache at baseline compared to males and older adults. The frequency of severe headache was highest in patients admitted to the ICU. The frequency of headache in the ER stratum decreased substantially from baseline to 3 months and remained from 3 to 6 months. Similar trajectory trends were observed in the ICU and ADM strata across 12 months. Younger age, more severe TBI, fatigue, neck pain and vision problems were among the predictors of more severe headache over time. More than 25% of patients experienced headache at 12 months after injury. CONCLUSIONS: Headache is a common symptom after TBI, especially in female and younger patients. It typically decreases in the first 3 months before stabilising. However, more than a quarter of patients still experienced headache at 12 months after injury. Translational research is needed to advance the clinical decision-making process and improve targeted medical treatment for headache. TRIAL REGISTRATION: ClinicalTrials.gov NCT02210221.

The Epidemiology of Moderate and Severe Traumatic Brain Injury in Central Norway.

INTRODUCTION: Few studies account for prehospital deaths when estimating incidence and mortality rates of moderate and severe traumatic brain injury (msTBI). In a population-based study, covering both urban and rural areas, including also prehospital deaths, the aim was to estimate incidence and mortality rates of msTBI. Further, we studied the 30-day and 6-month case-fatality proportion of severe TBI in relation to age. METHODS: All patients aged ≥17 years who sustained an msTBI in Central Norway were identified by three sources: (1) the regional trauma center, (2) the general hospitals, and (3) the Norwegian Cause of Death Registry. Incidence and mortality rates were standardized according to the World Health Organization's world standard population. Case-fatality proportions were calculated by the number of deaths from severe TBI at 30 days and 6 months, divided by all patients with severe TBI. RESULTS: The overall incidence rates of moderate and severe TBI were 4.9 and 6.7 per 100,000 person-years, respectively, increasing from age 70 years. The overall mortality rate was 3.4 per 100,000 person-years, also increasing from age 70 years. Incidence and mortality rates were highest in men. The case-fatality proportion in people with severe TBI was 49% in people aged 60-69 years and 81% in people aged 70-79 years. CONCLUSION: The overall incidence and mortality rates for msTBI in Central Norway were low but increased from age 70 years, and among those ≥80 years of age with severe TBI, nearly all died. Overall estimates are strongly influenced by high incidence and mortality rates in the elderly, and studies should therefore report age-specific estimates, for better comparison of incidence and mortality rates.

Trajectories of Persistent Postconcussion Symptoms and Factors Associated With Symptom Reporting After Mild Traumatic Brain Injury.

OBJECTIVE: To examine the trajectories of persistent postconcussion symptoms (PPCS) after mild traumatic brain injury (MTBI) and to investigate which injury-related and personal factors are associated with symptom reporting. DESIGN: Prospective longitudinal cohort study. Follow-up at 3 and 12 months postinjury. SETTING: A level 1 trauma center and an emergency outpatient clinic. PARTICIPANTS: Patients with MTBI (n=358), trauma controls (n=75), and community controls (n=78). MAIN OUTCOME MEASURES: Symptoms were assessed with the British Columbia Postconcussion Symptom Inventory (BC-PSI). Participants were categorized as having moderate to severe PPCS (msPPCS) when reporting ≥3 moderate/severe symptoms or a BC-PSI total score of ≥13. BC-PSI total scores were compared between the groups and were further used to create cutoffs for reliable change by identifying uncommon and very uncommon change in symptoms in the community control group. Associations between symptom reporting and 25 injury-related and personal factors were examined. RESULTS: The MTBI group had a similar prevalence of msPPCS at 3 and 12 months (21%) and reported more symptoms than the control groups. Analyses of individual trajectories, however, revealed considerable change in both msPPCS and BC-PSI total scores in the MTBI group, where both worsening and improvement was common. Intracranial lesions on computed tomography were associated with a greater likelihood of improving from 3 to 12 months. Those with msPPCS at both assessments were more likely to be women and to have these personal preinjury factors: reduced employment, pain, poor sleep, low resilience, high neuroticism and pessimism, and a psychiatric history. CONCLUSIONS: Group analyses suggest a stable prevalence of msPPCS the first year postinjury. However, there was considerable intraindividual change. Several personal factors were associated with maintaining symptoms throughout the first year.

Long-term post-concussion symptoms. / Langvarige plager etter hjernerystelse.

Concussion is common and usually resolves without complications. However, persistent symptoms occur in 10-15 % of patients. These post-concussion symptoms are predominantly somatic, cognitive and emotional. The condition is most common in those with previous somatic and mental health issues. The causes underlying long-term post-concussion symptoms are unclear, but a biopsychosocial explanatory model is currently regarded as the most appropriate basis for diagnosis and treatment. This clinical review article is based on key literature and our own clinical experiences with patients who have these long-term post-concussion symptoms.

Personal Factors Associated With Postconcussion Symptoms 3 Months After Mild Traumatic Brain Injury.

OBJECTIVE: To describe personal factors in patients with mild traumatic brain injury (MTBI) and 2 control groups and to explore how such factors were associated with postconcussion symptoms (PCSs). DESIGN: Prospective cohort study. SETTING: Level 1 trauma center and outpatient clinic. PARTICIPANTS: Participants (N=541) included patients with MTBI (n=378), trauma controls (n=82), and community controls (n=81). MAIN OUTCOME MEASURES: Data on preinjury health and work status, personality, resilience, attention deficit/hyperactivity, and substance use. Computed tomography (CT) findings and posttraumatic amnesia were recorded. Symptoms were assessed at 3 months with the British Columbia Postconcussion Symptom Inventory and labeled as PCS+ if ≥3 symptoms were reported or the total score was ≥13. Predictive models were fitted with penalized logistic regression using the least absolute shrinkage and selection operator (lasso) in the MTBI group, and model fit was assessed with optimism-corrected area under the curve (AUC) of the receiver operating characteristic curve. RESULTS: There were few differences in personal factors between the MTBI group and the 2 control groups without MTBI. Rates of PCS+ were 20.8% for the MTBI group, 8.0% for trauma controls, and 1.3% for community controls. In the MTBI group, there were differences between the PCS+ and PCS- group on most personal factors and injury-related variables in univariable comparisons. In the lasso models, the optimism-corrected AUC for the full model was 0.79, 0.73 for the model only including personal factors, and 0.63 for the model only including injury variables. Working less than full time before injury, having preinjury pain and poor sleep quality, and being female were among the selected predictors, but also resilience and some personality traits contributed in the model. Intracranial abnormalities on CT were also a risk factor for PCS. CONCLUSIONS: Personal factors convey important prognostic information in patients with MTBI. A vulnerable work status and preinjury health problems might indicate a need for follow-up and targeted interventions.

Cognitive Reserve Moderates Cognitive Outcome After Mild Traumatic Brain Injury.

OBJECTIVE: To investigate whether cognitive reserve moderates differences in cognitive functioning between patients with mild traumatic brain injury (MTBI) and controls without MTBI and to examine whether patients with postconcussion syndrome have lower cognitive functioning than patients without postconcussion syndrome at 2 weeks and 3 months after injury. DESIGN: Trondheim MTBI follow-up study is a longitudinal controlled cohort study with cognitive assessments 2 weeks and 3 months after injury. SETTING: Recruitment at a level 1 trauma center and at a general practitioner-run, outpatient clinic. PARTICIPANTS: Patients with MTBI (n=160) according to the World Health Organization criteria, trauma controls (n=71), and community controls (n=79) (N=310). MAIN OUTCOME MEASURES: A cognitive composite score was used as outcome measure. The Vocabulary subtest was used as a proxy of cognitive reserve. Postconcussion syndrome diagnosis was assessed at 3 months with the British Columbia Postconcussion Symptom Inventory. RESULTS: Linear mixed models demonstrated that the effect of vocabulary scores on the cognitive composite scores was larger in patients with MTBI than in community controls at 2 weeks and at 3 months after injury (P=.001). Thus, group differences in the cognitive composite score varied as a function of vocabulary scores, with the biggest differences seen among participants with lower vocabulary scores. There were no significant differences in the cognitive composite score between patients with (n=29) and without (n=131) postconcussion syndrome at 2 weeks or 3 months after injury. CONCLUSION: Cognitive reserve, but not postconcussion syndrome, was associated with cognitive outcome after MTBI. This supports the cognitive reserve hypothesis in the MTBI context and suggests that persons with low cognitive reserve are more vulnerable to reduced cognitive functioning if they sustain an MTBI.

Return to work after severe traumatic brain injury: a national study with a one-year follow-up of neurocognitive and behavioural outcomes.

The objectives were to investigate the frequency of return-to-work (RTW) one year after severe traumatic brain injury (sTBI: Glasgow Coma Scale, GCS 3-8) and to identify which demographic and injury-related characteristics and neurocognitive factors are associated with RTW. This study is part of a prospective national study on sTBI conducted in all four Norwegian Trauma Referral Centres, including patients aged >15 years over a period of three years (n = 378). For the purpose of this study, only pre-employed individuals of working age (16 to 67 years) were investigated for RTW (n = 143), and of these, 104 participants underwent neuropsychological testing. Measures of acute injury severity, neuropsychological composite scores (Memory, Processing Speed, Executive Functions) at the one-year follow-up, and the Behaviour Rating Inventory of Executive Functions (patient- and relative reports) were explored as predictors of RTW. The frequency of RTW was 54.5%. Multivariate logistic regression analyses identified younger age, shorter length of stay in intensive care, better Processing Speed scores, and lower levels of metacognitive difficulties as rated by relatives as significant predictors of RTW. Findings support the importance of neuropsychological measures in predicting long-term RTW and highlight the need to address neurocognitive and behavioural difficulties to improve RTW after sTBI.

Diffusion kurtosis imaging in mild traumatic brain injury and postconcussional syndrome.

Aims of this study were to investigate white matter (WM) and thalamus microstructure 72 hr and 3 months after mild traumatic brain injury (TBI) with diffusion kurtosis imaging (DKI) and diffusion tensor imaging (DTI), and to relate DKI and DTI findings to postconcussional syndrome (PCS). Twenty-five patients (72 hr = 24; 3 months = 23) and 22 healthy controls were recruited, and DKI and DTI data were analyzed with Tract-Based Spatial Statistics (TBSS) and a region-of-interest (ROI) approach. Patients were categorized into PCS or non-PCS 3 months after injury according to the ICD-10 research criteria for PCS. In TBSS analysis, significant differences between patients and controls were seen in WM, both in the acute stage and 3 months after injury. Fractional anisotropy (FA) reductions were more widespread than kurtosis fractional anisotropy (KFA) reductions in the acute stage, while KFA reductions were more widespread than the FA reductions at 3 months, indicating the complementary roles of DKI and DTI. When comparing patients with PCS (n = 9), without PCS (n = 16), and healthy controls, in the ROI analyses, no differences were found in the acute DKI and DTI metrics. However, near-significant differences were observed for several DKI metrics obtained in WM and thalamus concurrently with symptom assessment (3 months after injury). Our findings indicate a combined utility of DKI and DTI in detecting WM microstructural alterations after mild TBI. Moreover, PCS may be associated with evolving alterations in brain microstructure, and DKI may be a promising tool to detect such changes.

Frequency and prognostic factors of olfactory dysfunction after traumatic brain injury.

OBJECTIVE: To assess the frequency and factors associated with posttraumatic olfactory dysfunction, including anosmia, in a follow-up of patients with moderate and severe traumatic brain injury (TBI). METHODS: The setting was a cross-sectional study of patients that were consecutively included in the Trondheim TBI database, comprising injury-related variables. Eligible participants 18-65 years were contacted 9-104 months post trauma and asked olfactory-related questions. Those reporting possible posttraumatic change of olfaction were invited to further examination using the Sniffin' Sticks panel. RESULTS: Of 211 eligible participants, 182 (86.3%) took part in telephone interviews and 25(13.7%) were diagnosed with olfactory dysfunction. 60% of these, or 8.2% of all participants, had anosmia. In age-adjusted logistic regression analyses, fall (OR 2.5, 95% CI 1.0-6.2), skull base fracture (OR 2.9, 95% CI 1.2-7.1) and cortical contusion(s) (OR 6.0, 95% CI 2.1-17.3) were associated with olfactory dysfunction. In an analysis of anosmia, fall (OR 3.4, 95% CI 1.1-10.6) and cortical contusion(s) (OR 19.7, 95% CI 2.5-156.0) were associated with the outcome. CONCLUSION: Of the study participants 13.7% had olfactory dysfunction and 8.2% had anosmia. Higher age, trauma caused by fall and CT displaying skull base fracture and cortical contusion(s) were related to olfactory dysfunction.

Traumatic axonal injury: Relationships between lesions in the early phase and diffusion tensor imaging parameters in the chronic phase of traumatic brain injury.

This prospective study of traumatic brain injury (TBI) patients investigates fractional anisotropy (FA) from chronic diffusion tensor imaging (DTI) in areas corresponding to persistent and transient traumatic axonal injury (TAI) lesions detected in clinical MRI from the early phase. Thirty-eight patients (mean 24.7 [range 13-63] years of age) with moderate-to-severe TBI and 42 age- and sex-matched healthy controls were included. Patients underwent 1.5-T clinical MRI in the early phase (median 7 days), including fluid-attenuated inversion recovery (FLAIR) and T2* gradient echo (T2*GRE) sequences. TAI lesions from the early phase were characterized as nonhemorrhagic or microhemorrhagic. In the chronic phase (median 3 years), patients and controls were imaged at 3 T with FLAIR, T2*GRE, T1, and DTI sequences. TAI lesions were classified as transient or persistent. The FLAIR/T2*GRE images from the early phase were linearly registered to the FA images from the chronic phase and lesions manually segmented on the FA-registered FLAIR/T2*GRE images. For regions of interest (ROIs) from both nonhemorrhagic and microhemorrhagic lesion, we found a significant linear trend of lower mean FA from ROIs in healthy controls to ROIs in patients without either nonhemorrhagic or microhemorrhagic lesions and further to transient and finally persistent lesion ROIs (P < 0.001). Histogram analyses showed lower FA in persistent compared with transient nonhemorrhagic lesion ROIs (P < 0.001), but this was not found in microhemorrhagic lesion ROIs (P = 0.08-0.55). The demonstrated linear trend of lower FA values from healthy controls to persistent lesion ROIs was found in both nonhemorrhagic and microhemorrhagic lesions and indicates a gradual increasing disruption of the microstructure. Lower FA values in persistent compared with transient lesions were found only in nonhemorrhagic lesions. Thus, clinical MRI techniques are able to depict important aspects of white matter pathology across the stages of TBI. © 2016 Wiley Periodicals, Inc.

Altered Cognitive Control Activations after Moderate-to-Severe Traumatic Brain Injury and Their Relationship to Injury Severity and Everyday-Life Function.

This study investigated how the neuronal underpinnings of both adaptive and stable cognitive control processes are affected by traumatic brain injury (TBI). Functional magnetic resonance imaging (fMRI) was undertaken in 62 survivors of moderate-to-severe TBI (>1 year after injury) and 68 healthy controls during performance of a continuous performance test adapted for use in a mixed block- and event-related design. Survivors of TBI demonstrated increased reliance on adaptive task control processes within an a priori core region for cognitive control in the medial frontal cortex. TBI survivors also had increased activations related to time-on-task effects during stable task-set maintenance in right inferior parietal and prefrontal cortices. Increased brain activations in TBI survivors had a dose-dependent linear positive relationship to injury severity and were negatively correlated with self-reported cognitive control problems in everyday-life situations. Results were adjusted for age, education, and fMRI task performance. In conclusion, evidence was provided that the neural underpinnings of adaptive and stable control processes are differently affected by TBI. Moreover, it was demonstrated that increased brain activations typically observed in survivors of TBI might represent injury-specific compensatory adaptations also utilized in everyday-life situations.

Factors Affecting Caregiver Burden 1 Year After Severe Traumatic Brain Injury: A Prospective Nationwide Multicenter Study.

OBJECTIVES: To assess burden in the caregivers of patients with severe traumatic brain injury (TBI) 1 year postinjury, related to caregiver's demographic data and social network, patient's demographic data, injury severity, and functional status. DESIGN: Prospective national multicenter study. Self-report from caregivers, patient data collected from the national cohort on patients with severe TBI. PARTICIPANTS: 92 caregivers. MAIN OUTCOME MEASURE: The Caregiver Burden Scale (CBS). RESULTS: Total caregiver burden was reported high in 16% of caregivers and moderate in 34%. The mean total burden index was 2.12, indicating a moderate burden. Caregivers reported highest scores on the General strain index, followed by the Disappointment index. Poor social network, feeling loneliness, and caring for patients with severe disability were significant predictors of higher burden in univariate analyses (P < .01). Multiple linear regression analyses showed that experiencing loneliness and caring for a patient with more severe disability were independent predictors for higher caregiver burden for all CBS indices. Marital status (married) and low frequency of meeting friends were significant results in some indices. CONCLUSIONS: Lack of a social network, feeling loneliness, and patient's functional status are predictors of caregiver burden. General strain, disappointment, and isolation were identified as areas in which caregiver burden is high.

Functional Recovery and Life Satisfaction in the First Year After Severe Traumatic Brain Injury: A Prospective Multicenter Study of a Norwegian National Cohort.

OBJECTIVES: (1) To examine the impact of demographic and acute injury-related variables on functional recovery and life satisfaction after severe traumatic brain injury (sTBI) and (2) to test whether postinjury functioning, postconcussive symptoms, emotional state, and functional improvement are related to life satisfaction. DESIGN: Prospective national multicenter study. SETTING: Level 1 trauma centers in Norway. PARTICIPANTS: 163 adults with sTBI. MAIN MEASURES: Functional recovery between 3 and 12 months postinjury measured with Glasgow Outcome Scale Extended, Rivermead Postconcussion Symptoms Questionnaire, Hospital Anxiety and Depression Scale, and satisfaction with life situation. RESULTS: 60% of cases experienced functional improvement from 3 to 12 months postinjury. Multivariate logistic regression analysis revealed that discharge to a rehabilitation department from acute care (odds ratio [OR] = 2.14; P < .05) and fewer days with artificial ventilation (OR = 1.04; P < .05) were significantly related to improvement. At 12 months postinjury, 85% were independent in daily activities. Most participants (63%) were satisfied with their life situation. Regression analysis revealed that older age (>65 years), low education, better functional outcome, and the absence of depressive and postconcussion symptoms were significant (P < .05) predictors of life satisfaction. Functional improvement was significantly associated with emotional state but not to life satisfaction. CONCLUSION: Following sTBI, approximately two-thirds of survivors improve between 3 and 12 months postinjury and are satisfied with their life. Direct discharge from acute care to specialized rehabilitation appears to increase functional recovery.

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.

High-level mobility in chronic traumatic brain injury and its relationship with clinical variables and magnetic resonance imaging findings in the acute phase.

OBJECTIVES: To compare high-level mobility in individuals with chronic moderate-to-severe traumatic brain injury (TBI) with matched healthy controls, and to investigate whether clinical variables and magnetic resonance imaging (MRI) findings in the acute phase can predict high-level motor performance in the chronic phase. DESIGN: A longitudinal follow-up study. SETTING: A level 1 trauma center. PARTICIPANTS: Individuals (N=136) with chronic TBI (n=65) and healthy matched peers (n=71). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: High-Level Mobility Assessment Tool (HiMAT) and the revised version of the HiMAT performed at a mean of 2.8 years (range, 1.5-5.4y) after injury. RESULTS: Participants with chronic TBI had a mean HiMAT score of 42.7 (95% confidence interval [CI], 40.2-45.2) compared with 47.7 (95% CI, 46.1-49.2) in the control group (P<.01). Group differences were also evident using the revised HiMAT (P<.01). Acute-phase clinical variables and MRI findings explained 58.8% of the variance in the HiMAT score (P<.001) and 59.9% in the revised HiMAT score (P<.001). Lower HiMAT scores were associated with female sex (P=.031), higher age at injury (P<.001), motor vehicle collisions (P=.030), and posttraumatic amnesia >7 days (P=.048). There was a tendency toward an association between lower scores and diffuse axonal injury in the brainstem (P=.075). CONCLUSIONS: High-level mobility was reduced in participants with chronic, either moderate or severe TBI compared with matched peers. Clinical variables in the acute phase were significantly associated with high-level mobility performance in participants with TBI, but the role of early MRI findings needs to be further investigated. The findings of this study suggest that the clinical variables in the acute phase may be useful in predicting high-level mobility outcome in the chronic phase.

Rate of disorders of consciousness in a prospective population-based study of adults with traumatic brain injury.

OBJECTIVE: Establish rate of disorders of consciousness (DOC) and course of recovery in adults who have sustained severe traumatic brain injury (sTBI). SETTING: Four Norwegian neurosurgical departments. PARTICIPANTS: Vegetative or minimally conscious patients. DESIGN: Prospective, longitudinal population-based study of adults with sTBI with follow-ups at 3, 12, and 24-36 months postinjury. MAIN MEASURES: Coma Recovery Scale-Revised, Glasgow Coma Scale, Extended Glasgow Outcome Scale, and Disability Rating Scale. RESULTS: Three months postinjury, 2% of the sTBI population remained in a vegetative or minimally conscious state, reduced by the half after 1 year, corresponding to average annual age-adjusted incidence rates of DOC of 0.09 per 100 000 3 months post-sTBI. At 3 and 12 months, the incidence was 0.06 and 0.01 per 100 000 for the vegetative state and 0.03 and 0.04 per 100 000 for the minimally conscious state. Diagnostic categorization was stable between 12 and 24-36 months, although clinically relevant improvements were observed in minimally conscious patients. CONCLUSION: The data suggest that prolonged DOC is rare following sTBI in Norway, contrary to the commonly held belief that improvements in intensive care treatment have resulted in an increased incidence of DOC. Prolonged DOC was associated with severity of injury, subcortical lesions, and diffuse axonal injury.

Improvement in Functional Outcome from 6 to 12 Months After Moderate and Severe Traumatic Brain Injury Is Frequent, But May Not Be Detected With the Glasgow Outcome Scale Extended.

The aims of this study were (1) to report outcome and change in outcome in patients with moderate and severe traumatic brain injury (mo/sTBI) between 6 and 12 months post-injury as measured by the Glasgow Outcome Scale Extended (GOSE), (2) to explore if demographic/injury-related variables can predict improvement in GOSE score, and (3) to investigate rate of improvement in Disability Rating Scale (DRS) score, in patients with a stable GOSE. All surviving patients ≥16 years of age who were admitted with mo/sTBI (Glasgow Coma Scale [GCS] score ≤13) to the regional trauma center in Central Norway between 2004 and 2019 were prospectively included (n = 439 out of 503 eligible). GOSE and DRS were used to assess outcome. Twelve-months post-injury, 13% with moTBI had severe disability (GOSE 2-4) versus 27% in sTBI, 26% had moderate disability (GOSE 5-6) versus 41% in sTBI and 62% had good recovery (GOSE 7-8) versus 31% in sTBI. From 6 to 12 months post-injury, 27% with moTBI and 32% with sTBI had an improvement, whereas 6% with moTBI and 6% with sTBI had a deterioration in GOSE score. Younger age and higher GCS score were associated with improved GOSE score. Improvement was least frequent for patients with a GOSE score of 3 at 6 months. In patients with a stable GOSE score of 3, an improvement in DRS score was observed in 22 (46%) patients. In conclusion, two thirds and one third of patients with mo/sTBI, respectively, had a good recovery. Importantly, change, mostly improvement, in GOSE score between 6 and 12 months was frequent and argues against the use of 6 months outcome as a time end-point in research. The GOSE does, however, not seem to be sensitive to actual change in function in the lower categories and a combination of outcome measures may be needed to describe the consequences after TBI.