Torgeir Hellstrøm

Missing a follow-up after mild traumatic brain injury—Does it matter?

Abstract Objective: This study sought to identify potential differing clinical characteristics between patients with a mild traumatic brain injury (MTBI) who attended a planned follow-up session and not. This study investigated whether clinical characteristics and attendance for a planned follow-up service 2-months after injury could be related to return-to-work (RTW) 1-year later. Method: Prospective cohort study of 343 patients with MTBI admitted consecutively to the Department of Neurosurgery in 2009–2011. Demographic and clinical data were obtained from the hospital files and data about sick leave from The Norwegian Labour and Welfare Service. Patients were categorized into two groups according to their attendance. Results: One hundred and sixty-one (67%) patients attended (AG) and 80 (33%) did not (NAG) attend their follow-up appointments. The AG had significantly more frequently intracranial pathology on CT scan, had consumed less alcohol and were older. Logistic regression showed that follow-up attendance (OR = 16.89) and sick leave before injury (OR = 9.70) are unfavourably related to RTW at 12-months. Skull fracture and cause of injury had no influence of the outcome. Conclusion: Not attending the follow-up has a favourable outcome after MBTI, indicating that these patients have a reduced need for medical and rehabilitation support for their brain injury.

Predictors for Return to Work in Subjects with Mild Traumatic Brain Injury

Objective. To predict return to work (RTW) at 12 months for patients who either were sick-listed or were at risk to be sick-listed with persistent postconcussion symptoms (PCS) at six to eight weeks after injury. Method. A prospective cohort study of 151 patients with mild traumatic brain injury (MTBI) admitted consecutively to outpatient clinics at two University Hospitals in Norway. The study was conducted as part of a randomised clinical trial. Injury characteristics were obtained from the medical records. Sick leave data from one year before to one year after MTBI were obtained from the Norwegian Labour and Welfare Service. Self-report questionnaires were used to obtain demographic and symptom profiles. Results. We observed a significant negative association between RTW at 12 months and psychological distress, global functioning, and being sick-listed at two months after MTBI, as well as having been sick-listed the last year before injury. Conclusion. Psychological distress, global functioning postinjury, and the sick leave trajectory of the subjects were negative predictors for RTW. These findings should be taken into consideration when evaluating future vocational rehabilitation models.

Measurement Properties of the High-Level Mobility Assessment Tool for Mild Traumatic Brain Injury

Background The High-Level Mobility Assessment Tool (HiMAT) was developed to quantify balance and mobility problems after traumatic brain injury (TBI). Measurement properties of the HiMAT have not been tested in the mild TBI (MTBI) population. Objective The aim of this study was to examine the reliability, validity, and responsiveness of the HiMAT in a sample of the MTBI population. Design A cohort, pretest-posttest, comparison study was conducted. Methods Ninety-two patients (69% men, 31% women) with a mean age of 37.1 years (SD=13.8) and a mean Glasgow Coma Scale score of 14.7 (SD=0.7) were recruited from Oslo University Hospital. All patients were tested with the HiMAT (range of scores=0 [worst] to 54 [best]) at 3 months postinjury. Fifty-one patients were retested at 6 months. A subgroup of 25 patients was selected for the reliability testing. Balance function reported on the Rivermead Post Concussion Symptoms Questionnaire was chosen as a criterion and anchor. Criterion-related validity was studied with correlation analysis. Intraclass correlation coefficients (ICCs) were used for assessing interrater and intrarater reliability. Minimal detectable change (MDC) for the HiMAT was estimated. Responsiveness was assessed with receiver operating characteristic curve analyses. Results The mean HiMAT sum score was 46.2 (95% confidence interval=44.4 to 48.1). The HiMAT had a ceiling effect of 22.8%. The correlation between HiMAT scores and self-reported balance problems was large (r=−.63, P<.001). Interrater and intrarater reliability of the HiMAT sum score was high (interrater ICC=.99, intrarater ICC=.95). The MDC was −3 to +4 points. Responsiveness was good, and the HiMAT discriminated well between patients with self-perceived improved balance function versus unchanged balance function (area under the curve=0.86). Limitations The small sample size, a ceiling effect, and lack of a gold standard were limitations of the study. Conclusions The HiMAT demonstrated satisfactory measurement properties for patients with MTBI. The HiMAT can be used as an outcome measure of balance and mobility problems in patients with MTBI.

Multidisciplinary outpatient treatment in patients with mild traumatic brain injury: A randomised controlled intervention study

ABSTRACT Objective: To evaluate the efficacy of a multidisciplinary outpatient follow-up programme compared to follow-up by a general practitioner for patients being at-risk or sick-listed with persistent post-concussion symptoms two months after a mild traumatic brain injury. Design: Randomised controlled trial. Patients: One hundred fifty-one patients, 16–56 years. Methods: Multidisciplinary outpatient rehabilitation with individual contacts and a psycho-educational group intervention at two outpatient rehabilitation clinics compared to follow-up by a general practitioner after the multidisciplinary examination. Primary outcome was sustainable return-to-work first year post-injury. Secondary outcomes were post-concussion symptoms, disability, the patient’s impressions of change and psychological distress. Results: Days to sustainable return-to-work was 90 in the intervention and 71 in the control group (p = 0.375). The number of post-concussion symptoms were fewer in the intervention (6) compared to the control group (8) at 12 months (p = 0.041). No group differences were observed for disability (p = 0.193), patients impression of change (p = 0.285) or psychological distress (p = 0.716). Conclusion: The multidisciplinary outpatient follow-up programme focusing on better understanding and reassurance of favourable outcome for mild traumatic brain injury did not improve return-to-work, but may have reduced the development of post-concussion symptoms. Additional studies should focus on which factors exhibit a direct impact on return-to-work.

Predicting Outcome 12 Months after Mild Traumatic Brain Injury in Patients Admitted to a Neurosurgery Service

Objective Accurate outcome prediction models for patients with mild traumatic brain injury (MTBI) are key for prognostic assessment and clinical decision-making. Using multivariate machine learning, we tested the unique and added predictive value of (1) magnetic resonance imaging (MRI)-based brain morphometric and volumetric characterization at 4-week postinjury and (2) demographic, preinjury, injury-related, and postinjury variables on 12-month outcomes, including global functioning level, postconcussion symptoms, and mental health in patients with MTBI. Methods A prospective, cohort study of patients (n = 147) aged 16–65 years with a 12-month follow-up. T1-weighted 3 T MRI data were processed in FreeSurfer, yielding accurate cortical reconstructions for surface-based analyses of cortical thickness, area, and volume, and brain segmentation for subcortical and global brain volumes. The 12-month outcome was defined as a composite score using a principal component analysis including the Glasgow Outcome Scale Extended, Rivermead Postconcussion Questionnaire, and Patient Health Questionnaire-9. Using leave-one-out cross-validation and permutation testing, we tested and compared three prediction models: (1) MRI model, (2) clinical model, and (3) MRI and clinical combined. Results We found a strong correlation between observed and predicted outcomes for the clinical model (r = 0.55, p < 0.001). The MRI model performed at the chance level (r = 0.03, p = 0.80) and the combined model (r = 0.45, p < 0.002) were slightly weaker than the clinical model. Univariate correlation analyses revealed the strongest association with outcome for postinjury factors of posttraumatic stress (Posttraumatic Symptom Scale-10, r = 0.61), psychological distress (Hospital Anxiety and Depression Scale, r = 0.52), and widespread pain (r = 0.43) assessed at 8 weeks. Conclusion We found no added predictive value of MRI-based measures of brain cortical morphometry and subcortical volumes over and above demographic and clinical features.

Longitudinal changes in brain morphology from 4 weeks to 12 months after mild traumatic brain injury: Associations with cognitive functions and clinical variables

ABSTRACT Objective: To investigate longitudinal changes in cortical and subcortical volumes in patients with mild traumatic brain injury (MTBI) and to evaluate whether such changes were associated with self-reported post-concussive symptoms, global functional outcomes and neuropsychological functioning. Methods: This was a prospecitve, longitudinal cohort study of patients with complicated (i.e presence of intracranial abnormalities on the day of injury CT) and uncomplicated MTBI (i.e, absence of intracranial abnormalities). Magnetic resonance imaging (MRI) was performed at approximately 4 weeks and 12 months. We utilized a 3T MRI system, cortical reconstruction and volumetric segmentation by FreeSurfer software. We included 33 patients with uncomplicated and 29 with complicated MTBI, who were aged 16–65 years. Results: 12 months after MTBI, significant within-group volume reductions were detected in the left accumbens area and right caudate nucleus for both patients groups, but no significant differences between the groups were revealed. No associations between volumetric variables and post-concussive symptoms or global functioning were found. The left temporal thickness was significantly associated with executive functioning. Conclusion: Structural subcortical alterations occur after complicated and uncomplicated MTBIs but these findings were not associated with symptoms burden or functional outcomes. Nonetheless, worse executive functioning was found in patients with shrinkage of the left temporal lobe.

Volumetric and morphometric MRI findings in patients with mild traumatic brain injury

Abstract Objective: This study compared cortical and sub-cortical volumes between patients with complicated (i.e. presence of intracranial abnormality on the day-of-injury CT) and uncomplicated (i.e. absence of intracranial abnormality) mild traumatic brain injury (MTBI) 4 weeks post-injury. The study hypothesized regionally decreased brain volumes and reduced cortical thickness in patients with complicated MTBIs compared with uncomplicated MTBI. Methods: This study was part of a larger 2 years cohort study on MTBI. Baseline clinical and magnetic resonance imaging (MRI) data were compared for those with complicated and uncomplicated MTBI. It identified 168 patients with MTBI (90 uncomplicated and 78 complicated), aged 16–65 years. 3T MRI-system (Signa HDxt, GE Medical Systems, Milwaukee, WI) and cortical reconstruction and volumetric segmentation by FreeSurfer software have been used. Results: No significant differences between uncomplicated and complicated MTBIs were found in neuroanatomic volumes and cortical thickness after controlling for age, gender and education. The complicated MTBI group showed larger ventricles compared with the uncomplicated group, but this effect diluted when adjusting for potential confounders. Conclusion: The study findings suggest that the classification of complicated and uncomplicated MTBI may be too broad to differentiate volumetric and morphometric effects of injury in the early post-injury phase.

Disability and quality of life 20 years after traumatic brain injury

The study describes functional outcomes and health‐related quality of life (HRQL) in patients with traumatic brain injury (TBI) 20 years postinjury.

Symptoms at 2 Months after Mild TBI: are they Related to Brain Injury? The Results of a Cluster Analysis

Objective: This study sought to explore whether subgroups of patients with mild TBI could be identified by their symptom profile according to cluster analysis. We also investigated whether these clusters are uniquely associated with structural brain damage as well as their relationship to anxiety and depression, other health complaints, functioning and participation in work. Methods: This was a prospective cohort study of patients with mild TBI who were registered at baseline and 6-8 weeks after injury. Results: A total of 270 patients were included. K-mean cluster analyses were conducted to describe groups of subjects with similar profiles of responses to the Rivermead Post Concussion Symptoms Questionnaire (RPQ). The four-cluster solution revealed one cluster with a low level of symptoms (low), one with a generally high symptom level (high), one cluster characterised by a high level of symptoms regarding cognitive functions (cognitive) and one cluster with somatic and frustration dominating symptoms (somatic). No significant differences in symptom level (mean score on RPQ) were revealed between subjects with and without radiological findings on brain scans (p=0.34). The “high” cluster group scored significantly higher than clusters 1, 2 and 3 in terms of both depression and anxiety but significantly lower on the GOSE. Cluster 2 scored significantly lower for health complaints in comparison to the other clusters. Conclusion: Subgroups of patients with mild TBI could be identified according to their symptom profile using cluster analysis. Patients with minor symptoms had a reduced risk for a positive finding on CT or MRI, whereas the high symptom level group struggled to return to work and demonstrated high levels of anxiety, depression and disability.

White matter microstructure is associated with functional, cognitive and emotional symptoms 12 months after mild traumatic brain injury

Identifying patients at risk of poor outcome after mild traumatic brain injury (MTBI) is essential to aid prognostics and treatment. Diffuse axonal injury (DAI) may be the primary pathologic feature of MTBI but is normally not detectable by conventional imaging technology. This lack of sensitivity of clinical imaging techniques has impeded a pathophysiologic understanding of the long-term cognitive and emotional consequences of MTBI, which often remain unnoticed and are attributed to factors other than the injury. Diffusion tensor imaging (DTI) is sensitive to microstructural properties of brain tissue and has been suggested to be a promising candidate for the detection of DAI in vivo. In this study, we report strong associations between brain white matter DTI and self-reported cognitive, somatic and emotional symptoms at 12 months post-injury in 134 MTBI patients. The anatomical distribution suggested global associations, in line with the diffuse symptomatology, although the strongest effects were found in frontal regions including the genu of the corpus callosum and the forceps minor. These findings support the hypothesis that DTI may provide increased sensitivity to the diffuse pathophysiology of MTBI and suggest an important role of advanced Magnetic Resonance Imaging (MRI) in trauma care.