Labour market attachment after mild traumatic brain injury: nationwide cohort study with 5-year register follow-up in Denmark

Return to work in persons with persistent postconcussion symptoms: a survey study examining the perspectives of employees and managers

OBJECTIVE

To examine challenges in return to work (RTW) for persons with persistent postconcussion symptoms (PPCS) experienced by the affected employees and their managers.

METHODS

A survey of employees (S-E) and two surveys of managers (S-M1, S-M2) executed 4 months apart to capture the time perspective. Inclusion: Adults aged 18-66 with PPCS > 4 weeks, employed at the time of mTBI who returned to work within the previous year. Managers involved in their RTW process.

OUTCOME MEASURES

Work status, working hours, work functioning (Work Role Functioning Questionnaire, WRFQ), work productivity.

RESULTS

Ninety-two employees and 66 managers were recruited. Three-fourths of the employees had returned to work but only one-third worked under similar conditions. Weekly working hours decreased from 36,3 hours (SD = 10,5) before mTBI to 17,6 hours (SD = 9,7). Employees had difficulties with tasks 43% of time (WRFQ). They needed more breaks, struggled with multitasking and work speed. About 65.9% experienced affected work productivity. Managers reported lack of knowledge and difficulties assessing the number of working hours and suitable tasks.

CONCLUSIONS

Most employees returned to work but only a minority worked under similar conditions as before mTBI. Employees and managers struggled to estimate workload. The affected employees and their workplaces need a long-term RTW support.

Effectiveness of personalized rehabilitation in adults suffering from persistent concussion symptoms as compared to usual care: a randomized control trial protocol

BACKGROUND

Symptoms reported by patients who sustain a concussion are non-specific. As such, clinicians are better able to manage patients when a standardized clinical exam is performed to sub-type the driver(s) of symptoms. Aerobic exercise and multimodal rehabilitation have consistently shown to be a possibly effective means to manage this population; however, the optimal training prescription is unclear. Thus, there is a need to further examine the effectiveness of personalized rehabilitative treatments. Our primary aim is to evaluate the response to personalized therapy on recovery, as measured by The Rivermead Post-concussion Symptoms Questionnaire (RPQ) when compared to an active control.

METHODS

We will conduct a multi-center 12-week case-crossover randomized controlled trial. 50 participants will be recruited from out-patient University Health Network clinics and community-based clinical practices around the greater Toronto area. Participants will be randomized at baseline to Group A: a personalized care program followed by an active control or Group B: an active control followed by a personalized care program. Participants will be included should they be 21 years of age and older and have symptoms that have persisted beyond 4 weeks but less than 1 year. Participants will undergo 6-weeks of care in their respective streams. After 6-weeks, participants will undergo a re-examination. They will then crossover and undertake the alternative treatment for 6 weeks. At the end of 12 weeks, participants will undertake the endpoint examinations. The primary outcome will be the Rivermead Postconcussion Questionnaire (RPQ). The secondary outcomes will be changes in standardized clinical examination, Neck Disability Index (NDI), Patient Health Questionnaire (PHQ-9) and an electroencephalography (EEG) via NeuroCatch™. The statistical analysis to be performed is composed of an adjusted model using an analysis of variance, specifically using an unpaired t-test to test for associations between variables and outcomes.

DISCUSSION

Given the recommendations from reviews on the topic of rehabilitation for adults with persistent concussion symptoms, we are undertaking a controlled trial. The documented high costs for patients seeking care for persistent symptoms necessitate the need to evaluate the effectiveness of a personalized rehabilitative program compared to the current standard of care.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT06069700.

Traumatic brain injury and occupational risk of low-level blast exposure on adverse career outcomes: an examination of administrative and medical separations from Service (2005-2015)

Introduction

Although traumatic brain injury (TBI) has been linked with adverse long-term health, less research has examined whether TBI is linked with non-clinical outcomes including involuntary job loss. Symptoms associated with TBI may influence one's ability to maintain gainful employment including employment in the U.S. military. That influence may impact military service members with exposure to repetitive low-level blast (LLB). Understanding the association between TBI and involuntary job loss outcomes among military populations is particularly important as it may be associated with differences in eligibility for post-service benefits. The purpose of the present research was to determine whether (1) TBI and related conditions are associated with involuntary job loss (i.e., medical and administrative separations from service) among military personnel, and (2) occupational risk of LLB is associated with involuntary job loss in both the presence and absence of clinical diagnoses of TBI and related conditions.

Method

This research leveraged population-level data from the Career History Archival Medical and Personnel System for enlisted personnel who served on active duty between 2005-2015. Risk of LLB exposure was categorized using military occupational specialty as a proxy. Medical diagnoses were identified using ICD-9 codes. Separations for medical and administrative reasons were identified.

Results

Risk for administrative separation differed across medical diagnoses of interest, but those who worked in high-risk occupations were more likely to be administratively separated than those working in low-risk occupations. Risk for medical separation was associated with occupational risk of LLB and each of the diagnoses of interest, though significant interactions suggested that the effects of certain diagnoses of interest (e.g., concussion, cognitive problems, postconcussive syndrome, migraines) on medical separations was greater among those working in high-risk occupations.

Discussion

Taken together, the present research suggests that TBI and associated medical conditions, as well as occupational risk of LLB, are associated with long-term involuntary job loss for medical reasons. This study is the first to demonstrate involuntary military job loss outcomes associated with TBI, mental health conditions, and conditions associated with blast exposure using both inpatient and outpatient population-level data and may have important implications for civilian employment and post-service benefits.

Labour market attachment dynamics in patients with concussion: a Danish nationwide register-based cohort study

BACKGROUND

Concussion may lead to persisting post-concussive symptoms affecting work ability and employment. This study examined the transitions between labour market states an individual can experience after the acute phase of concussion. The aim was to describe the incidence of favourable and adverse transitions between different labour market states (e.g., employment, sick leave) in relation to socioeconomic and health characteristics in individuals with concussion relative to matched controls.

METHODS

This Danish nationwide register-based cohort study extracted 18-60-year-old individuals between 2003-2007 with concussion from the Danish National Patient Register (ICD-10 S06.0). Controls were matched on age, sex, and municipality. Patients and controls were followed for 5 years starting three months after injury. Exclusion criteria were neurological injuries and unavailability to the labour market in the inclusion period (2003-2007) and 5-years before injury (1998-2002). Labour market states were defined from transfer income data in the Danish Register for Evaluation of Marginalization. Incidence rates of transitions between these labour market states were analysed in multistate models. Transitions were bundled in favourable and adverse transitions between labour market states and the difference in incidence rates between individuals with concussion relative to matched controls were assessed with hazard ratios from Cox regression models.

RESULTS

Persons with concussion (n = 15.580) had a lower incidence of favourable transitions (HR 0.88, CI 0.86-0.90) and a higher incidence of adverse transitions (HR 1.30, CI 1.27-1.35), relative to matched controls (n = 16.377). The effect of concussion differed depending on health and socioeconomic characteristics. Notably, individuals between 30-39 years (HR 0.83, CI 0.79-0.87), individuals with high-income (200.000-300.000 DKK) (HR 0.83, CI 0.80-0.87), and wage earners with management experience (HR 0.60, CI 0.44-0.81) had a markedly lower incidence of favourable transitions compared to controls. Additionally, individuals with high income also had a higher incidence of adverse transitions (HR 1.46, CI 1.34-1.58) compared to controls.

CONCLUSIONS

Concussion was associated with enhanced risk of adverse transitions between labour market states and lower occurrence of favourable transitions, indicating work disability, potentially due to persistent post-concussive symptoms. Some age groups, individuals with high income, and employees with management experience may be more affected.

Multidisciplinary interventions increase weekly working hours and quality of life in persons with post-concussion syndrome

OBJECTIVES

To improve labor market attachment, general health and quality of life in persons suffering from post-concussion syndrome. Labor market attachment often changes after mTBI, and especially in persons suffering from post-concussion syndrome, and constitutes a huge societal burden.

METHODS

Eighty-two adults with persistent post-concussion syndrome participated in this single-center and uncontrolled interventional efficacy open-label investigation. The primary endpoint was to increase weekly working hours. Outcome measures ranged from self-reported cognitive symptoms to objective performance testing. Multidisciplinary interventions were used to reduce symptoms of fatigue, stress, pain, oculomotor malfunction, and sensitivity to both sound and light.

RESULTS

Workhours improved from median 0 to 6 hours (p = 0.00002). Several significant improvements were observed in quality of life measured by the SF-36. General fatigue measured by the MFI-20 was reduced (p < 0.0001), and symptoms of depression were reduced (p < 0.0001). The COPM results were improved for task completion satisfaction and for ability to perform a task (p < 0.0001). Reading speed, and performances in the Groffman Visual Tracing Test and the King-Devick Test, all improved (p < 0.01). The intervention did not reduce perception of pain intensity (p = 0.11).

CONCLUSION

After the intervention, participants increased weekly workhours and improved in many aspects of life - including quality of life, performance in everyday activities, fatigue and depression. Perception of pain intensity was not improved.

Inflammatory cytokines associated with mild traumatic brain injury and clinical outcomes: a systematic review and meta-analysis

Mild traumatic brain injuries (mTBIs) trigger a neuroinflammatory response, which leads to perturbations in the levels of inflammatory cytokines, resulting in a distinctive profile. A systematic review and meta-analysis were conducted to synthesize data related to levels of inflammatory cytokines in patients with mTBI. The electronic databases EMBASE, MEDLINE, and PUBMED were searched from January 2014 to December 12, 2021. A total of 5,138 articles were screened using a systematic approach based on the PRISMA and R-AMSTAR guidelines. Of these articles, 174 were selected for full-text review and 26 were included in the final analysis. The results of this study demonstrate that within 24 hours, patients with mTBI have significantly higher levels of Interleukin-6 (IL-6), Interleukin-1 Receptor Antagonist (IL-1RA), and Interferon-γ (IFN-γ) in blood, compared to healthy controls in majority of the included studies. Similarly one week following the injury, patients with mTBI have higher circulatory levels of Monocyte Chemoattractant Protein-1/C-C Motif Chemokine Ligand 2 (MCP-1/CCL2), compared to healthy controls in majority of the included studies. The results of the meta-analysis also confirmed these findings by demonstrating significantly elevated blood levels of IL-6, MCP-1/CCL2, and Interleukin-1 beta (IL-1β) in the mTBI population compared to healthy controls (p < 0.0001), particularly in the acute stages (<7 days). Furthermore, it was found that IL-6, Tumor Necrosis Factor-alpha (TNF-α), IL-1RA, IL-10, and MCP-1/CCL2 were associated with poor clinical outcomes following the mTBI. Finally, this research highlights the lack of consensus in the methodology of mTBI studies that measure inflammatory cytokines in the blood, and also provides direction for future mTBI research.

A Digital Health Intervention for Concussion: Development and Clinical Feasibility Study

BACKGROUND

Concussion is a common condition that can lead to a constellation of symptoms that affect quality of life, social integration, and return to work. There are several evidence-based behavioral and psychological interventions that have been found to improve postconcussion symptom burden. However, these are not routinely delivered, and individuals receive limited support during their concussion recovery.

OBJECTIVE

This study aimed to develop and test the feasibility of a digital health intervention using a systematic evidence-, theory-, and person-based approach.

METHODS

This was a mixed methodology study involving a scoping review (n=21), behavioral analysis, and logic model to inform the intervention design and content. During development, the intervention was optimized with feedback from individuals who had experienced concussions (n=12) and health care professionals (n=11). The intervention was then offered to patients presenting to the emergency department with a concussion (n=50). Participants used the intervention freely and input symptom data as part of the program. A number of outcome measures were obtained, including participant engagement with the intervention, postconcussion symptom burden, and attitudes toward the intervention. A selection of participants (n=15) took part in in-depth qualitative interviews to understand their attitudes toward the intervention and how to improve it.

RESULTS

Engagement with the intervention functionality was 90% (45/50) for the symptom diary, 62% (31/50) for sleep time setting, 56% (28/50) for the alcohol tracker, 48% (24/50) for exercise day setting, 34% (17/50) for the thought diary, and 32% (16/50) for the goal setter. Metrics indicated high levels of early engagement that trailed off throughout the course of the intervention, with an average daily completion rate of the symptom diary of 28.23% (494/1750). A quarter of the study participants (13/50, 26%) were classified as high engagers who interacted with all the functionalities within the intervention. Quantitative and qualitative feedback indicated a high level of usability and positive perception of the intervention. Daily symptom diaries (n=494) demonstrated a wide variation in individual participant symptom burden but a decline in average burden over time. For participants with Rivermead scores on completion of HeadOn, there was a strong positive correlation (r=0.86; P<.001) between their average daily HeadOn symptom diary score and their end-of-program Rivermead score. Insights from the interviews were then fed back into development to optimize the intervention and facilitate engagement.

CONCLUSIONS

Using this systematic approach, we developed a digital health intervention for individuals who have experienced a concussion that is designed to facilitate positive behavior change. Symptom data input as part of the intervention provided insights into postconcussion symptom burden and recovery trajectories.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05069948; https://clinicaltrials.gov/ct2/show/NCT05069948.

Labour market participation after spinal cord injury. A register-based cohort study

STUDY DESIGN

A register based cohort study.

OBJECTIVES

To investigate labour market participation following spinal cord injury (SCI) and to describe the impact of personal and SCI characteristics.

SETTING

Norway.

METHODS

Persons registered with SCI in the Norwegian SCI registry 2011-2017, and matched reference individuals without SCI from the general population (named controls) were followed for up to six years after injury using national registry data on employment, education, income, and social security benefits. Main measures of labour market participation were: (1) Receiving any amount of pay for work, and (2) Receiving sickness and disability benefits.

RESULTS

Among the 451 persons with SCI (aged 16-66 years and working before injury), the estimated percentages receiving pay for work and sickness and disability benefits in the sixth years after injury were 63% (95% CI 57-69) and 67% (95% CI 61-72). Corresponding percentages for the controls (n = 1791) were 91% (95% CI 90-93) for receiving pay for work and 13% (95% CI 12-15) for receiving sickness and disability benefits. Among persons with SCI, less severe neurological outcome, higher level of education, younger age at injury, and a stronger pre-injury attachment to employment (higher employment income, having an employer, less receipt of benefits), were associated with higher labour market participation.

CONCLUSION

SCI substantially decreased labour market participation up to six years after injury compared to matched controls. Even if a relatively large proportion of persons with SCI remained in some degree of work activity, more than half did so in combination with receiving benefits.

Relationship between psychosocial and psychiatric risk factors and poor long-term outcome following mild traumatic brain injury: A systematic review

BACKGROUND AND PURPOSE

Mild traumatic brain injury (mTBI) has an estimated worldwide incidence of >60 million per year, and long-term persistent postconcussion symptoms (PPCS) are increasingly recognized as being predicted by psychosocial variables. Patients at risk for PPCS may be amenable to closer follow-up to treat modifiable symptoms and prevent chronicity. In this regard, similarities seem to exist with psychosocial risk factors for chronicity in other health-related conditions. However, as opposed to other conditions, no screening instruments exist for mTBI.

METHODS

A systematic search of the literature on psychological and psychiatric predictors of long-term symptoms in mTBI was performed by two independent reviewers using PubMed, Embase, and Web of Science.

RESULTS

Fifty papers were included in the systematic analysis. Anxiety, depressive symptoms, and emotional distress early after injury predict PPCS burden and functional outcome up to 1 year after injury. In addition, coping styles and preinjury psychiatric disorders and mental health also correlate with PPCS burden and functional outcome. Associations between PPCS and personality and beliefs were reported, but either these effects were small or evidence was limited.

CONCLUSIONS

Early psychological and psychiatric factors may negatively interact with recovery potential to increase the risk of chronicity of PPCS burden after mTBI. This opens opportunities for research on screening tools and early intervention in patients at risk.

Rehabilitation and outcomes after complicated vs uncomplicated mild TBI: results from the CENTER-TBI study

BACKGROUND

Despite existing guidelines for managing mild traumatic brain injury (mTBI), evidence-based treatments are still scarce and large-scale studies on the provision and impact of specific rehabilitation services are needed. This study aimed to describe the provision of rehabilitation to patients after complicated and uncomplicated mTBI and investigate factors associated with functional outcome, symptom burden, and TBI-specific health-related quality of life (HRQOL) up to six months after injury.

METHODS

Patients (n = 1379) with mTBI from the Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI) study who reported whether they received rehabilitation services during the first six months post-injury and who participated in outcome assessments were included. Functional outcome was measured with the Glasgow Outcome Scale - Extended (GOSE), symptom burden with the Rivermead Post Concussion Symptoms Questionnaire (RPQ), and HRQOL with the Quality of Life after Brain Injury - Overall Scale (QOLIBRI-OS). We examined whether transition of care (TOC) pathways, receiving rehabilitation services, sociodemographic (incl. geographic), premorbid, and injury-related factors were associated with outcomes using regression models. For easy comparison, we estimated ordinal regression models for all outcomes where the scores were classified based on quantiles.

RESULTS

Overall, 43% of patients with complicated and 20% with uncomplicated mTBI reported receiving rehabilitation services, primarily in physical and cognitive domains. Patients with complicated mTBI had lower functional level, higher symptom burden, and lower HRQOL compared to uncomplicated mTBI. Rehabilitation services at three or six months and a higher number of TOC were associated with unfavorable outcomes in all models, in addition to pre-morbid psychiatric problems. Being male and having more than 13 years of education was associated with more favorable outcomes. Sustaining major trauma was associated with unfavorable GOSE outcome, whereas living in Southern and Eastern European regions was associated with lower HRQOL.

CONCLUSIONS

Patients with complicated mTBI reported more unfavorable outcomes and received rehabilitation services more frequently. Receiving rehabilitation services and higher number of care transitions were indicators of injury severity and associated with unfavorable outcomes. The findings should be interpreted carefully and validated in future studies as we applied a novel analytic approach.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02210221.

Interdisciplinary intervention (GAIN) for adults with post-concussion symptoms: a study protocol for a stepped-wedge cluster randomised trial

Background

Persistent post-concussion symptoms (PCS) are associated with prolonged disability, reduced health-related quality of life and reduced workability. At present, no strong evidence for treatments for people with persistent PCS exists. Our research group developed a novel intervention, “Get going After concussIoN (GAIN)”, that incorporates multiple evidence-based strategies including prescribed exercise, cognitive behavioural therapy, and gradual return to activity advice. In a previous randomised trial, GAIN provided in a hospital setting was effective in reducing symptoms in 15–30-year-olds with PCS 2–6 months post-injury. In the current study, we describe the protocol for a trial designed to test the effectiveness of GAIN in a larger municipality setting. Additionally, we test the intervention within a broader age group and evaluate a broader range of outcomes. The primary hypothesis is that participants allocated to enhanced usual care plus GAIN report a higher reduction in PCS 3 months post-intervention compared to participants allocated to enhanced usual care only.

Methods

The study is a stepped-wedge cluster-randomised trial with five clusters. The 8-week interdisciplinary GAIN program will be rolled out to clusters in 3-month intervals. Power calculation yield at least 180 participants to be enrolled. Primary outcome is mean change in PCS measured by the Rivermead Post-Concussion Symptoms Questionnaire from enrolment to 3 months after end of treatment. Secondary outcomes include participation in and satisfaction with everyday activities, labour market attachment and other behavioural measures. Self-reported outcomes are measured at baseline, by end of treatment and at 3, 6, and 18 months after end of treatment. Registry-based outcomes are measured up to 36 months after concussion.

Discussion

The trial will provide important information concerning the effectiveness of the GAIN intervention in a municipality setting. Furthermore, it will provide knowledge of possible barriers and facilitators that may be relevant for future implementation of GAIN in different settings.

Trial registration

The current GAIN trial is registered in ClinicalTrials.gov (study identifier: NCT04798885) on 20 October 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06572-7.

Associations between Multimorbidity Patterns and Subsequent Labor Market Marginalization among Refugees and Swedish-Born Young Adults-A Nationwide Registered-Based Cohort Study

Background: Young refugees are at increased risk of labor market marginalization (LMM). We sought to examine whether the association of multimorbidity patterns and LMM differs in refugee youth compared to Swedish-born youth and identify the diagnostic groups driving this association. Methodology: We analyzed 249,245 individuals between 20–25 years, on 31 December 2011, from a combined Swedish registry. Refugees were matched 1:5 to Swedish-born youth. A multimorbidity score was computed from a network of disease co-occurrences in 2009–2011. LMM was defined as disability pension (DP) or >180 days of unemployment during 2012–2016. Relative risks (RR) of LMM were calculated for 114 diagnostic groups (2009–2011). The odds of LMM as a function of multimorbidity score were estimated using logistic regression. Results: 2841 (1.1%) individuals received DP and 16,323 (6.5%) experienced >180 annual days of unemployment during follow-up. Refugee youth had a marginally higher risk of DP (OR (95% CI): 1.59 (1.52, 1.67)) depending on their multimorbidity score compared to Swedish-born youth (OR (95% CI): 1.51 (1.48, 1.54)); no differences were found for unemployment (OR (95% CI): 1.15 (1.12, 1.17), 1.12 (1.10, 1.14), respectively). Diabetes mellitus and influenza/pneumonia elevated RR of DP in refugees (RRs (95% CI) 2.4 (1.02, 5.6) and 1.75 (0.88, 3.45), respectively); most diagnostic groups were associated with a higher risk for unemployment in refugees. Conclusion: Multimorbidity related similarly to LMM in refugees and Swedish-born youth, but different diagnoses drove these associations. Targeted prevention, screening, and early intervention strategies towards specific diagnoses may effectively reduce LMM in young adult refugees.

Self-Rated Executive Function and Health-Related Quality of Life in Young Adults With Persistent Post-Concussion Symptoms: A Cross-Sectional Study

OBJECTIVE

To assess self-reported executive dysfunction in young adult patients with persistent post-concussion symptoms (PCS) 2-6 months post-injury, and the association with self-reported Health-Related Quality of Life (HRQoL).

METHOD

This cross-sectional study carried out in a hospital setting was a secondary analysis of data from a separate randomized trial testing the effect of a novel intervention, "Get going After concussIoN " (GAIN), for persistent PCS. Patients (18-30 years) were recruited from a clinical cohort of patients with a hospital diagnosis of concussion or referred by primary care physicians. Main measures were The Behaviour Rating Inventory of Executive Function-Adult Version providing two index scores, that is, the Metacognitive Index (MI) and the Behavioural Regulation Index (BRI), and the Quality of Life after Brain Injury-Overall Scale.

RESULTS

Compared with normative data, patients had elevated scores (i.e., worse functioning) on both the MI and the BRI. In linear regression analysis, the MI score, but not the BRI score, was negatively associated with self-reported HRQoL (MI: slope = -.27, 95% confidence interval, CI [-.53, -.02], p = .03; BRI: slope = -.19, 95% CI [-.49, .13], p = .24), suggesting a positive association of subjective executive dysfunction and lower HRQoL. However, the association was attenuated after adjustment for self-reported psychological distress (MI: slope = -.09, 95% CI [-.34, .17], p = .51).

CONCLUSION

Self-reported executive dysfunction is common in young adult patients with persistent PCS, but not strongly associated with decreased HRQoL after adjusting for concurrent psychological distress.

Nonpharmacological Treatment of Persistent Postconcussion Symptoms in Adults: A Systematic Review and Meta-analysis and Guideline Recommendation

IMPORTANCE

Persistent (>4 weeks) postconcussion symptoms (PPCS) are challenging for both patients and clinicians. There is uncertainty about the effect of commonly applied nonpharmacological treatments for the management of PPCS.

OBJECTIVE

To systematically assess and summarize evidence for outcomes related to 7 nonpharmacological interventions for PPCS in adults (aged >18 years) and provide recommendations for clinical practice.

DATA SOURCES

Systematic literature searches were performed via Embase, MEDLINE, PsycINFO, CINAHL, PEDro, OTseeker, and Cochrane Reviews (via MEDLINE and Embase) from earliest possible publication year to March 3, 2020. The literature was searched for prior systematic reviews and primary studies. To be included, studies had to be intervention studies with a control group and focus on PPCS.

STUDY SELECTION

A multidisciplinary guideline panel selected interventions based on frequency of use and need for decision support among clinicians, including early information and advice, graded physical exercise, vestibular rehabilitation, manual treatment of neck and back, oculomotor vision treatment, psychological treatment, and interdisciplinary coordinated rehabilitative treatment. To be included, studies had to be intervention studies within the areas of the predefined clinical questions, include a control group, and focus on symptoms after concussion or mild traumatic brain injury.

DATA EXTRACTION AND SYNTHESIS

Extraction was performed independently by multiple observers. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used for data abstraction and data quality assessment. Included studies were assessed using the Assessment of Multiple Systematic Reviews (AMSTAR) tool and the Cochrane Risk of Bias (randomized clinical trials) tool. Meta-analysis was performed for all interventions where possible. Random-effects models were used to calculate pooled estimates of effects. The level and certainty of evidence was rated and recommendations formulated according to the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework.

MAIN OUTCOMES AND MEASURES

All outcomes were planned before data collection began according to a specified protocol. The primary outcomes were the collective burden of PPCS and another outcome reflecting the focus of a particular intervention (eg, physical functioning after graded exercise intervention).

RESULTS

Eleven systematic reviews were identified but did not contribute any primary studies; 19 randomized clinical trials comprising 2007 participants (1064 women [53.0%]) were separately identified and included. Evidence for the 7 interventions ranged from no evidence meeting the inclusion criteria to very low and low levels of evidence. Recommendations were weak for early information and advice, graded physical exercise, vestibular rehabilitation, manual treatment of the neck and back, psychological treatment, and interdisciplinary coordinated rehabilitative treatment. No relevant evidence was identified for oculomotor vision treatment, so the panel provided a good clinical practice recommendation based on consensus.

CONCLUSIONS AND RELEVANCE

Based on very low to low certainty of evidence or based on consensus, the guideline panel found weak scientific support for commonly applied nonpharmacological interventions to treat PPCS. Results align with recommendations in international guidelines. Intensified research into all types of intervention for PPCS is needed.

Adenosine A3 receptor as a novel therapeutic target to reduce secondary events and improve neurocognitive functions following traumatic brain injury

Background

Traumatic brain injury (TBI) is a common pathological condition that presently lacks a specific pharmacological treatment. Adenosine levels rise following TBI, which is thought to be neuroprotective against secondary brain injury. Evidence from stroke and inflammatory disease models suggests that adenosine signaling through the G protein-coupled A₃ adenosine receptor (A₃AR) can provide antiinflammatory and neuroprotective effects. However, the role of A₃AR in TBI has not been investigated.

Methods

Using the selective A₃AR agonist, MRS5980, we evaluated the effects of A₃AR activation on the pathological outcomes and cognitive function in CD1 male mouse models of TBI.

Results

When measured 24 h after controlled cortical impact (CCI) TBI, male mice treated with intraperitoneal injections of MRS5980 (1 mg/kg) had reduced secondary tissue injury and brain infarction than vehicle-treated mice with TBI. These effects were associated with attenuated neuroinflammation marked by reduced activation of nuclear factor of kappa light polypeptide gene enhancer in B cells (NFκB) and MAPK (p38 and extracellular signal-regulated kinase (ERK)) pathways and downstream NOD-like receptor pyrin domain-containing 3 inflammasome activation. MRS5980 also attenuated TBI-induced CD4⁺ and CD8⁺ T cell influx. Moreover, when measured 4–5 weeks after closed head weight-drop TBI, male mice treated with MRS5980 (1 mg/kg) performed significantly better in novel object-placement retention tests (NOPRT) and T maze trials than untreated mice with TBI without altered locomotor activity or increased anxiety.

Conclusion

Our results provide support for the beneficial effects of small molecule A₃AR agonists to mitigate secondary tissue injury and cognitive impairment following TBI.

Effect of concussion on salary and employment: a population-based event time study using a quasi-experimental design

OBJECTIVE

Concussions are the most frequent traumatic brain injuries. Yet, the socioeconomic impact of concussions remains unclear. Socioeconomic effects of concussions on working-age adults were studied on a population scale.

DESIGN

This population-based, event time study uses administrative data as well as hospital and emergency room records for the population of Denmark.

SETTING

We study all Danish patients, aged 20-59 years, who were treated at a public hospital or at an emergency room between 2003 and 2017 after suffering a concussion without other intracranial or extracranial injuries (n=55 424 unique individuals). None of the patients had a prior diagnosis of intracranial or extracranial injuries within the past 10 years leading up to the incident.

PRIMARY AND SECONDARY OUTCOME MEASURES

As primary endpoint, we investigate the mean effect of concussion on annual salaried income within a 5-year period after trauma. In an exploratory analysis, we study whether the potential impact of concussion on annual salaried income is driven by patient age, education or economic cycle.

RESULTS

Concussion was associated with an average change in annual salary income of -€1223 (95% CI: -€1540 to -905, p<0.001) corresponding to a salary change of -4.2% (95% CI: -5.2% to -3.1 %). People between 30 and 39 years and those without high school degrees suffered the largest salary decreases. Affected individuals leaving the workforce drove the main part of the decrease. Absolute annual effect sizes were countercyclical to the unemployment rate.

CONCLUSIONS

Concussions have a large and long-lasting impact on salary and employment of working-age adults on a nationwide scale.

Facilitators of and barriers to return to work after mild traumatic brain injury: A thematic analysis

Individuals with mild traumatic brain injury (mTBI) may experience protracted symptoms affecting their ability to work. Several actors may facilitate or act as a barrier to a successful return to work (RTW). This qualitative study used semi-structured in-depth interviews with 22 adults with mTBI at 2-5 years post injury, targeting experiences of how different actors facilitated or acted as a barrier in the RTW process, and encompassed the mTBI trajectory from the acute phase to the post-acute phase. A thematic analysis with a hermeneutical phenomenological approach was used to analyse data. Three main themes emerged. (1) Worker-employer relationship: Workplace accommodations such as decreased working hours, modified working conditions, and support from co-workers were lacking. (2) The role of the general practitioner: The general practitioner was lacking treatment and referral opportunities and failed to provide the patient with relevant and individualized guidance. (3) Municipal case management: Participants perceived being met with distrust by social workers, follow-up assessments were too frequent, unnecessary, and did not target concussion, and rehabilitation was referred too late. Clinical practice guidelines to improve referral to relevant concussion rehabilitation in case of persistent symptoms are needed to inform clinicians, employers, and public institutions to facilitate a successful RTW.

A Scoping Review of Registered Clinical Studies on Mild Traumatic Brain Injury and Concussion (2000 to 2019)

BACKGROUND

While many patients with mild traumatic brain injury (mTBI) or concussion recover completely, prolonged postconcussion symptoms remain a challenge for patients and an opportunity for clinical research. This has led to numerous research initiatives over the last 2 decades.

OBJECTIVE

To review the characteristics of clinical studies on management of mTBI/concussion; and to examine their definitions of mTBI/concussion.

METHODS

This scoping review included all clinical studies on diagnosis and management of patients with mTBI/concussion registered at www.clinicaltrials.gov from 2000 to June/2019. The terms “mild TBI/concussion” were used for the primary search. Definitions of mTBI/concussion were obtained from the protocols. When a definition was missing in the website, the study's investigators were contacted for clarification.

RESULTS

There were 225 interventional and 95 observational studies. Most of the studies are focused on treatment (54.7%) or diagnosis (37.5%), while 3.4% examined preventive measures, 2.8% evaluated prognostic instruments, and 1.6% developed registries. Most of the studies in this American database were single-center initiatives led by American and Canadian institutions. The definitions of mTBI/concussion differed widely among 109 studies.

CONCLUSION

The results of this review suggest that most of the clinical studies are focused on diagnosis and non-pharmacological therapies for patients with mTBI/concussion. The large number of differing definitions of mTBI/concussion among the studies creates significant limitations when comparing studies. The requirements for registering research protocols on mTBI/concussion should include the necessity to state the definition being used. There is a need for consensus on a uniform definition of concussion.