Post-concussion Symptom Factors and Neuropsychological Outcomes in Collegiate Athletes

Examining the role of depression on the relationship between performance-based and self-reported cognitive functioning after sport-related concussion

OBJECTIVE

Little is known about the relationship between neuropsychological test performance, cognitive symptom reporting, and depressive symptoms after sport-related concussion. Accordingly, this cross-sectional study examined these relationships in collegiate athletes. It was hypothesized that depressive symptoms would moderate and mediate the relationship between performance-based and self-reported cognitive functioning after concussion.

METHODS

After sustaining a sport-related concussion, 110 collegiate athletes completed a neuropsychological battery, the Post-Concussion Symptoms Scale, and the Beck Depression Inventory-Fast Screen. Neuropsychological test performance, depressive symptoms, and their interactions were entered into distinct hierarchical linear regression analyses with self-reported cognition as the dependent variable to assess moderation. Mediation was analyzed using the PROCESS macro with 5000 bootstrap samples and a 95% confidence interval.

RESULTS

There was a significant interaction between the mean memory composite and depressive symptoms when predicting cognitive symptom reporting, p = 0.047. Simple effects tests revealed that for athletes who had a lower memory composite score, an increase in depressive symptoms led to an increase in self-reported cognitive dysfunction, p < 0.001, ηp2 = 0.11. Depressive symptoms partially mediated the relationship between the memory composite and cognitive symptom reporting, indirect effect = -0.26, 95%CI[-0.58,0.001], but this relationship was not found for any other neurocognitive domain.

CONCLUSIONS

For tests of memory, depressive symptoms moderated and partially mediated the relationship between performance-based and self-reported cognitive functioning after sport-related concussion. Athletes reporting high depressive symptoms and cognitive dysfunction may need more comprehensive evaluations to inform return-to-play decisions, and depression could be a treatment target for athletes who report high levels of cognitive dysfunction after concussion.

The association between symptom burden and processing speed and executive functioning at 4 and 12 weeks following pediatric concussion

OBJECTIVES

Symptoms and cognition are both utilized as indicators of recovery following pediatric concussion, yet their interrelationship is not well understood. This study aimed to investigate: 1) the association of post-concussion symptom burden and cognitive outcomes (processing speed and executive functioning [EF]) at 4 and 12 weeks after pediatric concussion, and 2) the moderating effect of sex on this association.

METHODS

This prospective, multicenter cohort study included participants aged 5.00-17.99 years with acute concussion presenting to four Emergency Departments of the Pediatric Emergency Research Canada network. Five processing speed and EF tasks and the Post-Concussion Symptom Inventory (PCSI; symptom burden, defined as the difference between post-injury and retrospective [pre-injury] scores) were administered at 4 and 12 weeks post-concussion. Generalized least squares models were conducted with task performances as dependent variables and PCSI and PCSI*sex interaction as the main predictors, with important pre-injury demographic and injury characteristics as covariates.

RESULTS

311 children (65.0% males; median age = 11.92 [IQR = 9.14-14.21 years]) were included in the analysis. After adjusting for covariates, higher symptom burden was associated with lower Backward Digit Span (χ2 = 9.85, p = .043) and Verbal Fluency scores (χ2 = 10.48, p = .033) across time points; these associations were not moderated by sex, ps ≥ .20. Symptom burden was not associated with performance on the Coding, Continuous Performance Test, and Color-Word Interference scores, ps ≥ .17.

CONCLUSIONS

Higher symptom burden is associated with lower working memory and cognitive flexibility following pediatric concussion, yet these associations were not moderated by sex. Findings may inform concussion management by emphasizing the importance of multifaceted assessments of EF.

Affective Disturbance and Neurocognitive Variability in College Athletes

OBJECTIVE

Research on the neurocognitive effects of comorbid mood/anxiety disturbance in college athletes is limited. Previous research found that athletes with comorbid depression/anxiety performed worse on measures of attention/processing speed (A/PS) at baseline compared to healthy controls. However, this work solely examined mean performance. The current study expands upon this work by examining intraindividual variability (IIV) in relation to affective disturbance.

METHOD

835 (M = 624, F = 211) collegiate athletes completed baseline neuropsychological testing. Athletes were separated into four groups (Healthy Mood [n = 582], Depression Alone [n = 137], Anxiety Alone [n = 54], and Co-Occurring Depression/Anxiety [n = 62]) based on self-reported anxiety and depression. IIV was examined globally and within composites of A/PS and memory via intraindividual standard deviation, with higher scores indicating greater variability.

RESULTS

Linear regression results revealed that the Co-Occurring Depression/Anxiety group exhibited greater variability within the memory composite compared to the Healthy Mood group, as well as the Depression Alone and Anxiety Alone groups. The Depression Alone and Anxiety Alone groups did not differ from the Healthy Mood group on memory IIV. None of the groups differed on A/PS or global IIV.

CONCLUSIONS

Athletes with co-occurring depression/anxiety demonstrated greater variability in performance on memory tasks. Greater dispersion is predictive of greater cognitive decline following concussion; therefore, it is important that neuropsychological performance is interpreted beyond measures of central tendency. These findings also highlight the importance of having baseline data available for athletes with affective disturbance, as these factors may influence performance, place athlete at risk for poorer outcomes, and skew future post-concussion comparisons.

Sleep/Wake Disorders After Sports Concussion: Risks, Revelations, and Interventions

SUMMARY

Sleep-wake disturbances (SWDs) are among the most prevalent, persistent, and often disregarded sequelae of traumatic brain injury. Identification and treatment of SWDs in patients with traumatic brain injury is important and can complement other efforts to promote maximum functional recovery. SWDs can accentuate other consequences of traumatic brain injury, negatively affect mood, exacerbate pain, heighten irritability, and diminish cognitive abilities and the potential for recovery. The risk for sports injuries increases when athletes are sleep deprived. Sleep deprivation increases risk-taking behaviors, predisposing to injuries. SWDs are an independent risk factor for prolonged recovery after sports-related concussion. SWDs following sports-related concussion have been shown to impede recovery, rehabilitation, and return to preinjury activities.

Beyond acute concussion assessment to office management: a systematic review informing the development of a Sport Concussion Office Assessment Tool (SCOAT6) for adults and children

OBJECTIVES

To systematically review the scientific literature regarding the assessment of sport-related concussion (SRC) in the subacute phase (3-30 days) and provide recommendations for developing a Sport Concussion Office Assessment Tool (SCOAT6).

DATA SOURCES

MEDLINE, Embase, PsycINFO, Cochrane CENTRAL, CINAHL, SPORTDiscus and Web of Science searched from 2001 to 2022. Data extracted included study design, population, definition of SRC diagnosis, outcome measure(s) and results.

ELIGIBILITY CRITERIA

(1) Original research, cohort studies, case-control studies, diagnostic accuracy and case series with samples >10; (2) SRC; (3) screening/technology that assessed SRC in the subacute period and (4) low risk of bias (ROB). ROB was performed using adapted Scottish Intercollegiate Guidelines Network criteria. Quality of evidence was evaluated using the Strength of Recommendation Taxonomy classification.

RESULTS

Of 9913 studies screened, 127 met inclusion, assessing 12 overlapping domains. Results were summarised narratively. Studies of acceptable (81) or high (2) quality were used to inform the SCOAT6, finding sufficient evidence for including the assessment of autonomic function, dual gait, vestibular ocular motor screening (VOMS) and mental health screening.

CONCLUSION

Current SRC tools have limited utility beyond 72 hours. Incorporation of a multimodal clinical assessment in the subacute phase of SRC may include symptom evaluation, orthostatic hypotension screen, verbal neurocognitive tests, cervical spine evaluation, neurological screen, Modified Balance Error Scoring System, single/dual task tandem gait, modified VOMS and provocative exercise tests. Screens for sleep disturbance, anxiety and depression are recommended. Studies to evaluate the psychometric properties, clinical feasibility in different environments and time frames are needed.

PROSPERO REGISTRATION NUMBER

CRD42020154787.

Relationship between subjective report and objective assessment of neurocognitive functioning in persons with multiple sclerosis

OBJECTIVE

Persons with multiple sclerosis (PwMS) are at increased risk for cognitive dysfunction. Considering the impact and potential ramifications of cognitive dysfunction, it is important that cognition is routinely assessed in PwMS. Thus, it is also important to identify a screener that is accurate and sensitive to MS-related cognitive difficulties, which can inform decisions for more resource-intensive neuropsychological testing. However, research focused on available self-report screeners has been mixed, such as with the Multiple Sclerosis Neuropsychological Screening Questionnaire (MSNQ). This study aims to clarify the relationship between subjective and objective assessment of cognitive functioning in MS by examining domain-specific performance and intraindividual variability (IIV).

METHODS

87 PwMS (F = 65, M = 22) completed a comprehensive neuropsychological battery which included self- and informant-report measures of neurocognitive functioning. Scores were examined in relation to mean performance on five domains of cognitive functioning and two measures of IIV.

RESULTS

The MSNQ-Self was inversely associated with executive function, verbal memory, and visual memory; it was not associated with IIV. The MSNQ-Informant was inversely associated with executive function and verbal memory, and positively associated with one measure of IIV. The MSNQ-Self showed a correlation of moderate effect size with depression (r = .39) while the MSNQ-Informant did not.

CONCLUSIONS

Results suggest that the MSNQ-Self and MSNQ-Informant show similar utility. Our findings also suggest that domains of executive function and memory may be most salient, thus more reflected in subjective reports of cognitive functioning. Future work should further examine the impact of mood disturbance with cognitive performance and IIV.

Postconcussion Symptoms and Neuropsychological Performance in Athletes: A Literature Review

ABSTRACT

Neuropsychological assessment is a common part of concussion evaluation and plays an important role within the context of a comprehensive multidisciplinary approach to managing sports-related concussion. A literature review has shown an assortment of cognitive domains used for evaluation of PCS with their corresponding tests. This review focuses on the various cognitive domains following single or multiple TBIs in athletes. Decreases in memory, executive function, language, psychomotor function, and self-reported cognitive function reached statistical significance in concussed athletes versus controls. Length of time since onset of symptoms correlated with worse memory function in chronic concussion athletes and more headache symptoms correlated with a worse outcome as well. However, some treatments are shown to be beneficial for restoration of cognitive function. When analyzing these results, it is imperative to be cognizant of the bias in the current literature. Further well-designed studies are needed to replicate these findings in larger more diverse samples.

Characterizing Symptoms Before and Following Concussion in Professional Hockey

OBJECTIVE

Examine SCAT5 baseline and acute symptom subscales in professional hockey players.

DESIGN

Longitudinal case-control.

SETTING

Preseason medical evaluations and suspected concussion evaluations.

PARTICIPANTS

NHL/AHL players were given the NHL-modified SCAT5 before the 2018-2019 season (n = 1924). During the season, English-speaking players evaluated within 1 day of injury and diagnosed with concussion (n = 140) were compared with players evaluated for possible concussion, but not given a concussion diagnosis (n = 174).

INDEPENDENT VARIABLES

Concussion diagnosis and demographic characteristics.

MAIN OUTCOME MEASURES

Postconcussion Symptoms Scale (PCSS) items were subdivided into affective/emotional, cognitive, somatic/physical, sleep, and headache subscales.

RESULTS

Cognitive (13%), somatic/physical (10%), sleep (26%), affective (18%), and headache (6%) symptoms were reported by players at baseline. Concussed players reported more acute symptoms than active controls on each of the subscales (all P's < 0.001). Players who underwent a suspected concussion evaluation were more likely to be diagnosed with concussion if they reported affective/emotional symptoms at baseline (P < 0.001). Postinjury cognitive (P < 0.001), somatic/physical (P < 0.001), and headache (P < 0.001) symptoms best differentiated concussed players and active controls.

CONCLUSIONS

Player reports of increased cognitive difficulties, somatic/physical difficulties, and headache were most associated with concussion diagnosis at the acute evaluation. An abbreviated "acute" PCSS that includes only headache, cognitive, and/or physical symptoms may be useful for diagnostic purposes when evaluation time is limited. Approximately 2% of players reported significantly elevated affective/emotional symptoms at baseline and report of affective/emotional symptoms at baseline was associated with an increased likelihood of concussion diagnosis among players referred for a suspected concussion evaluation.

Relationship Between Self-Reported Concomitant Depressive and Anxiety Symptoms and the Post-Concussion Symptoms Scale (PCSS)

OBJECTIVES

The current study explored how affective disturbances, particularly concomitant anxiety and depressive symptoms, impact baseline symptom self-reporting on the Post-Concussion Symptoms Scale (PCSS) in college athletes.

METHODS

Athletes were separated into four groups (Healthy Control (HC) (n = 581), Depression Only (n = 136), Anxiety Only (n = 54), Concomitant Depression/Anxiety (n = 62)) based on their anxiety and depression scores. Groups were compared on Total PCSS Score as well as 5 PCSS Symptom Cluster scores (Cognitive, Physical, Affective, Sleep, and Headache).

RESULTS

The three affective groups reported significantly greater symptomatology than HCs, with the Concomitant group showing the highest symptomatology scores across all clusters. The depressive symptoms only group also reported significantly elevated symptomatology, compared to HCs, on every symptom cluster except headache. The anxiety symptoms only group differed from HCs on only the cognitive symptoms cluster. Additionally, the Concomitant group reported significantly increased PCSS symptomatology, in terms of total scores and all 5 symptom clusters, compared to the depressive symptoms only and anxiety symptoms only groups.

CONCLUSIONS

Our findings suggest that athletes experiencing concomitant depressive/anxiety symptoms report significantly greater levels of symptomatology across all 5 PCSS symptom clusters compared to HCs. Further, results suggest that athletes experiencing concomitant affective disturbance tend to report greater symptomatology than those with only one affective disturbance. These findings are important because, despite the absence of concussion, the concomitant group demonstrated significantly elevated symptomatology at baseline. Thus, future comparisons with post-concussion data should account for this increased symptomatology, as test results may be skewed by affective disturbances at baseline.

No Association Between Processing Speed and Risk of Sport-Related Concussion in Youth Soccer

OBJECTIVE

To determine whether slow processing speed is associated with risk of sport-related concussion.

DESIGN

We conducted a retrospective cohort study using computerized neurocognitive assessments (Immediate Post-concussion Assessment and Cognitive Testing [ImPACT]) from the Massachusetts Concussion Management Coalition. Slow processing speed was defined as 2 SD below the sample mean (n = 131) and fast processing speed as 2 SD above the sample mean (n = 259). We used a binary logistic regression model to determine the odds of sustaining a concussion with our main predictor being processing speed (high or low) adjusted for the effects of age, sex, and prior number of concussions.

SETTING

Massachusetts Concussion Management Coalition, Institutional care.

PARTICIPANTS

Three hundred ninety junior high soccer players ages 10 to 15 with a baseline score for ImPACT.

INDEPENDENT VARIABLES

Processing Speed.

MAIN OUTCOME MEASURES

Risk of sustaining a concussion.

RESULTS

Those with slow processing speed had a visual motor composite score of ≤19.92, those with fast-processing speed had a score of ≥46.20. Athletes with slow processing speed were younger (13 vs 14 years; P < 0.001) and more likely to be male (57% vs 49%; P = 0.014). After adjusting for the effects of age, sex, and prior concussions, there was no significant difference in the odds of sustaining a concussion between groups (aOR 1.01; 95% CI, 0.99-1.04).

CONCLUSIONS

Despite previous research showing that slow processing speed is a risk factor for musculoskeletal injuries during sports, our study suggests that processing speed is not associated with the risk of sustaining a concussion among junior high school soccer players.

Effect of Sleep-Related Symptoms on Recovery From a Sport-Related Concussion

Background

Sleep issues are commonly reported in athletes after a sport-related concussion (SRC). Further studies are needed to evaluate screening methods for sleep disturbances and the risk of persisting symptoms after an SRC.

Purpose

To evaluate the association between the Sport Concussion Assessment Tool 5 (SCAT5) symptoms of trouble falling asleep, fatigue (or low energy), and drowsiness and the risk of persisting symptoms (≥28 days to recovery) in adolescent athletes.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 519 athletes aged 13 to 18 years reported any sleep-related symptoms with an SRC, scored as none (0), mild (1-2), moderate (3-4), or severe (5-6), at their initial office visit (median, 5.4 days after an SRC). Scores were correlated with the risk of persisting symptoms. A composite "sleep cluster" score (range, 0-18) was calculated by summing the SCAT5 component items for trouble falling asleep, fatigue, and drowsiness.

Results

The results indicated that, compared with athletes who reported that they did not have each symptom, (1) athletes who reported mild, moderate, or severe trouble falling asleep were 3.0, 4.6, and 6.7 times more likely to have persisting symptoms, respectively; (2) athletes reporting mild, moderate, or severe fatigue (or low energy) were 2.6, 4.8, and 7.6 times more likely to have persisting symptoms, respectively; and (3) athletes reporting mild, moderate, or severe drowsiness were 1.9, 4.6, and 6.8 times more likely to have persisting symptoms, respectively (P < .001 for all). For every 1-point increase in the sleep cluster score, there was a 1.2-fold increased risk of persisting symptoms and an additional 2.4 days of recovery required (P < .001 for both).

Conclusion

Athletes who reported mild, moderate, or severe sleep-related symptoms on the SCAT5 were at a proportionally increased risk of persisting symptoms at the initial office visit.

Recovery of symptoms, neurocognitive and vestibular-ocular-motor function and academic ability after sports-related concussion (SRC) in university-aged student-athletes: a systematic review

BACKGROUND

Physiological differences between a maturing and matured brain alters how Sports-Related Concussion (SRC) affects different age groups; therefore, a review specific to university-aged student-athletes is needed.

OBJECTIVES

Determine time to recovery for symptom burden, neurocognitive and Vestibular-Ocular-Motor (VOM) function and academic impact in university-aged student-athletes.

METHODS

Searches were conducted in PubMed, SpringerLink, PsycINFO, Science Direct, Scopus, Cochrane, Web of Science and EMBASE. Articles were included if they contained original data collected within 30 days in university-aged student-athletes, analysed SRC associated symptoms, neurocognitive or VOM function or academic ability and published in English. Two reviewers independently reviewed sources, using the Oxford Classification of Evidence-Based Medicine (CEBM) and the Downs and Black checklist, and independently extracting data before achieving consensus.

RESULTS

58 articles met the inclusion criteria. Recovery of symptoms occurred by 7 and 3-5.3 days for neurocognition. The evidence base did not allow for a conclusion on recovery time for VOM function or academic ability. Few papers investigated recovery times at specified re-assessment time-points and have used vastly differing methodologies.

CONCLUSIONS

To fully understand the implication of SRC on the university-aged student-athlete' studies using a multi-faceted approach at specific re-assessments time points are required.Systematic review registration number: CRD42019130685.

Paediatric post-concussive symptoms: symptom clusters and clinical phenotypes

OBJECTIVE

To assess the co-occurrence and clustering of post-concussive symptoms in children, and to identify distinct patient phenotypes based on symptom type and severity.

METHODS

We performed a secondary analysis of the prospective, multicentre Predicting and Preventing Post-concussive Problems in Pediatrics (5P) cohort study, evaluating children 5-17 years of age presenting within 48 hours of an acute concussion. Our primary outcome was the simultaneous occurrence of two or more persistent post-concussive symptoms on the Post-Concussion Symptom Inventory at 28 days post-injury. Analyses of symptom and patient clusters were performed using hierarchical cluster analyses of symptom severity ratings.

RESULTS

3063 patients from the parent 5P study were included. Median age was 12.1 years (IQR: 9.2-14.6 years), and 1857 (60.6%) were male. Fatigue was the most common persistent symptom (21.7%), with headache the most commonly reported co-occurring symptom among patients with fatigue (55%; 363/662). Headache was common in children reporting any of the 12 other symptoms (range: 54%-72%). Physical symptoms occurred in two distinct clusters: vestibular-ocular and headache. Emotional and cognitive symptoms occurred together more frequently and with higher severity than physical symptoms. Fatigue was more strongly associated with cognitive and emotional symptoms than physical symptoms. We identified five patient groups (resolved/minimal, mild, moderate, severe and profound) based on symptom type and severity.

CONCLUSION

Post-concussive symptoms in children occur in distinct clusters, facilitating the identification of distinct patient phenotypes based on symptom type and severity. Care of children post-concussion must be comprehensive, with systems designed to identify and treat distinct post-concussion phenotypes.While I agree with the use of the british spelling of Paediatric throughout, this groups actual name is with the American English Spelling.

Cognitive Impairment in Primary and Secondary Headache Disorders

Purpose of Review

To critically evaluate the recent literature on cognitive impairment and headache.

Recent Findings

Neurocognitive symptoms are prevalent, debilitating, and occur often with both primary and secondary headache disorders.

Summary

This is a “narrative review of the current literature in PubMed on cognitive function and headache.” Migraine is associated with cognitive impairment years before a migraine diagnosis. In young and middle-aged adults, migraine is associated with deficits in attention, executive function, processing speed, and memory. It is unlikely that migraine is associated with dementia. Although methodologically difficult to assess, there does not seem to be an association between tension-type headache and cognitive dysfunction. In early to midlife, cluster headache seems to be associated with executive dysfunction. Several secondary headache syndromes relevant to clinicians managing headache disorders are associated with poorer cognitive performance or distinctive cognitive patterns, including those attributed to chronic cerebral or systemic vascular disorders, trauma, and derangements of intracranial pressure and volume, including frontotemporal brain sagging syndrome.

Comorbid Affective Symptomatology and Neurocognitive Performance in College Athletes

OBJECTIVES

The current study aims to examine the prevalence rates and the relationship of symptoms of depression, anxiety, and comorbid depression/anxiety with neurocognitive performance in college athletes at baseline. We hypothesized a priori that the mood disturbance groups would perform worse than healthy controls, with the comorbid group performing worst overall.

METHODS

Eight hundred and thirty-one (M = 620, F = 211) collegiate athletes completed a comprehensive neuropsychological test battery at baseline which included self-report measures of anxiety and depression. Athletes were separated into four groups [Healthy Control (HC) (n = 578), Depressive Symptoms Only (n = 137), Anxiety Symptoms Only (n = 54), and Comorbid Depressive/Anxiety Symptoms (n = 62)] based on their anxiety and depression scores. Athletes' neurocognitive functioning was analyzed via Z score composites of Attention/Processing Speed and Memory.

RESULTS

One-way analysis of variance revealed that, compared to HC athletes, the comorbid group performed significantly worse on measures of Attention/Processing Speed but not Memory. However, those in the depressive symptoms only and anxiety symptoms only groups were not significantly different from one another or the HC group on neurocognitive outcomes. Chi-square analyses revealed that a significantly greater proportion of athletes in all three affective groups were neurocognitively impaired compared to the HC group.

CONCLUSIONS

These results demonstrate that collegiate athletes with comorbid depressive/anxiety symptoms should be identified, as their poorer cognitive performance at baseline could complicate post-concussion interpretation. Thus, assessing for mood disturbance at baseline is essential to obtain an accurate measurement of baseline functioning. Further, given the negative health outcomes associated with affective symptomatology, especially comorbidities, it is important to provide care as appropriate.

Symptom Factors and Neuropsychological Performance in Collegiate Athletes with Chronic Concussion Symptoms

OBJECTIVE

The present study explored the relationship between specific types of postconcussion symptoms and cognitive outcomes in student-athletes with chronic concussion symptoms.

METHOD

Forty student-athletes with chronic concussion symptoms were given a battery of neuropsychological tests and rated themselves on a variety of postconcussion symptoms, which included the following factors derived from prior work: Physical, Sleep, Cognitive, Affective, and Headache. Cognitive outcomes included performance on composites for the memory and attention/executive functioning speed tests, respectively. The following covariates were also explored: Sex, depression symptoms, number of previous concussions, and time since injury.

RESULTS

Headache was the only individual symptom factor that significantly (p < .05) predicted worse attention/executive functioning performance. None of the symptom factors were significantly related to memory performance over and above the variable of time since injury, such that longer time since injury was related to worse memory performance.

CONCLUSION

Comparable to work examining symptom predictors of cognitive outcomes in acutely concussed samples, headache predicted worse attention/executive functioning performance. Additionally, we found that the longer athletes had been symptomatic since injury, the "worse" their memory functioning. Understanding how headache and the length of time an individual is symptomatic are related to cognitive outcomes can help inform treatment and recommendations for athletes with prolonged symptom recovery.

Subtypes of Sport-Related Concussion: a Systematic Review and Meta-cluster Analysis

Objective

Current clinical guidelines provide a unitary approach to manage sport-related concussion (SRC), while heterogeneity in the presentation of symptoms suggests that subtypes of SRC may exist. We systematically reviewed the available evidence on SRC subtypes and associated clinical outcomes.

Data Sources

Ovid Medline, Embase, PsycINFO, and SPORTDiscus

Eligibility Criteria for Selecting Studies

Electronic databases were searched for studies: (i) identifying SRC symptom clusters using classification methodology; or (ii) associating symptom clusters to clinical outcome variables. A total of 6,146 unique studies were identified, of which 75 full texts were independently assessed by two authors for eligibility. A total of 22 articles were included for systematic review.

Data Extraction

Two independent authors performed data extraction and risk of bias analysis using the Cochrane Collaboration tool.

Data Synthesis

Six studies found evidence for existence of SRC symptom clusters. Combining the available literature through Multiple Correspondence Analysis (MCA) provided evidence for the existence of a migraine cluster, a cognitive–emotional cluster, a sleep–emotional cluster, a neurological cluster, and an undefined feelings cluster. Nineteen studies found meaningful associations between SRC symptom clusters and clinical outcomes. Clusters mapping to the migraine cluster were most frequently reported in the literature and were most strongly related to aspects of clinical outcome.

Conclusions

The available literature provides evidence for the existence of at least five subtypes in SRC symptomatology, with clear relevance to clinical outcome. Systematically embedding the differentiation of SRC subtypes into prognosis, clinical management, and intervention strategies may optimize the recovery from SRC.

Electronic supplementary material

The online version of this article (10.1007/s40279-020-01321-9) contains supplementary material, which is available to authorized users.

Bifactor Model of the Sport Concussion Assessment Tool Symptom Checklist: Replication and Invariance Across Time in the CARE Consortium Sample

BACKGROUND

Identifying separate dimensions of concussion symptoms may inform a precision medicine approach to treatment. It was previously reported that a bifactor model identified distinct acute postconcussion symptom dimensions.

PURPOSE

To replicate previous findings of a bifactor structure of concussion symptoms in the Concussion Assessment Research and Education (CARE) Consortium sample, examine measurement invariance from pre- to postinjury, and evaluate whether factors are associated with other clinical and biomarker measures.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 2.

METHODS

Collegiate athletes were prospectively evaluated using the Sport Concussion Assessment Tool-3 (SCAT-3) during preseason (N = 31,557); 2789 were followed at <6 hours and 24 to 48 hours after concussion. Item-level SCAT-3 ratings were analyzed using exploratory and confirmatory factor analyses. Bifactor and higher-order models were compared for their fit and interpretability. Measurement invariance tested the stability of the identified factor structure across time. The association between factors and criterion measures (clinical and blood-based markers of concussion severity, symptom duration) was evaluated.

RESULTS

The optimal structure for each time point was a 7-factor bifactor model: a General factor, on which all items loaded, and 6 specific factors-Vestibulo-ocular, Headache, Sensory, Fatigue, Cognitive, and Emotional. The model manifested strict invariance across the 2 postinjury time points but only configural invariance from baseline to postinjury. From <6 to 24-48 hours, some dimensions increased in severity (Sensory, Fatigue, Emotional), while others decreased (General, Headache, Vestibulo-ocular). The factors correlated with differing clinical and biomarker criterion measures and showed differing patterns of association with symptom duration at different time points.

CONCLUSION

Bifactor modeling supported the predominant unidimensionality of concussion symptoms while revealing multidimensional properties, including a large dominant General factor and 6 independent factors: Headache, Vestibulo-ocular, Sensory, Cognitive, Fatigue, and Emotional. Unlike the widely used SCAT-3 symptom severity score, which declines gradually after injury, the bifactor model revealed separable symptom dimensions that have distinct trajectories in the acute postinjury period and different patterns of association with other markers of injury severity and outcome.

CLINICAL RELEVANCE

The SCAT-3 total score remains a valuable, robust index of overall concussion symptom severity, and the specific factors identified may inform management strategies. Because some symptom dimensions continue to worsen in the first 24 to 48 hours after injury (ie, Sensory, Fatigue, Emotional), routine follow-up in this time frame may be valuable to ensure that symptoms are managed effectively.

Determining Outcome in Children and Adolescents After Concussion: Viewing Things More Holistically

Pediatric and adolescent concussion is an increasingly high-profile public health issue, but it is also a highly heterogeneous phenomenon. Many factors interact dynamically to influence the recovery trajectory of adolescents and children. Diagnostic assessment must include domains other than self-reported symptoms, yet many prognostic models of outcome focus solely on the presence or absence of postconcussion symptoms to determine recovery. Function after concussion (recovery or persistence of problems) is the result of an interaction between biological, psychological, and social factors. Despite biopsychosocial models of assessment being advocated in rehabilitation for the last 20 years, they are still not routinely implemented in the evaluation of concussions, along the recovery trajectory, in children and adolescents. The International Classification of Functioning, Disability and Health is a framework anchored in a biopsychosocial perspective that can guide clinicians and researchers to include multiple perspectives in their assessments or research designs. By focusing on the patient as a person, researchers and clinicians can provide a more holistic approach that has the potential to contribute to a more successful and sustainable pediatric and adolescent concussion care model. J Orthop Sports Phys Ther 2019;49(11):855-863. Epub 9 Oct 2019. doi:10.2519/jospt.2019.8918.