Acute Postconcussion Research Articles

B - 48 Gender-Based Network Comparisons of the Post-Concussion Symptom Scale at Acute Post-Concussion

Abstract Objective Prior literature suggests there may be gender-based differences in Post-Concussion Symptom Scale (PCSS) scores, with girls reporting more symptoms than boys at pre- and post-concussion. PCSS network analysis comparisons on gender have been conducted at pre-concussion but not post-concussion, which can determine whether gender-based differences in symptom relationships exist post-concussion. We conducted network comparisons between boys and girls from a sample of high school athletes at acute post-concussion to analyze differences in symptom relationships. Method Separate network analyses were conducted on acute post-concussion PCSS scores (within 72 hours post-suspected concussion) for boys (n = 2032) and girls (n = 1246), with nodes representing PCSS items and edges representing partial correlations between them. Expected influence was calculated to determine node importance in each network. Network Comparison Tests were used to compare network structure, global connectivity, and expected influence. Results Both networks’ expected influences and edge weights were stable and interpretable. There were no significant differences in network structure, connectivity, and expected influence between the groups. Networks consisted of positive and negative edges; strongest edges connected symptoms within similar domains (e.g., light and noise sensitivity). Conclusions Current results suggest that prior reports of gender-based differences in PCSS scores following concussion do not appear to be accounted for by differences in how PCSS items interact and influence each other. Differences may reflect actual differences in type and severity of post-concussion symptoms experienced by boys and girls or reflect differences in symptom reporting based on cultural influences. Future research could examine cultural or societal factors that influence gender-based differences in symptom reporting.

64 Comparison of Post-Concussion Symptom Network Structure at Baseline and Post-Concussion

Objective:Recent conceptualizations of concussion symptoms have begun to shift from a latent perspective (which suggests a common cause; i.e., head injury), to a network perspective (where symptoms influence and interact with each other throughout injury and recovery). Recent research has examined the network structure of the Post-Concussion Symptom Scale (PCSS) cross-sectionally at pre-and post-concussion, with the most important symptoms including dizziness, sadness, and feeling more emotional. However, within-subject comparisons between network structures at pre-and post-concussion have yet to be made. These analyses can provide invaluable information on whether concussion alters symptom interactions. This study examined within-athlete changes in PCSS network connectivity and centrality (the importance of different symptoms within the networks) from baseline to post-concussion.Participants and Methods:Participants were selected from a larger longitudinal database of high school athletes who completed the PCSS in English as part of their standard athletic training protocol (N=1,561). The PCSS is a 22-item self-report measure of common concussion symptoms (i.e., headache, vomiting, dizziness, etc.) in which individuals rate symptom severity on a 7-point Likert scale. Participants were excluded if they endorsed history of brain surgery, neurodevelopmental disorder, or treatment history for epilepsy, migraines, psychiatric disorders, or alcohol/substance use. Network analysis was conducted on PCSS ratings from a baseline and acute post-concussion (within 72-hours post-injury) assessment. In each network, the nodes represented individual symptoms, and the edges connecting them their partial correlations. Estimations of the regularized partial correlation networks were completed using the Gaussian graphical model, and the GLASSO algorithm was used for regularization. Each symptom’s expected influence (the sum of its partial correlations with other symptoms) was calculated to identify the most central symptoms in each network. Recommended techniques from Epskamp et al. (2018) were completed for assessing the accuracy of the estimated symptom importance and relationships. Network Comparison Tests were conducted to observe changes in network connectivity, structure, and node influence.Results:Both baseline and acute post-concussion networks contained negative and positive relationships. The expected influence of symptoms was stable in both networks, with difficulty concentrating having the greatest expected influence in both. The strongest edges in the networks were between symptoms within similar domains of functioning (e.g., sleeping less was associated with trouble falling asleep). Network connectivity was not significantly different between networks (S=0.43), suggesting the overall degree to which symptoms are related was not different at acute post-concussion. Network structure significantly differed at acute post-concussion (M=0.305), suggesting specific relationships in the acute post-concussion network were different than they were at baseline. In the acute post concussion network, vomiting was less central and sensitivity to noise and mentally foggy more central.Conclusions:PCSS network structure at acute post-concussion is altered, suggesting concussion may disrupt symptom networks and certain symptoms’ associations with the experience of others after sustaining a concussive injury. Future research should compare PCSS networks later in recovery to examine if similar structural changes remain or return to baseline structure, with the potential that observing PCSS network structure changes post-concussion could inform symptom resolution trajectories.

Acute Post-Concussion Assessment Using Gamified Neurocognitive Performance In Collegiate Athletes

Acute Post-Concussion Assessment Using Gamified Neurocognitive Performance In Collegiate Athletes

Single-Leg Hop Stabilization Throughout Concussion Recovery: A Preliminary Biomechanical Assessment.

Aberrant movement patterns among individuals with concussion history have been reported during sport-related movement. However, the acute postconcussion kinematic and kinetic biomechanical movement patterns during a rapid acceleration-deceleration task have not been profiled and leaves their progressive trajectory unknown. Our study aimed to examine single-leg hop stabilization kinematics and kinetics between concussed and healthy-matched controls acutely (≤7d) and when asymptomatic (≤72h of symptom resolution). Prospective, cohort laboratory study. Ten concussed (60% male; 19.2 [0.9]y; 178.7 [14.0]cm; 71.3 [18.0]kg) and 10 matched controls (60% male; 19.5 [1.2]y; 176.1 [12.6]cm; 71.0 [17.0]kg) completed the single-leg hop stabilization task under single and dual task (subtracting by 6's or 7's) at both time points. Participants stood on a 30-cm tall box set 50% of their height behind force plates while in an athletic stance. A synchronized light was illuminated randomly, queuing participants to initiate the movement as rapidly as possible. Participants then jumped forward, landed on their nondominant leg, and were instructed to reach and maintain stabilization as fast as possible upon ground contact. We used 2 (group) × 2 (time) mixed-model analyses of variance to compare single-leg hop stabilization outcomes separately during single and dual task. We observed a significant main group effect for single-task ankle plantarflexion moment, with greater normalized torque (mean difference = 0.03N·m/body weight; P = .048, g = 1.18) for concussed individuals across time points. A significant interaction effect for single-task reaction time indicated that concussed individuals had slower performance acutely relative to asymptomatic (mean difference = 0.09s; P = .015, g = 0.64), while control group performance was stable. No other main or interaction effects for single-leg hop stabilization task metrics were present during single and dual task (P ≥ .051). Greater ankle plantarflexion torque coupled with slower reaction time may indicate stiff, conservative single-leg hop stabilization performance acutely following concussion. Our findings shed preliminary light on the recovery trajectories of biomechanical alterations following concussion and provide specific kinematic and kinetic focal points for future research.

Brain Connectivity, Acute Post-Concussion Symptoms, and Cognition in Adults With Concussion: A Quantitative Electroencephalography Study

Brain Connectivity, Acute Post-Concussion Symptoms, and Cognition in Adults With Concussion: A Quantitative Electroencephalography Study

Sport Concussion Assessment Tool Symptom Inventory: Healthy and Acute Postconcussion Symptom Factor Structures.

Previous researchers have examined factor structures for common concussion symptom inventories. However, they failed to discriminate between the acute (<72 hours) and subacute (3 days-3 months) periods after concussion. The Sport Concussion Assessment Tool (SCAT) is an acute assessment that, when compared with other concussion symptom inventories, includes or excludes symptoms that may result in different symptom factors. The primary purpose was to investigate the symptom factor structure of the 22-item SCAT symptom inventory in healthy, uninjured and acutely concussed high school and collegiate athletes. The secondary purpose was to document the frequency of the unique SCAT symptom inventory items. Case series. High school and college. A total of 1334 healthy, uninjured and 200 acutely concussed high school and collegiate athletes. Healthy, uninjured participants completed the SCAT symptom inventory at a single assessment. Participants in the acutely concussed sample completed the SCAT symptom inventory within 72 hours after concussion. Two separate exploratory factor analyses (EFAs) using a principal component analysis and varimax extraction method were conducted. A 3-factor solution accounted for 48.1% of the total variance for the healthy, uninjured sample: cognitive-fatigue (eg, feeling "in a fog" and "don't feel right"), migraine (eg, neck pain and headache), and affective (eg, more emotional and sadness) symptom factors. A 3-factor solution accounted for 55.0% of the variance for the acutely concussed sample: migraine-fatigue (eg, headache and "pressure in the head"), affective (eg, sadness and more emotional), and cognitive-ocular (eg, difficulty remembering and balance problems) symptom factors. The inclusion of unique SCAT symptom inventory items did not alter the symptom factor structure for the healthy, uninjured sample. For the acutely concussed sample, all but 1 unique SCAT symptom inventory item (neck pain) loaded onto a factor.

Sport Concussion Assessment Tool Symptom Inventory: Healthy and Acute Postconcussion Symptom Factor Structures.

Previous researchers have examined factor structures for common concussion symptom inventories. However, they failed to discriminate between the acute (<72 hours) and subacute (3 days-3 months) periods after concussion. The Sport Concussion Assessment Tool (SCAT) is an acute assessment that, when compared with other concussion symptom inventories, includes or excludes symptoms that may result in different symptom factors. The primary purpose was to investigate the symptom factor structure of the 22-item SCAT symptom inventory in healthy, uninjured and acutely concussed high school and collegiate athletes. The secondary purpose was to document the frequency of the unique SCAT symptom inventory items. Case series. High school and college. A total of 1334 healthy, uninjured and 200 acutely concussed high school and collegiate athletes. Healthy, uninjured participants completed the SCAT symptom inventory at a single assessment. Participants in the acutely concussed sample completed the SCAT symptom inventory within 72 hours after concussion. Two separate exploratory factor analyses (EFAs) using a principal component analysis and varimax extraction method were conducted. A 3-factor solution accounted for 48.1% of the total variance for the healthy, uninjured sample: cognitive fatigue (eg, feeling "in a fog" and "don't feel right"), migraine (eg, neck pain and headache), and affective (eg, more emotional and sadness) symptom factors. A 3-factor solution accounted for 55.0% of the variance for the acutely concussed sample: migraine fatigue (eg, headache and "pressure in the head"), affective (eg, sadness and more emotional), and cognitive ocular (eg, difficulty remembering and balance problems) symptom factors. The inclusion of unique SCAT symptom inventory items did not alter the symptom factor structure for the healthy, uninjured sample. For the acute concussed sample, all but 1 unique SCAT symptom inventory item (neck pain) loaded onto a factor.

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.

Cannabis, alcohol and cigarette use during the acute post-concussion period

ABSTRACTObjective: To document the prevalence of acute post-concussion cannabis, alcohol and cigarette use and their association with clinical recovery and symptom burden.Methods: A prospective cohort study was conducted. Concussions were physician-diagnosed and presented to the emergency department and concussion clinic within 7 days post-injury. Participants were assessed weekly and followed for a minimum 4 weeks. A survival analysis (using physician-determined recovery to both cognitive and physical activities) in addition to a weekly symptom score analysis was conducted.Results: A total of 307 acute concussions with a mean age of 33.7 years (SD, 13.0) were included. Acute post-concussion cannabis, alcohol and cigarette use were identified in 43 (14.0%), 125 (40.7%) and 61 (19.9%) individuals. Acute cannabis, alcohol and cigarette use were not associated with recovery to cognitive (p > .05) or physical activity (p > .05). Acute cigarette use was associated with a higher unadjusted symptom severity score at week1 (p = .003). Acute cannabis use was associated with lower symptom severity scores at week-3 (p = .061) and week-4 (p = .029).Conclusion: In conclusion, cannabis, alcohol and cigarette use were prevalent in the acute period post-concussion; however, were not observed to impact recovery within the first 4 weeks post-injury. Amongst unrecovered individuals, acute cannabis use was associated with lower symptom burden, while cigarette use was associated with greater initial symptom burden.

Clinical Utility of Oculomotor and Electrophysiological Measures in Identifying Concussion History.

To examine whether oculomotor and electrophysiological measures improve the clinical performance of the typical concussion protocol for classifying collegiate athletes with a history of concussion. Cross-sectional. University Athletic Medicine and Research Facility. Forty-five varsity collegiate athletes. Collegiate varsity athletes with or without a history of a diagnosed concussion. Multivariate receiver operating curve and area under the curve (AUC) analyses tested the clinical performance of the typical concussion protocol (symptoms, postural control, neuropsychological abilities). We examined differences in clinical performance between this protocol and after adding reflexive saccade and event-related potential (ERP) indices. Hypotheses were formed after data collection. Significant AUCs were demonstrated for the typical concussion protocol (model 1: AUC = 0.75, P = 0.007), after adding reflexive saccade eye excursion gain (model 2: AUC = 0.80, P = 0.001), and ERPs (model 3: AUC = 0.79, P = 0.002). The AUC for reflexive saccades and ERPs was significant (model 4: AUC = 0.70, P = 0.030). Model 2's increased clinical performance compared with model 1 was nonsignificant, χ(2) = 1.871, P = 0.171. All 4 models demonstrated adequate sensitivity and specificity for classifying athletes with a previous concussion. Adding reflexive saccades and ERPs did not significantly increase clinical performance of the typical concussion protocol. Future research should determine the clinical utility of saccades and ERPs for acute postconcussion assessments.

B-72Predicting Acute Post-Concussion Symptoms and Cognition from Pre-Injury Mental Health Treatment

B-72Predicting Acute Post-Concussion Symptoms and Cognition from Pre-Injury Mental Health Treatment

The Effectiveness of Acute Post-Concussion Cognitive and Physical Rest (S11.003)

The Effectiveness of Acute Post-Concussion Cognitive and Physical Rest (S11.003)

Neurogenic and Psychogenic Acute Postconcussion Symptoms Can Be Identified After Mild Traumatic Brain Injury

As provenance of postconcussion symptoms after mild traumatic brain injury (mTBI) is controversial, with similar rates found in other populations, we aimed to identify postconcussion symptoms specific to mTBI compared with controls. We also compared differences between complicated and uncomplicated mTBIs. Hospital emergency department. Adult individuals (34 individuals with complicated mTBI, 76 individuals with uncomplicated mTBI, and 47 orthopedic controls) who sought care in the emergency department and were consecutively recruited by post at 2 weeks postinjury. Rivermead Postconcussion Symptom Questionnaire. Preinjury factors were used as covariates. Compared with orthopedic controls, complicated mTBI group reported greater severity of headaches, dizziness, and nausea, as well as concentration difficulties, suggesting that these are neurogenic. Severity of other symptoms measured on the Rivermead Postconcussion Symptom Questionnaire was not significantly different between these groups, suggesting that these are psychogenic. Differences were evident between the 2 mTBI samples on the items of dizziness, nausea, fatigue, sleep disturbance, and concentration difficulties. Neurogenic and psychogenic postconcussion symptoms were identified at the acute-phase postinjury. Findings suggest that treating persons with mTBI as a homogenous sample is not prudent. This should inform prognostic models and follow-up support offered after leaving the emergency department.

Mild traumatic brain injury does not predict acute postconcussion syndrome

Background:The aetiology of postconcussion syndrome (PCS) following mild traumatic brain injury (mTBI) remains controversial. Identifying acute PCS (within the first 14 days after injury) may optimise initial recovery and rehabilitation,...