Factors Associated With Delayed Concussion Reporting by United States Service Academy Cadets

Sex Differences Across Concussion Characteristics in US Service Academy Cadets: A CARE Consortium Study

OBJECTIVE

To describe sex differences in concussion characteristics in US Service Academy cadets.

DESIGN

Descriptive epidemiology study.

SETTING

Four US service academies.

PARTICIPANTS

2209 cadets (n = 867 females, n = 1342 males).

INDEPENDENT VARIABLE

Sex.

OUTCOME MEASURES

Injury proportion ratios (IPR) compared the proportion of injuries by sex (females referent) for injury situation, certainty of diagnosis, prolonged recovery, recurrent injuries, mental status alterations, loss of consciousness (LOC), posttraumatic amnesia (PTA), retrograde amnesia (RGA), motor impairments, delayed symptom presentation, and immediate reporting.

MAIN RESULTS

Concussions from varsity/intercollegiate sports [IPR of 1.73, 95% confidence interval (CI) 1.43-2.10] and intramurals (IPR of 1.53, 95% CI 1.02-2.32) accounted for a larger proportion in males, whereas concussions outside of sport and military activities accounted for a smaller proportion among males (IPR of 0.70, 95% CI 0.58-0.85). The proportion of concussions with prolonged recovery was lower among males (IPR of 0.69, 95% CI 0.60-0.78), while concussions with altered mental status (IPR of 1.23, 95% CI 1.09-1.38), LOC (IPR of 1.67, 95% CI 1.17-2.37), PTA (IPR of 1.94, 95% CI 1.43-2.62), and RGA (IPR of 2.14, 95% CI 1.38-3.31) accounted for a larger proportion among males. A larger proportion of concussions that were immediately reported was observed in males (IPR of 1.15, 95% CI 1.00-2.31). Proportions of other characteristics (e.g., recurrent injuries) were not different between sexes.

CONCLUSIONS

A higher proportion of concussions occurred outside of sport and military training for female cadets, who also displayed proportionally longer recovery times than males, despite males demonstrating a higher proportion of LOC, PTA, and RGA. Possible factors may include different mechanisms of injury outside of sport and military training, different biopsychosocial states associated with sex or injury context, and delayed injury reporting when outside of an observed environment, possibly secondary to perceived stigma about reporting injuries.

Optimizing Concussion Care Seeking: Connecting Care-Seeking Behaviors and Neurophysiological States Through Blood Biomarkers

BACKGROUND

Timely and appropriate medical care after concussion presents a difficult public health problem. Concussion identification and treatment rely heavily on self-report, but more than half of concussions go unreported or are reported after a delay. If incomplete self-report increases exposure to harm, blood biomarkers may objectively indicate this neurobiological dysfunction.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare postconcussion biomarker levels between individuals with different previous concussion diagnosis statuses and care-seeking statuses. It was hypothesized that individuals with undiagnosed concussions and poorer care seeking would show altered biomarker profiles.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Blood samples were collected from 287 military academy cadets and collegiate athletes diagnosed with concussion in the Advanced Research Core of the Concussion Assessment, Research and Education Consortium. The authors extracted each participant's self-reported previous concussion diagnosis status (no history, all diagnosed, ≥1 undiagnosed) and whether they had delayed or immediate symptom onset, symptom reporting, and removal from activity after the incident concussion. The authors compared the following blood biomarkers associated with neural injury between previous concussion diagnosis status groups and care-seeking groups: glial fibrillary acidic protein, ubiquitin c-terminal hydrolase-L1 (UCH-L1), neurofilament light chain (NF-L), and tau protein, captured at baseline, 24 to 48 hours, asymptomatic, and 7 days after unrestricted return to activity using tests of parallel profiles.

RESULTS

The undiagnosed previous concussion group (n = 21) had higher levels of NF-L at 24- to 48-hour and asymptomatic time points relative to all diagnosed (n = 72) or no previous concussion (n = 194) groups. For those with delayed removal from activity (n = 127), UCH-L1 was lower at 7 days after return to activity than that for athletes immediately removed from activity (n = 131). No other biomarker differences were observed.

CONCLUSION

Individuals with previous undiagnosed concussions or delayed removal from activity showed some different biomarker levels after concussion and after clinical recovery, despite a lack of baseline differences. This may indicate that poorer care seeking can create neurobiological differences in the concussed brain.

Association of Use of a Mobile Tackling Dummy During College Football Practice With Reduced Sport-Related Concussion: Results of a Pilot Investigation

Background

Considering the multifaceted consequences of improperly managed sport-related concussions (SRCs) in American football, identifying efficacious prevention measures for enhancing player safety is crucial.

Purpose

To investigate the association of primary prevention measures (no-tackle practices and using a mobile tackling dummy in practice) with the frequency of SRCs within college football programs in the United States.

Study Design

Descriptive epidemiology study.

Methods

In this pilot study, we analyzed the frequency of new SRCs recorded during various settings (total, in preseason, in season, in practice, and game) across 14 seasons (2007-2019 and 2021) for Dartmouth College and across 7 seasons (2013-2019) for the 7 other teams in the Ivy League men's athletic football conference. Trends between seasons and the number of SRCs sustained were examined using correlations and basic descriptive statistics. We also examined SRC frequency in relation to primary prevention measures (no-tackle practices, use of mobile tackling dummies during practice) in the Dartmouth College football program, and we compared SRCs with regard to the no-tackle practice policy in the other Ivy League teams.

Results

There was a statistically significant reduction in the number of SRCs over the seasons studied, with the strongest finding observed for Dartmouth College in-game SRCs (r = -0.52; P = .029). Relatedly, the strongest between-season effect was seen for the Dartmouth College practice policy on in-game SRCs (η2 = 0.510; P = .01). The use of mobile tackling dummies was found to be independently associated (adjusting for no-tackle practice) with a lower number total (β = -0.53; P = .049), in-season (β = -0.63; P = .023), and in-game (β = -0.79; P = .003) SRCs. While seasons with the no-tackle practice were not meaningfully associated with SRCs for Dartmouth College, stronger trends were observed in the other Ivy League teams, such that seasons with this policy were associated with lower SRC prevalence.

Conclusion

Our data indicate that the use of the mobile tackling dummy in practice was related to the reduced number of SRCs sustained at multiple settings during the football season. To a lesser extent, the no-tackle practice policy was also associated with a reduced number of SRCs.

Early vs. delayed evaluation and persisting concussion symptoms during recovery in adults

Objective: Persisting concussion symptoms may adversely affect return to work and functioning in daily activities. This study compared adults who were initially evaluated < 30 days versus those evaluated ≥ 30 days following a concussion at a specialty concussion clinic to determine if delayed initial evaluation is associated with persisting symptoms during recovery. Method: Participants (N = 205) 18 years of age and older who sustained a concussion and presented to a North Texas Concussion Registry (ConTex) clinic were evaluated at two time points: initial clinical visit and three-month follow-up. Participants provided medical history, injury related information, and completed the Sport Concussion Assessment Tool-5 Symptom Evaluation, Generalized Anxiety Disorder 7-item scale (GAD-7), and Patient Health Questionnaire (PHQ-8). Participants were divided into two groups: early and delayed evaluation (±30 days post injury). Results: Number and severity of concussion symptoms were similar between both groups at their initial clinical visit. However, linear regression models showed that a delayed clinical evaluation was associated with a greater number and severity of concussion symptoms along with greater aggravation of symptoms from physical and cognitive activity at three-month follow-up. Conclusions: Individuals who sought care at specialty concussion clinics regardless of previous care 30 or more days following their injury reported more serious persisting concussion symptoms at three month follow-up than those who sought care sooner. Education to improve adults' recognition of concussions when they occur and obtaining earlier clinical evaluation may represent important opportunities in promoting better recovery and reducing persisting concussion symptoms.

Initial Mild Traumatic Brain Injury Characteristics and Recovery Patterns Among Females Across the United States Military Service Academies: A Report from the NCAA-DoD CARE Consortium

Mild traumatic brain injury (mTBI) has been described in the United States (US) military service academy cadet population, but female-specific characteristics and recovery outcomes are poorly characterized despite sex being a confounder. Our objective was to describe female cadets' initial characteristics, assessment performance, and return-to-activity outcomes post-mTBI. Female cadets (n = 472) from the four US military service academies who experienced a mTBI completed standardized mTBI assessments from pre-injury to acute initial injury and unrestricted return-to-duty (uRTD). Initial injury presentation characteristics (e.g., delayed symptoms, retrograde amnesia) and return-to-activity outcomes [i.e., return-to-learn, initiate return-to-duty protocol (iRTD), uRTD] were documented. Descriptive statistics summarized female cadets' injury characteristics, return-to-activity outcomes, and post-mTBI assessment performance change categorization (worsened, unchanged, improved) relative to pre-injury baseline using established change score confidence rank criteria for each assessment score. The median (interquartile range) days to return-to-learn (n = 157) was 7.0 (3.0-14.0), to iRTD (n = 412) was 14.7 (8.6-25.8), and to uRTD (n = 431) was 26.0 (17.7-41.8). The majority experienced worse SCAT total symptom severity (77.8%) and ImPACT reaction time (97.0%) acutely < 24-h versus baseline, but unchanged BESS total errors (75.2%), SAC total score (72%), BSI-18 total score (69.6%), and ImPACT verbal memory (62.3%), visual memory (58.4%), and visual motor speed (52.5%). We observed similar return-to-activity times in the present female cadet cohort relative to the existing female-specific literature. Confidence ranks categorizing post-mTBI performance were heterogenous and indicate multimodal assessments are necessary. Our findings provide clinically relevant insights to female cadets experiencing mTBI across the US service academies for stakeholders providing healthcare.

Primary and Secondary Risk Factors Associated With Concussion Symptom Clusters in Collegiate Athletes: Results From the NCAA-DoD Grand Alliance CARE Consortium

Background

There is a broad and diverse range of symptoms after a concussion, from irritability to nausea. This heterogeneity of symptoms is a challenge for clinicians managing the different presentations among injuries. Prior research has investigated the structure of postconcussive symptoms to determine if they can be grouped into clusters of related symptoms.

Purpose/Hypothesis

The purpose of this study was to identify symptom clusters during the acute phase after a sports-related concussion using exploratory factor analysis and to understand the relationship between risk factors for postconcussion symptoms (ie, demographics, injury characteristics, mental health, and sleep qualities) and different symptom clusters. We hypothesized that certain factors would be predictive of specific symptom clusters.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Collegiate athletes (N = 1104) from the Concussion, Assessment, Research, and Education (CARE) Consortium completed the Sport Concussion Assessment Tool-Third Edition symptom assessment tool 24 to 48 hours after concussion. Exploratory factor analysis was conducted on the symptom evaluation to determine symptom clusters 24 to 48 hours after concussion. Regression analysis was used to examine the effects of pre- and postinjury characteristics.

Results

Exploratory factor analysis revealed a 4-cluster structure for acute postconcussive symptoms that explained 62% of the variance in symptom reporting: vestibular-cognitive, migrainous, cognitive fatigue, and affective. Delayed reporting, less sleep before assessment, female sex, and being hurt outside of competition (during practice/training) was correlated with increased symptoms for 4 symptom clusters. Depression predicted higher vestibular-cognitive and affective symptoms. Amnesia was correlated with higher vestibular-cognitive and migrainous symptoms, whereas migraine history was associated with more migrainous and affective symptoms.

Conclusion

Symptoms can be grouped into 1 of 4 distinct clusters. Certain variables were associated with increased symptoms across multiple clusters and may be indicative of greater injury severity. Other factors (ie, migraine history, depression, amnesia) were associated with a more specific symptom presentation and may be mechanistically related to concussion outcomes and biological markers.

Trends in concussion mechanism of injury during the COVID-19 pandemic

OBJECTIVE

The primary objective was to determine the effect of the COVID-19 pandemic on volume, demographics, and mechanisms of injury (MOI) for patients seen at an urban multidisciplinary concussion center. During the first phase of the pandemic in the United States, stay-at-home orders led to decreased group activities and required cancellation of outpatient appointments or initiation of telemedicine visits.

METHODS

This study was a retrospective chart review of 3500 patient electronic medical records (EMR). Patients aged 1-99 years were eligible if they had been seen at New York University Langone Health Concussion Center during March 1-December 31, 2019 (control/pre-pandemic period) or during the same period in 2020 (pandemic period). Injury date, appointment date, age, sex, and MOI were captured; statistical analyses were performed using Stata17 (StataCorp, College Station, TX).

RESULTS

There were 48% fewer visits during the COVID-19 pandemic period compared to the 2019 control period. There was a decreased proportion of pediatric patients (15% control, 6% pandemic; p = 0.007, chi-square test). Fewer concussions were related to team sports (21% control, 5% pandemic; p < 0.001), and a greater proportion were caused by bicycle accidents (4% control, 8% pandemic; p = 0.037) and assault/domestic violence (3% control, 9% pandemic; p < 0.001).

CONCLUSION

The relative proportions of concussion MOI, age distributions, and visit volumes were significantly associated with pre-pandemic vs. pandemic periods, suggesting that COVID-19 changed concussion epidemiology during the pandemic period. This study demonstrates how epidemiologic data may inform future resource allocation during public health emergencies.

Optimizing Concussion Care Seeking: A Longitudinal Analysis of Recovery

BACKGROUND

Approximately half of concussions go undisclosed and therefore undiagnosed. Among diagnosed concussions, 51% to 64% receive delayed medical care. Understanding the influence of undiagnosed concussions and delayed medical care would inform medical and education practices.

PURPOSE

To compare postconcussion longitudinal clinical outcomes among (1) individuals with no concussion history, all previous concussions diagnosed, and ≥1 previous concussion undiagnosed, as well as (2) those who have delayed versus immediate symptom onset, symptom reporting, and removal from activity after concussion.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Participants included 2758 military academy cadets and intercollegiate athletes diagnosed with concussion in the CARE Consortium. We determined (1) each participant's previous concussion diagnosis status self-reported at baseline (no history, all diagnosed, ≥1 undiagnosed) and (2) whether the participant had delayed or immediate symptom onset, symptom reporting, and removal from activity. We compared symptom severities, cognition, balance, and recovery duration at baseline, 24 to 48 hours, date of asymptomatic status, and date of unrestricted return to activity using tests of parallel profiles.

RESULTS

The ≥1 undiagnosed concussion group had higher baseline symptom burdens (P < .001) than the other 2 groups and poorer baseline verbal memory performance (P = .001) than the all diagnosed group; however, they became asymptomatic and returned to activity sooner than those with no history. Cadets/athletes who delayed symptom reporting had higher symptom burdens 24 to 48 hours after injury (mean ± SE; delayed, 28.8 ± 0.8; immediate, 20.6 ± 0.7), took a median difference of 2 days longer to become asymptomatic, and took 3 days longer to return to activity than those who had immediate symptom reporting. For every 30 minutes of continued participation after injury, days to asymptomatic status increased 8.1% (95% CI, 0.3%-16.4%).

CONCLUSION

Clinicians should expect that cadets/athletes who delay reporting concussion symptoms will have acutely higher symptom burdens and take 2 days longer to become asymptomatic. Educational messaging should emphasize the clinical benefits of seeking immediate care for concussion-like symptoms.

Heart Rate Variability as a Reliable Biomarker Following Concussion: A Critically Appraised Topic

CLINICAL SCENARIO

Recent systematic reviews show conflicting information regarding the effect of concussion on cardiac autonomic function. Controlled aerobic exercise is the most popular intervention for those recovering from a concussion. There is a gap in the literature supporting the utility of objective metrics during exertional return to play protocols and rehabilitation.

CLINICAL QUESTION

Can heart rate variability (HRV) during physical exertion be a reliable biomarker over time for those who suffered a sport-related concussion?

SUMMARY OF KEY FINDINGS

A literature search produced 3 studies relevant to the clinical question. One, a prospective-matched control group cohort study, reported disturbances in HRV during physical exertion in those with a history of concussion, and identified persistent HRV dysfunction after resolution of subjective complaints, return to play, and with multiple concussive events. Second, a cross-sectional cohort study found an HRV difference in those with and without a history of concussion and in HRV related to age and sex. Finally, the prospective longitudinal case-control cohort study did not find sex or age differences in HRV and concluded that, although postconcussion HRV improved as time passed, resting HRV was not as clinically meaningful as HRV during exertional activities.

CLINICAL BOTTOM LINE

There is emerging evidence to support the use of HRV as an observable biomarker, over time, of autonomic function during physical exertion following a sport-related concussion. However, the meaningfulness of HRV data is not fully understood and the utility seems individualized to the level of athlete, age, and sex and, therefore, cannot be generalizable. In order to be more clinically meaningful and to assist with current clinical decision making regarding RTP, a preinjury baseline assessment would be beneficial as an individualized reference for baseline comparison.

STRENGTH OF RECOMMENDATION

Although HRV is not fully understood, currently, there is grade B evidence to support the use of individualized baseline exertional HRV data as comparative objective metric to assess the autonomic nervous system function, over time, following a concussive event.

Participating in Two Video Concussion Education Programs Sequentially Improves Concussion-Reporting Intention

Undiagnosed concussions increase the risk of additional concussion and persistent symptoms from concussion. Because there are no reliable objective markers of concussion, self-reporting of subjective and non-visible symptoms are critical to ensuring proper concussion management. For this reason, educational interventions target concussion reporting, but the majority of studies have examined the efficacy of single educational interventions or compared interventions to one another. This randomized crossover study sought to identify whether there was benefit to administering multiple concussion education programs in tandem, back to back. The study randomized 313 male high school football players to first receive CrashCourse concussion education (CC) or Centers for Disease Control and Prevention video concussion education (CDC) followed by crossover with the other education. Athlete concussion-reporting intention, attitudes, subjective norms, perceived behavioral control, and enjoyment of education were assessed at baseline and after each intervention. There were statistically significant improvements across all measures, both after single intervention and crossover (all p < 0.001). Secondary analyses examining differences between education found that athletes reported higher enjoyment of concussion education immediately after participating in CC, as compared to CDC (p < 0.001). These findings demonstrate an additive benefit to implementing CC and CDC education in tandem, without decrement in enjoyment of concussion education after experiencing dual educations; in fact, enjoyment of concussion education improved after receiving education programs back to back. These educational programs appear to complement one another, and the results support the use of multi-modal concussion education to differentially target and maximize concussion reporting.

Leadership Lessons in Concussion Management for Team Physicians

Over the last decade, with emphasis on concussion awareness and potential long-term deficits, concussions have become a public health concern. Although common, concussions are complex in nature and often require a collaborative treatment approach across multiple disciplines. In an athletic setting, the Team Physician plays a critical leadership role in the organization, management, and provision of care for concussed athletes. However, leadership strategies for the provision of concussion care utilized by the Team Physician have not been adequately described. This manuscript intends to describe advanced planning for concussion management and highlight best practices for the provision of care for the concussed athlete, to assist the Team Physician in coordinating optimal care. Specific emphasis will be placed on outlining a concussion management protocol aligned with evidence-based best practices.

The Influence of Timing of Reporting and Clinic Presentation on Concussion Recovery Outcomes: A Systematic Review and Meta-Analysis

BACKGROUND

Identifying risk factors for prolonged recovery following concussion can assist clinicians with appropriate management strategies. It is thought that athletes who continue to participate following a hit to the head or body may take longer to recover following a concussion diagnosis.

OBJECTIVE

To systematically review the body of literature regarding the effect of delayed reporting and delayed presentation to medical providers on concussion recovery times.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

PubMed, Ovid Medline, SPORTDiscus, Cochrane Central Register of Controlled Trials and hand searches of reference lists. All the searches were performed in April 2020.

ELIGIBILITY CRITERIA FOR SELECTED STUDIES

Studies included an investigation of immediate versus delayed reporting or early versus late presentation following a concussion, were published in the past ten years, and were level 4 evidence or higher.

RESULTS

12 studies were included. Patients who continued play or delayed reporting their concussion had significantly longer recovery times (standardized mean difference = 0.36 days (95%CI 0.066, 0.662) than those who immediately reported or were removed from play (p = 0.017). Expressed in raw scores, those who immediately reported recovered in 5.4 days (95% CI - 10.14, - 0.75) fewer than delayed reporters. Comparable results were found for post-concussion symptom scores (p = 0.034) with immediate reporters demonstrating lower symptom severity scores. Our qualitative synthesis found patients who presented earlier to a concussion specialist tended to recover faster than those who presented later.

CONCLUSIONS

Patients who delayed reporting or continued play had longer recovery times compared to their immediately-reporting peers. Providers should ask concussion patients approximately how long they waited to report their injury, and also focus educational efforts on encouraging immediate reporting of concussion.

Evaluating the Effect of Concussion Education Programs on Intent to Report Concussion in High School Football

CONTEXT

Concussion underreporting leads to delays in diagnosis and treatment, prolonging recovery time. Athletes' self-report of concussion symptoms therefore reduces risk.

OBJECTIVE

Evaluate the efficacy of three concussion education programs in improving concussion-reporting intention.

DESIGN

Randomized controlled clinical trial with assessment immediately and one-month after education.

SETTING

Three high schools in California.

PATIENTS OR OTHER PARTICIPANTS

118 male football players were randomly assigned to receive concussion education via: CrashCourse (CC), Centers for Disease Control (CDC) video educational materials (Vi), or CDC written educational materials (Wr).

MAIN OUTCOME MEASURES

Concussion-reporting intention was assessed at baseline, immediately after education, and at one-month follow-up. Secondary outcomes included concussion knowledge, attitudes, perceived reporting norms, and perceived behavioral control.

RESULTS

Athletes across all educational formats had significant improvement in concussion-reporting intention immediately following education and at one-month follow-up (mean improvement 6.8% and 11.4%, respectively; p<0.001). Similar findings were observed across all education formats in secondary analyses examining knowledge, attitudes, and perceived behavioral control. However, there were significant differences by education and time (p=0.03). On post-hoc analysis, athletes who received CC had increased concussion-reporting intention immediately and at one-month (baseline=4.7, immediate=6.1, one-month=6.0; p=0.007 compared to significant increases only at one-month for CDC-Vi (baseline=4.3, immediate=5.2, one-month=5.8; p=0.001), and no significant improvement for CDC-Wr (p=0.10). Secondary analyses indicated significant differences between CC and both CDC interventions, in concussion knowledge and attitudes, immediately after education and at one-month. There were no significant differences in perceived behavioral control between-interventions or in perceived concussion-reporting norms across or between interventions.

CONCLUSION

All athletes exhibited improved intent to report concussions, increased concussion knowledge, better concussion attitudes, and more perceived behavioral control, both immediately after education and at one-month follow-up. However, athletes randomized to CC reported greater intent to report concussion, more knowledge, and improved concussion-reporting attitudes, when compared to CDC-Vi and CDC-Wr.

TRIAL REGISTRY

ClinicalTrials.gov trial ID number is XXX.

Progress and Future Directions of the NCAA-DoD Concussion Assessment, Research, and Education (CARE) Consortium and Mind Matters Challenge at the US Service Academies

Despite the significant impact that concussion has on military service members, significant gaps remain in our understanding of the optimal diagnostic, management, and return to activity/duty criteria to mitigate the consequences of concussion. In response to these significant knowledge gaps, the US Department of Defense (DoD) and the National Collegiate Athletic Association (NCAA) partnered to form the NCAA-DoD Grand Alliance in 2014. The NCAA-DoD CARE Consortium was established with the aim of creating a national multisite research network to study the clinical and neurobiological natural history of concussion in NCAA athletes and military Service Academy cadets and midshipmen. In addition to the data collected for the larger CARE Consortium effort, the service academies have pursued military-specific lines of research relevant to operational and medical readiness associated with concussion. The purpose of this article is to describe the structure of the NCAA-DoD Grand Alliance efforts at the service academies, as well as discuss military-specific research objectives and provide an overview of progress to date. A secondary objective is to discuss the challenges associated with conducting large-scale studies in the Service Academy environment and highlight future directions for concussion research endeavors across the CARE Service Academy sites.