Refinement of saliva microRNA biomarkers for sports-related concussion

BACKGROUND

Recognizing sport-related concussion (SRC) is challenging and relies heavily on subjective symptom reports. An objective, biological marker could improve recognition and understanding of SRC. There is emerging evidence that salivary micro-ribonucleic acids (miRNAs) may serve as biomarkers of concussion; however, it remains unclear whether concussion-related miRNAs are impacted by exercise. We sought to determine whether 40 miRNAs previously implicated in concussion pathophysiology were affected by participation in a variety of contact and non-contact sports. Our goal was to refine a miRNA-based tool capable of identifying athletes with SRC without the confounding effects of exercise.

METHODS

This case-control study harmonized data from concussed and non-concussed athletes recruited across 10 sites. Levels of salivary miRNAs within 455 samples from 314 individuals were measured with RNA sequencing. Within-subjects testing was used to identify and exclude miRNAs that changed with either (a) a single episode of exercise (166 samples from 83 individuals) or (b) season-long participation in contact sports (212 samples from 106 individuals). The miRNAs that were not impacted by exercise were interrogated for SRC diagnostic utility using logistic regression (172 samples from 75 concussed and 97 non-concussed individuals).

RESULTS

Two miRNAs (miR-532-5p and miR-182-5p) decreased (adjusted p < 0.05) after a single episode of exercise, and 1 miRNA (miR-4510) increased only after contact sports participation. Twenty-three miRNAs changed at the end of a contact sports season. Two of these miRNAs (miR-26b-3p and miR-29c-3p) were associated (R > 0.50; adjusted p < 0.05) with the number of head impacts sustained in a single football practice. Among the 15 miRNAs not confounded by exercise or season-long contact sports participation, 11 demonstrated a significant difference (adjusted p < 0.05) between concussed and non-concussed participants, and 6 displayed moderate ability (area under curve > 0.70) to identify concussion. A single ratio (miR-27a-5p/miR-30a-3p) displayed the highest accuracy (AUC = 0.810, sensitivity = 82.4%, specificity = 73.3%) for differentiating concussed and non-concussed participants. Accuracy did not differ between participants with SRC and non-SRC (z = 0.5, p = 0.60).

CONCLUSION

Salivary miRNA levels may accurately identify SRC when not confounded by exercise. Refinement of this approach in a large cohort of athletes could eventually lead to a non-invasive, sideline adjunct for SRC assessment.

Parent-Child Communication regarding Sport-Related Concussion: An Application of the Theory of Planned Behavior

Extant research has discussed the importance of social climates surrounding sport-related concussion (SRC) reporting, especially the need to address parents/guardians' role in concussion management. This study explores parents/guardians' intentions toward SRC-related conversations with their children and their seeking of conversational resources via the Theory of Planned Behavior (TPB). Data collected from 292 parents/guardians of 1^st-12^th graders who play contact sports are examined via a structural equation model. The results indicate that parents/guardians' intention toward communicating with their child about SRC reporting was determined by their attitudes and subjective norms but that perceived behavioral control was not a significant predictor of intention. Furthermore, parents/guardians' intention toward having these conversations was predictive of whether they sought information to aid these conversations. This study answers calls to address parents/guardians' involvement in SRC management and provides preliminary information for persuading parents/guardians to have conversations with their children about SRC reporting.

Parent influence on concussion reporting in first-year collegiate athletes

OBJECTIVE

To assess the relationship between sport-parenting practices and concussion reporting intentions of collegiate athletes across two levels of competition.

PARTICIPANTS

Entering first-year student-athletes (varsity and club) at a mid-sized university in the Southeast region of the United States (n = 327).

METHODS

Written surveys were completed prior to the start of the 2015 academic year. Structural equation modeling was used to test a model predicting concussion-reporting intentions.

RESULTS

College athletes were more likely to intend to report a suspected concussion when they believed their parents wanted them to report (B=-0.88, SD = 0.94), and when they experienced less sport achievement pressure from their parents (B=-0.12, SD = 8.07).

CONCLUSIONS

Parents influence the concussion safety of entering collegiate athletes at both the varsity and club level. Lower pressure sport parenting prior to college entry may help foster safer concussion reporting behaviors and may be an appropriate target for future intervention development work.

Factors associated with parent and youth athlete concussion knowledge

INTRODUCTION

On-site health care providers are not routinely present at all youth sport events. Therefore, parents and youth athletes are often responsible for identifying and making appropriate immediate care decisions regarding concussions, which may be influenced by their injury health literacy. Previous studies have investigated the level of concussion knowledge of parents and athletes, but few have investigated factors associated with greater awareness at the youth sport level specifically.

METHOD

A total of 466 parents and 390 youth contact sport athletes from Pennsylvania and Michigan completed separate surveys of concussion knowledge and personal and family demographic information.

RESULTS

Parents had a mean concussion knowledge score of 39.3 ± 4.6 out of a possible 47 points. Having a medical occupation (p = .04) and being older in age (p = .03) were associated with higher concussion knowledge scores in parents (R² = 0.018; 95% CI = 32.77-38.99). Youth athletes had a mean concussion knowledge score of 35.0 ± 5.7 out of 47. Having learned about concussion previously (p < .001), having a history of diagnosed concussion(s) (p = .01), sport type (relative to girls' ice hockey, p < .001), older age (p < .001), and parent concussion knowledge (p = .04) were associated with higher youth athlete concussion knowledge (R² = 0.176; 95% CI = 19.08-31.72).

CONCLUSIONS

More evidence-based concussion awareness resources are needed at the youth sport level. While it did not significantly influence concussion knowledge for parents, concussion education is a modifiable factor that may be essential for improving concussion knowledge of youth athletes, thus warranting further study into effective awareness strategies for this population. Practical Applications: The factors found to influence concussion knowledge in this study could be considered in future educational concussion initiatives for youth athletes and their parents in order to increase awareness regarding the potential dangers of participating in sport while concussed.

Can Adults Recognize Concussion Symptoms? A Critical Review of Empirical Research Using the Rosenbaum Concussion Knowledge and Attitudes Survey

OBJECTIVE

The correct identification of concussion symptoms is vital for mild traumatic brain injury recognition, diagnosis, and injury management. Numerous surveys of symptom recognition have been conducted, including with athletes at-risk for injury. This critical, methodologically focused review aimed to: (1) discover which concussion symptoms are recognized, and (2) provide recommendations for future research.

DATA SOURCES

A quasi-systematic literature search was conducted to identify studies that used the Rosenbaum Concussion Knowledge and Attitudes Survey.

STUDY SELECTION

Eighty-five publications were identified, 8 of which were retained after screening.

DATA EXTRACTION

The identification of individual concussion symptoms was coded as good (a correct response by >90% of the sample), moderate (a correct response by 75%-90% of the sample), or poor (a correct response by <75% of the sample).

DATA SYNTHESIS

The pooled data comprised responses from more than 2000 individuals, most of whom were male, young adult, sport players. Overall, there was good recognition of 3 concussion symptoms (headaches, dizziness, and confusion), poor recognition of sleep disturbances, nausea, and loss of consciousness, and misattribution to concussion of 2 distractor symptoms (weakness of neck range of motion, difficulty speaking). The methodological evaluation revealed significant variability in symptom measurement.

CONCLUSIONS

The identified trends for concussion symptom recognition must be regarded as tentative because of the significant methodological variation in the reviewed studies. This variability affected the number, wording, and classification of items, and it restricted the data synthesis. This problem must be addressed in future research and recommendations are provided.

Brain trauma exposure for American tackle football players 5 to 9 and 9 to 14 years of age

American football helmets used by youth players are currently designed and tested to the same standards as professionals. The National Operating Committee on Standard and Safety requested research aiming at understanding the differences in brain trauma in youth American football for players aged five to nine and nine to fourteen years old to inform a youth specific American football standard. Video analysis and laboratory reconstructions of head impacts were undertaken to measure differences in head impact frequency, event types, and magnitudes of maximum principal strain (MPS) for the two age groups. Overall frequencies and frequencies for five categories of MPS representing different magnitudes of risk were tabulated. The MPS categories were very low (<0.08), low (0.08-0.169), medium (0.17-0.259), high (0.26-0.349) and very high (>0.35). Both cohorts experienced a majority of head impacts (>56%) at very low magnitude of MPS. Youth American football players aged 9-14 yrs. sustained a greater frequency of head impacts at MPS between 0.08 and 0.169 % associated with changes in brain structure and function. There were no differences in overall frequency, or in frequency of head impacts in other categories of MPS. The proportion of impacts considered injurious (MPS > 0.08) was greater in the 5-9 group (44%), than the 9-14 group (39%), and impacts above 0.35 % were only reported for the younger age group. The larger helmet-to-shoulder ratio in the younger age groups may have contributed to this finding suggesting that youth American football players under the age of nine would benefit from a child-specific football helmet.

An Examination of Perceived Pressure From Stakeholders on Concussion Reporting Intentions and Behavior in Ice Hockey Athletes

OBJECTIVE

We aimed to assess whether perceived pressure predicts concussion reporting intentions and behavior in youth, high school, and collegiate ice hockey athletes, and, secondarily, whether perceived pressure from stakeholders differed between sex or level of play.

SETTING

Online survey.

PARTICIPANTS

One hundred fifty-two ice hockey athletes (males: n = 96, 63.2%; females: n = 55, 36.2%; missing: n = 1, 0.7%; age = 14.04 ± 3.6 years).

DESIGN

Cross-sectional.

MAIN MEASURES

Respondents answered a survey that elicited information about demography, perceived pressure from 6 stakeholders, and concussion reporting intentions and behavior. For the first aim, we used a generalized linear model to determine whether perceived pressure from any stakeholder predicted intention (symptom reporting, concussion reporting, and intention beliefs) or behavior ("all concussions," "not obvious concussions"; α < .05) while controlling for level of play. To determine whether pressure from any stakeholder predicted symptom reporting behavior, we used logistic regression while controlling for level of play. For the second aim, to examine sex differences in perceived pressure from each stakeholder, we employed Mann-Whitney tests and to examine level of play differences, we used Kruskal-Wallis tests.

RESULTS

Controlling for level of play, a 1-point increase in perceived pressure from parents and athletic administrators decreased concussion reporting intentions by 0.92 (P = .004) and 1.09 (P = .005) points, respectively. Perceived pressure from a sports medicine professional decreased intention beliefs by 0.17 (P = .029) points. Perceived pressure from stakeholders did not predict symptom reporting (P = .440) or "not obvious concussion" reporting (P = .655) behavior. We observed no difference in perceived pressure across stakeholders (all P values >.05); however, collegiate ice hockey respondents perceived greater pressure from coaches than youth or high school athletes (P < .001). We noted no other differences in perceived pressure across levels of play (all P values >.05).

CONCLUSIONS

Concussion reporting intentions were negatively influenced by perceived pressure from parents, athletic administrators, and sports medicine professionals, but these findings did not translate to reporting behavior.

What Do Parents Need to Know About Concussion? Developing Consensus Using the Delphi Method

OBJECTIVE

Many schools and sports leagues provide preseason concussion education to parents/guardians, and in some jurisdictions, it is required for interscholastic sports participation. However, directives about content are absent or vague. The purpose of this study was to obtain expert consensus about what parents/guardians need to know to about concussion.

DESIGN

A modified Delphi process with nationally recognized expert panel members was used to obtain consensus about parent/guardian behaviors relevant to concussion prevention, identification, and management and knowledge domains relevant to performance of those behaviors.

RESULTS

Sixteen parent/guardian behaviors and 24 knowledge domains were identified. However, consensus was not achieved regarding whether it is realistic to expect parents/guardians to perform approximately one-third of the behaviors that experts agreed mattered. This variability may reflect underlying uncertainty about the capacities of some parents/guardians to put knowledge into action or the belief that there are other barriers to action. Furthermore, for most knowledge domains, there was a lack of agreement about whether or not there could be a "correct" answer on the basis of current scientific knowledge.

CONCLUSIONS

These findings raise practical and ethical questions: how can we expect parents/guardians to help prevent, identify, or manage concussion if they cannot have all the information required to engage in these behaviors due to lack of scientific consensus? This issue is not unique to concussion. Best practices for risk communication and shared decision-making can inform how we think about educating parents/guardians about concussion inside and outside of the health care setting.

Content analysis of concussion education for coaches of youth and high school sport

OBJECTIVE

Describe the extent to which concussion education provided to coaches of US high school and youth sport is inclusive of information necessary for them to engage in target behaviors related to the prevention, identification and management of concussion.

METHODS

Sport organizations included in the sample were US state high school governing bodies and national governing bodies (NGBs) for youth sports with the highest concussion incidence rates. The concussion education resources made available online for coaches by these organizations were coded for content relevant to concussion prevention, identification and management.

RESULTS

All but one state high school governing body required coach concussion education, two NGBs required coach education, seven recommended it and only one did not require or recommend it. All educational materials covered at least 84% (n = 16/19) of the relevant knowledge domains.

DISCUSSION

Existing concussion education for coaches is addressing most, but not all, topics that may help coaches engage in concussion prevention, identification and management. Additional program development work is warranted to augment educational content related to coach communication about concussion safety with athletes and parents. Content appropriateness notwithstanding, further research is needed to understand the acceptability, efficacy, and implementation of concussion education for coaches.

A systems approach to understanding the identification and treatment of sport-related concussion in community rugby union

AIM

The aim of the present study was to utilise a systems thinking approach to explore the perceived responsibilities for identifying and treating concussion held by different actors across the community rugby system (e.g., players, coaches, parents, medics, referees, and management), as well as their role-specific concussion management strategies.

METHODS

A systems approach was taken to assess what different stakeholders within rugby systems perceive their roles to be regarding concussion identification and treatment. Through an online survey, 118 members of the amateur (community) rugby union system were asked about their role-specific concussion management responsibilities and strategies. Respondents included players, parents, medics, coaches, club managers, administrators, and volunteers.

RESULTS

The majority of respondents indicated that they were able to identify the symptoms of rugby-related concussion, however, only medics stated their responsibility to use formal concussion assessments (e.g., SCAT2). A smaller number of the respondents indicated that they were involved in treating concussion within their current role/s (majority of which were medics).

CONCLUSIONS

This study illustrated that the current challenges in the identification and treatment of rugby-related concussion in community sport may be due to role/responsibility confusion and possible overreliance on field-side medics. These findings offer insight into the possible limitations of the current concussion management guidelines and may offer empirically based direction for future revisions.

School Nurses' Perceived Challenges With Concussion Management Procedures in the Secondary School Setting

School nurses have an integral role in managing student health concerns throughout the school day, yet little is known about their specific role in concussion management. Therefore, the purpose of this study was to explore the challenges encountered by school nurses regarding concussion management in the secondary school setting. Twenty-two school nurses employed in the secondary school setting were interviewed via phone. We analyzed the data via the consensual qualitative research paradigm. Overall, we found school nurses face consistent challenges with their role on the concussion management team, specifically related to education of school personnel, parents, and community health-care providers. Challenging topics included the inconsistency of community health-care provider recommendations and others' perceptions of school nurses' preparation and training to be important members of the concussion management team. Efforts to increase concussion education and improve communication across all stakeholders of the concussion management team should be implemented.

Athletic Trainers’ Perceived Challenges Toward Comprehensive Concussion Management in the Secondary School Setting

Available financial and personnel resources often dictate the specifics of concussion policies and procedures in the secondary school setting. The purpose of this qualitative study was to explore athletic trainers’ perceived challenges toward comprehensive concussion management in the secondary school setting. The findings indicate several challenges exist toward concussion management in the secondary school, including facility, personnel, and community resources, education levels of various stakeholders, and general perceptions of concussion and athletic trainers. It is important to identify challenges athletic trainers may face in order to develop strategies to align current concussion management procedures with current best practices.

Examining the psychometric properties of a sport-related concussion survey: a Rasch measurement approach

BACKGROUND

Awareness of sport-related concussion (SRC) is an essential step in increasing the number of athletes or parents who report on SRC. This awareness is important, as there is no established data on medical care at youth-level sports and may be limited to individuals with only first aid training. In this circumstance, aside from the coach, it is the players and their parents who need to be aware of possible signs and symptoms. The aim of this study was to examine the psychometric properties of a parent and player concussion survey intended for use before and after an education campaign regarding SRC.

METHODS

1441 questionnaires were received from parents and 284 questionnaires from players. The responses to the sixteen-item section of the questionnaire's 'recognition of signs and symptoms' were submitted to psychometric analysis using the dichotomous and polytomous Rasch model via the Rasch Unidimensional Measurement Model software RUMM2030. The Rasch model of Modern Test Theory can be considered a refinement of, or advance on, traditional analyses of an instrument's psychometric properties.

RESULTS

The main finding is that these sixteen items measure two factors: items that are symptoms of concussion and items that are not symptoms of concussion. Parents and athletes were able to identify most or all of the symptoms, but were not as good at distinguishing symptoms that are not symptoms of concussion. Analyzing these responses revealed differential item functioning for parents and athletes on non-symptom items. When the DIF was resolved a significant difference was found between parents and athletes.

CONCLUSIONS

The main finding is that the items measure two 'dimensions' in concussion symptom recognition. The first dimension consists of those items that are symptoms of concussion and the second dimension of those items that are not symptoms of concussion. Parents and players were able to identify most or all of the symptoms of concussion, so one would not expect to pick up any positive change on these items after an education campaign. Parents and players were not as good at distinguishing symptoms that are not symptoms of concussion. It is on these items that one may possibly expect improvement to manifest, so to evaluate the effectiveness of an education campaign it would pay to look for improvement in distinguishing symptoms that are not symptoms of concussion.

Knowledge of Concussion and Reporting Behaviors in High School Athletes With or Without Access to an Athletic Trainer

CONTEXT

Increased sport participation and sport-related concussion incidence has led to an emphasis on having an appropriate medical professional available to high school athletes. The medical professional best suited to provide medical care to high school athletes is a certified athletic trainer (AT). Access to an AT may influence the reporting of sport-related concussion in the high school athletic population; however, little is known about how the presence of an AT affects concussion knowledge, prevention, and recognition.

OBJECTIVE

To evaluate knowledge of concussion and reporting behaviors in high school athletes who did or did not have access to an AT.

DESIGN

Cross-sectional study.

SETTING

Survey.

PATIENTS OR OTHER PARTICIPANTS

A total of 438 athletes with access to an AT and 277 without access to an AT.

INTERVENTION(S)

A validated knowledge-of-concussion survey consisting of 83 items addressing concussion history, concussion knowledge, scenario questions, signs and symptoms of a concussion, and reasons why an athlete would not report a concussion. The independent variable was access to an AT.

MAIN OUTCOME MEASURE(S)

We examined the proportion of athletes who correctly identified knowledge of concussion, signs and symptoms of concussion, and reasons why high school student-athletes would not disclose a potential concussive injury by access to an AT. Frequency statistics, χ² tests, independent t tests, and linear regression were conducted to analyze the data.

RESULTS

The underreporting of concussion among high school athletes was 55%. Athletes with access to an AT had more knowledge of concussion than did athletes without such access (P ≤ .001). Chi-square tests did not demonstrate a significant relationship between AT access and a higher percentage reporting concussions.

CONCLUSIONS

High school athletes with access to an AT had more concussion knowledge, but they did not report suspected concussions to an authority figure more frequently than athletes without access to an AT.

A preliminary study of youth sport concussions: Parents' health literacy and knowledge of return-to-play protocol criteria

PRIMARY OBJECTIVE

To preliminarily explore parents' health literacy and knowledge of youth sport league rules involving concussion education and training, and return-to-play protocols.

RESEARCH DESIGN AND METHODS

This study was guided by the Knowledge, Attitude and Practice (KAP) model of health knowledge to examine parents' concussion literacy, and understanding of concussion education and training, and return-to-play protocols in youth sports. The mixed-method design involved 119 participants; that included in-person (n=8) and telephone (n=4) interviews, and web-based surveys administered through Mechanical Turk via Qualtrics (n=98).

MAIN OUTCOMES AND RESULTS

Most respondents were not familiar with concussion protocols, but trusted coaches' knowledge in return-to-play rules. More than half of the respondents report that the return-to-play concussion criteria have not been clearly explained to them. The majority of respondents were not familiar with the CDC's 'Heads Up' online concussion training programme, nor were they familiar with any other educational/training tool. About one-fifth of the parents had conversations with a coach or medical staff about youth sport concussions.

CONCLUSION

Parents have a general understanding of how to identify concussion symptoms, but lack knowledge of immediate steps to take following an incident other than seeking medical help.

Concussion knowledge among amateur motocross riders

AIM

There has been considerable increase in concussion awareness and risks; however, extreme sports such as motocross have received scant attention. The purpose of this study was to assess concussion knowledge among motocross riders and determine differences based on demographic factors.

METHODOLOGY & RESULTS

782 motocross riders responded to an Internet-based questionnaire, and participant's knowledge score was 14.3 ± 2.7 out of 20 and symptom recognition was 6.8 ± 1.4 out of 8. Riders who had performed baseline concussion testing or received formal concussion education demonstrated higher knowledge scores. Rider's demographics did not predict outcome measures.

CONCLUSIONS

Considerable misconceptions and lack of symptom knowledge persist among motocross riders and these results can be used for future interventions to improve concussion reporting.