Sensitivity and Specificity of Exercise Intolerance on Graded Exertion Testing for Diagnosing Sport-Related Concussion: A Systematic Review and Exploratory Meta-Analysis.

Abstract There is no single gold standard test to diagnose sport-related concussion (SRC). Concussion-related exercise intolerance, that is, inability to exercise to the individual's appropriate level due to exacerbation of concussion-like symptoms, is a frequent finding in athletes early after SRC that has not been systematically evaluated as a diagnostic test of SRC. We performed a systematic review and proportional meta-analysis of studies that evaluated graded exertion testing in athletes after SRC. We also included studies of exertion testing in healthy athletic participants without SRC to assess specificity. Pubmed and Embase were searched in January 2022 for articles published since 2000. Eligible studies included those that performed graded exercise tolerance tests in symptomatic concussed participants (> 90% of subjects had an SRC, seen within 14 days of injury), at the time of clinical recovery from SRC, in healthy athletes, or both. Study quality was assessed using the Newcastle-Ottawa Scale. Twelve articles met inclusion criteria, most of which were of poor methodological quality. The pooled estimate of incidence of exercise intolerance in participants with SRC equated to an estimated sensitivity of 94.4% (95% confidence interval [CI]: 90.8, 97.2). The pooled estimate of incidence of exercise intolerance in participants without SRC equated to an estimated specificity of 94.6% (95% CI: 91.1, 97.3). The results suggest that exercise intolerance measured on systematic testing within 2 weeks of SRC may have excellent sensitivity for helping to rule in the diagnosis of SRC and excellent specificity for helping to rule out SRC. A prospective validation study to determine the sensitivity and specificity of exercise intolerance on graded exertion testing for diagnosing SRC after head injury as the source of symptoms is warranted.

Practical Management: A Standardized Aerobic Exercise Program for Adolescents With Concussion in the Absence of Graded Exercise Testing.

ABSTRACT: Aerobic exercise is safe and beneficial for adolescent athletes recovering from sport-related concussion (SRC). The results of systematic graded exercise testing are used to create individualized, subsymptom heart rate threshold (HRt) aerobic exercise treatment programs for adolescents after SRC. Many clinicians, however, do not have access to graded exercise tests. This article presents a safe, systematic, evidence-based exercise program that clinicians can prescribe, progress, and modify to help manage acute pediatric SRC without the need for formal exercise testing. The exercise prescription accounts for sex and days since injury but not age because our analysis indicates age does not significantly affect the HRt on graded exercise testing. This article provides clinicians without access to graded exercise testing a viable option for prescribing exercise treatment to adolescents in the early phase after SRC.

Service Delivery Models for the Management of Pediatric and Adolescent Concussion: A Systematic Review.

Objective: To examine the current peer-reviewed literature on pediatric concussion and mild traumatic brain injury (mTBI) service delivery models (SDMs) and relevant cost analyses. Data Sources: PubMed, Embase (Elsevier), CINAHL Plus (EBSCO), APA PsycINFO (EBSCO), and Web of Science Core Collection, limited to human trials published in English from January 1, 2001, to January 10, 2022. Study Selection: Included articles that (1) were peer-reviewed; (2) were evidence-based; (3) described service delivery and/or associated health care costs; and (4) focused on mTBI, concussion, or postconcussion symptoms of children and adolescents. Studies describing emergency department-based interventions, adults, and moderate to severe brain injuries were excluded. Data Extraction: The initial search resulted in 1668 articles. Using Rayyan software, 2 reviewers independently completed title and abstract screening followed by a full-text screening of potentially included articles. A third blinded reviewer resolved inclusion/exclusion conflicts among the other reviewers. This resulted in 28 articles included. Data Synthesis: Each of the 28 articles were grouped into 1 of the following 3 categories: generalist-based services (7), specialist-based services (12), and web/telemedicine services (6). One article discussed both generalists and specialists. It was clear that specialists are more proactive in their treatment of concussion than generalists. Most of the research on generalists emphasized the need for education and training. Four studies discussed costs relevant to SDMs. Conclusions: This review highlights the need for more discussion and formalized evaluation of SDMs to better understand concussion management. Overall there is more literature on specialist-based services than generalist-based services. Specialists and generalists have overarching similarities but differ often in their approach to pediatric concussion management. Cost analysis data are sparse and more research is needed.

Association of Concussion History and Prolonged Recovery in Youth.

OBJECTIVE: To determine the number of prior concussions associated with increased incidence of persistent postconcussive symptoms (PPCS) in a cohort of acutely concussed pediatric patients. DESIGN: Prospective observational cohort study. SETTING: Three university-affiliated concussion clinics. PARTICIPANTS: Two hundred seventy participants (14.9 ± 1.9 years, 62% male, 54% with prior concussion) were assessed within 14 days of concussion and followed to clinical recovery. Participants with a second head injury before clinical recovery were excluded. MEASURES AND MAIN OUTCOME: Concussion history, current injury characteristics, recovery time, and risk for prolonged recovery from current concussion. RESULTS: There was no statistically significant change in PPCS risk for participants with 0, 1 or 2 prior concussions; however, participants with 3 or more prior concussions had a significantly greater risk of PPCS. Twelve participants sustained a subsequent concussion after clinical recovery from their first injury and were treated as a separate cohort. Our secondary analysis found that these participants took longer to recover and had a greater incidence of PPCS during recovery from their latest concussion. CONCLUSION: Pediatric patients with a history of 3 or more concussions are at greater risk of PPCS than those with fewer than 3 prior concussions.

Adolescents with Sport-Related Concussion Who Adhere to Aerobic Exercise Prescriptions Recover Faster.

PURPOSE: There is growing evidence that subsymptom threshold aerobic exercise speeds recovery from sport-related concussion (SRC). It is not known whether there is a direct relationship between adherence to a personalized exercise prescription and recovery or if initial symptom burden affects adherence to the prescription. METHODS: This study was a planned secondary analysis of one arm of a randomized controlled trial. Male and female adolescent athletes (age 13-18 yr) presenting within 10 d of SRC were given aerobic exercise prescriptions based on their heart rate threshold at the point of exercise intolerance on a graded treadmill test. Adherence was determined objectively with HR monitors and compared against time to recovery. Participants who completed at least two-thirds of their aerobic exercise prescription were considered to be adherent. RESULTS: Sixty-one percent of adolescents met the adherence criterion. Those who were adherent were more symptomatic and were more exercise intolerant at their initial visit, yet they recovered faster than those who were not adherent (median recovery time, 12 (interquartile range, 9-22) d vs 21.5 (interquartile range, 13-29.8) d; P = 0.016). On linear regression, adherence during week 1 was inversely related to recovery time ( ß = -0.002 (-0.003, 0.0), P = 0.046) and to initial exercise tolerance ( ß = -0.886 (-1.385, -0.387), P < 0.001), but not to initial symptom severity ( ß = 0.545 (-0.232, 1.323), P = 0.146). No adverse events or near misses were reported. CONCLUSIONS: Adherence to individualized subsymptom threshold aerobic exercise within the first week of evaluation is associated with faster recovery from SRC. The data suggest that initial degree of exercise intolerance, but not initial symptom severity, affects adherence to aerobic exercise prescribed to adolescents within 10 d of SRC.

Sex differences in the Buffalo Concussion Treadmill Test in adolescents with acute sport-related concussion.

OBJECTIVES: The Buffalo Concussion Treadmill Test (BCTT) is a safe and validated tool to assess exercise tolerance after sport-related concussion (SRC). Sex differences may affect the interpretation of this systematic exertion test in the concussed population, which is important for clinicians. The purpose of this study was to examine sex differences in BCTT performance in adolescents with acute SRC. DESIGN: Prospective cohort. METHODS: Male (n = 103, 15.3 ±â€¯2 years) and female (n = 87, 15.1 ±â€¯2 years) adolescents with SRC performed the BCTT within 10 days of injury. Heart rate (HR), HR threshold (HRt), Delta HR (difference between resting HR and HRt), symptom severity on Visual Analog Scale (VAS) and symptoms exacerbated on the BCTT were collected and compared. RESULTS: Males had lower resting HR (M: 70.9 ±â€¯12 vs F: 75.7 ±â€¯13 bpm, p < 0.01) and reached a lower HRt than females (M: 134.7 ±â€¯23 vs F: 141.5 ±â€¯25 bpm, p = 0.05). Sexes did not differ on Delta HR (M: 63.8 ±â€¯26 vs F: 65.9 ±â€¯24 bpm, p = 0.57), total treadmill time (M: 9.3 ±â€¯5 vs F: 8.4 ±â€¯4 min, p = 0.20), maximum VAS (M: 5.0 ±â€¯2 vs F: 5.4 ±â€¯2, p = 0.18) or incidence of a change in VAS (M: 91% vs F: 94%, p = 0.43) on the BCTT. CONCLUSIONS: Although males may reach symptom exacerbation at a slightly lower mean HRt than females on the BCTT within 10 days of SRC, the BCTT provides comparable information and both sexes reach symptom exacerbation at similar Delta HR.