https://pixabay.com/photos/brain-question-mark-alzheimer-s-2546101/

Background

Head injury is a common complaint in patients presenting to the Emergency Department. A subset of these patients will ultimately be diagnosed with a concussion, which is a symptom complex that can develop in patients with a mild traumatic brain injury. While most concussion patients have short-lived neurologic impairment, there is increasing new evidence of long-term neurologic sequelae in some patients. This new concern over the enduring cognitive impact of concussions (and evidence demonstrating that approximately 20% of middle and high school children in the US[1,2] will experience a concussion) has made concussions a target of renewed attention and scrutiny in both the medical literature and the mainstream media.

Despite the widespread prevalence of concussions, little is known about its ideal management. The traditional recommendation for concussion treatment has centered around the concept of “brain rest” in addition to physical rest. There is little medical evidence to support this recommendation. Our journal club sought to answer whether some physical activity could actually benefit patients with acute concussion and additionally reviewed a study (completed in Maine) that challenged the belief concussions have long term cognitive effects. Read on to see what you think!

Articles reviewed

Brooks, et al. Multiple Past Concussions in High School Football Players: Are There Differences in Cognitive Functioning and Symptom Reporting? American Journal of Sports Med. 2016 December; 44(12): 3243-3251.[Pdf]
Grool, et al. Association Between Early Participation in Physical Activity Following Acute Concussion and Persistent Postconcussive Symptoms in Children and Adolescents. JAMA. 2016; 316(23): 2504-2514.[Pdf]
Leddy, et al. Early Subthreshold Aerobic Exercise for Sport-Related Concussion. A Randomized Clinical Trial. JAMA Pediatrics. 2019 Apr; 173(4): 319-325. [Pubmed Free Text]

BROOKS ET AL.

Performed in our very own state of Maine, this observational retrospective study included 5,232 Maine high school football players and sought to evaluate the effect of concussion history on cognitive functioning, as tested by the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery. Analyses showed there was no significant difference between groups of athletes, determined by number of self-reported concussions, in testing performance. A history of concussions was independently related to symptom reporting, most commonly headache and sensitivity to light and noise. Interestingly, symptom reporting was more closely tied to having a history of developmental disorders (of attention and learning), past psychiatric history, or a significant history of headaches and migraines, as opposed to concussion history. The main limitation of this study was the self-reported nature of the concussion histories of the participants.

Bottom line: History of prior concussions is not a predictor of cognitive functioning deficits in high school athletes.

GROOL ET AL.

This prospective, multicenter cohort study funded by the Canadian Institutes of Health investigated post-concussive symptom improvement and compared early physical activity to no physical activity. The measured outcome was persistent post-concussive symptoms per Post-Concussion Symptom Inventory at day 28 post injury, and demonstrated a favorable association between early physical activity and diminished persistent post-concussive symptoms as compared to a no physical activity group (24.6% vs 43.5%). This study, however, has numerous limitations, primarily a lack of randomization of groups, with no determination of causation of demonstrated associations.

Bottom Line: There is a favorable association between early physical activity and persistent post concussive symptoms, however implications of this are entirely limited due to unclear causation.

LEDDY ET AL

This multi center prospective randomized clinical trial evaluated the effectiveness of subsymptom threshold aerobic exercise vs a placebo-like stretching program in recovery from sports related concussion (SRC) in adolescent athletes. Measured outcome was days from injury to recovery, defined as being asymptomatic, confirmed recovery by a physician blinded to treatment groups and being able to return to normal exercise tolerance. Aerobic exercise participants recovered in a median of 13 days, whereas stretching participants recovered in 17 days (P= .009). The study also classified participants as having normal (<30 days) or delayed (>30 days) recovery. The aerobic exercise group was found to have a nonsignificant lower incidence of delayed recovery in comparison to the placebo group (2 participants [4%] in the aerobic group vs 7 [14%] in the placebo group, P= .08).

Kaplan-Meier Estimates of Time to Recovery Survival analysis comparing groups; the aerobic exercise group recovered significantly faster than the stretching group after adjusting for age, sex, time from injury to first clinical visit, and concussion… — Kaplan-Meier Estimates of Time to Recovery Survival analysis comparing groups; the aerobic exercise group recovered significantly faster than the stretching group after adjusting for age, sex, time from injury to first clinical visit, and concussion history (z = 2.82; P = .005).

Bottom Line: Recommending that adolescent patients with sports related concussion begin subsymptom aerobic exercise may lead to a shortened time to recovery.

These studies provide good evidence that emergency providers advising athletes to refrain from any and all physical activity may not be in their best interest. While they clearly still need to be cleared by their primary providers to return to full participation, they may note improvement in symptoms with restarting low aerobic levels of activity. While these studies did not hypothesize on why activity may be beneficial. We theorize that the endorphins related to physical activity, in addition to the psychosocial implications of restarting components of daily adolescent life could be behind this effect. Lastly, while the Brooks et al study did not find that a history of concussions was related to cognitive functioning deficits among high school athletes, it is in contrast with the findings of many other studies. This could be due to limitations in the methodology or the fact that these athletes were analyzed during high school, as opposed to multiple studies that examine professional athletes. We hope this journal club provides emergency providers with a new perspective on how counselling adolescent patients with acute concussion.

References

1. Prevalence of Concussion Among US Adolescents and Correlated Factors. AU Veliz P, McCabe SE, Eckner JT, Schulenberg JE SO JAMA. 2017;318(12):1180.[Full Text]

2. Lifetime Prevalence of Self-Reported Concussion Among Adolescents Involved in Competitive Sports: A National U.S. Study. AU Veliz P, Eckner JT, Zdroik J, Schulenberg JE SO J Adolesc Health. 2019;64(2):272. Epub 2018 Nov 5.[PubMed]

Written by Casey Z. MacVane, MD, MPH, Jacques Larochelle, MD, Michael Leslie, MD and John McNamara, MD

Edited and Posted by Jeffrey A. Holmes, MD