Symptom Recurrence After Concussion Depends on Risk Factors
Tracey Romero • Wed, November 1st, 2017
In a recent study, “Sport-Related Concussions: Symptom Recurrence After Return to Exercise,” published in the October 2017 issue of Orthopaedic Journal of Sports Medicine, Michael O’Brien, M.D., sports medicine physician and director of the Sports Concussion Clinic, Boston Children's Hospital, identified risk factors for symptom recurrence upon return to play after a sports-related concussion.
In this case-control study, O’Brien and his colleagues collected data on patients at a sport concussion clinic between October 1, 2009 and July 31, 2011. The main variable in the study was the recurrence of symptoms with exercise after being symptom-free at rest at some point in their recovery. Other important data included age, sex, loss of consciousness with injury, prior concussion (diagnosed and undiagnosed), Post-Concussion Symptom Scale (PCSS) score, time until clinical presentation, and duration of symptoms.
Of the 217 patients included in the study, 25 (12%) experienced a return of symptoms. The majority of the 25 patients who had a recurrence experienced it during game play (n = 7) or during minimal non-contact activity (n=6). During moderate non-contact exercise, four of 25 patients had a recurrence of symptoms.
The researchers found that symptoms were more likely to recur during physical activity in those athletes who had a previous undiagnosed concussion, those who did not lose consciousness at the time of injury, those who reported to the clinic earlier after the injury, and those who had a longer duration of concussion symptoms at rest.
O’Brien told OTW, “There is a growing body of evidence that shows that it is safe and effective to introduce light to medium, graded non-contact exercise with an emphasis on avoiding symptom exacerbation (that is, staying at a ‘subthreshold level of exercise’). The addition of small amounts of exercise can help prevent the detrimental effects of excessive rest, like feeling sluggish and deconditioned. It may help stimulate metabolic changes that help the body and brain recover.”
He added, however, that the study “points out some factors that might suggest the risk of symptom recurrence after initial recovery, and therefore the treating clinicians may take a more gradual and conservative approach to prescribing an exercise progression in patients with those risk factors.”