ARTICLE IN BRIEF
A new report found that children and young adults who resumed physical activity within the first week of an acute concussion had a reduced risk of persistent post-concussive symptoms four weeks later compared to those who did not engage in any physical activity.
Children and young adults who resumed physical activity within the first week of an acute concussion had a reduced risk of persistent post-concussive symptoms four weeks later compared to those who did not engage in any physical activity, according to a report published on December 20 in the Journal of the American Medical Association.
Current pediatric concussion guidelines, including the most recent version of the AAN's sports concussion guideline released in 2013, recommend a period of physical and cognitive rest following a concussion until post-concussive symptoms like dizziness, fatigue, headache, and irritability have resolved. Children and young adults who have sustained a concussion should not return to play until they are asymptomatic, the guidelines state, and they should increase their engagement in physical activity only if their symptoms do not worsen.
But limited evidence exists that this protocol results in positive long-term outcomes, the current study authors noted. Additionally, they pointed out, young athletes who rest for an extended period may be unnecessarily deprived of physical activity's benefits on the growing body, including its positive effects on body composition, skeletal health, and cardiorespiratory fitness. Too much rest may also lead to secondary symptoms like depression, anxiety, social isolation, and physiological deconditioning.
“We may need to reconsider the current recommendations for strict conservative rest until patients are symptom-free,” study author Roger Zemek, MD, PhD, associate professor and director of research at the University of Ottawa in Canada, said in an interview with Neurology Today. “Patients should be encouraged to participate in some form of active physical rehabilitation following concussion as long as the activity does not put them at risk of re-injury.”
In their initial unadjusted analysis, the researchers found that PPCS occurred in 24 percent of participants in the early physical activity group compared to 43.5 percent of participants in the no-activity group.
Dr. Zemek and the other study authors, led by Anne M. Grool, MD, PhD, of the department of radiology at University Medical Center Utrecht in the Netherlands, stressed that “a well-designed randomized clinical trial is needed to determine the benefits of early physical activity following concussion.”
For the current study — a secondary analysis of the prospective, multicenter Predicting Persistent Postconcussive Problems in Pediatrics study — researchers involved in the Pediatric Emergency Research Canada Concussion Team enrolled 3,063 participants between 5 and 17 years old who presented to a pediatric emergency department (ED) for an acute concussion between August 2013 and June 2015.
Patients were excluded who had a Glasgow Coma Scale score of 13 or less; an abnormality on brain imaging; who had a multisystem injury that required hospitalization; or who did not complete all assessments. The final analysis included 2,413 patients.
At the time of ED admission, researchers collected data on the study participants, including their past history of concussion; characteristics of the injury; and their pre-injury and current symptoms, encompassing physical, emotional cognitive, and sleep symptoms.
At seven days and 28 days post-concussion, researchers contacted the study participants via email or telephone and asked them to report their current level of physical activity. Their questions were based on the non-validated Zurich Consensus Statement on Concussion in Sport return-to-play steps.
Based on their responses, the researchers classified the participants into four levels of early physical activity: no activity; light activity (including light aerobic exercise such as walking, swimming, or stationary cycling); moderate activity (including sport-specific exercise like soccer drills or non-contact training drills); or full exercise (full-contact practice or a return to competition with no restrictions).
Also at seven and 28 days, the researchers asked the participants to report the severity of their post-concussive symptoms. The primary outcome measure was the presence of persistent post-concussive syndrome (PPCS), defined as at least three new or worsening symptoms on the Post-Concussion Symptom Injury scale at day 28 compared with the participants' pre-concussion status.
In their initial unadjusted analysis, the researchers found that PPCS occurred in 24 percent of participants in the early physical activity group compared to 43.5 percent of participants in the no-activity group (relative risk [RR], 0.75 [95% CI, 0.7-0.8]).
To attempt to control for potential confounding, the researchers developed a propensity score by matching the baseline characteristics – including age, gender, history, and duration of previous concussions, and type and severity of concussion – of those that did and did not participate in early physical activity. They found that early activity remained significantly associated with a lower risk of PPCS (28.7 percent) compared with no activity (40.1 percent; RR, 0.84 [95% CI, 0.65-0.84].
The study authors wrote, however, that regardless of potential benefit, caution in the immediate period after the injury is prudent. “Participation in activities that might introduce risk for collision or falls should remain prohibited until clearance by a health professional to reduce the risk for a potentially more serious second concussion during a period of increased vulnerability,” they said.
In an accompanying editorial, Sara P. D. Chrisman, MD, MPH, assistant professor, and Frederick P. Rivara, MD, MPH, professor and vice chair of academic affairs, both of the department of pediatrics at the University of Washington Medical Center, agreed that the findings show a significant difference in outcomes between the early-return group and the no-activity group. However, they cautioned that observational studies “are always limited in that they cannot presume causality. This is particularly true when the possibility of confounding by indication exists.”
Indeed, the inability to account for confounders is the study's primary limitation, said Gary Gronseth, MD, FAAN, professor and vice chair of neurology at the University of Kansas Medical Center, in an interview with Neurology Today. “The big confounder is how you're feeling at the time [of concussion],” Dr. Gronseth said. “There is no way to control for confounding caused by a kid saying ‘I'm feeling bad, I'm not going to engage in activity.’ That's a huge flaw in the study.”
A randomized trial would adjust for confounders like concussion severity, he said. “If they stratify for severity and then randomize within the strata, that's a good study design.”
“The other issues are the placebo effect and observer expectation bias,” he added. “If a randomized study compares an early versus a late return to physical activity, he said, “there has to be some sort of sham therapy given to the control group, the later activity group, that makes them expect that they'll get better, too. That may be hard.”
While he agreed that a randomized controlled trial remains the gold standard for research, Dr. Zemek responded, “Our use of propensity matching with patient characteristics statistically similar strengthens this compared to a traditional observational study.”
Dr. Gronseth agreed, noting that as observational trials go, this is a strong one. “They made a good effort to match patients for confounding variables using the propensity score,” Dr. Gronseth noted. “But there's always residual confounding.” In addition to concussion severity, he noted the participants' pre-existing educational status and social environment in the home as potential uncaptured confounders.
As for the effect the findings will have on clinical practice, two prominent sports neurologists say not much will change at their clinics, because programs like the one in the study are already in place.
“I have been doing what the study is suggesting for years,” said Andrew Russman, DO, a vascular neurologist and brain injury medicine specialist at the Cleveland Clinic. “The results of this study fit with clinical, anecdotal experience of those of us practicing sports medicine. Most sports neurologists have been practicing this way for a long time.”
Dr. Russman's clinic has a six-phase program that generally prescribes an early, graduated, return to physical activity for children and adolescents who present with a sports-related concussion. (Phases include light activity like walking, moderate activity like jogging, and moderate-heavy activity like non-contact practice or drills.) His patients may return to full activity within one week, although they may not progress by more than one phase per day. He said his experience supports that avoidance of all activity can be harmful – not just on physical health, but also on mental health.
“People may suffer depression or mood changes [as a result of concussion] because you've pulled them out of their usual activities and away from their peers,” he said. A concussed soccer player who returns to practice to engage in low-risk, non-contact agility drills “gets to be around their teammates. It brings them into contact with their social group.”
Christopher Giza, MD, FAAN, professor of pediatric neurology and neurosurgery at the University of California, Los Angeles, and director of the UCLA Steve Tisch BrainSPORT program, agreed that doctors treating concussion should avoid prolonged periods of inactivity as much as possible and encourage an individualized return to activity.
Dr. Giza and other experts agreed that the pediatric concussion guidelines should remain flexible, to reflect the individuality of concussion and of concussion recovery.
“It is quite likely that concussion treatment guidelines will never be formulaic, narrow or specific. There is a broad range of injury mechanisms, tendencies to report symptoms, criteria for diagnosing concussion and many other individualized characteristics that confound a rigid concussion protocol,” Dr. Giza said.
“People should not apply a timeline” to concussion treatment, said Dr. Russman, but should “respond to individual symptoms. Each person is different.”
And avoiding an immediate return to full-contact sport is still necessary, all agreed. “We know that people who have sustained a concussion are at increased risk of re-injury in the immediate time after that,” Dr. Gronseth said. No matter what, he said, the rule of thumb should be: “Don't go back to high-risk activities until completely recovered.”
EXPERTS: ON THE RETURN TO ACTIVITY AFTER CONCUSSION