Children and teenagers take longer to recover from a concussion if they’ve had one before, especially within the past year, Boston Children’s Hospital emergency department physicians found in a study of 280 of their concussed patients published June 10 in Pediatrics.
The median duration of symptoms, assessed by the serial Rivermead Post-Concussion Symptoms Questionnaire (RPSQ) over a period of 3 months, climbed from 12 days in patients who hadn’t been concussed before to 24 days in those who had. The median symptom duration was 28 days in patients with multiple previous concussions, and 35 days in those who’d been concussed within the previous year, "nearly three times the median duration [for] those who had no previous concussions," according to Dr. Matthew A. Eisenberg and his associates at the hospital (Pediatrics 2013 [doi:10.1542/peds.2013-0432]).
"Similarly, patients with two or more previous concussions had more than double the median symptom duration [of] patients with zero or one previous concussion," they found.
On multivariate analysis, previous concussion, maintaining consciousness, being 13 years or older, and an initial RPSQ of 18 or higher all predicted prolonged recovery. Among all comers, 77% had symptoms at 1 week, 32% at 4 weeks, and 15% at 3 months. The mean age in the trial was 14.3 years (range, 11-22 years).
The findings were statistically significant and have "direct implications on the management of athletes and other at-risk individuals who sustain concussions, supporting the concept that sufficient time to recover from a concussion may improve long-term outcomes," the investigators said.
"However, we did not find an association between physician-advised cognitive or physical rest and duration of symptoms, which may reflect the limitations of our observational study," they added. "A randomized [controlled] trial will likely be necessary to address the utility of this intervention."
Sixty-six percent of the subjects were enrolled the day they were injured; 24.7% were enrolled 1 day later, 7.2% 2 days later, and 1.7% 3 days later. The majority (63.8%) had been injured playing hockey, soccer, football, basketball or some other sport.
The investigators defined concussion broadly to include either altered mental status following blunt head trauma or, within 4 hours of it, any of the following symptoms that were not present before the injury: headache, nausea, vomiting, dizziness/balance problems, fatigue, drowsiness, blurred vision, memory difficulty, or trouble concentrating.
The most common symptoms in the study were headache (85.1%), fatigue (64.7%), and dizziness (63.0%); 4.3% of subjects had altered gait or balance, and 2.4% had altered mental status. There were no abnormalities in the 20.8% of kids who got neuroimaging.
On discharge, 65.9% were prescribed a period of cognitive rest and 92.4% were told to take time off from sports; 63.8% were also told to follow up with their primary care doctor, 45.5% with a sports concussion clinic, and 6.2% with a specialist.
In contrast to prior studies, loss of consciousness seemed to protect against a prolonged recovery (HR, 0.648; P = .02). Maybe the 22% of kids who got knocked out were more likely to follow their doctors’ advice to rest, "thus speeding recovery from their injury. We cannot, however, eliminate the possibility that there is a biological basis to this finding," the team noted.
Subjects who were 13 years or older might have taken longer to recover (HR, 1.404; P = .04) because games "between older children involve more contact and higher-force impacts," although neurobiologic differences between older and younger kids might have played a role, as well, the investigators said.
"Female patients" – about 43% of the study total – "had more severe symptoms at presentation in our study (mean initial RPSQ of 21.3 vs. 17.0 in male patients, P = .02). ... Whether this finding is indicative of the fact that female patients have more severe symptoms from concussion in general, as suggested in several previous studies, or is due to referral bias in which female individuals preferentially present to the ED when symptoms are more severe ... cannot be ascertained from our data," they noted.
Female gender fell out on multivariate analysis as a predictor of prolonged recovery (HR, 1.294; P= 0.11).
The investigators said they had no relevant financial disclosures.