Concussions are more than twice as prevalent among college students than previously believed and significantly more likely to occur off the playing field than on, according to a three-year study published Dec. 18 in the journal JAMA Network Open.
The research, which looked at student health data from the University of Colorado Boulder, also found that incidence is slightly higher among females, and more concussions occur in August than any other month.
"This study shows how common head injuries are among this population and that concussions are not restricted to the athletic field," said Dr. John Breck, study co-author and lead physician for CU Boulder Medical Services. "Student health centers around the country should be training their staff in concussion recognition and putting systems in place to help concussed students get the evaluation and treatment they need."
The research, among the first to assess rates among the general college-age population, tracked concussion diagnoses during the academic year at the Wardenburg Student Health Center from August 2015 to May 2018 and through the CU Sports Medicine department, which treats varsity athletes, from 2016 to 2018.
In all, among roughly 30,000 public university undergraduates, about 340 concussions are diagnosed annually - an incidence rate of about one in 75 students per year, the study found.
Notably, 41% of students diagnosed said they had already had between one and three concussions; 5% reported four or more.
Across all years, whether varsity athletes were included or not, non-sport-related concussions outnumbered sport-related concussions.
Among the general undergraduate population, excluding varsity athletes, 64% of concussions were non-sport-related, while the remainder were sustained during organized competitive sports, such as club sports. Falls, such as slips on the ice or crashes on skateboards, accounted for 38% of concussions. Hits to the head, such as those sustained in a fight or accident, constituted 8.5%. Meantime, 6.5% resulted from motor vehicle accidents.
When varsity athletes were included, sport-related concussion incidence was 51 per 10,000 students per year and non-sport-related concussion incidence was 81 per 10,000 students per year. Overall concussion incidence was 132 per 10,000 students per year.
"There is a widely held perception that most concussions are sport-related. Our study shows it can happen to anyone, male or female, engaged in a variety of activities," said co-author Matt McQueen, an integrative physiology professor.
The study also found that, across all three years, concussion incidence soared in August.
"These data do not tell us why August had such high numbers, but anecdotally we know that August is a time of lower academic demand and higher risk-taking behavior," said Breck.
Among varsity athletes, females had a higher rate of concussion, with 54 females and 26 males sustaining concussions across two academic years. This finding is consistent with another recent study which found that concussions among females increased six-fold from 2003-2013, while the increase among males was 3.6-fold.
While it's uncertain exactly why females appear to be more susceptible to concussions, hormonal differences and differences in neck strength and head mass may play a role, said Breck.
Prior research by the Centers for Disease Control and Prevention found concussion incidence rates among 9 to 22-year-olds to be around 98 per 10,000 people per year. The World Health Organization has pegged rates for the general population at around 60 concussions per 10,000. The new study, which looked at only nine months, found it to be more than twice that.
"Our findings suggest that collegiate students, including the general population and varsity athletes, may be at an increased risk of concussion," the authors concluded.
They noted that previous studies relied either on survey self-reports, emergency room visits, or focused on varsity players, possibly resulting in an under-estimate. Greater awareness could also be encouraging more students to seek care - and that's a good thing, the authors say.
"Missing class and falling behind due to a head injury can be a significant detriment to a student's academic success," said Breck. "It's critical that they get high quality, evidence-based care as soon as possible so they can return to learning in a safe way with as little disruption in their education as possible."