After a concussion, women tend to have worse symptoms than men. That's the case even when athletes were injured playing the same sport, according to a new study of young soccer players.
Some recent studies have found gender differences in memory and other symptoms after concussions, with women generally doing worse.
The new results support findings that women take longer to recover than men, Tracey Covassin said. She led the study at Michigan State University in East Lansing.
"Results from this study may impact sports medicine clinicians on being more cautious when returning female concussed soccer athletes back to participation," Covassin said.
"Moreover, healthcare professionals need to be aware that females could report more total concussion symptoms compared to male concussed athletes," she added.
The researchers looked at 39 male and 56 female soccer players who sustained a concussion. All were in high school or college.
The athletes took computer tests that measured their learning and memory skills, reaction time and physical symptoms before the soccer season started and again eight days after their concussion.
On the preseason tests, men and women scored fairly similarly.
But eight days after their concussions, women scored lower on a test that measures a person's ability to remember visual images - 69 percent, on average, compared to 77 percent among men. Scores on other thinking and memory tests were still comparable.
Women also reported more total symptoms post-concussion than men.
Both men and women said they had minimal amounts of body pain or mood changes. But women reported migraines and sleep difficulties more than twice as often as men, according to results published in the American Journal of Sports Medicine.
"This study presents data from a large bank of injuries in a young population and those data will ultimately help answer some of the questions of how and why there are differences," Susan Saliba said.
Saliba is a physical therapist, athletic trainer and associate professor at the Curry School of Education at the University of Virginia in Charlottesville. She was not involved in this study.
One very similar recent study did not find thinking and memory differences between men and women after a concussion.
The author of that study, Dr. Scott Zuckerman, was surprised the results did not align.
"It's a well-done study, and thorough, but we can't draw global conclusions from the body of evidence yet," Zuckerman, from Vanderbilt University Medical Center in Nashville, Tennessee, said.
The only difference in the studies was that this time, Covassin and her colleagues accounted for athletes' body mass index (BMI), a measure of weight relative to height, in their results.
They suggest larger people have more neck strength and are better able to stabilize the head on impact, suffering a less severe concussion as a result. But in their study, women had a slightly higher average BMI than men, yet had poorer memory recovery and more symptoms post-injury.
At the moment, theories on the role of body size in concussion recovery are just that: theories.
"I do believe that size can contribute to concussion severity, incidence and recovery, but I'm not sure how," Saliba said. "Larger individuals may have better neck strength, but they also have more mass, which is a factor in transmitting force."
Other ongoing studies are investigating this issue, she said.
"Teachers, parents and athletes need to be aware of all the signs and symptoms of a concussion in order to recognize an athlete who incurs a concussion," Covassin said.
Although there may be differences in symptoms between men and women, she said, it's more important to know that every concussion, and every athlete, is unique and requires individualized treatment.