Women at 50% Higher Risk for Sports-Related Concussion

Caroline Cassels

April 27, 2017

BOSTON — Female athletes appear to be at significantly higher risk for concussion than their male counterparts, new research shows.

Investigators at Columbia University in New York found that among college athletes of both sexes who competed in sports such as soccer, football, and basketball, women were 50% more likely to sustain sports-related concussions.

"It is unclear why women appear to be at higher risk for sports-related concussion than men. The findings from this study highlight the need for more research on the gender differences in concussion," study investigator James Noble, MD, MS, a neurologist at The Neurological Institute of New York Taubs Institute, New York City, said in a release.

Dr Noble presented the research at the American Academy of Neurology 2017 Annual Meeting (AAN) in Boston.

Understudied in Women

Sports-related concussion is a significant public health problem and represents approximately 5% of all college athletic injuries. However, depending on the sport, concussion can account for more than 20% of injuries in college athletes, the investigators report.

They also note that the research has typically focused on male athletes, and studies that have compared concussion in male and female college athletes have been limited in size and had incomplete follow-up.

Dr Noble told Medscape Medical News there are major unanswered questions in the field of concussion, including potential sex-based differences.

Columbia University Athletics has a concussion care plan that applies a standard concussion protocol to high-risk athletes, including pre/post computerized neuropsychological testing, postconcussion symptom assessments, and tracked timelines.  Dr Noble said analyzing these longitudinal data from a single center offered the investigators "a unique opportunity" to look at concussion;  its presentation, treatment, and outcomes; and possible differences between male and female athletes.

The study included 1203 athletes – 822 men and 381 women — attending Columbia University between 2000 and 2014.

During the study, a total of 228 athletes — 140 men (17%) and 88 women (23.1%) —experienced at least one concussion during their college career (P = .01). Postconcussion symptoms were similar between the two groups with the exception of amnesia (43.6% in men [n = 61] vs 30.7% in women [n = 27]; P = .052) and insomnia (29.3% in men [n = 41] vs 42% in women [n = 37]; P = .048).

The investigators found no significant difference between the sexes in postconcussion neuropsychological test performance when compared to their preinjury baseline, suggesting that women recover just as quickly as men. The average return-to-play time was 10 days for both sexes.

Athletes of both sexes who had previously sustained a concussion were three times more likely to sustain another concussion than were their concussion-free counterparts.

The fact that female athletes were more likely to have a sports-related concussion than men highlights the need to understand the reasons for this phenomenon. Dr Noble noted that there are several different but as yet unproven hypotheses.

These range from physiologic differences in the heads and necks of men and women to potential differences in the way they may report concussion.

However, he noted that "concussion continues to be a highly individualized clinical disorder, and the potential value of these findings provide additional insights and may help us counsel patients as they return to play or return to learning."

Dr Noble said the study also highlights the need for further research. Using this same data set for in future studies could offer the opportunity to examine potential links between concussion and subsequent neurologic problems and other non-neurologic problems, such as orthopedic injuries.

Male-Centric View

Commenting on the findings for Medscape Medical News, Christopher Giza, MD, a neurologist who specializes in concussion and traumatic brain injury at UCLA David Geffen School of Medicine in Los Angeles, California, said the study sheds much-needed light on an underinvestigated area.

"We have a very male-centric view of traumatic brain injury, so good studies that look at differences between males and females are helpful. If you look at the reporting for traumatic brain injury and concussion, you would definitely get the impression that 90% of head injuries occur in males, but this is not the case," he said in an interview.

Dr Giza went on to note that while both male and female athletes engage in such activities as boxing, football, rugby, ice hockey, and combat sports, the participation rates among women is much lower.

"So we get this artefactual thinking that males sustain more concussions, but it turns out that when you actually look at sports where male and female participation rates are similar and the rules are comparable, such as in soccer and basketball, you find that concussion rates in women actually exceed rates in men," he said.

On the other hand, he added, with the exception of insomnia and amnesia, rates of which were higher in men, the study showed symptoms and recovery time were very similar in both sexes.

"There are 20 or more symptoms [on concussion screening], and while women have some aspects of concussion that may be unique to their sex, at the same time they're not a different species and so a head injury is likely to be a head injury is likely to be a head injury and suggests there are commonalities in brain injury that aren't dependent on sex," said Dr Giza.

Dr Giza said more research looking into the reasons women are at higher concussion risk is required. Like Dr Noble, he noted that several hypotheses are under investigation. Key among them are the biomechanical differences between men and women.

"Concussion is a brain movement injury and so neck girth and neck strength help prevent the brain from moving. Neck girth and neck strength tends to be greater in males and so the ability to immobilize the head on impact probably gives the advantage to males," he said.

Other avenues of investigation include hormonal differences and whether progesterone and/or estrogen may be neuroprotective, but again, he said, the jury is still out.

Possible differences in the way men and women report concussion and/or bias in the way healthcare providers manage male and female athletes with concussion also warrant exploration.

For instance, he noted, one of the study's potential limitations is the fact that the researchers captured the number of concussions in the study cohort. However, he said that if there were differences between men and women in reporting or diagnosis of concussion or if some of the athletes were treated outside of the university's system, then it's possible the study's results could be affected.

In response, Dr Noble said all the athletes received their care through the Columbia system. Some may have sought additional care outside the program, but this would not have affected any of the primary epideimologic outcomes of interest, aside from recovery.

Finally, Dr Giza pointed out some conditions, such as migraine and generalized anxiety disorder, that overlap with concussion and have a female predominance. This may muddy the sex/concussion waters.

"The question is if a woman gets a concussion and has migraine or anxiety, does that potentially comorbid condition contribute to why we think women have more concussions?" said Dr Giza.

American Academy of Neurology 2017 Annual Meeting (AAN). Abstract P4.325. Presented April 26, 2017.

For more Medscape Neurology news, join us on Facebook and Twitter


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.