Expert Q&A

For college athletes, three or more concussions can result in significantly worse brain health five years after their playing days are over, according to a new study in the journal Neurology.

Co-lead author Adrian Boltz, a doctoral candidate at the University of Michigan School of Kinesiology and member of the Michigan Concussion Center, says the study is different from others because most research in this space examines people in their 50s or 60s—decades after sport participation. Instead, this study looks at college athletes in their 20s, and researchers already see the impact of concussion, which enables early intervention.

Boltz and colleagues, including co-lead author Landon Lempke of Virginia Commonwealth University and principal investigator Steven Broglio of the Michigan Concussion Center, looked at more than 3,900 former college athletes from 20 sports, the majority at NCAA Division 1 schools, five years after graduation.

They also found that athletes with 1-2 concussions fared slightly worse on various self-reported physical, mental, behavioral and cognitive health tests when assessed five years after leaving their sport. Encouragingly, most remained within normal ranges for brain health.

Boltz discusses the findings from the study, which was funded by the National Collegiate Athletic Association (NCAA)-Department of Defense Concussion Assessment, Research and Education (CARE) Consortium.

Does early detection give people a longer window to start good habits?

Yes. Early detection allows us to emphasize behaviors known to be associated with positive brain health, like physical activity, healthy diet, mental health,and perhaps most overlooked, sleep habits, for these individuals earlier in life. Starting earlier provides a longer window to establish these habits and potentially mitigate any adverse trajectories. If there is an association with poorer later-life outcomes, these behaviors may represent accessible mechanisms that may help reduce the likelihood of those outcomes occurring.

People might worry that brain health was worse just five years after leaving their sport. Can you put this into context for readers?

I think it’s important to note that there’s a difference between a research finding and a clinical diagnosis, and it’s easy for those lines to get blurred. What we found is that former college athletes with three or more concussions scored slightly worse on some health measures compared to former athletes with no concussion history. But even in that group, their median scores were still within a normal health range, potentially indicating that they didn’t cross the threshold that would flag someone as having a clinical problem.

What’s more, we also didn’t specifically examine whether concussion history could predict who would exceed those clinical thresholds. So while scores were worse in the three or more concussions group, that doesn’t necessarily mean they crossed into clinically concerning territory. It’s also worth noting an important consideration: we used self-reported tests, meaning participants answered questions about how they felt or functioned. These tools are valuable, but they are also imperfect. People may underestimate or overestimate their own health, sometimes without even realizing it.

Did any of these findings surprise you?

Not exactly. I think we had anticipated some sort of association between concussion history and performance on these tests. One thing that stood out was that these associations were wide-ranging, in that concussion history wasn’t just associated with one specific area, but rather showed up across multiple domains. This is consistent with our current understanding of how concussion-related injuries impact the brain. When the brain experiences that kind of trauma, the effects tend to be spread out rather than concentrated in one place. So while it’s always important to verify these things in research, we weren’t caught off guard by what we found.

Playing a high-contact sport wasn’t automatically associated with worse outcomes, correct?

One thing that might surprise people is that simply playing a high-contact sport wasn’t automatically associated with poorer scores on these health measures. What really seemed to be important was whether you had a history of concussion, and how many.
Most people might expect high-contact sport athletes to have worse health outcomes across the board, but the data tells a different story. It was concussions, not just the contact associated with a sport, that were most often associated with differences in health.

Does this mean that high-contact sports like football and hockey are safer than we thought because people who played it didn’t have worse brain health? How should this study be taken?

This is an interesting question, but unfortunately not one that this study can directly answer. What we did find was that sport contact level was not the strongest nor most common predictor of differences in health, concussion history was. And while football and hockey are sports where concussion commonly occurs, it’s important to note they are not the only sports in which concussions happen.

We also tested whether the combination of playing high contact sport and having a concussion together resulted in a different association than either factor alone, but we didn’t observe any evidence of that. Still, that doesn’t mean that high-contact sports may be without risk.

What is the takeaway when it comes to contact level and concussion?

And so, what this really points to is the importance of concussion prevention, recognition, and proper management across all sports, regardless of contact level. The takeaway is not that we should be less concerned about high-contact sports, but rather that concussions are what we really need to be focused on preventing and improving recovery from.