A recent article by Churchill NW and colleagues in Neurology Vol 103 (7), Apr 8, 2025 was released in a preview form on March 12, 2025. It addresses the long term effects of concussions in athletes.
Typically, an athlete with a concussion during a sports events is evaluated for return to play (RTP) only by clinical evaluation and without imaging studies. So, we typically don’t know with a high level of confidence if there has been any meaningful brain injury.
Researchers in Canada studied college athletes in sports where concussions are not unusual (football, basketball, hockey, lacrosse, rugby, soccer, and volleyball). Of 187 athletes studied, 25 had a concussion during their sport’s season.
These 25 students were compared to 27 students without a concussion who played the same sports, were of the same sex, and had other similar characteristics.
The students all had an MRI of their brain before their sports season began. For those who had a concussion, an additional MRI was done 1-7 days post return to play (RTP), 1-3 months after, and one year after the RTP decision.
The control group of students also had MRI studies of their brain before the season began and repeat MRI studies at these same intervals.
The MRIs were compared to see whether there are any differences between the two groups. There were. Those athletes with a concussion had identifiable abnormalities on their post-concussion MRIs.
These abnormalities included changes in blood flow and tissue in the frontal lobe and other areas of the brain. These changes persisted for the entire year after RTP; later MRI studies have not been done as part of this research, so we don’t know exactly how long these changes can last.
As the lead author of the research article wrote, “The presence of significant, long-lasting brain changes after injury reinforces concerns about the consequences of repeated concussions, and to what extent these effects accumulate over time.”
Although the research did not evaluate the issue of Chronic Traumatic Encephalopathy (CTE), it is a concern in athletes who have had multiple concussions.
According to the Indiana School of Medicine, CTE is a “progressive degenerative disease in people with repeated traumatic brain injury including concussion.” We don’t know what percentage of athletes with multiple instances of concussion will eventually develop CTE.
The University lists a number of concerning symptoms from CTE: “memory loss, aggression, confusion, depression, impaired judgment, difficulty controlling impulses, erratic behavior, suicidal tendencies, anxiety, trouble sleeping, dizziness, and trouble balancing.”
CTE is a serious consequence of multiple head injuries. So far, it appears to affect only a minority of athletes with multiple concussions. However, we also don’t know if later, milder symptoms may be a result of multiple concussions.
Concussions appear to be more concerning than we used to think. Protecting athletes from concussions is an important area for research and development.
Peter M. Hartmann, MD
Family Medicine & Psychiatry
