It has been estimated that up to 20% of athletes have prolonged recoveries from concussions. These athletes could be at risk for returning to play before their brains have returned to normal. Why some athletes take longer to recover has been the focus of much research in recent years. Gender, age, the number and severity of symptoms and more have been studied to determine their influence on concussion recovery.
Now a new study suggests that genetics might play an important role in an athlete’s recovery from head injury. Research presented at the American Orthopaedic Society for Sports Medicine’s Annual Meeting examined the genetic associations involved in the physical and chemical events that occur after a head injury.
New research looks at the role of genetics and concussion recovery
The lead author of the study, Jane McDevitt, PhD, from Temple University in Philadelphia, Pennsylvania, explained that recovery is likely influenced by genetics, as genes determine the structure and function of proteins involved in cells’ resistance and response to mechanical stress.
The mechanical and chemical changes involved in a traumatic brain injury are extremely complex. In McDevitt’s words, “During a concussion, mechanical forces cause neuron cell strain that can initiate the release of glutamate and increases intracellular calcium, which leads to glutamate excitotoxicity. Genetic variation may be a factor in regulating glutamate binding and therefore cell recovery time.”
52 athletes participated in the study. Each concussed athlete underwent standardized concussion assessments following the injury. Each athlete also provided a saliva sample for genetic analysis. Each was followed until fully recovered from the concussion. The researchers then categorized the athletes into normal or prolonged recovery groups. The DNA of the athletes in each group was then studied.
The researchers found that patients with a long allele in the (GT)n genotype were 4.3 times more likely to have a prolonged concussion recovery. Clinically, this could mean that those carrying the long allele genotype may be predisposed to a greater risk of prolonged recovery.
“Making the genetic connection in this data is an exciting step for concussion injury research. Knowing this information could help improve monitoring and management of athletes who experience concussion, and may also aid in the development of genetic counseling in athletes exposed to concussive head impacts,” McDevitt observed.
How could this study help doctors – and athletes?
Obviously there is much more research needed to truly determine the significance of these findings and how to use the information in the management of head injuries in sports. If more studies confirm a link between genes and prolonged concussion recoveries, we might have some new opportunities to identify at risk athletes. Should we perform DNA screenings on all athletes as part of preparticipation physical examinations, or at least screen each athlete once in his or her career, in order to determine who is at risk for a protracted recovery period after a concussion? Should we obtain saliva samples and test for these genes in every athlete that is diagnosed with a concussion?
We clearly have much to learn, but this study seems to open up exciting avenues for future interventions. Hopefully it will help us keep more athletes from returning to play too quickly.