A new study finds concussion in teenagers increases the risk of multiple sclerosis in later life. However, there is no link with MS for concussion in younger children. The authors said the results demonstrate how important it is to protect teenagers from head injuries.
 
A collaborative study between Örebro University and Karolinska Institutet showed concussion in adolescence increased the risk of MS in later life by 22 percent for one concussion, and teenagers who experienced two or more concussions were at more than a doubled risk of MS – 133 percent.
 
The researchers used medical records to identify concussion treated in hospital among children from birth to age 10 years; and in adolescence from ages 11 to 20. The risk of MS in later adulthood was examined for these two groups. Differences in the way the brain is developing in childhood and adolescence may explain why concussion in these two age groups does not carry the same risk of subsequent MS.
 
The next step is to investigate genetic influences, including how genes interact with other factors to determine MS risk. This includes looking at how genes influence the risk of MS associated with concussion in adolescence, as well as examining other exposures among teenagers, such as infections.
 
Researchers caution that ways should be considered to reduce the risk of head injury, especially repeated head injuries, when participating in sport. They said that MS is caused by a combination of genetic susceptibility and environmental exposures. Most of the young people who experience a head trauma should not worry as they will not carry the necessary genes and other risks that will result in MS in later life.
 
The study was published in the Annals of Neurology.