Do Adolescent Concussions Cause Multiple Sclerosis?

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With so many news stories reporting on the long-term brain damage among professional football players, it is only natural that parents, youth league organizers and child health advocates want to make sure our youngest athletes are protected from similar problems. So when a recent large-scale study revealed that people who had suffered concussions as adolescents had a higher risk of later developing multiple sclerosis, the collective worry over traumatic brain injuries was heightened.

The new study, published in Annals of Neurology by scientists at Orebro University, the Karolinska Institute in Sweden and other institutions, looked at every person in Sweden who had been given a multiple sclerosis diagnosis since 1964. In that group of 7,292 men and women with a diagnosis of MS, an autoimmune nervous system disorder with an unknown cause and no cure, researchers found that adolescents who had suffered one concussion were 22 percent more likely to later develop MS than those who had not. That risk jumped by about 150 percent if a young person had had multiple concussions.

While such results are alarming and should be taken seriously, Dr. Michael E. Hoffer, a balance disorder and concussion management expert with the University of Miami Health System, cautioned that such study results need to be taken in context.  “Can there be long-term damage [due to a concussion]?” he asked. “Yes, certainly, but also you have to factor in genetics and other experiences.  There are so many others things that can damage the system that it’s difficult to pinpoint just one.”

In other words, the possible link between head injuries during the teen years and the eventual development of MS as an adult does not mean one causes the other.  As the researchers noted, many of those who had suffered concussions never developed MS.  Thus, the explanation for the link could be as simple as a genetic susceptibility to the condition, as Hoffer suggested, or some underlying factor that is triggered by a blow to the head.

Hoffer would like to see the debate on concussions directed at more practical matters than a study that might panic parents.  “I think it’s important that we avoid discouraging kids from youth sports,” he adds. “There are many more advantages to participating and being active than to not participating. The issue is not that there are more head injuries, but that sports are safer than ever.”

Actually, the playing field isn’t even the most dangerous venue for teens and young adults when it comes to suffering a traumatic brain injury.  Concussions can also occur as a result of motor vehicle crashes, being struck by or against an object, falls, and assaults. In fact, teens and young adults have the highest rates of motor-vehicle-related TBIs. Contact sports also qualify as culprits, of course, with more than 70 percent of sports and recreation-related ER visits for concussions occurring in youth ages 10 to 19.

Many people, Hoffer notes, blame football specifically, but “female sports can be almost as dangerous as male sports.” Any direct or indirect blow can jostle the brain inside the skull, disrupting normal neurological and metabolic functions temporarily. You don’t even have to hit your head — whiplash can cause one — or lose consciousness to have sustained a concussion. While football does have the highest average annual concussion rate, girls ice hockey and soccer also have elevated rates, as does boys’ wrestling.  What’s more, in comparing rates in sports such as basketball, soccer, and baseball/softball, young women reported almost double the annual rate as their male counterparts.

Still, there is some encouraging news. Another recent study published online in the American Journal of Public Health found that repeat concussions had gone down between 2009 and 2014, likely a result of concussion laws passed in all 50 states that required mandatory removal from play after a suspected concussion, clearance to return to play from a licensed health professional, and required education of coaches, parents and athletes about concussion symptoms and signs. As expected, first-time concussions went up because more were being reported under the law, but the requirements for mandatory removal from play or for permission to return to play probably reduced recurrent concussions.

The importance of avoiding a second or multiple concussions is very important, as a child who suffers a concussion is one and a half times more likely to experience another, and those who have had two concussions have a threefold greater risk of the same injury happening again.

“There is a growing awareness of concussions and the need to identify and manage them appropriately,” Hoffer says, pointing to the groundbreaking work done by his UM colleague, Gillian Hotz, who leads the University of Miami Sports Medicine Institute’s new Pediatric Concussion Clinic. (Hotz and UM also developed a pioneering partnership with Miami-Dade County Public Schools to make concussion awareness, prevention, and treatment a priority for Miami-Dade’s student-athletes.)

Hoffer worries that the increased attention to concussions, while good, also leads to untrained medical professionals claiming to be experts in the field. When this happens, he adds, children and adolescents aren’t getting the treatment they need for proper recovery. He favors a multidisciplinary team approach, with experts in a variety of fields managing care. Personalized treatment plans, and not a one-size-fits-all program, should be developed with an emphasis on how young people’s physical and school performance can be affected.

Hoffer and other researchers from the University of Miami Miller School of Medicine are working with the I-Portal Neuro Otologic Test, which uses the head-mounted goggle to gauge eye movement through video cameras and computers. It can successfully diagnose a concussion with 95 percent specificity and 89 percent sensitivity, a vast improvement from the usual physical exams that are typically used to diagnose mild traumatic brain injuries.

“The long-term damage [of a concussion] can be minimized,” Hoffer adds, “but we have to focus on correct and early diagnoses and factors beyond. It’s very important patients see the proper doctors and get the proper treatment.”


In Their WordsAna Veciana Suarez
Ana Veciana-Suarez, Guest Contributor

Ana is a regular contributor to the University of Miami Health System. She is a renowned journalist and author, who has worked at The Miami HeraldThe Miami News and The Palm Beach Post. Visit her website at anavecianasuarez.com or follow @AnaVeciana on Twitter.