Study: Non-concussive hits also impact brain
Mar 6, 2013 at 4:00p ET
Football hits that do not cause concussions still can increase the risk of long-term brain damage, results of a new medical study showed this week.
The findings are eye-opening and come from a study of 67 college football players conducted by the Cleveland Clinic and the University of Rochester.
The study showed that players who were never diagnosed with concussions still had higher levels of a brain protein that leaks into the bloodstream after a head injury. Four players — none of whom had been diagnosed with concussions — showed the autoimmune response associated with brain disorders.
In short, brain damage could be caused by routine hits in the game of football. More study is needed, but the findings should resonate from NFL offices in New York to grade-school fields throughout the United States. It was released Wednesday afternoon in the online journal PLOS ONE.
“I’m not a big expert in football,” Cleveland Clinic Dr. Damir Janigro said in a recent interview. “But in a way it does (raise concerns about the sport). I think what we have unveiled is quite obvious in a way. Hitting your head against a wall is not good for the head, and the brain.
“The helmet and all the other advances in equipment protect the head, but not the brain. We found that there also are more subtle and perhaps more delayed effects from blows to the head that we should start studying.
“It’s not time to panic. But it should be looked at more.”
Janigro is director of cerebrovascular research at the clinic’s Lerner Research Institute. He and Dr. Jeffrey Bazarian of the University of Rochester Medical Center led the study. The Cleveland Clinic is actively studying ways to better diagnose and treat concussions while the NFL and colleges try to find ways to make the game safer. More than 4,000 retired players have filed suit against the NFL, charging that concussions caused long-term damage and they were never properly informed of the dangers of hits to the head.
“In recent years, there has become a sharper focus on concussions in football and other sports,” NFL commissioner Roger Goodell said in a speech at the University of North Carolina on Wednesday. “Let me make an important point here: Concussions are a global issue. Not just a football issue. We can and must do more to make the game safer, and in the process we will make other sports safer as well.”
In work done by Janigro and Bazarian, no quarterbacks were studied, but defensive linemen were “key,” Janigro said. Results showed it’s not always the easily seen, violent or high-speed hits that are of concern.
If further study confirms the finding, the very nature of some sports — including football — could be questioned.
The study involved taking blood samples from football players at Baldwin Wallace University, John Carroll University and the University of Rochester to measure the amount of the protein S100B in the blood before and after games.
Normally, S100B is only found in the brain; its presence in the bloodstream indicates damage to the blood-brain barrier, which indicates head trauma. Many European emergency rooms use an S100B test to determine if an individual has a concussion when other symptoms are not present.
The test has not been approved in the United States, though.
Once in the bloodstream, S100B is seen as an invasive substance, and the body releases antibodies to fight it. These antibodies seep back in the brain, attacking brain tissue and leading to long-term brain damage.
Four players showed signs of the autoimmune response to S100B. Brain scans showed brain damage similar to that caused in whiplash.
None of the four had been diagnosed with concussions.
“Very little is known about what sub-concussive hits do to players,” Janigro said. “We intentionally excluded all players who had a concussion during the study and focused on those on special teams or who had sub-concussive hits.”
Players were interviewed to go over the hits they felt, and those hits were confirmed by review of four cameras posted at different angles. The results “are suggestive of ongoing pathology that may increase in the future the risk of brain damage,” Janigro said.
One would think this might make people take notice.
“We not only have an acute marker for sub-concussive episodes, but we have a trail that this marker leaves, even after six months when the season is over,” Janigro said. “Fifteen percent of players had elevated auto-antibodies.”
Janigro next wants to further follow players in the study, and to study retired players to see if any loss in brain function would correlate with the antibodies.
“To see,” he said, “if we can ascribe the problems to playing the game during a younger age.”