An academic study was published today suggesting that sub-concussive events can cause brain damage in non-concussed football players. I'm not qualified to judge the scientific merits of the study, but it looks like bad news for football players. I was hoping someone in the MGoBlog community would be qualified to assess how serious and conclusive the study is.
Business week reports as follows (LINK):
Researchers at the Cleveland Clinic used blood tests, brain scans, and cognitive and other tests to assess brain trauma in 67 college football players over the course of the 2011 season. Although none of the players experienced concussions, blood tests showed that the 40 players who absorbed the hardest hits had elevated levels of an antibody linked to brain damage. These players then underwent brain scans at the University of Rochester Medical Center. When the scans were analyzed in a double-blind process, researchers found abnormalities that were predicted by the presence of the antibody.
“This positive correlation could be an early indicator of a pathological process that, with time, could perturb players’ brain health,” says Nicola Marchi, a professor of molecular medicine at the Cleveland Clinic Lerner College of Medicine, who co-authored the study with Lerner colleague Damir Janigro and Rochester’s Jeffrey Bazarian. “All football players have repeated subconcussive hits—throughout the game, the season, and their careers,” he says, but without external symptoms of injury, the hits were hard to measure. The blood tests appear to offer an early warning system.
The academic article's abstract (LINK):
The acknowledgement of risks for traumatic brain injury in American football players has prompted studies for sideline concussion diagnosis and testing for neurological deficits. While concussions are recognized etiological factors for a spectrum of neurological sequelae, the consequences of sub-concussive events are unclear. We tested the hypothesis that blood-brain barrier disruption (BBBD) and the accompanying surge of the astrocytic protein S100B in blood may cause an immune response associated with production of auto-antibodies. We also wished to determine whether these events result in disrupted white matter on diffusion tensor imaging (DT) scans. Players from three college football teams were enrolled (total of 67 volunteers). None of the players experienced a concussion. Blood samples were collected before and after games (n = 57); the number of head hits in all players was monitored by movie review and post-game interviews. S100B serum levels and auto-antibodies against S100B were measured and correlated by direct and reverse immunoassays (n = 15 players; 5 games). A subset of players underwent DTI scans pre- and post-season and after a 6-month interval (n = 10). Cognitive and functional assessments were also performed. After a game, transient BBB damage measured by serum S100B was detected only in players experiencing the greatest number of sub-concussive head hits. Elevated levels of auto-antibodies against S100B were elevated only after repeated sub-concussive events characterized by BBBD. Serum levels of S100B auto-antibodies also predicted persistence of MRI-DTI abnormalities which in turn correlated with cognitive changes. Even in the absence of concussion, football players may experience repeated BBBD and serum surges of the potential auto-antigen S100B. The correlation of serum S100B, auto-antibodies and DTI changes support a link between repeated BBBD and future risk for cognitive changes.