Ice hockey players in Sweden with sports-related concussions had higher levels of the blood biomarker total tau, suggesting the central nervous system protein might be a tool for diagnosing concussions and deciding when athletes can return to competition.
Concussion or mild traumatic brain injury in athletes who play competitive contact sports, such as hockey, football and boxing, is a growing problem, according to background information in the study, which was published March 13 on the website of JAMA Neurology. While mild concussions generally cause no loss of consciousness, they can induce other symptoms such as dizziness, nausea, trouble concentrating, memory problems and headaches. Severe concussions can cause a loss of consciousness. Most concussions resolve in days or weeks, but some patients can suffer symptoms more than a year after injury.
Pashtun Shahim, MD, of Sahlgrenska University Hospital, Sweden, and colleagues examined whether sports-related concussions were associated with elevated levels of blood biochemical markers of injury to the central nervous system. As part of the study, 288 Swedish Hockey League players underwent preseason baseline examination for concussion and some underwent preseason blood testing.
Of the 288 players followed between September 2012 and January 2013, 35 had a sports-related concussion, with 28 included in the study. Players underwent repeated blood testing in the hours and days after their injuries and when they returned to play.
Players with concussions had increased levels of the injury biomarker T-tau compared with preseason levels. The highest levels of T-tau were measured in players during the first hour after a concussion and declined during the first 12-hour period, but remained elevated six days later compared with preseason blood results. T-tau levels after concussion also were associated with the number of days it took for concussion symptoms to resolve and for players to safely return to competition.
Plasma T-tau, which is a highly CNS-specific protein, is a promising biomarker to be used both in the diagnosis of concussion and in decision-making as to when an athlete can be declared fit to return to competition, the authors concluded.