EMBARGOED FOR RELEASE UNTIL 4 PM ET, November 07, 2018
Blood Test May Help Manage Sports-related Concussion, but Dependent on Sex, Race
MINNEAPOLIS -
A blood test that measures levels of proteins and peptides in the blood called biomarkers may help with concussion diagnosis and management, but individual differences in biomarker levels before a concussion, which vary by sex and race, may make interpreting such tests more complicated, according to a study published in the November 7, 2018, online issue of , the medical journal of the . Researchers studied seven blood biomarkers, which are proteins or peptides that have been linked to concussion. 鈥淎 blood test to aid concussion management would be a great tool for neurologists, sports physicians and other physicians since current diagnosis is more subjective, including reported symptoms, a physical exam and a review of a person鈥檚 health history,鈥 said study author James R. Clugston, MD, MS, of the University of Florida in Gainesville. 鈥淥ur study was strong in that we followed a large group of college athletes, male and female, examining biomarkers in their blood both before and after sports-related concussion.鈥 The study was divided into three parts. Part one involved 415 healthy college athletes with an average age of 19 who played football, basketball, lacrosse or soccer. None of the athletes had a recent concussion or any symptoms related to concussion, and they averaged two and a half months since they participated in contact sports. Researchers took blood samples from each athlete and measured concentrations of the seven concussion-related biomarkers. They found that female athletes had higher levels of one biomarker while male athletes had higher levels of two other biomarkers. In addition, black athletes had higher levels of one set of biomarkers while white athletes had higher levels of a different set. Clugston said, 鈥淭hese results show athletes without concussion may have differences in blood biomarkers simply due to sex and race.鈥 Part two examined blood samples from the same group of athletes to see if blood biomarker levels reflected a history of concussion prior to the start of the study. Researchers found no association between any of the biomarkers with number of previous concussions or number of years playing contact sports. Part three involved blood sampling from 29 athletes, half of them women, who had concussions while playing their sport during the study and who also contributed blood samples before their concussion. Overall, 67 percent had elevated levels of the biomarker called S100 calcium binding protein B, or S100B, on the blood test taken after a concussion when compared to their levels taken at the beginning of the study. When the researchers looked only at athletes who took the blood test within four hours of the concussion, the percentage of athletes with elevated levels of S100B rose to 88 percent. The blood tests of 36 athletes who had concussion during the study were also compared to those of 86 athletes from parts one and two who did not have concussion during the study, matched for age, race and number of concussions ever received. The researchers found differences between the concussed athlete and the non-concussed athlete samples in three of the biomarkers. When blood was tested within four hours of concussion, 88 percent of the concussed athletes had higher levels of S100B than the median level for the non-concussed athletes. A total of 75 percent of the concussed athletes had higher levels of a biomarker called total tau than the median level for the non-concussed athletes. And 81 percent of the concussed athletes had higher levels of the biomarker called beta amyloid peptide 42, or A?42, than the median level for non-concussed athletes. Part three of the study also found no relationship between any of the biomarkers and the types of symptoms the athletes were having after a concussion or how severe the concussion symptoms were. 鈥淥ur research shows that a blood test may aid concussion management, but interpreting these tests can be complicated since biomarker levels differ depending on sex and race,鈥 said author Breton Asken, MS, ATC, of the University of Florida in Gainesville. 鈥淐oncussion is complex, affecting people in different ways. Also, biomarkers may tell us what鈥檚 happening in the brain but they may not reflect a person鈥檚 actual symptoms. Much more research is needed before a blood test can advance patient care for sports-related concussion.鈥 A limitation of the study was that the concussions studied were sports-related only and did not require care in an emergency department, a setting which often includes concussions from additional sources of trauma such as motor vehicle accidents or falls. Also, biomarkers measure changes at a physiological level while a concussion diagnosis is currently based on clinical symptoms, and many factors can influence the relationship between the two. The study was supported by the Head Health Initiative, a collaboration between GE and the NFL, Banyan Biomarkers Inc. and the U.S. Army Medical Research and Material Command. The University of Florida has a financial stake in Banyan Biomarkers, which conducted the biomarker analyses. Learn more about concussion at , home of the 好色先生鈥檚 free patient and caregiver magazine focused on the intersection of neurologic disease and brain health. Follow on , and . To learn more about the AAN鈥檚 Sports Concussion Guideline and access resources, visit .