, according to a new study of collegiate athletes and recovery time. “Although preliminary, the current results highlight the potential role of biomarkers in tracking neuronal recovery, which may be associated with duration of [return to sport],” wrote Cassandra L. Pattinson, PhD, of the University of Queensland, Brisbane, Australia, and the National Institutes of Health, Bethesda, Md., along with coauthors. The study was published in JAMA Network Open.
To determine if three specific blood biomarkers – total tau protein, glial fibrillary acidic protein (GFAP), and neurofilament light chain protein (NfL) – can help predict when athletes should return from sports-related concussions, a multicenter, prospective diagnostic study was launched and led by the Advanced Research Core (ARC) of the Concussion Assessment, Research, and Education (CARE) Consortium. The consortium is a joint effort of the National Collegiate Athletics Association (NCAA) and the U.S. Department of Defense.
From among the CARE ARC database, researchers evaluated 127 eligible student athletes who had experienced a sports-related concussion, underwent clinical testing and blood collection before and after their injuries, and returned to their sports. Their average age was 18.9 years old, 76% were men, and 65% were White. Biomarker levels were measured from nonfasting blood samples via ultrasensitive single molecule array technology. As current NCAA guidelines indicate that most athletes will be asymptomatic roughly 2 weeks after a concussion, the study used 14 days as a cutoff period.
Among the 127 athletes, the median return-to-sport time was 14 days; 65 returned to their sports in less than 14 days while 62 returned to their sports in 14 days or more. According to the study’s linear mixed models, athletes with a return-to-sport time of 14 days or longer had significantly higher total tau levels at 24-48 hours post injury (mean difference –0.51 pg/mL, 95% confidence interval, –0.88 to –0.14; P = .008) and when symptoms had resolved (mean difference –0.71 pg/mL, 95% CI, –1.09 to –0.34; P < .001) compared with athletes with a return-to-sport time of less than 14 days. Athletes who returned in 14 days or more also had comparatively lower levels of GFAP postinjury than did those who returned in under 14 days (4.39 pg/mL versus 4.72 pg/mL; P = .04).
Preliminary steps toward an appropriate point-of-care test
“This particular study is one of several emerging studies on what these biomarkers look like,” Brian W. Hainline, MD, chief medical officer of the NCAA, said in an interview. “It’s all still very preliminary – you couldn’t make policy changes based on what we have – but the data is accumulating. Ultimately, we should be able to perform a multivariate analysis of all the different objective biomarkers, looking at repetitive head impact exposure, looking at imaging, looking at these blood-based biomarkers. Then you can say, ‘OK, what can we do? Can we actually predict recovery, who is likely or less likely to do well?’ ”
“It’s not realistic to be taking blood samples all the time,” said Dr. Hainline, who was not involved in the study. “Another goal, once we know which biomarkers are valuable, is to convert to a point-of-care test. You get a finger prick or even a salivary test and we get the result immediately; that’s the direction that all of this is heading. But first, we have to lay out the groundwork. We envision a day, in the not too distant future, where we can get this information much more quickly.”
The authors acknowledged their study’s limitations, including an inability to standardize the time of biomarker collection and the fact that they analyzed a “relatively small number of athletes” who met their specific criteria. That said, they emphasized that their work is based on “the largest prospective sample of sports-related concussions in athletes to date” and that they “anticipate that we will be able to continue to gather a more representative sample” in the future to better generalize to the larger collegiate community.
The study was supported by the Grand Alliance Concussion Assessment, Research, and Education Consortium, which was funded in part by the NCAA and the Department of Defense. The authors disclosed receiving grants and travel reimbursements from – or working as advisers or consultants for – various organizations, college programs, and sports leagues.
SOURCE: Pattinson CL, et al. JAMA Netw Open. 2020 Aug 27. doi: 10.1001/jamanetworkopen.2020.13191.