Jonathan Silver, MD

Tau levels were correlated with concussion in the first 6 days in a group of hockey players.

Because concussion is currently diagnosed by clinical symptoms and self-report, researchers have sought “objective” markers of neuronal injury. In addition to findings from advanced imaging techniques, several biomarkers of glial and neuronal injury have been explored. These investigators prospectively studied changes in several biomarkers in blood — total tau (T-tau; a marker of axonal damage), S-100 calcium binding protein B (S-100B; a glial marker), and neuron-specific enolase (NSE; a marker of neuronal injury). Two authors are industry employees; two others have a related patent application.

Of 188 Swedish hockey players who participated, 35 sustained a concussion, and 28 had post-concussion blood samplings at 1, 12, 36, and 144 hours afterwards. Postconcussion levels were compared with preseason assessments in a subset of 47 players.

S-100B and NSE were found not to be reliable markers of injury, as levels increased after a “friendly game” when no concussion occurred. T-tau levels were significantly higher in postconcussion samples at all times, but were highest during the first hour, with a trend toward a second peak 36 hours postconcussion. The concentration of 1-hour postconcussion T-tau correlated with the number of days needed for symptoms to resolve. Significantly elevated T-tau levels at 144 hours were associated with symptoms that lasted more than 6 days.

Citation(s):

Shahim P et al. Blood biomarkers for brain injury in concussed professional ice hockey players. JAMA Neurol 2014 Mar 13; [e-pub ahead of print].

Gatson J and Diaz-Arrastia R. Tau as a biomarker of concussion. JAMA Neurol 2014 Mar 13; [e-pub ahead of print].