plasma tau relates to prolonged return to play after concussion

J, Merchant-Borna K, Jeromin A, Livingston W, Bazarian J. Neurology.
2017; 88:1-8.

Take Home Message:
Elevated plasma tau concentrations within 6 hours of sport-related concussion
was associated with prolonged return to play.

clinical tools used to diagnose and return concussed athletes to play rely on patient-reported
information. An objective predictor, such as a blood test for
tau protein, would provide an unbiased tool to
determine an athlete’s diagnosis, prognosis and readiness for return to play. Therefore,
the authors evaluated NCAA Division I and III contact-sport athletes between
2009-2014 to determine changes in tau following concussion compared to
preseason. The authors also compared tau changes after a sports-related
concussion (43 athletes) to both an athletic control group (no concussion; 37
athletes) and a healthy, nonathletic, control group (21 participants). All
athletes gave blood samples during pre-season. Athletes that sustained a
sports-related concussion also gave blood samples within 6 hours of injury, and
then 2, 3, and 7 days post injury. Athletes that sustained concussions were
then grouped into long return to play (> 10 days) or short return to play (<
10 days). Healthy athletes had blood draws at the same time points as the
concussion group, and nonathletic participants had blood draws at an unrelated
time point. Thirty-nine percent of the athletes with concussion returned in
less than 10 days. Females were nearly 6 times more likely to be in the
prolonged return to play group (61%).  Both
healthy and concussed athletes had higher mean tau during pre-season and all
other times compared to nonathletic participants. The healthy athletes had
higher mean tau concentrations compared to the concussed athletes at 24 and 72
hours. Athletes with long return to play had higher mean tau at 6 hours, 24
hours, and 72 hours post injury, after controlling for sex, compared to those
with short return to play. The authors found that higher plasma tau 6 hours
post-concussion was a good predictor of return to play in less than 10 days.

authors presented that changes in tau from pre-season to 6 hours after a
concussion was an accurate predictor of prolonged return to play following a
concussion. Identifying biomarkers to better understand how an athlete may
recover may protect athletes from neuronal damage, subsequent concussions, and
sustaining further injuries (lower extremity injuries). Concussed athletes that
took longer to recover typically had higher tau concentrations compared to
those that took less than 10 days to recover. Therefore, the authors suggest
that tau could be used as a prognostic biomarker. However, the mean tau levels at
24 and 72 hours were lower in the concussed athletes compared to the healthy
athletes, which may suggest that physical activity can increase mean tau. This
is supported by the finding that all athletes had higher levels of tau during
pre-season compared with nonathletic participants. More research will need to
be done to replicate and validate these findings in larger cohorts, while
controlling for physical exertion. Currently, medical professionals should
continue to use multiple clinical tests for concussion diagnosis and safe
progression of athletes to play, and continue to be on the lookout for a
reliable objective predictor such as a blood biomarker to use in his/her
concussion protocol.

Questions for
Discussion: Are biomarkers something you would be interested in implementing
into your concussion protocol in the future? If not, what are your

Written by: Jane McDevitt, PhD
by: Jeff Driban

Related Posts:

Gill, J., Merchant-Borna, K., Jeromin, A., Livingston, W., & Bazarian, J. (2017). Acute plasma tau relates to prolonged return to play after concussion Neurology, 88 (6), 595-602 DOI: 10.1212/WNL.0000000000003587