A blood test could be used to monitor NFL players’ brains—if only we would invent it

Houston Texans quarterback Tom Savage  shows a fencing response in his arms, a symptom of a concussion.
Houston Texans quarterback Tom Savage shows a fencing response in his arms, a symptom of a concussion.
Image: AP Photo/Eric Christian Smith
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Ahead of this weekend’s Super Bowl, the NFL has amended its concussion protocol—once again. This time, the change was prompted by last month’s controversial decision to let the Houston Texans quarterback return to the game minutes after convulsing on the field after a hard hit.

Identifying and treating concussions is critical, and the NFL has taken great strides to improve its concussion protocol, but we’re missing a larger piece of the conversation if we truly want to protect players.

With news breaking this month that repeated hits to the head, not just concussions, lead to chronic brain damage, we must rethink how we’re treating our athletes—in any contact sport.

The best way to protect players’ brains is with an objective, baseline blood test.

Currently, no test like this exists. In fact, the brain is the only major organ for which a standard blood test doesn’t exist.

What we need is collaboration among scientists, researchers, the NFL and other contact sports governing bodies to develop a blood test that can be used to monitor players’ brain health, as a blood test is a better alternative to CT scans and subjective tests that are entrenched in current protocol. I envision something as simple as a finger prick that would measure the concentrations of critical protein biomarkers that are known to correlate with neural damage.

Today, we have ultra-sensitive technology to detect biomarkers (or proteins) through the blood that are indicative of brain disease, but we still have not developed a standard blood test for the brain. This test would measure a combination of neural damage biomarkers that have been identified by world leading neurologists and researchers as correlating with progression of neurological damage and disease. These proteins include Tau/pTau, neurofilament light (ironically nicknamed NfL) and glial fibrillary acidic protein (GFAP).

The levels of neural damage biomarkers circulating the blood are very low—and vary from person to person—which is why a baseline test for every athlete is needed to monitor any change. The test will need to be able to measure these markers in normal samples at very low picogram per milliliter levels; rises above baseline in the 10s of picograms per milliliter levels are likely to be diagnostically relevant. 

Together, we need to collectively drive the pace of innovation, spurring adoption while disrupting today’s norms and entrenched approaches. We owe athletes, who might be our friends, sons or daughters, personalized CTE assessments. We owe it to them now—before they experience behavioral and cognitive problems.

Why haven’t we found a solution for detecting and treating CTE?

We’ve seen devastating blows to the head (most notably during the playoffs with Cam Newton and Rob Gronkowski) but counting concussions and following protocols after a concussion is only a minor step toward preventing chronic brain damage. Since repeated hits to the head can lead to CTE—a neurodegenerative brain disease—we’re missing players who might be suffering, yet haven’t experienced a concussion.  

Continuous monitoring throughout the season for all players (not just those who experience headline-making concussions) with a non-invasive blood test is the safest and easiest way to catch brain damage before symptoms present. At the beginning of each season, this baseline measurement must be taken for every player, as each individual will have a different baseline to compare their ongoing results to.

The current tests to diagnose head injuries and concussions are antiquated. The subjective tests rely on asking questions like: How many fingers am I holding up? What day of the week is it?—and put the burden of diagnosis on injured players. What we need is a scientific, objective way to show whether or not players’ brains are being damaged.

CTE is typically diagnosed only after the person is dead. The disease has only been confirmed in one living patient, former NFL player Fred McNeill, and that was through a brain scan.

CT scans are commonly used on players that shows signs of concussion or traumatic brain injury (TBI) like in the case of the first living patient diagnosed with CTE However, these tests are overused and unnecessary. Up to 90% of mild TBIs cannot be diagnosed via CT. Beyond that, these scans carry a host of concerns. Radiation emitted from CT scans is equivalent to up to 200 chest X-rays. It’s estimated that nearly 29,000 future cancer cases are linked to CT scans performed in the US in a single year.

Let me ask you: If your son or daughter was suspected of a head injury, would you rather expose them to a high dose of radiation or would you rather have their blood drawn?

With this information, we can monitor players throughout the season via blood test, and if there are any changes to a players’ blood biomarker profile, doctors and coaches will be alerted to take appropriate action.

What many of us, including the critics of contact sports, don’t know is there is still so much about how the brain works that is a mystery. How many repeated blows to the head or concussions does it take to cause irrevocable damage or lead to CTE? Do environmental or lifestyle factors play a role? Are some people more susceptible to concussions and CTE than others? These questions still puzzle researchers, and the answer for one person is rarely the same as for another.

Having an objective test that measures biomarkers in our blood that indicate disease for all players—not just those who suffer noticeable concussions—is the first step to finding a productive treatment for CTE Can we start to administer drugs say five years before we start to see symptoms? Fortunately, the digital age has opened exciting new capabilities for health surveillance and early detection of injury and disease. Companies are scrambling to develop finger prick sideline tests that can objectively inform coaches and officials of concussion severity. With blood biomarker testing, it would be near impossible for a player to miss signs of brain damage.

Personally, having grown up in the Midwest, living and breathing my Ohio State Buckeyes, I can’t imagine life without football. But it’s not just one person or one team. Only from open and collective collaboration among the right people will we create the momentum, inspiration, investment and roadmaps needed to save sports and protect the precious players who give their hearts, minds and bodies to them.

Kevin Hrusovsky is founder and chairman of Powering Precision Health and CEO of Quanterix, a biotechnology company driving the change for proactive, preventative healthcare detection and treatment.