Using Saliva to Better Understand Concussions


By Hamilton Waldron

When it comes to properly diagnosing a concussion, it’s often difficult to get a definitive answer. However, a recent Penn State University study suggests that small molecules in saliva may help facilitate a quicker, more accurate diagnosis of concussions in children.

What Exactly Is a Concussion?

A concussion is a type of brain injury caused by a blow, bump or jolt to the head. A violent hit to the body can also cause a concussion as a result of the force of the blow moving the head and brain back and forth rapidly.

While concussions are not life threatening, they’re still a very serious injury that causes myriad symptoms, including headache, nausea, vomiting, dizziness, coordination problems, blurry vision, sluggishness, confusion, and memory problems.

The Proof Is in the Saliva

During this study, researchers discovered that a select number of small molecules in saliva are loaded with pertinent information for diagnosing concussions and determining their severity and duration.

These molecules are known as microRNAs and are appreciably altered following a significant brain injury. Researchers were in search of an objective test that would help identify concussions, so they were eager to see if it was possible to create one from analyzing the type of microRNAs found in a patient’s spit.

Simple Testing Method Yields Unexpected Results

Roughly two-thirds of concussions occur in children and adolescents, so the study involved 53 participants between the ages of 7 and 21 who had suffered a concussion. The study was executed by asking participants to spit in a cup. The samples were then analyzed, measuring the levels of a variety of microRNAs.

The results impressed researchers because the presence of five microRNAs identified patients who would have prolonged symptoms with an accuracy rate of about 85 percent.

Where Do We Go From Here?

Athletes returning to action prematurely after a concussion can be very dangerous. Often times, a young athlete might even try to lie about lingering symptoms so they can return to competition.

"It's frustrating for both parents and physicians that we can't accurately and objectively predict how long a child's concussion symptoms might last, what those symptoms are likely to consist of and when it might be safe for them to return to sports or school,” said lead author of the study Steve Hicks, MD, PhD.

Although more research is needed, these findings could one day help to improve the diagnosis and care of concussion patients. 

Discussion Questions

  • Brainstorm some other ways that saliva could be used to aid in the prevention and diagnosis of illness and injury.
  • Why is it important to be able to diagnose a concussion in patients who aren't showing symptoms?


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