Concussion has become an increasingly large public health issue, notably in the context of sports injuries, but accurately diagnosing the condition and how long it will last has generally relied on patient surveys.
This method, however, is not necessarily the most accurate way of gauging the severity of a concussion, and better markers have been sought. This week, writing in JAMA Pediatrics journal, researchers from Penn State College of Medicine have found a new marker in an unusual place: a patient’s spit.
Specifically, the researchers measured the levels of microRNAs, which are small scraps of noncoding RNA, in the saliva of concussion patients and found that certain microRNAs were better at identifying concussions than patient surveys. They found that these markers could also better predict the length of concussion symptoms.
Steven Hicks, M.D.,Ph.D., an assistant professor of pediatrics, said, “There's been a big push recently to find more objective markers that a concussion has occurred, instead of relying simply on patient surveys.”
“Previous research has focused on proteins, but this approach is limited because proteins have a hard time crossing the blood-brain barrier. What’s novel about this study is we looked at microRNAs instead of proteins, and we decided to look in saliva rather than blood.”
Finding a more accurate diagnosis of the condition and its severity is important, as treatment is typically centered around rest and abstention from anything, such as sports, that could agitate the condition. But if a doctor uses a patient survey and doesn’t give a patient enough time to recover, they could be putting them at risk of suffering further damage.
The more times a person has a concussion, the risk increases that it could lead to further damage. Some recent studies suggest that even mild concussion could increase the risk of late-life cognitive impairment as well as neurodegenerative disease, especially when repeated injuries are involved.
The JAMA study looked at around 50 younger patients (all under 21), using the survey approach via the Sport Concussion Assessment Tool (SCAT-3) and the saliva test.
Hicks says, “The microRNAs were able to predict whether symptoms would last beyond four weeks with about 85% accuracy.”
“In comparison, using the SCAT-3 report of symptoms alone is about 64% accurate. If you just go off the parent's report of symptoms, it goes down to the mid-50s. In this pilot study, these molecular signatures are outperforming survey tools.”