Blood test detects concussion and subconcussive injuries in children and adults

Traumatic brain injury with no symptoms can cause wear and tear over time

August 26, 2019

Science Daily/Orlando Health

In one of the largest studies of its kind, researchers at Orlando Health are making new progress in finding ways to detect a traumatic yet sinister brain injury -- and getting closer to preventing further damage.

Subconcussive injuries often show no symptoms or immediate effects, but can cause wear and tear on the brain over time with repeated injuries. The latest study, published in the journal BMJ Paediatrics Open, includes more than 700 emergency room patients -- children and adults. The study gets us closer to developing a standard blood test to spot these injuries as early as possible.

"A unique feature of this study is that it includes patients who hit their heads but have no symptoms," said Linda Papa, MD, lead author of the study and emergency medicine doctor at Orlando Health. "This group is rarely -- if ever -- included in biomarker studies."

The blood test looks for two proteins (GFAP and UCH-L1) found in our brains and released into blood after an injury -- higher levels of which could indicate a concussion or subconcussive injury. Dr. Papa has been studying these biomarkers for more than a decade. Some of her previous studies have focused on athletes, but now she's expanding her research on subconcussive injuries to the general population and all age groups.

Historically, people who suffer head trauma without concussion symptoms may have been classified as having "no injury." Plus, there are very few studies addressing the impact of subconcussive injuries following head trauma in the civilian population, as opposed to military members or athletes.

"It is estimated that up to 3.8 million concussions occur in the U.S. annually from organized and recreational sports -- and there are more than 2 million ER visits for traumatic brain injuries and concussions," said Papa. "It is a significant health problem in both athletes and non-athletes."

The study looked at patients with concussions, those with head trauma without overt signs of concussion and those with body trauma without head trauma or concussion. Elevated levels of both biomarkers were found in patients with nonconcussive head trauma, potentially signaling a subconcussive brain injury.

Furthermore, this blood test goes even deeper than a routine CT scan. Previous studies using the two biomarkers have focused on detecting brain lesions, but subconcussive injuries don't necessarily result in lesions -- and even the vast majority of patients with concussions tend to have a normal CT scan.

"The study includes an array of patients with different injury mechanisms, including car crashes, falls and bicycle accidents in addition to recreational and sports injuries," said Papa. "It is not limited to just one group of injury types."

A number of companies are now working on developing a bench-top device for the hospital lab -- along with a point-of-care handheld device that can be used to detect subconcussive injuries in a variety of settings -- including sporting events, in the ambulance, at the scene of car crashes, in military settings or even after a simple bump to the head.

"The technology is only a year or two away," said Papa.

https://www.sciencedaily.com/releases/2019/08/190826092315.htm

After concussion, biomarkers in the blood may help predict recovery time

July 3, 2019

Science Daily/American Academy of Neurology

A study of high school and college football players suggests that biomarkers in the blood may have potential use in identifying which players are more likely to need a longer recovery time after concussion, according to a study published in the July 3, 2019, online issue of Neurology®, the medical journal of the American Academy of Neurology.

"With so many people sustaining concussions and a sizeable number of them having prolonged symptoms and recovery, any tools we can develop to help determine who would be at greater risk of problems would be very beneficial, so these results are a crucial first step," said study author Timothy B. Meier, PhD, of the Medical College of Wisconsin in Milwaukee and a member of the American Academy of Neurology.

The study involved 41 high school and college football players who experienced a concussion during the season. None of the players lost consciousness with their concussions. The players were matched with 43 football players of the same level, age and position who did not have a concussion during that season.

All of the participants had blood tests at the beginning of the season. Those who had concussions had blood tests within six hours after the injury, then again 24 to 48 hours later and also eight, 15 and 45 days later. Those who did not have concussions had tests at similar times for comparison.

The tests looked at levels of seven biomarkers for inflammation that have been related to more severe brain injury. Of the seven biomarkers, two were elevated for those with concussion at six hours after the injury compared to the athletes with no concussion. The biomarkers interleukin 6 and interleukin 1 receptor antagonist were both elevated at six hours after concussion.

For interleukin 6, levels at the beginning of the study were 0.44 picograms per milliliter (pg/mL) for those who later had concussions and 0.40 pg/mL for those who did not have concussions. At six hours after the injury, those with concussions had levels of 1.01 pg/mL, compared to levels of 0.39 at a similar time for those without concussions.

"These results demonstrate a meaningful increase in the levels of interleukin 6 for athletes who sustained a concussion compared to athletes who did not," said Meier.

Athletes with higher levels of interleukin 6 six hours after the injury were also more likely to take longer to recover from their symptoms. Overall, the athletes with concussions had symptoms for an average of 8.9 days. Eight of the 17 athletes with concussion and high interleukin 6 levels at six hours after injury, compared to their levels at the beginning of the season, still had concussion symptoms eight days after the injury.

"Eventually, these results may help us better understand the relationship between injury and inflammation and potentially lead to new treatments," Meier said.

https://www.sciencedaily.com/releases/2019/07/190703171853.htm