Biomarkers in the blood may help predict which athletes need a longer recovery time after concussion, new research suggests.
The US study involved 41 high school and college American football players who experienced a concussion during the season. The players were matched with 43 others 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 of sustaining the injury, then again 24 to 48 hours later and also eight, 15 and 45 days later. Those who did not have concussions had a similar series of tests 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 (interleukin 6 and interleukin 1 receptor antagonist) were elevated for those with concussion at six hours after the injury compared to the athletes with no concussion.
Further analysis showed that athletes with higher levels of interleukin 6 six hours after the injury were 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.
"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.
"Eventually, these results may help us better understand the relationship between injury and inflammation and potentially lead to new treatments," Meier added.
The findings have been published in the online issue of Neurology, the medical journal of the American Academy of Neurology.