NEW YORK – A new study led by researchers at the University of California at San Francisco has found that two protein biomarkers can help predict whether patients with traumatic brain injury will suffer severe disability or death from their injuries.
The researchers studied the value of testing patients with TBI, more commonly called concussions, for the glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCH-L1) markers using Abbott Laboratories' point-of-care i-STAT Alinity System.
In total, close to 1,700 patients were tested with the assay, and then assessed six months after their injuries using the Glasgow Outcome Scale Extended, which is used to evaluate patients with TBI for disability. They found that the test was able to predict those patients who were most likely to die from their injuries or experience severe disability six months after suffering their injury. The findings were published on Wednesday in The Lancet Neurology.
Investigators from the University of Pennsylvania and the University of Michigan also contributed to the study, which was carried out via Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI), an observational cohort study led by UCSF involving patients from 18 US level 1 trauma centers. The US National Institutes of Health launched TRACK-TBI in 2014, and TRACK-TBI began evaluating Abbott's test three years ago, the same year that Abbott obtained a nonexclusive license to the markers from Banyan Biomarkers. Banyan gained US Food and Drug Administration authorization for a test based on the markers in 2018.
As part of its evaluation, the researchers found that elevated levels of the GFAP marker were able to predict who would die or suffer severe injury in 87 percent and 86 percent of cases, respectively, while elevated levels of the UCH-L1 marker predicted mortality and severe injury at six months in 89 percent and 86 percent, respectively. The markers were less effective — roughly in 60 percent of cases — at distinguishing incomplete and complete recovery though.
By factoring in other variables, including age, motor score, pupil reactivity, and CT scan findings, they could improve the accuracy of their predictions to 94 percent in the case of mortality and 89 percent in the case of severe disability. In patients with mild traumatic brain injury, the ability to predict complete versus incomplete recovery was less, at 69 percent.
Based on the findings, the authors suggested Abbott's point-of-care test could be used to triage patients with traumatic brain injury for more aggressive treatment. They also said that the results could be used to help families make decisions in situations where the patient has suffered a catastrophic injury.
Following the publication of the new study, the NIH issued a statement saying the measurement of the GFAP and UCH-L1 markers "may enable a more accurate assessment of patient prognosis following TBI." The NIH noted that GFAP and UCH-L1 are currently used to diagnose traumatic brain injury, but said that the study suggests that the markers could also be used to predict recovery as well as to improve the accuracy of conventional assessment models.
"Although additional studies are necessary to reproduce the results, the findings indicate that blood-based biomarkers may help clinicians and researchers better predict patient outcomes after TBI," the NIH said.
Frederick Korley, the first author on the study and an associate professor of emergency medicine at the University of Michigan, said via email that the TRACK-TBI is now planning a clinical trial to study the efficacy of new therapies to treat traumatic brain injury patients. As part of the trial, the investigators will use the GFAP and UCH-L1 markers to select patients for the trial.
"We will also use these biomarkers to monitor individual patient response to these promising therapeutics," Korley said.