Blood Test Predicts Prognosis For Traumatic Brain Injuries

Blood Test Predicts Prognosis For Traumatic Brain Injuries
A new blood test could help emergency room doctors quickly diagnose traumatic brain injury and determine its severity. The findings, published in the Journal of Neurotrauma, could help identify patients who might benefit from extra therapy or experimental treatments.

After a hit to the head or rapid whiplash, whether from a car crash, athletic event or other accident, millions of people develop traumatic brain injuries (TBIs) each year. TBIs can range from mild concussions - causing only a headache or temporary blurred vision - to much more severe injuries - causing seizures, confusion, memory and attention problems, muscle weakness, or coma for many months. These symptoms, whether mild or more severe, are generally caused by damaged brain cells.
Until now, most physicians have relied on CT scans and patients' symptoms to determine whether to send them home and have them resume their usual activities or take extra precautions. However, CT scans can only detect bleeding in the brain, not damage to brain cells, which can happen without bleeding.
The researchers wanted to know if a blood test could better predict which patients would have ongoing brain injury-related problems, to provide better treatment for them. So they measured the levels of three proteins that they suspected play a role in brain cell activity in more than 300 patients with a TBI and 150 patients without brain injuries. Then, they followed those with a TBI for the next six months.
Levels of one protein, called brain-derived neurotrophic factor (BDNF), taken within 24 hours of someone's head injury, could predict the severity of a TBI and how a patient would fare, they found. While healthy people averaged 60 nanograms per milliliter of BDNF in their bloodstreams, patients with brain injuries had less than one-third of that amount, averaging less than 20 nanograms per milliliter, and those with the most severe TBIs had even lower levels, around 4 nanograms per milliliter. Moreover, patients with high levels of BDNF had mostly recovered from their injuries six months later. But in patients with the lowest levels of BDNF, symptoms still lingered at follow-up. The results suggest that a test for BDNF levels, administered in the emergency room, could help stratify patients.
The researchers want to follow up with more research on why, at a molecular level, brain injuries lower levels of BDNF in the blood and whether things known to increase BDNF levels - including exercise and omega-3 fatty acids - could help treat TBIs. They also wants to know whether changes in BDNF levels over time can be a proxy for recovery and if they could be used to gauge the effectiveness of an intervention.
Based on material originally posted by Johns Hopkins Medicine.