S100B levels are affected by older age but not by alcohol intoxication following mild traumatic
brain injury
Sammanfattning
Introduction
Biomarkers of brain damage and head injury are potentially useful tools in the management of
afflicted patients. Particularly S100B has received much attention and has been adapted into clinical
guidelines. Alcohol intoxication and higher age (65 years and over) have been used as risk factors
for serious complications following head injury. The effect of these factors on S100B levels has not
been fully established in a relevant patient cohort.
Methods
We prospectively included 621 adult patients with mild traumatic brain injury (TBI) and S100B
sampling. Mild TBI was defined as Glasgow Come Scale 14-15 with loss of consciousness and/or
amnesia, but without high-risk factors for intracranial complications. These patients would normally
require CT scanning according to local and most international guidelines. S100B was sampled within
3 hours following trauma.
Results
280 patients (45%) were intoxicated by alcohol. Alcohol intoxication had no effect on S100B levels (p
= 0.65) and the performance of S100B remained unchanged in these patients. 115 patients (22%)
were 65 years or older with elevated S100B levels being more common in this group compared to
patients under 65 (p = 0.029). Although the sensitivity of S100B was unchanged in older patients, the
specificity was poorer.
Conclusion
S100B can be used reliably in mild TBI patients with alcohol intoxication. The clinically utility of
S100B in older patients may be limited by very poor specificity leading to only a small decrease in
CT scanning.