Serum S100β as a prognostic marker in patients with non-traumatic intracranial hemorrhage.

Background: The serum concentration of S100β protein reportedly predicts outcomes after brain injury. We examined the prognostic accuracy of S100β in patients with non-traumatic intracranial hemorrhage.
Methods: This was a prospective, observational study of patients with non-traumatic intracranial hemorrhage treated in the intensive care unit at our university hospital. Computed tomography imaging findings and the level of consciousness on admission were recorded. Serum S100β concentration was measured serially during the first six days of admission. Patients with subarachnoid hemorrhage (SAH group) or intracerebral hemorrhage (ICH group) were analyzed separately. The 3-month and 1-year functional outcomes were assessed using the Glasgow Outcome Scale (GOS).
Results: Of 108 patients enrolled, 66 were included in the SAH group and 42 in the ICH group. High initial S100β concentration was associated with Glasgow Coma Score 3-6 on admission (SAH group 0.61 μg/L versus 0.15 μg/L, P=0.001 and ICH group 1.00 μg/L versus 0.42 μg/L, P=0.005). Initial S100β concentration correlated with ICH volume (rho=0.50, P<0.001) and IVH Sum Score (rho=0.30, P=0.013). The thresholds for the initial S100β concentration with 100% specificity for poor outcome (GOS 1-3) were 1.40 μg/L for SAH and 1.76 μg/L for ICH group. ORs varied between 3.1 and 6.1 for S100β on poor outcome in the SAH group. Increasing S100β level during study period was associated with poor outcome in the SAH group.
Conclusions: Serum S100β concentration corresponds with the severity of neurological insult and predicts poor outcome in patients with non-traumatic intracranial hemorrhage.