The prognostic value of the temporal course of S100βprotein in post-acute severe brain injury: A prospective and observational study

PRIMARY OBJECTIVE: To study the predictive capacity of early S100beta samples for long-term outcome prediction after severe TBI. METHODS AND PROCEDURES: Eighty-seven patients with severe TBI were studied. Clinical and CT scan were taken at admission. S100beta concentration was quantified at admission and 24, 48 and 72 hours post-TBI (days 0, 1, 2 and 3). Outcome was assessed 12 months after discharge using Glasgow Outcome Score (GOS). RESULTS: Significant negative correlations were found between 1-year GOS and S100beta concentrations on days 1-3, but not on day 0. Deceased patients showed higher S100beta concentration than survivors on days 1-3. Good (GOS = 4-5) vs poor outcome (GOS = 1-3) differed significantly on day 3. Death outcome was independently predicted by day 2 (>2.37 microg l(-1)), day 3 (>1.41 microg l(-1)) samples and absence of pupillary reaction. Poor outcome was predicted independently only by pupillary reaction and the 72-hour sample (>1.1 microg l(-1)), but this predictive model was less satisfactory than the predictive model for death. CONCLUSIONS: A temporal profile of S100beta release from admission to 72 hours post-TBI is strongly recommended for use in identifying patients at risk of developing a worse outcome. The S100beta protein might be an early biomarker for predicting long-term outcome in patients with acute severe TBI.