Serum S100B and Its Interplay With hs-CRP and Platelet Count in Association With Adverse Outcomes After Ischemic Stroke.

BACKGROUND: S100B (serum S100 calcium-binding protein B) has been linked to blood-brain barrier disruption and neuroinflammation, but its prognostic value for ischemic stroke remains controversial. We aimed to examine baseline serum S100B and its interplay with high-sensitivity C-reactive protein and platelet count in association with clinical outcomes after ischemic stroke. METHODS: Data were derived from a prospective multicenter cohort involving 3249 patients with acute ischemic stroke in 26 hospitals across China. Serum S100B concentrations were measured at baseline, and patients were followed up for 3 months after ischemic stroke. Study outcomes included death, major disability, and vascular events. Multivariable-adjusted Cox proportional hazards regression models and logistic regression models were applied to estimate hazard ratios (HRs) or odds ratios (ORs) and their 95%CIs. RESULTS: During the 3-month follow-up, 92 (2.8%) patients died. Higher baseline serum S100B levels were associated with an increased risk of death (quartile 4 versus quartile 1: adjusted HR, 2.09 [95% CI, 1.09-4.02]; Ptrend=0.028). Each SD increase in log-transformed serum S100B was associated with a 38% greater risk of death. A spline regression model showed a linear relationship between serum S100B and death risk (Plinearity=0.006). Significant joint effects were observed between S100B and high-sensitivity C-reactive protein, and between S100B and platelet count, in association with death after ischemic stroke. The highest risk was observed among patients with elevations in all 3 biomarkers. CONCLUSIONS: Elevated serum S100B levels in the acute phase of ischemic stroke were independently associated with increased mortality risk. A single combined measure of S100B, high-sensitivity C-reactive protein, and platelet count may further improve risk stratification. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT01840072.