Stroke is one of the leading causes of disability worldwide. Early prediction of post-stroke disability using clinical models is of great interest, especially in the rehabilitation field. Although some biomarkers and neuroimaging techniques have shown potential predictive value, there are still insufficient data to support their clinical utility in predicting post-stroke functional recovery.

To assess the value of serum biomarkers (CRP, d-Dimer, fibrinogen, and S100β protein), in predicting medium to long-term (12 weeks) functional outcome, in patients with acute ischemic stroke.

This is an observational, prospective study in a sample of patients hospitalised for ischemic stroke (n=131). Peripheral blood levels of biomarkers of interest were determined at admission (C-reactive protein, D-dimer, and fibrinogen) or at 48hours post-stroke (S100β protein). Functional status was accessed at 48hours and 12 weeks post-stroke, using the modified Rankin Scale (mRS).

S100β protein levels measured at 48hours were significantly associated with mRS at 12 weeks (OR=1.005, 95% CI [1.005–1.007]; P<0.001). This association that was not seen for the remaining biomarkers of interest. The S100β cut-off for poor functionality at 12 weeks was≥140.5ng/L (sensibility 83.8%; specificity 71.4%; AUC=0.80, 95% CI [0.722, 0.879]).

S100β levels in peripheral blood at 48hours post-stroke reflect acute stroke severity and predict functional outcome at 12 weeks with a cut-off value of 140.5ng/dL. The value of S100β as predictor of functional recovery after-stroke should be emphasised in further clinical research and clinical practice.