Limited clinical value of multiple blood markers in the diagnosis of ischemic stroke

Objectives: No ideal blood marker exists for the diagnosis of ischemic stroke. Combined use of multiple blood markers would enhance the ability of clinical diagnosis of ischemic stroke. Design and methods: Blood concentrations of neuronal markers (NSE, VSNL-1, hFABP, and Ngb), astroglial markers (S100B and GFAP), inflammatory markers (IL-6 and TNF-alpha), blood-brain barrier marker (MMP-9), and hemostatic markers (PAI-1) were measured within 6-24 h of stroke onset. The area under the receiver operator characteristic (AUROC) curve of patients with ischemic stroke and stroke-mimic was compared after adding individual or a combination of blood markers to the clinical diagnostic assessment (age, atrial fibrillation, and Face-Arm-Speech Test [FAST]). Results: Despite acute elevations of blood IL-6, S100B, MMP-9, hFABP, and PAI-1 in univariate analysis, only IL-6, S100B, and MMP-9 were independently associated with ischemic stroke in multivariate analysis. The addition of biomarkers (IL-6, S100B, and MMP-9) did not improve the diagnostic performance of baseline clinical models with added biomarkers versus baseline clinical models alone (AUROC, 0.865 vs. 0.837, p = 0.069). Conclusions: IL-6, S100B, and MMP-9 markers are elevated in the peripheral blood during the acute phase of ischemic stroke. However, the clinical usefulness of these biomarkers is limited due to low discriminating ability when compared to clinical parameters alone in diagnosis of ischemic stroke. (c) 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.