Use of biomarkers in triage of patients with suspected stroke

The absence of a rapidly available and sensitive diagnostic test represents an important limitation in the triage of patients with suspected stroke.

The aim of the present study was to investigate the triage accuracy of a novel test that measures blood-borne biomarkers (triage stroke panel, TSP) and to compare its accuracy with that of the Cincinnati Prehospital Stroke Scale (CPSS).

Consecutive patients with suspected stroke presenting to the Emergency Departments of three Italian hospitals underwent triage by a trained nurse according to the CPSS and had blood drawn for TSP testing. The TSP simultaneously measures four markers (B-type natriuretic peptide, D-dimer, matrix metalloproteinase-9, and S100β) presenting a single composite result, the Multimarker Index (MMX). Stroke diagnosis was established by an expert committee blinded to MMX and CPSS results.

There were 155 patients enrolled, 87 (56%) of whom had a final diagnosis of stroke. The area under the receiver operating characteristic (ROC) curve for CPSS was 0.77 (95% confidence interval [CI] 0.70-0.84) and that of MMX was 0.74 (95% CI 0.66-0.82) (p = 0.285). Thus, both tests, when used alone, failed to recognize approximately 25% of strokes. The area under the ROC curve of the combination of the two tests (0.86, 95% CI 0.79-0.91) was significantly greater than that of either single test (p = 0.01 vs. CPSS and p < 0.001 vs. TSP).

In an emergency care setting, a panel test using multiple biochemical markers showed triage accuracy similar to that of CPSS. Further studies are needed before biomarkers can be introduced in the clinical work-up of patients with suspected stroke.