Diagnostic performance of Glial Fibrillary Acidic Protein and Prehospital Stroke Scale for identifcation of stroke and stroke subtypes in an unselected patient cohort with symptom onset < 4.5 h

Abstract

Introduction Rapid identifcation and treatment of stroke is crucial for the outcome of the patient. We aimed to determine the performance of glial fbrillary acidic protein (GFAP) independently and in combination with the Prehospital Stroke Score (PreSS) for identifcation and diferentiation of acute stroke within 4.5 h after symptom onset. Patients and methods Clinical data and serum samples were collected from the Treat-Norwegian Acute Stroke Prehospital Project (Treat-NASPP). Patients with suspected stroke and symptoms lasting≤4.5 h had blood samples collected and were evaluated with the National Institutes of Health Stroke Scale prospectively. In this sub study, NIHSS was retrospectively translated into PreSS and GFAP was measured using the sensitive single molecule array (SIMOA). Results A total of 299 patients with suspected stroke were recruited from Treat-NASPP and included in this study (44% acute ischemic stroke (AIS), 10% intracranial hemorrhage (ICrH), 7% transient ischemic attack (TIA), and 38% stroke mimics). ICrH was identifed with a cross-fold validated area under the receiver-operating characteristic curve (AUC) of 0.73 (95% CI 0.62–0.84). A decision tree with PreSS and GFAP combined, frst identifed patients with a low probability of stroke. Subsequently, GFAP detected patients with ICrH with a 25.0% sensitivity (95% CI 11.5–43.4) and 100.0% specifcity (95% CI 98.6–100.0). Lastly, patients with large-vessel occlusion (LVO) were detected with a 55.6% sensitivity (95% CI 35.3–74.5) and 82.4% specifcity (95% CI 77.3–86.7). Conclusion In unselected patients with suspected stroke, GFAP alone identifed ICrH. Combined in a decision tree, GFAP and PreSS identifed subgroups with high proportions of stroke mimics, ICrH, LVO, and AIS (non-LVO strokes). Keywords Stroke, Diagnosis, GFAP, PreSS, Prehospital