Predictors of Stroke Events in Patients with Transient Ischemic Attack Attributable to Intracranial Stenotic Lesions

OBJECTIVE: The purpose of this study was to identify the predictors of subsequent ischemic stroke events in patients with transient ischemic attack (TIA) attributable to intracranial arterial occlusive lesions. METHODS: The study population included 82 patients (55 men; mean age, 69.3±12.1 years) with TIA caused by intracranial arterial occlusive lesions who were admitted to our stroke care unit within 48 h of the onset of a TIA between April 2008 and November 2015. TIA was diagnosed if focal neurological symptoms ascribable to a vascular etiology lasted less than 24 h, irrespective of the presence of ischemic insults on imaging. The primary endpoint was an ischemic stroke event within 90 days of the onset of a TIA. RESULTS: The 90-day risk of ischemic stroke after the onset of a TIA was 14.6% [95% confidence interval (CI): 8.6-23.9%]. Cox proportional hazards multivariate analyses revealed that diffusion-weighted imaging (DWI) positivity [hazard ratio (HR), 8.73; 95%CI, 2.20-41.59; p=0.002], prior ischemic stroke (HR, 4.03; 95%CI, 1.07-15.99; p=0.040), and a high serum level of alkaline phosphatase (ALP) on admission (HR, 1.15; 95%CI, 1.05-1.26; p=0.002, for every +10 U/L) were significant independent predictors of ischemic stroke within 90 days after the onset of a TIA. CONCLUSION: Our results suggested that patients with a TIA attributable to intracranial artery disease who showed DWI lesions, prior ischemic stroke, or high serum levels of ALP on admission were at high risk of subsequent ischemic stroke events.