Stroke Risk in Patients with Suspected Transient Ischemic Attacks with Focal and Nonfocal Symptoms: A Prospective Study

Abstract

ObjectivesThe aim was to investigate triage methods for suspected transient ischemic attacks (TIAs) with focal or nonfocal symptoms. Materials and methodsIn total, 350 patients with suspected TIAs were enrolled and followed for one year. Potential high-risk factors for TIAs, such as atrial fibrillation, carotid artery stenosis, crescendo TIA, and ABCD2 score ≥ 4, were evaluated. Patients were classified into 3 groups according to the initial neurological symptoms: focal, nonfocal, and mixed (both focal and nonfocal) groups. Stroke-free survival rates were compared via Kaplan-Meier analysis. ResultsDiffusion-weighted MRI (DWI) was performed for 89.8% of the patients within 7 days, and the frequency of acute brain infarction on DWI was significantly lower in the nonfocal group (focal, 24.1%; nonfocal, 7.2%; mixed, 22.2%; P < .01). There was no significant difference in the one-year event-free survival rates across the groups.Significantly higher stroke risk was observed in patients with one or more high-risk categories or the ABCD2 score (≥ 4) in the focal group (P = .021 and .26, respectively), whereas no significant difference was observed in the other groups. Across all symptom groups, significantly higher stroke risk was observed in patients showing acute infarcts on DWI evaluated within 7 days. ConclusionsBoth high-risk categorization (≥ 1 potential high-risk factors) and ABCD2 score (≥ 4) alone were useful tools for identifying higher stroke risk in patients with focal symptom but not with nonfocal symptoms in isolation. Further studies are warranted in triage methods for TIA with nonfocal in isolation in conjunction with DWI.