Etiology, Duration, and Prognosis of Transient Ischemic Attacks

Abstract

Context: A transient ischemic attack (TIA) has been arbitrarily defined as a focal cerebral ischemic deficit lasting less than 24 hours. Objective: To determine if TIAs of short duration (?1 hour) and long duration (1 hour to ?24 hours) differ from each other and from ischemic stroke (IS). Design, Setting, and Patients: Inception cohorts of 1429 patients with acute TIAs and 5206 patients with IS were prospectively documented in 15 German medical centers with neurology departments and acute stroke units. Outcome after 3 months was assessed in 72.8% of the patients with TIAs. Results: Patients with TIAs, especially those with symptoms lasting less than 1 hour, were significantly more likely to have a history of TIAs and less likely to have diabetes mellitus, arterial hypertension, or atrial fibrillation at admission compared with those with IS. Cardioembolic etiologies were less frequent and un- known etiologies more frequent among patients with TIAs than those with IS. Functional outcome and mor- tality did not differ significantly in patients with TIAs of different durations. Conclusion: This study demonstrates differences in comorbidity and etiology among patients with TIAs of different durations and IS. Main Outcome Measures: Risk factor distribution, etiology, and prognosis of TIAs and IS. Arch Neurol. 2002;59:1584-1588