Short-term prognosis after emergency department diagnosis of TIA

Objective—To determine the short-term risk of stroke and other adverse events after emergency department diagnosis of transient ischaemic attack (TIA).

Methods—A 12 month prospective cohort study was performed with patients identified from 16 hospitals in northern California. Patients were followed up for 90 days—the primary outcome measure was stroke during this period. Other events (death, recurrent TIA and other cardiovascular events) were also noted.

Results—Of 1707 patients with TIA, 180 suffered a stroke, 50% of these occurring within the first two days. Five factors were independently associated with stroke: age more than 60 years (odds ratio 1.8; 95% CI 1.1, 2.7), diabetes mellitus (odds ratio 2.0; 95% CI 1.4, 2.9), symptom duration more than 10 minutes (odds ratio 2.3; 95% CI 1.3, 4.2), weakness (odds ratio 1.9; 95% CI 1.4, 2.6) and speech impairment (odds ratio 1.5; 95% CI 1.1, 2.1). Stroke or other adverse event occurred in 25.1%, including 44 admissions for cardiovascular events (2.6%), 45 deaths (2.6%) and 216 recurrent TIAs (12.7%).

Conclusions—The short-term risk of stroke and other adverse events is substantial following the emergency department diagnosis of TIA. The presence of certain risk factors may help to identify patients who would benefit from urgent investigation.

Comments—The diagnosis of TIA can be difficult to make and it is recognised that among neurologists there is low interobserver agreement in making this diagnosis. Of the patients enrolled in this study, the accuracy of diagnosis was estimated to be 94%, based upon independent neurological review. This suggests that other conditions, such as syncope or seizure, may have prompted a number of these patients to attend the emergency department. The independent risk factors will need to be prospectively validated. As the authors themselves …