DWI Lesions and TIA Etiology Improve the Prediction of Stroke After TIA

Abstract

Background and Purpose— The ABCD 2 score has been shown to predict the early risk of stroke after transient ischemic attack (TIA). The additional predictive value of diffusion-weighted imaging (DWI) and TIA etiology is not well known. Methods— From January 2003 to June 2007, 343 consecutive patients (mean±SD age, 62.4±15.4 years) with TIA were admitted to our stroke unit. Most (339) patients underwent DWI and all had an etiologic work-up and were followed up for 3 months. The predictive value of the ABCD 2 score, positive DWI findings, large-artery atherosclerosis (LAA), and atrial fibrillation (AF) with respect to occurrence of ischemic stroke at 1 week and 3 months was assessed. Results— DWI was positive in 136 (40%) patients. Sixty (17%) patients had LAA and 27 (8%) had AF. Patients with positive DWI findings were more likely to have unilateral weakness (odds ratio [OR]=2.2; 95% CI, 1.3 to 3.7), TIA duration ≥60 minutes (OR=2.6; 95% CI, 1.3 to 5.2), ABCD 2 >5 (OR=4.7; 95% CI, 2.0 to 11.0), LAA (OR=1.8; 95% CI, 1.0 to 3.1), and AF (OR=3.5; 95% CI, 1.5 to 8.0). During follow-up, 5 patients had a stroke within 7 days (absolute risk=1.5%, 95% CI, 0.3% to 2.7%), and 10 had a stroke within 3 months (absolute risk=2.9%; 95% CI, 1.1% to 4.7%). All early strokes but 1 occurred in patients with positive DWI findings. ABCD 2 score and positive DWI findings were associated with an increased 7-day and 3-month risk of stroke. At 3 months, ABCD 2 score >5 (hazard ratio=10.1; 95% CI, 1.1 to 93.4), positive DWI result (hazard ratio=8.7; 95% CI, 1.1 to 71.0), and LAA (hazard ratio=3.4; 95% CI, 1.0 to 11.8) were independently associated with an increased risk of stroke. There was no association with AF. Conclusions— Taking DWI and TIA etiology into account in addition to the ABCD 2 score improves the prediction of the early risk of stroke after TIA.