Validation of the ABCD Score in Identifying Individuals at High Early Risk of Stroke After a Transient Ischemic Attack

BACKGROUND AND PURPOSE: A simple score derived in the Oxfordshire Community Stroke Project (ABCD score) was able to identify individuals at high early risk of stroke after a transient ischemic attack (TIA) both in a population-based and a hospital-referred clinic cohort. We aimed to further validate the former score in a cohort of hospitalized TIA patients. METHODS: We retrospectively reviewed the emergency room and hospital records of consecutive patients hospitalized in our neurological department with a definite TIA according to the World Health Organization (WHO) criteria during a 5-year period. The 6-point ABCD score (age or =60 years=1; blood pressure systolic 140 mm Hg and/or diastolic >90 mm Hg=1; clinical features unilateral weakness=2, speech disturbance without weakness=1, other symptom=0; duration of symptoms or =60 minutes=2) was used to stratify the 30-day stroke risk. RESULTS: The 30-day risk of stroke in the present case series (n=226) was 9.7% (95% CI, 5.8% to 13.6%). The ABCD score was highly predictive of 30-day risk of stroke (ABCD=0 to 2: 0%, ABCD=3: 3.5% 95% CI, 0% to 8.2%, ABCD=4: 7.6% 95% CI, 1.2% to 14.0%, ABCD=5: 21.3% 95% CI, 10.4% to 33.0%, ABCD=6: 31.3% 95% CI, 8.6% to 54.0%; log-rank test=23.09; df=6; P=0.0008; P for linear trend across the ABCD score levels <0.00001). After adjustment for stroke risk factors, history of previous TIA, medication use before the index TIA, and secondary prevention treatment strategies, an ABCD score of 5 to 6 was independently (P<0.001) associated with an 8-fold greater 30-day risk of stroke (hazard ratio, 8.01; 95% CI, 3.21 to 19.98). CONCLUSIONS: Our findings validate the predictive value of the ABCD score in identifying hospitalized TIA patients with a high risk of early stroke and provide further evidence for its potential applicability in clinical practice.