Validating the ABCD2 Score for predicting stroke risk after transient ischemic attack in the ED☆
Received 11 August 2008; received in revised form 3 September 2008; accepted 13 September 2008. published online 26 October 2009.
Abstract
Objectives
The aim of the study was to validate the use of the ABCD2 score for the prediction of stroke after transient ischemic attack (TIA) in patients presenting to the emergency department (ED). The ABCD2 scoring is based on 5 factors as follows: age of at least 60 years; blood pressure of at least 140/90 mm Hg; clinical features such as unilateral weakness and speech impairment alone; duration of at least 60 minutes or 10 to 59 minutes; and diabetes.
Methods
The authors conducted a retrospective observational study of all patients presented to the ED for TIA, as diagnosed by the attending emergency physicians, for a 2-year period. Sensitivity, specificity, and negative predictive value (NPV) were calculated for risk of stroke at 2, 7, 30, and 90 days after presentation.
Results
From January 1, 2005, to December 31, 2006, there were 470 patients diagnosed with TIA at the ED. Mean age was 61.0 years (SD, 13.2), with 63.3% males. Age of at least 60 years, unilateral weakness, and duration of at least 60 minutes were found to be significant predictors of stroke at 2 days. An admission rule based on an ABCD2 score of at least 4 showed sensitivity of 86.4% and NPV of 91.7% for stroke at 7 days. Admission based on a score of at least 3 showed sensitivity of 96.6% and NPV of 96.1%. Admission rate was 69.1% and. 83.6%, respectively.
Conclusion
The ABCD2 rule showed good sensitivity and NPV for stroke at 7 days. However, NPV was not 100%, and there would still be patients being discharged from the ED and returning with a stroke if this cutoff was implemented in our setting.
aDepartment of Emergency Medicine, Singapore General Hospital, 169608, Singapore
bBiostatistics Unit, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore
cYong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore
☆ This study was presented at Ninth Society for Emergency Medicine in Singapore Annual Scientific Meeting, Singapore, March 7, 2008; 17th Singapore General Hospital Annual Scientific Meeting, Singapore, April 25, 2008; and Society for Academic Emergency Medicine 2008 Annual Meeting, Washington DC, June 1, 2008.
ABSTRACT