The ABCD2 score is a clinical prediction rule used to determine the risk for stroke in the days following a transient ischemic attack (TIA, a condition in which temporary brain dysfunction results from oxygen shortage in the brain).[1][2] Its usefulness was questioned in a 2015 review as it was not found to separate those who are at low from those who are at high risk of future problems.[3] A high score correctly predicted 87% of the people who did have a stroke in the following 7 days but also many people who did not have problems.[3]
The ABCD2 score is based on five parameters (age, blood pressure, clinical features, duration of TIA, and presence of diabetes); scores for each item are added together to produce an overall result ranging between zero and seven.[1] People found to have a high score are often sent to a specialist sooner.[1] Other clinical risk factors, such as atrial fibrillation and anticoagulation treatment, as well as ongoing or recurrent TIA, are also relevant.[1]
The ABCD2 score was proposed in 2007 as a modified version of the ABCD score of 2005 (the ABCD score did not consider the presence of diabetes).[4][5][6] In the largest study based on emergency department testing of the ABCD2 score in an acute setting, the score performed poorly in both high-risk and low-risk patients. The study found the score to be 31.6% sensitive in high-risk patients (score >5) and only 12.5% specific in low-risk patients (score ≤2).[7]
Scoring system
ABCD2 score
Age
Blood Pressure
Clinical Features
Duration of TIA
Diabetes
no point
<60 years
normal
no speech disturbance and no unilateral (one-sided) weakness
speech disturbance present but no unilateral weakness
10–59 minutes
diabetes present
2 points
–
–
unilateral weakness
≥60 minutes
–
For example, a person aged 60 (1 point) with normal blood pressure (0 point) and without diabetes (0 point) who experienced a TIA lasting 10 minutes (1 point) with a speech disturbance but no weakness on one side of the body (1 point) would score a total of 3 points.
Interpretation
The risk for stroke can be estimated from the ABCD2 score as follows:
^Rothwell PM, Giles MF, Flossmann E, et al. (2005). "A simple score (ABCD) to identify individuals at high early risk of stroke after transient ischaemic attack". Lancet. 366 (9479): 29–36. doi:10.1016/S0140-6736(05)66702-5. PMID15993230. S2CID20859717.
^Johnston SC, Rothwell PM, Nguyen-Huynh MN, et al. (January 2007). "Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack". Lancet. 369 (9558): 283–92. doi:10.1016/S0140-6736(07)60150-0. PMID17258668. S2CID9510865.
