TIA risk stratification: What an event was and why it happened are more important than a score

In this issue of Neurology®, Wardlaw et al.¹ describe a systematic review and meta-analysis of the use of ABCD2 score at a cutpoint of ≥4 in the identification of true TIAs vs mimics, risk factors, and recurrent stroke rates. The ABCD2 score² was developed to help nonspecialists identify patients at a higher risk for stroke. In many health care systems, the ABCD2 score has been recommended for use in triaging patients into high- or low-risk categories that frequently drives the urgency of assessment. Most commonly the cutoff of <4 is used to identify low risk and ≥4 for higher risk. In the United Kingdom, financial incentives are linked to seeing patients quickly based on their ABCD2 score. In addition to identifying patients at high risk of early recurrent stroke in clinical practice, ABCD2 ≥4 has been used as an eligibility criterion in therapeutic clinical trials that include high-risk TIA.^3,4 One limitation of the current use of the ABCD2 score is that it was never specifically designed for triage at a specific cutpoint. Although the score in its entirety predicted recurrent stroke, the original article did not propose using the score in the way that has occurred.