Abstract T P199: An External Network Validation of the TeleStroke Mimic Score: A Prediction Rule for Identifying Stroke Mimics Evaluated during Telestroke Encounters

Abstract

Introduction: Up to 30% of acute stroke evaluations are deemed stroke mimics, and these are common in telestroke as well. We recently published our risk prediction score for use during telestroke encounters to differentiate telestroke mimics (SM) from ischemic cerebrovascular disease (iCVD). Using data from the University of Utah Telestroke Program, we sought to externally validate the TM score. Methods: We evaluated the TM risk score in 190 telestroke consults performed at the University of Utah Telestroke Program from Nov 2010 to Jun 2014 by use of ROC curve analysis. The TM score = (Age multiplied by 0.2) + 6 (Hx of atrial fib) + 3 (Hx of HTN) + 9 (facial weakness) + 5 (NIHSS > 14) - 6 (Hx of seizure). Lower TM scores yield higher chances of being a stroke mimic. Results: Based on final clinical diagnosis, there were 86/190 (45.3%) SM in the external validation cohort. We tested only those characteristics that were previously shown to be associated with SM through inclusion in the TM score (Table 1). Of the 6 TM elements, 3 items were not significantly different between SM and iCVD (A. Fib, hypertension and age). Despite this, the TM Score validated well on ROC curve analysis with AUC of 0.70, similar to what was reported during the development and validation of the score at our center. Conclusion: As telestroke consultation expands, increasing numbers of SM patients are being evaluated. These patients differ substantially from their iCVD counterparts in their vascular risk profiles and other characteristics. Decision-support tools based on predictive models may help highlight these differences during complex, time-critical telestroke evaluations. Further validation is desirable.