Abstract T P313: Sensitivity of ICD-9 Discharge Codes to Identify TIA Cases in 4 Community-Based Emergency Departments

Introduction: The diagnosis of TIA is often challenging in the emergency department (ED) setting. ICD-9 discharge code 435 is often used to identify TIA cases; however, its accuracy is unclear. Our objective was to determine the sensitivity of ICD-9 code 435 to identify confirmed TIA cases treated in 4 community-based EDs. Methods: Over a 12 month period suspect TIA cases were prospectively identified using hot-pursuit mechanisms in 4 EDs. A time-based definition of TIA was used (i.e., acute onset focal unilateral symptoms with duration <24 hours and no alternative diagnosis). All cases had a final clinical diagnosis of TIA confirmed following an independent physician panel review. Data were abstracted from medical charts and the primary ICD-9 discharge code was obtained from the hospital or ED billing records. ICD-9 discharge codes were neither used to identify cases or confirm the final diagnosis. Results: Of 366 subjects with suspected TIA, 336 (92%) had a confirmed final diagnosis of TIA. Mean age was...