Abstract W MP70: Short and Long-term Risk of Stroke After a Transient Neurological Attack (TNA) versus TIA: Population-based Study

BACKGROUND: The distinction between a TIA and a transient neurological attack (TNA i.e. a TIA-like event not satisfying the NINDS Criteria for a clinically definite TIA) has important implications for clinical practice. Patients with TIA require intensive long-term secondary prevention of stroke, but there are conflicting estimates of the risk of stroke after TNA. METHODS: In a United Kingdom population-based study (Oxford Vascular Study) of all incident and recurrent TNAs and TIAs from 2002-2012, we prospectively classified all first events in the study period as TIAs (based on NINDs criteria) versus TNAs (including isolated transient neurological symptoms not satisfying the NINDS criteria) versus other conditions (migraine aura, epilepsy, etc). Kaplan-Meyer (KM) risk of stroke was determined at 10-years by long term regular face-to-face follow up. RESULTS: Among 1648 first events, 594 were NINDS-defined TIAs (mean/SD age= 73.5/13.1 years), 658 were TNAs (67.1/15.5) and 396 were other diagnosis (62.8/18....