Effects of a Province-wide Triaging System for TIA: The ASPIRE Intervention

Background Urgent transient ischemic attack (TIA) management to reduce stroke recurrence is challenging, particularly in rural and remote areas. In Alberta, Canada despite an organized stroke system, data from 1999—2000 suggested that stroke recurrence after TIA was as high as 9.5% at 90 days. Our objective was to determine if a multi-faceted population based intervention resulted in a reduction in recurrent stroke following TIA.

Methods In this quasi-experimental health services research intervention study we implemented a TIA management algorithm across the entire province, centered around a 24-hour physician’s TIA Hotline as well as public and health provider education on TIA. From administrative databases we linked emergency department discharge abstracts to hospital discharge abstracts to identify incident TIAs and recurrent strokes at 90 days across a single payer system with validation of recurrent stroke events. The primary outcome was recurrent stroke; with a secondary composite outcome of recurrent stroke, acute coronary syndrome, and all cause death. We used an interrupted time series regression analysis of age and sex-adjusted stroke recurrence rates after TIA incorporating a two-year pre-implementation period (2007-2009), a 15 month implementation period, and a two-year post-implementation period (2010-2012). Logistic regression was used to examine outcomes that did not fit the time series model.

Results We assessed 6 715 patients pre- and 6 956 patients post-implementation. The 90-day stroke recurrence rate in the pre-ASPIRE period was 4.5% compared to 5.3% during the post-ASPIRE period. There was neither a step change (estimate 0.38; p=0.65) nor slope change (parameter estimate 0.30; p=0.12) in recurrent stroke rates associated with the ASPIRE intervention implementation period. Adjusted all-cause mortality (OR 0.71 95%CI [0.56, 0.89]) was significantly lower following the ASPIRE intervention.

Conclusions The ASPIRE TIA triaging and management interventions did not further reduce stroke recurrence in the context of an organized stroke system. The apparent lower mortality post intervention may be related to improved surveillance following events identified as TIAs but secular trends cannot be excluded.