Temporal trends in the use of investigations after stroke or transient ischemic attack

Background — Guidelines recommend that patients with stroke or transient ischemic attack (TIA) undergo neuroimaging and cardiac investigations to determine etiology and guide treatment. It is not known how the use of these investigations has changed over time and whether there have been associated changes in management.

Objectives — To evaluate temporal trends in the use of brain and vascular imaging, echocardiography, and antithrombotic and surgical therapy after stroke or TIA.

Research Design — We analyzed 42,738 patients with stroke or TIA presenting to any of the 11 regional stroke centers in Ontario, Canada between 2003 and 2012 using the Ontario Stroke Registry database. The study period was divided into 1-year intervals and we used the Cochran-Armitage test to determine trends over time.

Results — Between 2003/2004 and 2011/2012, the proportion of patients undergoing brain imaging increased from 96% to 99%, as did the proportion receiving ≥3 brain scans (21%-39%), magnetic resonance imaging (13%-50%), vascular imaging (62%-88%), or echocardiography (52%-70%) (P<0.0001 for all comparisons). There was an increase in the proportion receiving any antithrombotic therapy (83%-91%, P<0.0001) but no change in use of anticoagulation (25% overall and 68% in subgroup with atrial fibrillation) or carotid revascularization (1.4%-1.5%, P=0.49).

Conclusions — The use of investigations after stroke has increased over time without concomitant changes in medical or surgical management. Although initial neurovascular imaging is in accordance with practice guidelines, the use of multiple imaging procedures and routine echocardiography are of uncertain clinical effectiveness.