LAUSR

Background and Purpose: Etiologic subtypes of ischemic strokes are influenced by the vascular risk factors profile of patients. Strict management of hypertension and dyslipidemia may have an impact on the prevalence of atherosclerosis. We evaluated changes in the proportion of different ischemic stroke etiologies during the last 22 years. Methods: We studied patients with acute ischemic strokes admitted to a single institution between 1997 and 2018. Demographics, VRF, treatments prior to admission and TOAST subtypes of ischemic strokes were assessed. These variables were compared between 2 periods: 1997-2007 (P1) and 2008-2018 (P2). Results: There were 2747 patients (64% men, aged 66.6 ±14.9 years), 920 subjects in P1 and 1827 in P2. Age and gender distribution did not change over time. Proportion of large artery atherothrombotic strokes decreased from 29% in P1 to 14% in P2 (p <0.0001) and small vessel strokes from 15% in P1 to 11% in P2 (p <0.05). Cardioembolic and undetermined strokes increased from 17 to 25% (p <0.0001) and from 30% to 41% (p <0.0001), respectively. Detection of atrial fibrillation increased from 10% to 19% (p<0.00001). Use of medication prior to stroke increased for aspirin from 27% in P1 to 45% in P2 (p <0.0001), for antihypertensive drugs from 26% to 62% (p <0.0001), for statins from 14% to 42% (p <0.0001) and for anticoagulants from 4% to 9% (p<0.0001). Conclusion: The proportion of strokes associated to large and small vessel atherosclerosis is declining with a substantial increase in the proportion of cardioembolic and undetermined strokes. Higher rates of use of preventive medications and higher prevalence and/or better screening for atrial fibrillation could explain, at least in part, these findings.