Abstract WMP77: High Early Recurrence In Symptomatic Intracranial Atherosclerosis Treated Medically In The Real World Compared To Clinical Trials

Background: While optimizing medical treatment contributed to the low recurrence risk seen in SAMMPRIS medical arm, other factors such as delayed enrollment may have contributed to this low event rate. In this study, we aim to determine the 30-day recurrence risk in a real-world setting in patients with symptomatic intracranial atherosclerosis. Methods: We used a stroke registry of a comprehensive stroke center to identify hospitalized patients with acute ischemic stroke in the setting of symptomatic intracranial atherosclerosis of the ICA, M1, vertebral, or basilar with 50-99% luminal narrowing. We excluded patients with a clear indication for anticoagulation and those who received endovascular treatment. The outcome was recurrent stroke attributed to the affected artery within 30-days. We used adjusted Cox regression models to identify factors associated with increased recurrence risk. Results: Among 131 symptomatic 50-99% intracranial stenosis hospitalizations over 3 years, 66 patients met the inclusion criteria. The mean age was 71.9 years and 51.5% were men; 75.8% were treated with best medical management (dual antiplatelet therapy/high intensity stain therapy). Over 30-day follow-up, 21.2 % had recurrent stroke, 57.1% (8/14) occurred within first 7 days. The recurrence risk was similar to another real world ICAD cohort, and higher than that seen in SAMMPRIS (Figure). While maximal medical treatment was the only factor associated with a lower rate of recurrence (OR 0.32 95% CI 0.09-1.12, p = 0.075), the recurrence rate in patients treated with maximal medical therapy (16.0%, 95% CI 8.1-29.3%) and those SAMMPRIS eligible (17.6%, 95% CI 7.9-34.9%) remained elevated. Conclusions: In patients with symptomatic ICAS, the real-world recurrence is higher than that seen in clinical trials, despite optimally using the same medical treatment strategies. This may suggest that the low risk of recurrence achieved in clinical trials may not apply to real world practice.