Recurrent Ischemic Stroke – A Systematic Review and Meta-Analysis

Abstract Objectives Recurrent stroke remains a challenge though secondary prevention is initiated immediately post-stroke. Stroke subtype may determine the risk of recurrent stroke and require specific preventive measures. We aimed to identify subtype-specific stroke recurrence and associated risk factors over time. Methods and materials A systematic review was performed using PubMed and Embase for studies including adults >18 years, first-ever ischemic stroke in population-based observational studies or registries, documented TOAST-criteria and minimum 1-year follow-up. Meta-analysis on stroke recurrence rate was performed. Final search: November 2019. Results The search retrieved 26 studies (between 1997 and 2019). Stroke recurrence rate ranged from 5.7% to 51.3%. Recurrent stroke was most frequent in large artery atherosclerosis (LAA) and cardioembolic (CE) stroke with recurrent stroke similar to index stroke subtype. We identified a lower recurrence rate for small vessel occlusion (SVO) stroke with recurrence frequently of another stroke subtype. Based on a meta-analysis the summary proportion recurrence rate of recurrent stroke in studies using TOAST-criteria = 0.12 and = 0.14 in studies using TOAST-like criteria. Hypertension, diabetes mellitus, atrial fibrillation previous transient ischemic attack, and high stroke severity were independent risk factors for recurrence. Conclusion Stroke recurrence rates seem unchanged over time despite the use of secondary prevention. The highest recurrence rate is in LAA and CE stroke eliciting same subtype recurrent stroke. A lower recurrence rate is seen with SVO stroke with a more diverse recurrence pattern. Extensive workup is important in all stroke subtypes - including SVO stroke. Future research needs to identify better preventive treatment and improve compliance to risk factor prevention to reduce stroke recurrence.