Risk Stratification for Recurrence and Mortality in Embolic Stroke of Undetermined Source

Abstract

Background and Purpose— The risk of stroke recurrence in patients with Embolic Stroke of Undetermined Source (ESUS) is high, and the optimal antithrombotic strategy for secondary prevention is unclear. We investigated whether congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, and stroke or transient ischemic attack (TIA; CHADS 2 ) and CHA 2 DS 2 -VASc scores can stratify the long-term risk of ischemic stroke/TIA recurrence and death in ESUS. Methods— We pooled data sets of 11 stroke registries from Europe and America. ESUS was defined according to the Cryptogenic Stroke/ESUS International Working Group. Cox regression analyses were performed to investigate if prestroke CHADS 2 and congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or TIA, vascular disease, age 65–74 years, sex category (CHA 2 DS 2 -VASc) scores were independently associated with the risk of ischemic stroke/TIA recurrence or death. The Kaplan–Meier product limit method was used to estimate the cumulative probability of ischemic stroke/TIA recurrence and death in different strata of the CHADS 2 and CHA 2 DS 2 -VASc scores. Results— One hundred fifty-nine (5.6% per year) ischemic stroke/TIA recurrences and 148 (5.2% per year) deaths occurred in 1095 patients (median age, 68 years) followed-up for a median of 31 months. Compared with CHADS 2 score 0, patients with CHADS 2 score 1 and CHADS 2 score >1 had higher risk of ischemic stroke/TIA recurrence (hazard ratio [HR], 2.38; 95% confidence interval [CI], 1.41–4.00 and HR, 2.72; 95% CI, 1.68–4.40, respectively) and death (HR, 3.58; 95% CI, 1.80–7.12, and HR, 5.45; 95% CI, 2.86–10.40, respectively). Compared with low-risk CHA 2 DS 2 -VASc score, patients with high-risk CHA 2 DS 2 -VASc score had higher risk of ischemic stroke/TIA recurrence (HR, 3.35; 95% CI, 1.94–5.80) and death (HR, 13.0; 95% CI, 4.7–35.4). Conclusions— The risk of recurrent ischemic stroke/TIA and death in ESUS is reliably stratified by CHADS 2 and CHA 2 DS 2 -VASc scores. Compared with the low-risk group, patients in the high-risk CHA 2 DS 2 -VASc group have much higher risk of ischemic stroke recurrence/TIA and death, approximately 3-fold and 13-fold, respectively.