Pretreatment factors associated with symptomatic stroke in Moyamoya disease patients: A multicenter study

•Advanced age, female sex, diabetes, and smoking increase stroke risk in Moyamoya after bypass surgery.•Asymptomatic patients show lower stroke risk.•Managing modifiable factors may reduce stroke in Moyamoya disease patients.•Findings call for validation through future prospective studies. Moyamoya disease (MMD) is a cerebrovascular disorder marked by the progressive steno-occlusion of the bilateral internal carotid arteries and the formation of abnormal collateral vessel networks at the base of the brain. Previous studies have attempted to identify risk factors predictive of postoperative complications to improve patient management. This study aims to identify pretreatment factors associated with post-bypass symptomatic strokes in MMD patients. This study is a multicenter retrospective analysis conducted across 13 academic institutions in North America. A total of 518 patients with MMD were included. Data collected included patient demographics, disease characteristics, and follow-up duration. Stroke-free survival was analyzed using Kaplan-Meier curves. Univariate and multivariable Cox regression analyses were used to identify risk factors for symptomatic stroke. The median age of the patients was 43 years (IQR, 34–52 years), and 370 (71 %) were females. Multivariable Cox regression identified advanced age (HR 1.03, 95 % CI 1.01–1.05, p = 0.011), female sex (HR 2.03, 95 % CI 1.00–4.11, p = 0.049), diabetes mellitus (HR 2.03, 95 % CI 1.14–3.63, p = 0.016), smoking status (HR 2.27, 95 % CI 1.27–4.05, p = 0.006), and asymptomatic disease (HR 0.37, 95 % CI 0.15–0.93, p = 0.034) as significant factors associated with symptomatic stroke. Advanced age, female sex, diabetes mellitus, and smoking status were significant predictors of symptomatic stroke in MMD patients after bypass surgery. Asymptomatic patients had a reduced risk of stroke. These findings emphasize the importance of managing modifiable risk factors and the potential benefits of early detection in improving clinical outcomes for MMD patients. Further prospective studies are needed to validate these findings.