Risk of post-revascularization stroke in Moyamoya disease: A systematic review, meta-analysis, and meta-regression.

Moyamoya disease is a progressive cerebrovascular disorder in which cerebral revascularization is the primary treatment, yet post-revascularization stroke remains a serious and inconsistently reported complication. This meta-analysis was therefore undertaken to quantify the risk of post-revascularization stroke and identify phenotype-specific predictors with the ultimate goal of informing perioperative decision making in order to improve surgical outcomes in patients with moyamoya disease. A comprehensive literature search of databases was performed through October 2025, in accordance with PRISMA guidelines and prospectively registered (CRD420251108075). Pooled odds ratios (ORs) were estimated using a restricted maximum likelihood random-effects model, with heterogeneity quantified by I². Meta‐regression was applied to explore study‐level moderators. Twenty-six studies involving 9,698 patients (mean age 40.16 ± 2.02 years; 63.57% female) met the inclusion criteria. Age (per year increase) (OR: 1.02; 1.02–1.03), diabetes mellitus (OR: 1.35; 1.15–1.58), hypertension (OR: 1.05; 1.00–1.10), smoking (OR: 1.84; 1.22–2.77), PCA involvement (OR: 2.22; 1.55–3.17), presenting ischemia (OR: 2.54; 1.54–4.16), and advanced Suzuki grade (OR: 1.20; 1.01–1.42) were associated with increased post-revascularization stroke risk. Surgical intervention reduced the risk of stroke (OR: 0.66; 0.45–0.97). In ischemic moyamoya disease, thyroid disorder, smoking, diabetes mellitus, PCA involvement, advanced Suzuki grade, and increasing age merged as the principal predictors of any post-revascularization stroke. In hemorrhagic moyamoya disease, the risk of post-revascularization stroke was more strongly associated with diabetes mellitus and increasing age. Meta-regression analyses indicated variable influence of clinical and procedural factors. Advanced age, vascular risk factors (diabetes mellitus, hypertension, and smoking), radiographic disease severity (PCA involvement and advanced Suzuki grade), and ischemic presentation were associated with an increased risk of post-revascularization stroke in moyamoya disease, with distinct predictor profiles observed across ischemic and hemorrhagic phenotypes. Revascularization was associated with a lower overall stroke risk, supporting its therapeutic benefit.