Association of metabolic syndrome with ruptured status of intracranial aneurysms in a definitively treated cohort: a retrospective cohort analysis.

Background: Metabolic syndrome (MetS) may contribute to vascular instability through systemic inflammation and endothelial dysfunction. Its association with ruptured intracranial aneurysm (IA) status remains unclear. We examined whether MetS, its burden, and its individual components were associated with ruptured status in a cohort of patients with intracranial aneurysms who underwent definitive treatment, including both ruptured aneurysms and unruptured aneurysms selected for treatment. Methods: We performed a single-center retrospective cohort analysis of patients with intracranial aneurysms who underwent endovascular treatment at Wenzhou Central Hospital between January 2018 and January 2024, including 484 unruptured and 344 ruptured aneurysms. The cohort included patients with ruptured aneurysms and patients with unruptured aneurysms selected for definitive treatment; conservatively managed unruptured aneurysms were not included. MetS was defined as the presence of at least three standard components. Multivariable logistic regression was used to evaluate associations of binary MetS, MetS score, and individual MetS components with ruptured aneurysm status. Model discrimination was assessed using receiver operating characteristic analysis. A morphology-adjusted sensitivity analysis was performed in a 400-patient imaging subsample. Results: MetS was more prevalent in the ruptured group than in the unruptured group (59.9% vs. 40.1%). Binary MetS was independently associated with ruptured status (adjusted OR 1.83, 95% CI 1.31-2.54). Higher MetS scores showed a graded association with ruptured status, although estimates were less precise at the highest score categories. Among individual components, elevated glucose (adjusted OR 2.56, 95% CI 1.84-3.56), reduced high-density lipoprotein cholesterol (adjusted OR 2.35, 95% CI 1.62-3.40), and elevated blood pressure (adjusted OR 1.71, 95% CI 1.14-2.55) showed the strongest associations. The component-based model had the highest AUC (0.711), indicating moderate discrimination. The morphology-adjusted sensitivity analysis showed broadly stable results. Conclusion: In this cohort of patients with intracranial aneurysms undergoing definitive treatment, MetS and greater MetS burden were associated with ruptured aneurysm status. Elevated glucose, reduced high-density lipoprotein cholesterol, and elevated blood pressure showed the strongest associations. These findings should be interpreted as associative rather than causal and require prospective multicenter validation.