Abstract Number: Esoc2026a1631 Cerebrovascular Complications and Outcome in Reversible Cerebral Vasoconstriction Syndrome

Abstract Background and aims Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by recurrent thunderclap headaches and reversible multifocal cerebral arterial narrowing. Although prognosis is generally favorable, a subset of patients develops cerebrovascular complications that may drive long-term disability; this study aims to identify factors associated with these complications. Methods We retrospectively reviewed 348 patients with probable or definite RCVS evaluated at Mayo Clinic between 2010-2023. Diagnostic criteria were adapted from RCVS2 and ICHD-3. The primary outcome was a composite of ischemic stroke, non-aneurysmal subarachnoid hemorrhage, and intracerebral hemorrhage; secondary outcome was poor functional status (modified Rankin Scale ≥2 within one year). Univariable and multivariable logistic regression identified predictors of these outcomes. Results Cerebrovascular complications occurred in 37.6% of patients and were the strongest determinant of poor functional outcome (aOR 5.05, 95% CI 2.04–12.51). On multivariable analysis, older age (aOR per year 1.02, 95% CI 1.00–1.04) and angiographically visible vasoconstriction (aOR 3.14, 95% CI 1.85–5.33) were independently associated with higher risk of cerebrovascular complications, whereas male sex (aOR 0.55, 95% CI 0.30–0.99), thunderclap headache at presentation (aOR 0.30, 95% CI 0.11–0.86), and sexual activity as a trigger (aOR 0.19, 95% CI 0.08–0.42) were associated with lower risk of these complications. Conclusions Cerebrovascular complications are common and strongly predict disability. Angiographic vasoconstriction and older age identify patients at higher risk, whereas thunderclap headache and sexual activity as a trigger mark a more benign phenotype. These findings may guide early risk stratification and help tailored monitoring strategies. Conflict of interest Name of author: nothing to disclose.