Seizures in Pediatric Moyamoya: Risk Factors and Functional Outcomes

Background: Children with moyamoya arteriopathy are at high risk for stroke and seizures. Risk factors for seizures and the impact of seizures on neurological outcomes in children with moyamoya are unknown. Methods: This is a single-center retrospective cohort study of children with moyamoya evaluated between 2003 and 2021. Functional outcome was assessed using the Pediatric Stroke Outcome Measure (PSOM). Associations between clinical variables and seizure occurrence were assessed using univariate and multivariable logistic regression. Associations between clinical variables and final PSOM score were assessed using ordinal logistic regression. Results: Eighty-four patients met inclusion criteria, and 34 (40%) children experienced seizure. Factors associated with seizures included moyamoya disease (vs syndrome; odds ratio [OR] 3.43, P = 0.008) and the presence of infarcts on baseline neuroimaging (OR 5.80, P = 0.002). Factors associated with decreased likelihood of experiencing seizures included older age at initial presentation (OR 0.82, P = 0.002) and asymptomatic (radiographic) presentation (OR 0.05, P = 0.006). Both older age at presentation (adjusted OR [AOR] 0.80, P = 0.004) and incidental radiographic presentation (AOR 0.06, P = 0.022) remained significant after adjusting for potential confounders. Seizures were associated with worse functional outcomes as assessed by the PSOM (regression coefficient 2.03, P < 0.001). This association remained significant after adjusting for potential confounders (adjusted regression coefficient 1.54, P = 0.025). Conclusions: Younger age and symptomatic presentation are associated with increased likelihood of seizures among children with moyamoya. Seizures are associated with worse functional outcomes. Prospective studies should clarify how seizures impact outcomes and how effective seizure treatment modifies this relationship.