To describe presumptive risk factors (RFs) for childhood arterial ischemic stroke (AIS) and explore their relationship with presentation, age, geography, and infarct characteristics.


Children (29 days–18 years) were prospectively enrolled in the International Pediatric Stroke Study. Risk factors, defined conditions thought to be associated with childhood AIS, were divided into 10 categories. Chi-square tests were used to compare RFs prevalence across regions and age; logistic regression was used to determine whether RFs were associated with particular features at presentation or infarct characteristics.


A total of 676 children were included. No identifiable RFs was present in 54 (9%). RFs in others included arteriopathies (53%), cardiac disorders (CDs) (31%), infection (24%), acute head and neck disorders (AHNDs) (23%), acute systemic conditions (ASCs) (22%), chronic systemic conditions (CSCs) (19%), prothrombotic states (PTSs) (13%), chronic head and neck disorders (CHNDs) (10%), atherosclerosis-related RFs (2%), and other (22%). Fifty-two percent had multiple RFs. There was lower prevalence of arteriopathy in Asia, lower prevalence of CSCs in Europe and Australia, higher prevalence of PTSs in Europe, and higher prevalence of ASCs in Asia and South America. Prevalence of CDs and ASCs was highest in preschoolers, arteriopathies in children 5 to 9 years old, and CHNDs were highest in children aged 10 to 14 years. Arteriopathies were associated with focal signs and ASCs, CHNDs, and AHNDs with diffuse signs. Arteriopathies, CSCs, and ASCs were associated with multiple infarcts and CDs with hemorrhagic conversion.


RFs, especially arteriopathy, are common in childhood AIS. Variations in RFs by age or geography may inform prioritization of investigations and targeted preventative strategies. Ann Neurol 2011;69:130–140.