Abstract Body: Introduction: Pediatric stroke is a rare event associated with high morbidity and reduced quality of life. While the causes of pediatric stroke are often unclear, recent infection is thought to be a significant factor. We sought to determine the incidence of pediatric stroke in Australia and whether recent infections and vaccinations are associated with pediatric stroke.
Methods: A population-based observational study was undertaken using routinely collected and linked data from the Vaccine Safety Health Link. The cohort comprised all children, aged 28 days to 18 years, admitted to hospital between 1 Jan 2017 and 31 December 2023 in the state of Victoria, Australia. Pediatric stroke was determined using state-wide hospital admissions and death registration datasets. To examine associations with pediatric stroke, each case of pediatric stroke was matched with up to five controls based on age (within 5-year bands), sex, and month and year of admission. Using national immunization and notifiable infection registers, we examined vaccines and notifiable infections in the 60-day period before admission. Associations with pediatric stroke were examined using logistic regression, adjusted for age, sex and country of birth (Australia vs other).
Results: Among 430,368 admitted children (46% female; median age 9.1 years [interquartile range: 4.5-14.4]), 411 had a pediatric stroke (45% female; median age 7.3 years [interquartile range: 1.2-14.4 years]), corresponding to an incidence rate of 13.6 events (95% CI 12.4–15.0) per 100,000 person-years. COVID-19 and influenza were the most common notifiable infections in the previous 60 days (Figure 1). After matching, there were 411 stroke cases and 2,055 controls. Children with pediatric stroke (vs matched controls) were more likely to have had a notifiable infection in the previous 60 days (6.6% vs 3.3%; adjusted odds ratio: 2.09; [95% CI: 1.32–3.32]). There was no significant association between vaccination in the previous 60 days and pediatric stroke (6.1% vs 4.9%; adjusted odds ratio: 1.23 [95% CI: 0.77–1.94]).
Conclusions: We provide contemporary data on the incidence of pediatric stroke and show that having a recent infection doubles the odds of pediatric stroke. Vaccination was not associated with an increased risk of stroke and should be encouraged more widely to prevent infections and any downstream effect on the risk of stroke.