Incidence of Childhood Stroke and Association With Recent Infection: A Population-Based Study Using Linked Data

There are limited population-based data on the incidence and risk factors for childhood stroke, including associations with recent infection and vaccination. Therefore, we aimed to determine (1) the incidence of childhood ischemic and hemorrhagic stroke and (2) associations between a recent infection or vaccination and the risk of childhood stroke.

A population-based case-control study was undertaken using linked administrative data from 2017 to 2023 in Victoria, Australia. All residents, aged 28 days to <18 years, were included. Infections in the 60 days immediately before admission were ascertained using state-wide notifiable infections and hospital admissions data sets. Vaccinations in the 42 days immediately before admission were ascertained using the Australian Immunisation Register. Strokes were identified in state-wide hospital admissions and death registry databases. Each case of childhood stroke was matched with up to 5 nonstroke controls on age (1-year bands), sex, socioeconomic position, comorbidities, and year. Conditional logistic regression was used to examine associations between infection and vaccination with childhood stroke.

Over the 7 years, 571 childhood strokes (60% ischemic; median age 8.2 years; 44% female patients) occurred among 9,881,934 person-years (5.8 events [95% CI 5.3-6.3] per 100,000 person-years). Two in 5 patients had evidence of an infection in the preceding 60 days, with lower respiratory infections (n = 74), sepsis (n = 67), upper respiratory tract infections (n = 63), meningitis/encephalitis (n = 40), gastrointestinal tract infections (n = 28), and urinary tract infections (n = 22) being the most common. Children with stroke (vs matched controls) were more likely to have had a recent infection (cases 41.9% vs controls 18.6%; adjusted odds ratio [aOR] 2.54, 95% CI 1.97-3.27). The magnitude of this association was greater for ischemic stroke (aOR 3.39, 95% CI 2.45-4.69) than hemorrhagic stroke (aOR 1.90, 95% CI 1.24-2.90). No significant association was detected between recent vaccination and childhood stroke (cases 4.2% vs controls 2.5%; aOR 1.69, 95% CI 0.92-3.09).

We provide contemporary data on new cases of childhood stroke in Australia, using population-wide linked data. Having a recent infection doubled the risk of childhood stroke. We found no significant evidence of an association between vaccination and childhood stroke.