Pediatric Acute Ischemic Stroke by Age-Group: A Systematic Review and Meta-Analysis of Published Studies and Hospitalization Records.

Background: Although stroke is rare among the pediatric population, it is nevertheless associated with serious or life-threatening consequences. The etiologic factors of acute ischemic stroke (AIS) are likely to vary over the course of childhood development. The incidence rates of AIS, not previously systematically examined by pediatric age subgroup, could guide studies of its etiology.

Objective: The aim of this study is to evaluate the incidence rate of AIS by age-group in the pediatric population (aged 0-17/18 years) and identify any common trends or sources of variability across different countries.

Methods: Rates of pediatric AIS were collated from a systematic literature review of published studies globally (1983-2020) and hospitalization records from Europe and the USA (2015-2018). Records that were included in the analysis reported the code or description used for AIS diagnosis and age-specific data for children aged 0-17/18 years. AIS incidence rates were summarized by age-group, data source, country, and geographic region. A meta-analysis was conducted to assess the heterogeneity of AIS rates in neonates.

Results: The pooled AIS incidence rate was 5.6 per 100,000 children across all records. When only records reporting the AIS incidence rates for children across the full age range (0-17/18 years) were analyzed, the pooled AIS incidence rate was 4.6 per 100,000 children and ranged from 7.0 per 100,000 (Germany) to 1.3 per 100,000 (Denmark). The highest pooled rates were observed in the 0-28-day age-group (24.6 per 100,000 live births), declining to the lowest rates in the 5-9-year age-group, and rising again in the 10-17/18-year age-group. AIS rates were the most heterogeneous in the 0-28-day age-group and across European countries. Significantly higher AIS rates in neonates were observed from hospital databases (35.9 per 100,000) than in the literature (19.4 per 100,000). AIS rates may be underestimated as pediatric AIS events are rare and challenging to diagnose, and limited age-specific data are available.

Conclusions: Incidence rates of pediatric AIS by age-groups followed a consistent overall pattern of a reverse J-shaped curve, with the highest rates in neonates, across predominantly European and North American countries. Further research is warranted to examine if this pattern is observed in other geographic regions and to identify AIS risk factors specific to different phases of childhood development.