Temporal trends in pediatric intestinal intussusception following the COVID-19 outbreak in Seoul, Korea.

Background: The COVID-19 pandemic led to significant epidemiological shifts in various diseases due to reduced interpersonal contact. This study examined changes in pediatric intestinal intussusception incidence, a disease with unclear etiology, during the pandemic.

Methods: Weekly intussusception cases in children ≤10 years old in Seoul (2009-2022) were collected from the Health Insurance Review and Assessment Service (HIRA). Trends were analyzed using spline functions, and breakpoints were identified via student methods. Bayesian Structural Time Series (BSTS) models assessed incidence changes relative to predicted values. Cases were stratified by surgical intervention, and the complicated-to-uncomplicated case ratio was evaluated.

Results: A sharp decline in intussusception incidence was observed around 2020, with breakpoints aligning with the first reported COVID-19 case. Post-breakpoint, total cases decreased by 58.8% (95% CrI: -79.0%, 7.8%), with reductions of 62.4% (95% CrI: -78.9%, -20.2%) for uncomplicated cases and 51.1% (95% CrI: -62.6%, -33.8%) for complicated cases. The complicated-to-uncomplicated ratio increased by 43.3% (95% CrI: 13.0%, 87.1%). When analyzing only the post-COVID-19 period, total and uncomplicated cases increased by 23.1% (95% CrI: 5.7%, 45.5%) from May 2022, but the change in ratio was not statistically significant.

Conclusion: Pediatric intussusception incidence significantly declined following COVID-19 onset, supporting a link between disease occurrence and contact or infectious exposure.