Factors associated with first recurrence of accidental foreign body incidents: a retrospective cohort study in children

Background Foreign body incidents are common pediatric emergencies, but evidence on factors associated with first recurrence is limited. This study aims to identify risk factors for first recurrence using large single-center data. Methods We conducted a retrospective cohort study of 48 197 children at a tertiary hospital (2020–2025). Kaplan-Meier analysis and multivariate Cox regression were performed. Schoenfeld residuals assessed the PH assumption; piecewise Cox models served as sensitivity analyses for age group and anatomical location, which violated it. Results In a large single-center retrospective cohort of 48 197 children (median follow-up 1096 days), 3469 (7.2%) experienced a first recurrence. Adjusted recurrence hazards were higher for children aged 3 to <7 years (hazard ratio (HR)=1.19, 95% confidence interval (CI) 1.08 to 1.31), 1 to <3 years (HR=1.51, 95% CI 1.37 to 1.66) and <1 year (HR=1.30, 95% CI 1.10 to 1.55) than for children aged ≥7 years. Compared with the location of respiratory tract incidents, hazards were higher for the urogenital tract (HR=5.13, 95% CI 4.29 to 6.14) and soft-tissue incidents (HR=1.39, 95% CI 1.20 to 1.61), but lower for the digestive tract (HR=0.86, 95% CI 0.79 to 0.94) and nasal incidents (HR=0.85, 95% CI 0.77 to 0.95). Piecewise Cox regression in follow-up-window analyses showed that associations with age and anatomical location varied over time. Conclusions Recurrence risk after a first foreign-body event in children varies during follow-up. These findings may help clinicians identify children, particularly younger children and those with urogenital foreign-body events, who could benefit from targeted caregiver counseling and early follow-up. Risk-stratified prevention strategies could account for the time-varying nature of risk recurrence.