Objective:

We aimed to estimate the incidence and identify prognostic factors for febrile seizure recurrence, and to develop a simple model to stratify risks.

Background:

Febrile seizures (FS) are common in children, with approximately one-third experiencing recurrence, which often heightens parental anxiety and healthcare use. Accurate risk stratification is important for counseling and follow-up, yet data from resource-limited settings remain scarce. 

Design/Methods:

In this prospective cohort study at Children’s Hospital 2 (Ho Chi Minh City, Vietnam), we enrolled 631 children aged 1 month to 6 years with a first FS (Mar 2023–Mar 2024) and followed them through July 2025. Clinical data were obtained at enrollment and through scheduled visits or structured telephone follow-up. Multivariable Cox regression identified independent predictors, and a simple count-based model was derived. Model performance was assessed using time-dependent receiver operating characteristic analysis with 1,000 bootstrap resamples.

Results:

During a median follow-up of 1.9 years, 174 children (27.6%) experienced recurrence, corresponding to an incidence of 173 per 1,000 person-years. Fifteen children (2.4%) were lost to follow-up. The median time to recurrence was 6.4 months (IQR: 2.7–12.1). Independent predictors included age <21 months at first FS (HR: 2.02; 95% CI: 1.45–2.81), family history of FS (HR: 1.83; 95% CI: 1.34–2.49), and multiple seizures within the same febrile illness (HR: 1.60; 95% CI: 1.17–2.21). Two-year recurrence risk increased progressively from 13.8% (no predictors) to 25.8% (one), 36.5% (two), and 63.1% (three). The bootstrap-corrected AUC was 0.67 (95% CI: 0.62–0.72).

Conclusions: