Febrile seizures and childhood epilepsy and risk of internalizing and psychotic symptoms.

Objective: To assess whether children with febrile seizures and/or epilepsy were at increased risk of experiencing internalizing symptoms or psychotic-like experiences at age 11 years.

Methods: This cohort study includes 44 819 children from the 11-year follow up of the Danish National Birth Cohort. Information on childhood seizures was retrieved from the Danish National Patient Registry, whereas child psychiatric symptoms were assessed in a web-based questionnaire using the Adolescent Psychotic-like Symptom Screener and the Strength and Difficulties Questionnaire. Adjusted odds ratios (aORs) with corresponding 95% confidence intervals (CIs) for the association between childhood seizures and internalizing symptoms (symptom score ≥8) and psychotic-like experiences (≥2 definite experiences) were obtained using logistic regression models.

Results: A total of 1620 children with febrile seizures (3.6%), and 311 children with epilepsy (0.7%) were identified. When adjusted for potential confounders, no association between febrile seizures and psychiatric symptoms was observed, and no association was observed between epilepsy and psychotic-like experiences. However, the OR for internalizing symptoms was 1.76 (95% CI: 1.20-2.58) in children with epilepsy compared to children without. This higher risk was evident mainly in boys (OR 2.30, 95% CI 1.37-3.85), children with ≥2 epilepsy-related hospital admissions (OR 2.79, 95% CI 1.81-4.32), and children whose age at first epilepsy-related hospital admission was 0-3 years (OR 2.47, 95% CI 1.45-4.19).

Significance: No association was found between febrile seizures and psychiatric symptoms or epilepsy and psychotic-like experiences at age 11. However, boys with epilepsy were at higher risk of experiencing internalizing symptoms.