Which child will have a febrile seizure?

OBJECTIVE: To identify risk factors predictive of a first febrile seizure.

DESIGN: Case-control study.

SETTING: Regional referral pediatric hospital emergency department.

PATIENTS: Seventy-five patients aged 6 months to 4 years presenting with a first febrile seizure were age-matched to two febrile and two afebrile noninfectious controls who had never had a seizure.

METHODS: Telephone interview of parents.

MAIN OUTCOME MEASURES: Risk factors assessed included family history of febrile or afebrile seizures, neurodevelopmental abnormality, and child-care arrangement. Analysis was done by matched case-control and logistic regression.

RESULTS: Factors associated with a significant increase in risk of a first febrile seizure were febrile seizures in first-degree relative (odds ratio [OR], 4.5) or second-degree relative (OR, 3.5); neonatal discharge at 28 days or later (OR, 5.6); parental report of "slow" development (OR, 4.9); and day-care attendance (OR, 3.1). For children with two risk factors (an estimated 3% of the population), the risk of developing febrile seizures is approximately 28% (assuming a population incidence of febrile seizures of 4%).