Comparison of risk factors for pediatric convulsive status epilepticus when defined as seizures ≥ 5 min versus seizures ≥ 30 min

Abstract

Purpose: To identify risk factors (RF) of pediatric convulsive status epilepticus (SE) and to determine whether defining SE as seizures ≥ 5 min (SE5) or seizures ≥ 30 min (SE30) would modify the risk factors identified.

Methods: Retrospective case-control study. We included patients 1 month to 21 years of age at the time of convulsive SE. We compared the characteristics of patients with SE (cases) versus those without SE (controls) using two different seizure duration thresholds: 5 min and 30 min.

Results: 1062 patients (54% males) were enrolled. The median (p25-p75) age at the episode was 6.4 (2.8-11.8) years. 444 (41.8%) patients had SE5 and 149 (14%) patients had SE30. On univariate analysis, risk factors for SE were not markedly different when considering a 5 or 30 min threshold. Compared to their respective controls patients with both SE5 and SE30 were younger at the age of seizure onset and at the age of SE, were on more antiepileptic drugs (AEDs) at baseline, had a higher rate of changes in AEDs in the three months prior to the episode, were more likely to have developmental delay at baseline, and a higher mortality rate. A higher baseline seizure frequency, and a higher increase in seizure frequency prior to the index episode were seen only in SE5.

Conclusion: This series identifies RF which predict convulsive SE in pediatric patients. These RF are similar when considering a 5 min or a 30 min threshold for the definition of SE.

Keywords: Children; Electroencephalogram; Epilepsy; Magnetic resonance imaging; Risk factors; Status epilepticus.