Prevalence of epileptiform discharges in healthy children--new data from a prospective study using digital EEG

Data on epileptiform electroencephalography (EEG) discharges in healthy children are limited, with published studies dating back more than 20 years. Moreover, analyses have been performed exclusively using paper-recorded EEG, and reported prevalences differ significantly. With recent reports using these data as reference suggesting an increased prevalence of epileptiform EEG discharges in children with behavioral disturbances, acquisition of exact prevalence data has become even more critical. The aim of our study was to analyze the frequency of epileptiform EEG discharges in healthy children using digitally recorded EEG (DEEG) and to compare these data to those of previously published studies.

Prospective analysis of DEEG was performed in 382 healthy children (226 male, 156 female) ages 6-13 years admitted to our hospital for minor head trauma. Recording was carried out for a minimum of 20 min including hyperventilation and photic stimulation. Analysis was carried out by two board-certified clinical neurophysiologists.

Epileptiform EEG discharges were detected in 25 of 382 children (11 of 226 male, 14 of 156 female) corresponding to an overall prevalence of 6.5%. Of these 25 children, 4 had either generalized or bifrontal spikes, 12 showed constant localized focal discharges, and 9 showed multifocal discharges. Compared to previous studies using non-DEEG recording, the prevalence of epileptiform EEG discharges in our population was significantly higher. No significant difference was found when comparing our data to prevalences recently reported in children with behavioral disturbances using DEEG.

Our study further highlights the urgent need to reevaluate the prevalence of epileptiform EEG discharges in healthy children using DEEG recordings in a large cohort.