Circadian distribution and sleep/wake patterns of generalized seizures in children

Abstract

Purpose: To evaluate the relationship of sleep/awake and circadian patterns to generalized seizures. Methods: Charts of 1,044 consecutive pediatric epilepsy patients undergoing video-electroencephalography (EEG) monitoring (vEEG) over 5 years were reviewed: 962 patients were excluded due to focal epilepsy (556), nonepileptic recorded events (217), missing data (125), age over 21 years (59), and no recorded events or seizures (10). Seizure semiology of recorded seizures with generalized onset on EEG was classified according to the International League Against Epilepsy (ILAE) seizure semiology terminology, and analyzed based on occurrence during day (6 a.m. to 6 p.m.) or night and on their relationship to wakefulness and sleep, with calculated occurrence in 3-h time blocks throughout 24 h. Statistical analysis was performed with binomial testing. Key Findings: Three-hundred sixteen generalized seizures were analyzed in 77 children. Mean age was 6.4 years ± 5.4 (range 0.33-20 years), including 50.6% girls. Tonic and tonic-clonic seizures were more frequently seen in sleep, whereas all other generalized semiologic seizure types occurred more frequently out of wakefulness. Clonic seizures had two peaks: (6-9 a.m.) and (noon to 3 p.m.) in wakefulness. Absence seizures occurred predominantly in wakefulness, (9 a.m. to noon and 6 p.m. to midnight). Atonic seizures occurred predominantly in wakefulness (noon to 6 p.m.). Myoclonic seizures occurred in wakefulness (6 a.m. to noon). Epileptic spasms had two peaks: (6-9 a.m. and 3-6 p.m.) in wakefulness. Significance: Circadian pattern and sleep-wake patterns are important considerations in characterization of generalized seizure types. Recognition and characterization of individual diurnal seizure patterns offer new diagnostic and therapeutic options, including EEG or long-term video EEG monitoring scheduling, differential (day/night) medication dosing, and a better understanding of pathophysiologic mechanisms underlying circadian patterns of epilepsy. © Wiley Periodicals, Inc. © 2011 International League Against Epilepsy.