Circadian patterns of pediatric seizures.

OBJECTIVE: To evaluate the relationship of sleep/wake and day/night pattern to various seizure subtypes and epilepsy localizations.
METHODS: Charts of 380 consecutive pediatric patients with epilepsy undergoing video-EEG (V-EEG) over 2 years were reviewed for seizure semiology, EEG localization, occurrence during the day (6 am-6 pm) or night, during wakefulness and sleep, 3-hour time blocks throughout 24 hours, and various epilepsy localizations, and etiology.
RESULTS: A total of 1,008 seizures were analyzed in 225 children (mean age 8.5 ± 5.7 years). Sleep and wakefulness predicted seizure semiology and localization more reliably than daytime and nighttime. Auras, gelastic, dyscognitive, atonic, hypomotor, and myoclonic seizures, and epileptic spasms occurred more often in wakefulness, while tonic, tonic-clonic, automotor, and hypermotor seizures occurred more frequently in sleep (p < 0.05). Clonic, atonic, myoclonic, and hypomotor seizures occurred more frequently during daytime. Hypermotor and automotor seizures occurred more frequently at night (p < 0.05). Generalized seizures (6 am-12 pm), temporal lobe seizures (9 pm-9 am), frontal lobe seizures (12 am-6 am), parietal lobe seizures (6 am-9 am), and occipital lobe seizures (9 am-noon and 3-6 pm) revealed specific circadian patterns (p < 0.05). In addition, generalized and temporal lobe seizures occurred more frequently in wakefulness, while frontal and parietal seizures occurred more frequently in sleep, independent of day or night pattern (p < 0.05).
CONCLUSION: Sleep and wakefulness, as well as time of day and night, are important considerations in proper characterization of seizure types and epilepsy localization. These findings may contribute to a better understanding of the mechanisms of nonrandom distribution of seizures, and may provide information for individualized treatment options.