Circadian and ultradian patterns of epileptiform discharges differ by seizure-onset location during long-term ambulatory intracranial monitoring.
Epilepsia
; 57(9): 1495-502, 2016 09.
Article
em En
| MEDLINE
| ID: mdl-27396544
ABSTRACT
OBJECTIVE:
Previous studies reporting circadian patterns of epileptiform activity and seizures are limited by (1) short-term recording in an epilepsy monitoring unit (EMU) with altered antiepileptic drugs (AEDs) and sleep, or (2) subjective seizure diary reports. We studied circadian patterns using long-term ambulatory intracranial recordings captured by the NeuroPace RNS System.METHODS:
Retrospective study of RNS System trial participants with stable detection parameters over a continuous 84-day period. We analyzed all detections and long device-detected epileptiform events (long episodes) and defined a subset of subjects in whom long episodes represented electrographic seizures (LE-SZ). Spectrum resampling determined the dominant frequency periodicity and cosinor analysis identified significant circadian peaks in detected activity. Chi-square analysis was used to compare subjects grouped by region of seizure onset.RESULTS:
In the 134 subjects, detections showed a strongly circadian and uniform pattern irrespective of region of onset that peaked during normal sleep hours. In contrast, long episodes and LE-SZ patterns varied by region. Neocortical regions had a monophasic, nocturnally dominant rhythm, whereas limbic regions showed a more complex pattern and diurnal peak. Rhythms in some individual limbic subjects were best fit by a dual oscillator (circadian + ultradian) model.SIGNIFICANCE:
Epileptiform activity has a strong 24 h periodicity with peak nocturnal occurrence. Limbic and neocortical epilepsy show divergent circadian influences. These findings confirm that circadian patterns of epileptiform activity vary by seizure-onset zone, with implications for treatment and safety, including SUDEP.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Convulsões
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Ritmo Circadiano
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Monitorização Ambulatorial
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Ondas Encefálicas
Tipo de estudo:
Observational_studies
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Prognostic_studies
Limite:
Adolescent
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Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Epilepsia
Ano de publicação:
2016
Tipo de documento:
Article