Sleep state and the risk of seizure recurrence following a first unprovoked seizure in childhood.
In a prospective study, we have followed 347 children identified at the time of a first unprovoked seizure for a mean of 46 months. To date, 135 (39%) have experienced a seizure recurrence. In this study, we analyzed recurrence risk as a function of whether the child was asleep or awake at the time of the first seizure. The cumulative recurrence risks for children whose first seizure occurred in sleep was 28% at 0.5 years, 39% at 1 year, 53% at 2 years, and 55% at 4 years, compared with recurrence risks of 18%, 23%, 30%, and 35% at the same intervals in children whose first seizure occurred while awake (p < 0.001). The association of a first seizure during sleep with an increased recurrence risk was present primarily in children with idiopathic seizures. It occurred in both those with a normal and an abnormal EEG. On multivariable analysis, sleep state, etiology, and the EEG were statistically significant predictors of recurrence risk. In children who experienced a seizure recurrence, the recurrences occurred in the same sleep state in 73% of the cases (p < 0.0001). This was also true of subsequent recurrences. We conclude that the occurrence of a first seizure in sleep is associated with an increased risk of recurrence. Subsequent seizures, if they do occur, usually occur in the same sleep state as the initial seizure.
Shinnar
S
S
Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY 10467.
Berg
A T
AT
Ptachewich
Y
Y
Alemany
M
M
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D015999:Multivariate Analysis; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D012640:Seizures / Q000175:diagnosis / Q000209:etiology*; D012890:Sleep / Q000502:physiology*; D013226:Status Epilepticus / Q000175:diagnosis / Q000209:etiology; D013997:Time Factors