How long do new-onset seizures in children last?
Article first published online: 2 APR 2001
Copyright © 2001 Wiley-Liss, Inc.
Annals of Neurology
Volume 49, Issue 5, pages 659–664, 1 May 2001
How to Cite
Shinnar, S., Berg, A. T., Moshe, S. L. and Shinnar, R. (2001), How long do new-onset seizures in children last?. Ann Neurol., 49: 659–664. doi: 10.1002/ana.1018
- Issue published online: 26 APR 2001
- Article first published online: 2 APR 2001
- Manuscript Accepted: 3 DEC 2000
- Manuscript Revised: 1 DEC 2000
- Manuscript Received: 10 APR 2000
- National Institute of Neurological Disorders and Stroke. Grant Number: R01 NS26151
Although there are data on the duration of seizures in patients with refractory epilepsy, little is known about the duration of seizures in nonrefractory epilepsy populations. In a prospective study, seizure duration was determined in 407 children with a first unprovoked seizure using a structured interview and review of medical and ambulance records. Analysis focused on the distribution of seizure duration and on the conditional probability that a seizure would stop once it had already lasted for a specified time. Seizures lasted ≥5 minutes in 50% of cases, ≥10 minutes in 29%, ≥20 minutes in 16%, and ≥30 minutes in 12%. Seizure duration data were best fit as the sum of two exponential distributions, one with a mean of 3.6 minutes accounting for 76% of cases and the other with a mean of 31 minutes accounting for 24% of cases. The longer a seizure lasted, the less likely it was to stop within the next few minutes. In the 182 children with 2 or more seizures, the durations of the first and second seizures were highly correlated (r = 0.395, p < 0.0001). We conclude that the distribution of seizure duration in children with a first unprovoked seizure differs markedly from that observed in patients with refractory epilepsy. A subgroup of patients are predisposed to prolonged seizures. The data suggest that, once a seizure lasts for more than 5–10 minutes, it is unlikely to stop spontaneously within the next few minutes, and intervention is therefore indicated. These findings also support the continued use of the current definition of status epilepticus as a seizure lasting for 30 minutes or longer for epidemiologic studies.