Abstracts

Rationale: Seizure duration has been used as a simple metric to help patients and clinicians determine if a particular event warrants further treatment, including rescue medication and/or hospitalization. Previously, the typical length of various types of seizures has been calculated from seizures recorded on EEG or video monitoring. Such seizures were said to all be mostly < 5 minutes and all < 10 minutes. Because capturing a seizure on EEG can be rare, there may be limitations to the generalizability of this data. In contrast, the free e-dairy system Seizure Tracker, has compiled descriptions of over 3 million self-reported seizures. Our objective with this study was to analyze the duration of self-reported seizures and compare this to seizure duration reported in smaller cohorts.

Methods: Patients voluntarily logged 3,143,408 seizures on Seizure Tracker from 2007-2024. Prior to analysis we eliminated 73,424 seizures without corresponding data about age or with data that was likely inaccurate (e.g. negative years old, 1000 years old). We calculated the average reported seizure duration in children (1,427,494 seizures in 10,387 patients) and in adults (753,491 seizures in 8,397 adults) in the remaining events. Because there is significant variability between patients in how many seizures were reported, we performed a second analysis where we first calculated the median seizure duration per patient and used these values alone. This was done to de-bias the results to not favor specific patients. We then determined the duration at which 90% of reported seizures had stopped.

Results: When considering all seizures experienced by adults (age >=18) and all seizures experienced by children (age < 18), in both groups 90% of all seizures ended within 4 minutes. However, when this analysis was performed using the debiased approach, 90% of children experienced seizure cessation by 10 minutes whereas 90% of adults experienced seizure cessation by 20 minutes.