Diagnosis could be made after only one seizure

Published: November 18 2021
Last updated: September 27 2022

Epilepsy resulting from certain causes could be diagnosed after one seizure. This is according to a new Epilepsy & Behavior study.

Dr Salvador Vergara-López and colleagues aimed to assess what causes of epilepsy could allow for a diagnosis to be made after only one unprovoked seizure.

The International League Against Epilepsy (ILAE) says that if a person has at least two unprovoked seizures more than 24 hours apart, this can be classified as epilepsy. However, it also says that one unprovoked seizure could also be diagnosed as epilepsy, if there is more than a 60% chance that there will be a second unprovoked seizure within the next 10 years.

The study authors said that the second definition is challenging, as the risk of a second seizure is different depending on the cause of epilepsy. They explained that it is difficult to find the risks among the studies that have been done so far.

The researchers reviewed the studies done to date on this topic, and found only two that were relevant. These studies concluded that there was more than 60% chance of a second seizure to occur within eight years in epilepsy with some causes. They included stroke, traumatic brain injury, cavernous or arteriovenous malformations (problems with the blood vessels in the brain) and infections of the brain.

The researchers concluded that for this group of potential causes, epilepsy could be diagnosed after only one seizure. However, they warned that the strength of the evidence is low and more studies are needed in the future.

The full study is available on the Epilepsy & Behavior website.