Staring into space, lack of responsiveness ... As International Epilepsy Day approaches, focus on epilepsy-absence.

Loss of consciousness followed by a fall and generalized tremors… Everyone thinks they can recognize a seizure . But this type of epilepsy, called tonicoclonic, is just one form among many. One of them, mainly affecting children and adolescents, is manifested by repeated absences: we speak of epilepsy-absence. " It is as if the patient were taking a break for a few seconds," explains Professor Stéphane Auvin, pediatric neurologist at Robert Debré hospital in Paris . We observe a break in contact associated with fixed gaze with stopping and then resuming the activity in progress. ”

This crisis, following the sudden change in the electrical activity of a cluster of neurons in an area of ​​the brain, causes loss of consciousness for 5 to 20 seconds. "During an absence, the information that arrives at the cortex is unstructured and therefore cannot be made aware ," specifies Professor Stéphane Charpier, professor of neurosciences at the Sorbonne University and director of research at the Institute of the Brain and the Spinal cord ( ICM) in Paris. The individual disconnects then reconnects without realizing it, a bit as if time stood still for a brief moment. ”

Childhood epilepsy: 10% of childhood epilepsy

Two types of absence epilepsies are particularly observed: that which affects children and those which occur during adolescence. The first is the most common. It manifests itself by the appearance overnight of about twenty to a hundred daily seizures. What does not go unnoticed. "The most classic situation is the teacher who spots brief stops in activities in one of her students" , explains Professor Auvin.

Probably of genetic origin, this disease affects children from 4 to 12 years old, with a peak around 6-7 years. It represents about 10% of childhood epilepsies. Knowing that epilepsy, all forms combined, affects 1% of the population, epilepsy-absence in children therefore remains rare.

It is diagnosed by a neurologist using an electroencephalogram (EEG), a test that measures the electrical activity of the brain. Usually, this disease is treated well with anti-epileptic drugs which prevent seizures in 95% of patients. However, their significant side effects (weight gain, digestive and skin disorders mainly) require adaptation on a case-by-case basis in order to promote proper intake of the treatment. After two years without a seizure, stopping the drugs can be considered. Only one in ten patients will relapse in their lifetime.

In addition to the treatments, "it is essential to detect an attention deficit that is found in 30% of children with epilepsy-absence ," adds Professor Auvin. Appropriate management of this associated disorder is fundamental so that schooling can proceed correctly ” .

Adolescent absence epilepsy: more complex management

Very similar to that of children, adolescent absence epilepsy appears later, between 10 and 16 years old, with a peak around 14 years old. It is however distinguished by shorter and less frequent absence seizures, which can easily go unnoticed, and above all by the presence of associated tremor seizures, non-existent in epilespy-absence of the child. The other major difference is the need for long-term treatment because of the high risk of recurrence when the drugs are stopped.

“These specificities have significant repercussions on the quality of life,” underlines Pr Auvin . During adolescence, a period of transition, it is sometimes difficult to establish good adherence to antiepileptic treatment. Parental supervision, which is often necessary, is not always welcomed by the adolescent ” . Because even if the treatment makes it possible to control the disease well, forgetting to take considerably increases the risk of the appearance of a seizure. The significant consequences on autonomy, studies or even obtaining a driving license therefore require rigorous monitoring by a neurologist.

"It is also essential to break the false beliefs conveyed about these pathologies", notes Dr. Cuvellier, such as those circulating around video games. The absence epilepsies are generally not accompanied by photosensitivity, the flashes of light are not likely to trigger seizures. In addition, most physical and daily activities can be performed without problem when the disease is under control. Only a few extreme sports, such as mountaineering or parachuting, are contraindicated.