Do seizures and epileptic activity worsen epilepsy and deteriorate cognitive function?
Version of Record online: 13 NOV 2013
Wiley Periodicals, Inc. © 2013 International League Against Epilepsy
Special Issue: Epileptic Encephalopathies: Proceedings of the International Sicilian Workshop, Sciacca, April 29–30, 2012
Volume 54, Issue Supplement s8, pages 14–21, November 2013
How to Cite
Avanzini, G., Depaulis, A., Tassinari, A. and de Curtis, M. (2013), Do seizures and epileptic activity worsen epilepsy and deteriorate cognitive function?. Epilepsia, 54: 14–21. doi: 10.1111/epi.12418
- Issue online: 13 NOV 2013
- Version of Record online: 13 NOV 2013
- Epileptogenic process;
- Epilepsy progression;
- Sleep disruption;
- Status epilepticus
Relevant to the definition of epileptic encephalopathy (EE) is the concept that the epileptic activity itself may contribute to bad outcomes, both in terms of epilepsy and cognition, above and beyond what might be expected from the underlying pathology alone, and that these can worsen over time. The review of the clinical and experimental evidence that seizures or interictal electroencephalography (EEG) discharges themselves can induce a progression toward more severe epilepsy and a regression of brain function leads to the following conclusions:
- The possibility of seizure-dependent worsening is by no means a general one but is limited to some types of epilepsy, namely mesial temporal lobe epilepsy (MTLE) and EEs.
- Clinical and experimental data concur in indicating that prolonged seizures/status epilepticus (SE) are a risky initial event that can set in motion an epileptogenic process leading to persistent, possibly drug-refractory epilepsies.
- The mechanisms for SE-related epileptogenic process are incompletely known; they seem to involve inflammation and/or glutamatergic transmission.
- The evidence of the role of recurrent individual seizures in sustaining epilepsy progression is ambiguous. The correlation between high seizure frequency and bad outcome does not necessarily demonstrate a cause–effect relationship, rather high seizure frequency and bad outcome can both depend on a particularly aggressive epileptogenic process.
- The results of EE studies challenge the idea of a common seizure-dependent mechanism for epilepsy progression/intellectual deterioration.