[Sudden death of epileptic patients]

Sudden unexpected death in an epileptic patient which no likely cause--head trauma, drowning, grand mal, bronchial aspiration, suffocation--and no anatomic or toxicologic condition which could clearly explain the death. A seizure reported by witnesses or suspected from clinical signs observed prior to death and compatible with the definition raises the problematic of the relationship with sudden death.

Sudden death is estimated to occur in 1 out of 450 to 2000 epileptic patients, giving an annual incidence of 0.55 to 9.3 per 1000 patients. Such a wide incidence range can be explained by the difficulties in providing a rigorous definition of sudden death and more importantly by the heterogeneous nature of the population at risk. The risk of sudden death is clearly related to the severity of the epilepsy. It is observed in young adults with symptomatic, often difficult to treat epilepsy. Death is frequently observed during sleep.

The circumstances of sudden death in the epileptic patient illustrate the complex relationships existing between seizures and irreversible cardiorespiratory dysfunction. Neurogenic lung edema is frequently observed at autopsy and has been confirmed by experimental data. Experimental work and clinical observations would suggest that central apnea, associated with cardiac dysrhythmia could be involved. Other risk factors, including sleep, compliance to treatment, arrhythmogenic effect of certain antiepileptics and the consequences of repeated seizures on the myocardium may also play a role.