Risk factors for sudden unexpected death in epilepsy.

The exact mechanisms of sudden unexpected death in individuals with epilepsy (SUDEP) are unclear, and only an incomplete analysis of risk factors can be made. Clinical, epidemiologic, and electrophysiologic evidence suggests that most sudden deaths are related temporally to seizures, are unwitnessed, and that many occur during sleep. Individuals with generalized seizures, symptomatic epilepsy, severe or frequent seizures, and additional mental handicap or neurologic deficit are at greater risk, and the majority of cases probably occur in patients with chronic epilepsy. Young people are more at risk for SUDEP than older people with epilepsy, and risk factors in pediatric practice may differ from those in adult epileptology.