Sudden unexpected death in epilepsy: mechanisms, prevalence, and prevention

Sudden unexpected death in epilepsy (SUDEP) is a fatal complication of epilepsy with incidence rates of up to nine per 1000 patient-years in candidates for epilepsy surgery. Ongoing collaborative research is aiming to improve assessment of individual SUDEP risk and to develop preventive measures based on pathophysiological considerations. This review focuses on novel findings in humans and animal models related to pathophysiology, risk factors and prevention of SUDEP. Potential mechanisms include cardiac arrhythmia, postictal cardiomyopathy, depressed autonomic function and seizure-related respiratory failure. Electrocardiography predictors of sudden cardiac death have been described in people with chronic epilepsy, but their significance for SUDEP remains to be confirmed. Epidemiological risk factors comprise male sex, young age at epilepsy onset, symptomatic cause, longer duration of epilepsy, frequent convulsive seizures and polytherapy. Efficacious adjunctive antiepileptic medication may reduce the risk of SUDEP. Novel clinical features may help to define better the individual risk of SUDEP. Potentially therapeutic strategies including pharmacological modulation of respiratory arrest and implantation of cardiac devices could reduce the risk of SUDEP in some individuals. Antiepileptic drugs lower the risk, stressing the importance of successful seizure control for prevention.