Sudden unexpected death in epilepsy: The neuro-cardio-respiratory connection

Sudden unexpected death in epilepsy (SUDEP) is the major cause of epilepsy-related premature mortality which targets preferentially younger people. Its etiology remains unknown. Several risk factors have been identified with generalized tonic-clonic seizures as the most important one; seizure control remains the most effective measure of prevention. Although some cases may be attributable to cardiac causes, mainly undiagnosed cardiac channelopathies, the majority appear linked to epilepsy-related disruption of the functional connectivity of certain brain structures associated with the central autonomic control of cardio-respiratory function (neuro-cardio-respiratory connection). Obtaining further data on its pathophysiologic mechanisms is a cardinal step towards preventing and reducing the incidence of SUDEP. Neuroimaging and molecular genetic studies may provide insights into the causes of SUDEP and identify potential biomarkers for risk stratification of patients susceptible to SUDEP. These issues are herein reviewed with emphasis placed on the neuro-cardio-respiratory functions affected by epilepsy and their genetic control and influences.