Semin Neurol 2022; 42(05): 658-664
DOI: 10.1055/a-1960-1355
Review Article

Sudden Unexpected Death in Epilepsy: Pathogenesis, Risk Factors, and Prevention

Babitha Haridas
1   Department of Neurology, Johns Hopkins School of Medicine, Baltimore, Maryland
David T. Chuang
2   Department of Neurology, Weill Cornell School of Medicine, New York, New York
Maromi Nei
3   Department of Neurology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania
Joon Y. Kang
1   Department of Neurology, Johns Hopkins School of Medicine, Baltimore, Maryland
› Author Affiliations
Funding B.H.: Nothing to disclose. J.Y.K.: Nothing to disclose. D.T.C.: Receives research funding from Eisai. M.N.: Clinical research support from Eisai and UCB Pharma.


Sudden unexpected death in epilepsy (SUDEP) is a tragic and unexpected cause of death in patients with a known diagnosis of epilepsy. It occurs in up to 6.3 to 9.3/1,000 patients with drug-resistant epilepsy. The main three risk factors associated with SUDEP are the presence of generalized tonic–clonic seizures, the presence of a seizure in the past year, and an intellectual disability. There are several mechanisms that can result in SUDEP. The most likely sequence of events appears to be a convulsive seizure, overactivation of the autonomic nervous system, cardiorespiratory dysfunction, and death. While the risk of SUDEP is relatively high in patients with drug-resistant epilepsy, studies indicate that more than 50% of patients and caregivers are unaware of the diagnosis. Counseling about the diagnosis and preventative measures at the time of diagnosis is important. There are numerous interventions that may reduce the risk of SUDEP, including conservative measures such as nocturnal surveillance with a bed partner (where applicable) and automated devices. Optimizing seizure control with antiseizure medications and surgical interventions can result in a reduced risk of SUDEP.

Publication History

Accepted Manuscript online:
12 October 2022

Article published online:
28 November 2022

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