Risk markers for sudden unexpected death in epilepsy: an observational, prospective, multicentre cohort study

Area of Science:

• Neurology
• Epileptology
• Critical Care Medicine

Background:

• Sudden unexpected death in epilepsy (SUDEP) is the primary cause of epilepsy-related mortality.
• Retrospective studies identified generalized convulsive seizures, long-standing epilepsy, and solitary living as risk factors.
• Prospective identification of definitive electroclinical SUDEP biomarkers is lacking.

Purpose of the Study:

• To identify SUDEP risk markers using multimodality data and long-term follow-up.
• To prospectively ascertain electroclinical biomarkers for SUDEP.
• To develop a potential SUDEP risk index.

Main Methods:

• Prospective, multicentre observational cohort study of children and adults with epilepsy undergoing video-electroencephalographic (EEG) monitoring.
• Inclusion criteria: epilepsy diagnosis, age >2 months, video-EEG monitoring, and 6-month follow-up.
• Data collected: demographics, electroclinical, cardiorespiratory parameters, seizure frequency, medication, and mortality. Cox proportional hazards models used.

Main Results:

• 38 (1.54%) of 2468 participants died from SUDEP over 7982 person-years.
• Significant SUDEP predictors included living alone (HR 7.62), ≥3 generalized convulsive seizures/year (HR 3.1), longer ictal central apnoea (HR 1.11), and longer postictal central apnoea (HR 1.32).
• Longer ictal central apnoea was not significant in a subanalysis excluding possible/near-SUDEP cases.

Conclusions:

• Premortem peri-ictal apnoea is associated with increased SUDEP risk.
• Cardiorespiratory monitoring during seizures may aid epilepsy mortality risk assessment.
• Peri-ictal apnoea, solitary living, and convulsive seizure frequency could form a validatable SUDEP risk index.