Age-Specific Mechanisms of Sudden Death Associated With Epilepsy

Epilepsy is associated with an increased risk of sudden cardiac death (SCD), which can occur at any age. Due to low numbers of SCD events in longitudinal cohort studies of epilepsy, studies of age-specific clinical profiles have not been performed.

In this study, the authors investigated the detailed clinical characteristics of SCD associated with epilepsy in the general population, across all ages.

Individuals with a pre-SCD diagnosis of epilepsy were identified from all out-of-hospital SCD cases prospectively ascertained in Portland, Oregon since 2002 (catchment population ∼1 million) and Ventura County, California since 2015 (catchment population ∼850,000). Lifetime clinical records were evaluated for a detailed assessment of the clinical profile.

From a total of 8,287 SCD cases, we identified 356 (4.3%) with a pre-SCD history of epilepsy. The proportion of previously diagnosed epilepsy in overall SCD cases was highest among younger subjects and progressively decreased with age (from 35.3% in 1 to 10 years to 2.5% in >80 years) (P < 0.001). There was a distinct shift in the clinical profile demarcated by the 50 to 60 years decade: Younger subjects had the highest prevalence of drug-resistant epilepsy and prearrest seizures (P < 0.001). Older subjects had a significantly higher prevalence of stroke and mood disorders, and these differences were specific for SCD in epilepsy (P < 0.001).

There were significant clinical profile differences by age among individuals with epilepsy, which were observed to be specific for SCD. Age-specific mechanisms should facilitate the development of targeted prevention strategies for SCD in epilepsy.