SUDEP—Sudden Unexpected Death in Epilepsy—is a non-traumatic death unrelated to documented status epilepticus. Although rare, SUDEP accounts for up to 50% of premature deaths associated with epilepsy. Each year, 1.1 to 1.3 per 1,000 people with epilepsy—both adults and children—die from SUDEP. The mechanisms underlying SUDEP are not yet clearly established, though cardiac and respiratory disturbances are receiving particular attention. Key risk factors for SUDEP include the presence, high frequency, and nocturnal occurrence of generalized tonic-clonic seizures (GTCS); not sharing a bedroom or living space; and poor adherence to antiepileptic medication.
Apart from optimizing antiepileptic treatment, no specific prevention strategy is currently available. Further progress in understanding, predicting, and preventing SUDEP requires the identification of new biomarkers.
A study published in The Lancet Neurology and led by the REPO2MSE network—a national research network studying SUDEP in drug-resistant focal epilepsy—investigated previously unreported seizure-related biomarkers that may have a direct causal link to the mechanisms of SUDEP. Drawing on a national cohort established in 2010 that involved all French referral centers for adult epilepsy, the study demonstrates that an extratemporal location of the epileptogenic focus is a risk factor independent of other previously known clinical predictors. Conversely, peri-ictal hypoxemia does not appear to be a major risk factor for SUDEP. The study also confirms the previously reported association between SUDEP and high body mass index (BMI).
These data highlight the need for new strategies to reduce the risk of SUDEP, including, in particular, better identification and surgical management of perisylvian and frontal lobe epilepsies, as well as the prevention of excess weight.
