A practice guideline, prepared by the American Academy of Neurology, was published recently in Neurology.
SUDEP stands for sudden unexpected death in epilepsy. This has been recognized for many years but the specific risk has not been consistently established. People with epilepsy can die during a seizure, presumably from post- ictal respiratory depression.
SUDEP, according to the guideline, affects 1 in 4,500 children and 1 in 1,000 adults with epilepsy per year. Lifetime risk is obviously higher. Keep in mind that 4,499 of 4,500 children will not be affected and this applies to 999 out of 1,000 adults. This should be the approach in counseling patients and families as after being informed of an adverse event, people commonly overestimate that risk and this may increase anxiety greatly.
Some groups have higher risks. The most important risk factor is the frequency of generalized tonic-clonic seizures. Those with 3 or more per year have a 15-fold higher risk. Nocturnal seizures may increase risk because they are unwitnessed. Use of a remote listening device may help.
Reducing risk of generalized tonic-clonic seizures will obviously reduce risk of sudden death. Factors that further increase risk include never having been treated with an antiepileptic drug, number of drugs used overall, intellectual disability, male sex, and anti-anxiety drug use.
The following factors do not seem to increase risk: overall frequency when this includes all seizure types, medically refractory partial seizures, monotherapy vs polytherapy, frequent changes on antiepileptic drugs, structural lesion on MRI, duration of epilepsy, and age of epilepsy onset.