Sudden unexpected death in epilepsy (SUDEP)
By Mayo Clinic Staff
Sudden unexpected death in epilepsy (SUDEP) is uncommon, but it is an important risk for some people with epilepsy. The risk of SUDEP differs among people. Some risk factors can be reduced.
What is SUDEP?
SUDEP is a sudden, unexpected death that can happen in people with epilepsy. It may happen with or without a seizure. Another cause of death isn't found.
SUDEP doesn't include deaths due to drowning, injury or documented prolonged seizures in people with epilepsy.
How does SUDEP happen?
Researchers don't know exactly how SUDEP happens. Some research suggests that a tonic-clonic seizure can lead to changes in breathing and brain function involved in breathing and waking up.
Your heart rate and rhythm also can change during or after seizures. In SUDEP events that have been monitored, breathing stopped before the heart stopped in most cases. More than one process may play a role in SUDEP.
How common is SUDEP?
SUDEP affects about 1 in 1,000 adults with epilepsy and about 1 in 1,000 children with epilepsy each year.
The risk of SUDEP varies. Studies report different rates depending on factors such as age, seizure type and when seizures occur.
Who is at higher risk of SUDEP?
People with tonic-clonic seizures are at higher risk of SUDEP. Risk rises as these seizures happen more often. Risk also goes up when tonic-clonic seizures aren't controlled with treatment and when they happen during sleep.
Why can SUDEP happen during sleep?
SUDEP often happens at night. The risk is higher when tonic-clonic seizures happen at night.
Seizures that happen at night may not be seen by others. If you live or sleep alone, you may have a greater risk. Researchers continue to study how sleep, reduced ability to wake up and a delay in another person noticing a seizure may play a role.
Can SUDEP be prevented?
It’s not always possible to prevent SUDEP. But reducing tonic-clonic seizures may reduce the risk. Not having tonic-clonic seizures is related to a lower risk of SUDEP.
Take antiseizure medicines as prescribed by your healthcare professional to help control seizures and lower your SUDEP risk. If seizures continue, work with your healthcare team to improve seizure control or discuss other treatment options.
If you have seizures during sleep and have a higher SUDEP risk, your healthcare team may talk with you about having supervision or monitoring while you sleep.
Seizure-detection devices can alert someone when some seizures happen. But research hasn't shown that these devices prevent SUDEP.
Treatments other than seizure medicines may help lower SUDEP risk by reducing seizures. These treatments may include epilepsy surgery and implanted devices that help control seizures.
What does a person experience during SUDEP?
It isn't clear what a person experiences during SUDEP. Many aspects of SUDEP aren't yet known.
SUDEP often isn't seen by others. Very few SUDEP events have been recorded with detailed monitoring.
What should people with epilepsy discuss with their healthcare team?
Ask your healthcare team about your SUDEP risk. This may be especially important if you have tonic-clonic seizures, seizures during sleep or seizures that keep happening despite treatment.
Talk with your healthcare team about treatment changes that may help with seizure control and whether supervision or monitoring while you sleep may be right for you.
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