SUDEP is estimated to occur in about 1 in 1,000 people with epilepsy each year.
According to the National Center for Chronic Disease Prevention and Health Promotion, sudden unexpected death in epilepsy (SUDEP) is when someone with epilepsy dies in a manner that is not caused by injury, drowning or other known causes.
It is assumed that most - though not all - cases of SUDEP take place either during or immediately after a seizure.
One cause of SUDEP could be apnea - pauses in breathing that people with epilepsy may experience during a seizure. Pauses that last too long may reduce the oxygen in the blood, which could endanger life.
Equally, during a convulsive seizure, a person's airway may become obstructed, which can lead to suffocation.
Seizures can also affect heart rhythm, which could bring on a heart attack. Alternatively, SUDEP could be caused by a combination of breathing difficulty and abnormal hearth rhythm.
SUDEP is estimated to occur in about 1 in 1,000 people with epilepsy each year. Despite it being fairly uncommon, a study by Dr. David Thurman and colleagues in the journal Epilepsia calculates that when "comparing years of potential life lost from SUDEP with selected other neurologic diseases, SUDEP ranks second only to stroke."
Lead author of another SUDEP study in Epilepsia, Dr. Barbara Kroner, an epidemiologist with RTI International in Rockville, Maryland, says:
"When someone with epilepsy dies suddenly we want to understand why. Our research calls attention to SUDEP and provides important knowledge to help neurologists have open discussions with patients, especially those at greatest risk of epilepsy-related death."
Kroner's team surveyed nearly 1,400 patients with epilepsy and more than 600 caregivers. The surveys were conducted either over the Internet or in a clinical setting, and included questions about types of seizure, epilepsy treatment, fear of death and familiarity with SUDEP.
Caregivers more aware of SUDEP than patients
The researchers found that people caring for epilepsy patients were more likely to have heard about SUDEP than their patients - 76% of caregiver respondents had heard of SUDEP compared with just 65% of patient respondents.
Respondents who were aware of SUDEP were also more likely to have an increased education level, have been exposed to severe epilepsy over a long duration, and have an epilepsy specialist as their primary care provider.
When epilepsy patients first learned about SUDEP, they reported feeling fear, anxiety and sadness. Also, knowledge of SUDEP was seen - along with increase in epilepsy severity - to escalate the concern of death among patients and caregivers. Half of respondents believed that knowledge of SUDEP would influence their management of epilepsy.
"Preventing seizures in patients with difficult to treat epilepsy may help avert sudden death," concludes Dr. Kroner. "It's important for the neurological community to continue to focus our attention on SUDEP, determining which epilepsy patients are at greatest risk and how best to educate them and their caregivers."