Sudden Unexpected Death In Epilepsy (SUDEP) is a category of deaths in individuals with epilepsy without a clearly defined cause. The widely accepted definition of SUDEP established by Nashef in 1997 is “the sudden, unexpected, witnessed or unwitnessed, non-traumatic, and non-drowning death of patients with epilepsy with or without evidence of a seizure, excluding documented status epilepticus, and in whom post-mortem examination does not reveal a structural or toxicological cause for death.”

The risk of SUDEP for an individual with epilepsy is more than 1 in 1,000 per year. However, it occurs more frequently in people with epilepsy whose seizures are uncontrolled. One out of 150 people with poorly controlled epilepsy may die from SUDEP each year. Most importantly, SUDEP is the leading cause of death in young people with certain types of uncontrolled epilepsy.


The greatest risk factor for SUDEP is frequent seizures, especially generalized tonic-clonic (grand mal) seizures. Other risk factors being looked at include:

  • Epilepsy beginning at an early age
  • Having epilepsy for a long time
  • Not taking medications regularly or as prescribed
  • Stopping or changing medications suddenly
  • Young adult age (20-40 years old)
  • Intellectual disability (IQ<70)

Some studies have shown that people taking a greater number of seizure medications may have a higher risk for SUDEP.

  • Yet, people may be taking multiple medications because they have a severe form of epilepsy. The epilepsy may be the problem rather than the number of medicines.
  • Studies that have looked at seizure frequency have not found an increased risk of SUDEP due only to taking many seizure medications.


What Causes SUDEP?
No one knows what causes SUDEP, but many areas are being looked at. SUDEP occurs most often at night or during sleep and the death is not witnessed, leaving many questions unanswered. There may be evidence that a person had a seizure before dying, but this isn’t always the case.

Current research into the possible causes of SUDEP focuses on problems with breathing, heart rhythm and brain function that occur with a seizure.


Can SUDEP Be Prevented?
Until further answers are available, the best way to prevent SUDEP is to lower your risk by controlling seizures. Some safety precautions can minimize the chances of SUDEP, including patients taking medications prescribed to them as well as making regular visits to their doctor, especially if the convulsive seizures are not completely controlled.


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For more information about SUDEP, please visit the Epilepsy Foundation of America’s website by clicking here.

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