SUDEP – Sudden Unexpected Death in Epilepsy

Sudden Unexpected Death in Epilepsy (SUDEP) is a non-accidental death in a person with epilepsy, who was otherwise in a usual state of health. On autopsy, no other cause of death can be found. The death should not be due to status epilepticus, which is a prolonged life-threatening seizure episode.

SUDEP is now recognized as the leading cause of mortality associated with epilepsy.

The below graph puts into perspective how serious SUDEP is.  The 2nd graph shows Years of Life Lost – SUDEP is 2nd behind stroke for number of years of life lost. That highlights the fact that many young people are dying from SUDEP.

“In Figure 2A, using the U.S. population as an example, we compared our estimate of the number of SUDEP deaths with the numbers of deaths reported for other selected underlying neurologic conditions in 2010. As illustrated in this figure, the numbers of SUDEP deaths in comparison are far smaller than deaths reported for Alzheimer’s disease, stroke, and even Parkinson’s disease. However, when we examined the years of potential life lost for these conditions, the relative burden from SUDEP assumes much greater importance, second only to stroke. In 2010, we estimated there were 100,510 years of potential life lost in the United States due to SUDEP.



How common is SUDEP?

The rate of SUDEP is approximately one death per 1,000 people with epilepsy per year. However, in people with frequent epileptic seizures that are poorly controlled with medications, the rate is approximately 1 in 150 per year. Furthermore, SUDEP is the leading cause of death in young people with uncontrolled epilepsy. People with only absence or myoclonic seizures are not known to have increased risk for sudden death. These rates are inaccurate due to poor identification, lack of awareness, and inconsistencies in the investigation and recording of the deaths. The rate could be as high as 1 in 100.

What causes SUDEP?

No one knows what causes SUDEP. It is unlikely that a single cause will explain all SUDEP deaths. Most cases occur at night or during sleep and are not witnessed, leaving many questions unanswered. There is often but not always evidence of a seizure before death. Whereas a seizure is not a requirement for SUDEP to be diagnosed, studies suggest the deaths are likely seizure-related.

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

Breathing: A seizure may cause a person to briefly stop breathing (apnea). If these pauses last too long, they can reduce the oxygen delivery to the heart and the brain, and they may be life-threatening. In addition, a person’s airway may sometimes become obstructed during a convulsive seizure, leading to suffocation.

Heart Rhythm: Rarely, a seizure may cause a dangerous heart rhythm or cardiac arrest.

Brain Function: Seizures may suppress the function of vital brainstem centers, so that respiration and heart rate may temporarily malfunction.

Others: SUDEP may result from more than one cause, or from a combination of breathing difficulty, abnormal heart rhythm and suppressed brain function. Or, it may result from factors researchers have yet to discover.

Who is at risk for SUDEP?

The greatest risk factor for SUDEP is frequent seizures, especially generalized tonic-clonic (grand mal) seizures.

Other risk factors being investigated include:

• Early age of epilepsy onset or long duration of epilepsy

• Not taking medications as prescribed

• Stopping or changing medications abruptly

• Young adult age (20-40 years old)

• Intellectual disability (IQ<70)

Information taken from: and

For more information about SUDEP, please visit:

Continuing the Global Conversation: SUDEP

University of Iowa magazine – a great read about SUDEP

SUDEP Action


North American SUDEP Registry

Partners Against Mortality in Epilepsy

SUDEP Institute