Sudden Unexplained Death in Epilepsy (SUDEP)

RARE BUT DEADLY

BY ANDREW N. WILNER, MD, FACP, FAAN,
SPECIAL TO EPILEPSYUSA
EpilepsyUSA 2008 |Issue 2

At a recent meeting of the American Epilepsy Society, Mrs. Marilyn Jones [not her real name] told me that her twenty-two year old son had died of SUDEP (Sudden Unexplained Death in Epilepsy). With tears in her eyes, she complained that no one had ever told her about this rare and mysterious condition. If only she had known, she told me, maybe she could have done something to prevent it.

While we know that people with epilepsy are at increased risk of death due to accidents from seizures such as drowning and other causes such as status epilepticus, SUDEP is different. Researchers define SUDEP as “sudden, unexpected, witnessed or unwitnessed, nontraumatic and nondrowning deaths in patients with epilepsy, with or without evidence of a seizure and excluding documented status epilepticus, in which postmortem examination does not reveal a toxicologic or anatomic cause of death” (Nashef et al. 2007). A sudden dysfunction of the heart or lungs seems to be responsible, but we do not know what causes the dysfunction. The most important characteristics of SUDEP are summarized in Table 1.

TABLE 1. WHAT WE KNOW ABOUT SUDEP (SUDDEN UNEXPLAINED DEATH IN EPILEPSY)

• Generally uncommon.
• More common between ages 20–40 years.
• More common in people with uncontrolled seizures.
• More common in people with many years of seizures.
• Best prevented by good seizure control.

Elson So, M.D., Professor of Neurology, Director, Section of Electroencephalography, Mayo Clinic College of Medicine, Rochester, MN, cochairs the American Epilepsy Society and the Epilepsy Foundation Joint Task Force on SUDEP. “Patients who have uncontrolled and frequent seizures, especially generalized convulsions, are at greatest risk of SUDEP. Young adults from about late teens to about late 40s appear to be at higher risk than other age groups. Exactly how generalized convulsions are associated with SUDEP in some persons, whereas they are not in others, is not known.”

Dr. So counsels his patients, “For a person with epilepsy, in general, the risk is small, at one in 3,000 persons over a one-year period. For a person with poorly controlled seizures, especially generalized convulsions, the risk is one in 100 persons over one year. Persons with absence or myoclonic seizures are not known to have increased risk for SUDEP.”

Because SUDEP is generally uncommon, some doctors are reluctant to discuss the condition with their patients. As might be expected, the possibility of SUDEP is frightening, and physicians may feel that most patients are better off not knowing about it, as they are unlikely to be affected. However, Jeffrey Buchhalter, M.D., Ph.D., Director of the Comprehensive Pediatric Epilepsy Program, Phoenix Children’s Hospital, Phoenix, AZ, and a member of the Joint Task Force, routinely discusses the topic of SUDEP with his patients, “The message is that the risk is extremely low for the vast majority of children with seizure disorders. Most parents are very reassured with this information, as many were afraid to ask the question “Could my child die due to a seizure?” stated Dr. Buchhalter.

Dr. Buchhalter has had two cases of SUDEP in his practice. “Both were children, both truly unexpected, and very tragic,” observed Dr. Buchhalter.

Because many SUDEP victims are found dead in bed, it has been suggested that it may be helpful if someone capable of giving assistance shares the bedroom with the person with epilepsy. However, Dr. Buchhalter emphasized that there is no proof that constant supervision will decrease deaths due to SUDEP, “There is only one paper in the literature that suggests direct observation may be associated with decreased death during sleep. I would be very cautious about making this a recommendation as the implications for children and adults are profound.”

Dr. So has this advice for people with epilepsy concerned about SUDEP, “Strive for the best seizure control possible, and as early as possible. Consider early epilepsy surgery evaluation, if appropriate. Do not adjust your seizure medications on your own; and most importantly, do not stop medications on your own. Take medications on a regular basis as prescribed.”

Because it is generally uncommon, SUDEP is difficult to study. However, a number of researchers are investigating SUDEP to try and learn what causes it, and, of course, how to prevent it. The Joint Task Force plans to:

1. Develop a position statement regarding when and how SUDEP should be discussed with patients and caregivers.
2. Design methods by which the medical and lay communities are aware of the risk of SUDEP.
3. Provide recommendations regarding research directions in SUDEP.
4. Explore steps the organizations can make in obtaining large-scale, prospective, international, communitybased study of SUDEP in order to identify risk factors.
5. Identify possible preventive strategies for SUDEP.

Many researchers are actively trying to learn more about SUDEP. For example, at the 2007 American Epilepsy Society meeting, four scientific papers were presented regarding SUDEP (www.aesnet.org). These papers included research on SUDEP in animals, possible causes of SUDEP and the value of death certificates in identifying cases of SUDEP.

Since the death of her son, Mrs. Jones has become active in “Epilepsy Bereaved,” an organization that provides information about SUDEP for professionals and family members. People affected by SUDEP may find it helpful to contact this organization or the Epilepsy Foundation.

The writer is the author of EPILEPSY:199 ANSWERS (A DOCTOR RESPONDS TO HIS PATIENTS’ QUESTIONS).