Medline ® Abstracts for References 3,4

Sudden unexpected death in epilepsy (SUDEP) is a category of death in people with epilepsy occurring in the absence of a known structural cause of death and is most likely heterogeneous with regard to mechanisms and circumstances. SUDEP is particularly difficult to investigate in research studies for several reasons, including its relatively low incidence, its unpredictable occurrence often in unwitnessed settings, and its low rate of complete autopsy examinations. Over the past two decades, two complementary definitions have been used in most SUDEP studies, but often with variations. We propose here a unified SUDEP definition and classification to resolve current ambiguities and to retrieve cases that would not have been further studied if the previous definitions were used. The proposed Unified SUDEP Definition and Classification contains, in addition to concepts inherent in the previous definitions, nine main recommendations. (1) The word "unexpected," and not the word "unexplained," should be uniformly used in the term SUDEP. (2) The SUDEP category should be applied when appropriate, whether or not a terminal seizure is known to have occurred. (3) The "Possible SUDEP" category should be used only for cases with competing causes of death, with cases left unclassified when data are insufficient to reasonably permit their classification. (4) Cases that would otherwise fulfill the definition of SUDEP should be designated as "SUDEP Plus" when evidence indicates that apreexisting condition, known before or after autopsy, could have contributed to the death, which otherwise is classified as SUDEP (e.g., coronary insufficiency with no evidence of myocardial infarction or long-QT syndrome with no documented primary ventricular arrhythmia leading to death). (5) To be considered SUDEP, the death should have occurred within 1 h from the onset of a known terminal event. (6) For status epilepticus as an exclusion criterion for SUDEP, the duration of seizure activity should be 30 min or more. (7) A specific category of SUDEP due to asphyxia should not be designated, the distinction being largely impractical on circumstantial or autopsy evidence, with more than one mechanism likely to be contributory in many cases. (8) Death occurring in water but without circumstantial or autopsy evidence of submersion should be classified as "Possible SUDEP." If any evidence of submersion is present, the death should not be classified as SUDEP. (9) A category of "Near-SUDEP" should be agreed to include cases in which cardiorespiratory arrest was reversed by resuscitation efforts with subsequent survival for more than 1 h. Scenarios that demonstrate the basis for each SUDEP category are described. If disagreement exists about which category fits a particular case, we suggest the use of consensus decision by a panel of informed reviewers to adjudicate the classification of the case.

OBJECTIVES: To study the circumstances of death in sudden death in epilepsy.

METHODS: Self referred bereaved relatives of patients with epilepsy who had died suddenly were interviewed with information obtained substantiated through other sources-namely, coroners' officers' reports, postmortem reports, previous medical records, and EEG reports.

RESULTS: Of 34 cases, 26 were classified as sudden unexpected deaths in epilepsy (SUDEP). Twenty four of 26 cases of SUDEP were unwitnessed. Evidence indicative or suggestive of a seizure was found in most. In 11 of 26 the position of the head was such that breathing could have been compromised. Cases included both localisation related and idiopathic primary generalised epilepsy. Only three were in remission at the time of death. Most relatives expressed the view that they would have preferred to have known that epilepsy could be fatal.

CONCLUSIONS: Although the deaths in question were largely unwitnessed, the available evidence suggested that most cases of SUDEP represented ictal or postictal seizure deaths, occurring in people with a history of generalised tonic clonic seizures, and in both primary generalised and localisation related epilepsy. These interviews highlight the needs of bereaved relatives and their sense of isolation in the face of an entirely unexpected and apparently unexplained loss.