What causes SUDEP?

The precise mechanism, or cause, of death is, as yet, not understood.  Most sudden deaths of people with epilepsy are unwitnessed and this makes it difficult to determine what, exactly, occurs in the last moments of life.  By definition, the post mortem does not reveal a cause of death suggesting that the terminal event is due to disturbance of function, not structure.  Most frequently, but not always, there is evidence for seizure activity prior to death and r
ecent studies strongly support a close relationship between seizure episodes (especially generalized convulsions) and SUDEP.

Various potential mechanisms have been proposed and these mainly involve the cardiac and/or respiratory systems.  It is unknown whether mechanisms are jointly or severally responsible, what leads to the fatal cardiac event and/or the cessation of breathing, what role the brain and/or seizure plays in the whole process or, indeed, whether the same events trigger SUDEP in each person.

Next: Risk factors for SUDEP