Sudden unexpected death associated with seizures: analysis of 66 cases.

We have analyzed 66 cases of sudden unexpected death (SUD) in persons with seizure disorders, which were examined by the Office of the Medical Examiner, Cook County (Chicago), Illinois. The individuals ranged in age from 10 months to 60 years (mean age, 28 years). Autopsy findings were insufficient to explain death, and there was no evidence of major systemic pathology. Approximately 40% of victims were found dead in bed, and the remainder in some other room at home, apparently having been engaged in normal activity. Several died in an emergency room following a seizure at home. Cardiopulmonary resuscitation was attempted but was ineffective. Neuropathological examination revealed brain lesions, which probably caused the seizures, in 60% of the cases. In 68% the anticonvulsant blood level was subtherapeutic or below detectable levels. The prevalence of seizure-associated SUD may be between 1:525 and 1:2,100 among epileptics. The mechanism of death in these cases probably involves cardiac arrhythmias mediated by sympathetic autonomic events occurring during the seizure.