Sudden unexplained death in epilepsy is a mysterious, rare condition, better known as SUDEP, in which typically young or middle-aged people with epilepsy die without a clearly defined cause. By definition, (1) death is sudden and unexpected, (2) a clear cause of death must be absent, and (3) victims must have had epilepsy. Victims are often found in bed with or without signs of having had a convulsive seizure, but were otherwise in a reasonable state of health at the time of death. Although seizures are suspected to have occurred prior to death, there should be no evidence of seizure as the direct cause of death.
Although the cause of death is unknown, some researchers suggest that a seizure causes an irregularity in the heart rhythm. More recent studies have suggested that a combination of impaired breathing (apnea), increased fluid in the lungs (impairing the exchange of oxygen and carbon dioxide), and being face down on the bed all combine to cause death due to impaired respiration. In many cases, death probably occurs after a seizure has ended.
The risk of SUDEP for a person with epilepsy is about 1 in 3000 per year. The risk for people with severe, intractable epilepsy who have frequent seizures and take large doses of many antiepileptic drugs is much higher at about 1 in 300 per year. Among all patients with epilepsy, SUDEP accounts for less than 2% of deaths. The risk is highest in young male adults (ages 20-40), with frequent convulsive seizures, taking several antiepileptic medications.
SUDEP rates are highest in young people aged 20-40, and greater in men than women. Another major risk factor for SUDEP appears to relate to the severity of the epilepsy, as SUDEP is more common in people with:
On the other hand, SUDEP is rare in patients with new onset epilepsy, in patients without convulsive seizures as a seizure type, and in patients with well controlled seizures.
A few safety precautions can minimize the chances of SUDEP: