Individuals with epilepsy who sleep on their stomachs could have an increased risk of sudden death.

The findings could also have implications for sudden infant death syndrome, which is believed to be caused by seizures, the American Academy of Neurology reported.

"Sudden unexpected death is the main cause of death in uncontrolled epilepsy and usually occurs unwitnessed during sleep," said study author Dr. James Tao of the University of Chicago in Illinois, who is a member of the American Academy of Neurology.

To make their findings the researchers looked at a total of 25 studies that included 253 sudden unexpected death cases where body position was recorded. The results showed 73 percent of the cases died while sleeping on their stomach compared to 27 percent that died in other sleep positions. Additionally, the researchers found people younger than 40 were four times more likely to die while sleeping on their stomachs. Eighty-six percent of people less than 40 were found sleeping on their stomachs at time of death compared with 60 percent in those more than 40.

"We're not sure why this was more common in younger people," Tao said. "It may be that they are more likely to be single and not have anyone with them during a seizure while sleeping."

The researchers said a person sleeping with someone who suffers a generalized tonic clonic seizure while sleeping on their stomach should turn them over onto their side either during or directly following the event.

"Our findings highlight an important strategy for preventing sudden unexpected death in epilepsy-that 'back is best,'" Tao said. "Using wrist watches and bed alarms designed to detect seizures during sleep may also help prevent these deaths."

The findings were published in a recent edition of the journal Neurology.