NEW ORLEANS – In hopeful news for people with epilepsy, those at high risk for sudden unexpected death in epilepsy (SUDEP) may move to a lower-risk category over time while those at low risk tend to stay there, suggests first-of-its-kind research being presented at the American Epilepsy Society Annual Meeting.
The study is based on a database of more than 1.4 million seizures reported by 12,402 people with epilepsy using an electronic seizure diary, SeizureTracker.com. Results of the study suggest people with epilepsy who are at high risk for SUDEP and the doctors who treat them shouldn't assume they will remain at that risk level, and that a yearly risk assessment is a good idea. Further, those at low risk can be comforted by knowing their risk is unlikely to change, researchers noted.
Every year 1 in 1,000 adults and 1 in 4,500 children with epilepsy die from SUDEP, in which a person who is otherwise healthy dies suddenly of no known cause. Previous research found SUDEP is more likely to occur in people who have generalized tonic-clonic seizures, or GTCs (formerly called grand mal seizures), which involve the whole body shaking and loss of consciousness. Based on prior studies, people who have three or more of these GTC seizures a year are considered at high risk for SUDEP, those who have one to two a year are at medium risk and those who have none are at low risk.
"While studies for eliminating SUDEP are ongoing, this research shows that an individual's risk is not set in stone," said Neishay Ayub, M.D., lead author of the study and clinical fellow at Massachusetts General Hospital, Boston. "Our findings support the recommendation that for people with epilepsy who have ongoing GTCs, the goal of treatment is to reduce GTCs and thereby, lower SUDEP risk."
To study if the risk of SUDEP can change, researchers analyzed the database from SeizureTracker.com – one of the largest groups of patient-reported seizure diaries – and found that after three years, 27 percent of patients at high risk moved out of the high-risk category. In the medium-risk group, 32.5 percent changed categories, although the analysis didn't determine if they moved to the high- or low-risk category. Of those in the low-risk category, only 7 percent moved to a higher-risk category.
Seizure Tracker is a free service that allows people with epilepsy to record their seizures using a mobile application, website or voice controls. They can enter information about their seizures during or after the seizure and share the information with their doctors if they choose. The data in Seizure Tracker are available for study purposes, but personal information that would identify a patient is private and not available to researchers.
"The next step would be to see if we can confirm this patient-reported data with an objective study to determine when seizures did or did not occur," said Daniel Goldenholz, M.D., Ph.D., M.H.Sc., senior author of the study and an instructor at Beth Israel Deaconess Medical Center, Boston. "For example, assessing information using new Food and Drug Administration-approved wearable seizure tracker devices could give us a more comprehensive picture."