ORLANDO, Fla. ― More than 40% of adults with epilepsy have a genetic link to their condition, according to a study presented at the American Epilepsy Society Annual Meeting. While genetic testing is common in children with epilepsy, the findings underscore that it should also be offered to adults with epilepsy who have not received it, particularly if they had their first seizure as a child.
Getting a genetic diagnosis leads to a change in care for one in five people, previous research has found. For example, they may be prescribed a different type of anti-seizure medicine or the results may alter guidance on surgical treatment or family planning.
“Genetic testing should be considered in adults with epilepsy if the cause of their condition is unknown,” said Yi Li, MD, PhD, lead author of the study and clinical assistant professor of neurology at Stanford University, Stanford, California. “Our study highlights a significant real-world delay in genetic testing of about 10 years from the first seizure. The price of genetic testing has decreased over time, so ideally, more people with epilepsy won’t have to wait until they are adults to be tested.”
For the first time, guidelines released by the National Society of Genetic Counselors earlier this year — and endorsed by the American Epilepsy Society — strongly recommend genetic testing in all patients with an unknown cause of epilepsy, regardless of their age.
Researchers identified 286 patients with epilepsy (ages 16 and older) from the Stanford Research Repository (STARR) database between Jan. 1, 2018, and June 1, 2023 who had received genetic testing. They had one of three types of tests: whole exome sequencing (WES, which includes all 20,000 genes in one test), panel testing (which looks at the genes associated with epilepsy), or microarray testing (which assesses missing sections of chromosomes). The average age for having the first seizure was about 12 years old, but 21.4% had their first seizure when they were infants.
Of the 286 patients, 117 (41%) were found to have at least one genetic variant related to epilepsy. Additionally, five (2%) had genetic variants unrelated to epilepsy and 152 (53%) had variants of uncertain significance. Patients who had a history of developmental delay and seizures at a younger age were most likely to have a positive genetic result.