A study in patients with epilepsy led by researchers at the medical genetics company Invitae shows that after genetic testing almost 50% of the patients changed their treatment and 75% reported improved outcomes as a result.
Up to 40% of children and 23% of adults with epilepsy have a genetic cause for their condition, which can impact treatment choice. But genetic testing is not currently widely carried out in epileptic patients.
To assess how useful such tests could be for improving outcomes, Dianalee McKnight, medical affairs director for rare disease at Invitae, and colleagues carried out a cross-sectional study in 418 patients with epilepsy who had genetic testing to look for causative genetic variants. The study is published in JAMA Neurology.
Patients of any age were eligible to take part, but the median age of participants was 4 years, with a range from 0-52 years. The group was 54% female and 53% White, with the rest of the group made up of individuals from a range of different ethnicities.
The genetic tests revealed diagnostic variants in 76 genes, 26 of which are known to be clinically actionable or could result in treatment changes.
Overall, genetic testing resulted in a change in clinical disease management, most commonly trialling a new medication, in 208 patients (49.8%). In the majority of cases, this happened within 3 months of the test results being released.
In 167 patients with follow-up data available, 125 (74.9%) had improved outcomes after the changes were initiated, such as reduction or elimination of their seizures and also improvement of other clinical symptoms. A small number had negative effects such as a general decline in their condition (12%), increased seizure frequency (3.6%) and adverse drug side effects (1.8%).
“This information is vital to Invitae’s mission to bring genetics into mainstream medicine to improve healthcare,” said McKnight, who is lead author of the study. “This study provides further evidence that genetic testing results can benefit the provider and the patient by guiding clinical management and improving health outcomes.”
This study is backed up by a recently published National Society of Genetic Counselors guideline document recommending genetic testing for all individuals with unexplained epilepsy.