NEW YORK — Clinical genetic testing results can affect the case management and clinical outcomes of individuals with epilepsy, according to data presented at this year's National Society of Genetic Counselors meeting.
Previous studies had suggested that about half of positive genetic testing findings from individuals with epilepsy are alterations in clinically actionable genes, indicating that genetic testing may be able to guide the clinical management of patients with epilepsy. In this case, clinically actionable genes could be genes associated with or contraindicated for certain anti-seizure medications, Ana Morales, clinical program director at Invitae, said.
At the meeting, Morales presented findings from the Epilepsy Evaluated, Interrogated, and Treated with Genetics, or ELEVIATE, consortium that examined how clinical practice in epilepsy is shaped by genetic testing results. The international team of researchers surveyed clinicians to gauge how genetic testing results affected both the management of individuals with epilepsy and those patients' outcomes. According to Morales, genetic testing results led to changes in patient management for about 50 percent of patients, with changes typically being the addition of a new medication. It also, though, often led to a decrease in the frequency of epileptic seizures patients experienced, which could lead to healthcare cost savings.
"We found that genetic testing can enable critical planning for management changes that improve patient outcomes in epilepsy," Morales said.
In all, Morales and her colleagues surveyed 1,567 clinicians between May and November 2020 from the US, Australia, Chile, Mexico, Ukraine, and elsewhere. Of those, 170 clinicians responded fully to the survey and provided information on 429 patients who had been found to have a pathogenic or likely pathogenic variant in an epilepsy-related gene. About half the patients were female and 53 percent were white.
In half of the cases, a genetic diagnosis of epilepsy led to a change in patients' clinical management, the researchers found. Further, for more than 80 percent of those cases, clinicians made the management changes within three months of receiving genetic testing results.
Most commonly, that change was the addition of a new medication to the patients' regimen, but referrals to a specialist or additional monitoring also occurred.
Morales noted that for 43 percent of cases, genetic testing did not lead to a change in clinical management. There, the clinician respondents most commonly said no changes were made because that patients' treatment was already consistent with the genetic diagnosis or that the test results were not informative.
When changes were made, they often affected patient outcomes, Morales said. Follow-up information was available for 172 patients who had changes to their clinical management, and the clinicians surveyed reported positive outcomes for 75 percent of the patients following those changes.
For many — 65 percent of cases — there was a reduction in the number of, or even the elimination of, seizures. As Morales noted, prior to changes in clinical management, 64 patients experienced daily seizures, but after those changes were implemented, about a quarter of those patients then had no seizures, while another quarter had annual or monthly seizures. This, she added, is a substantial improvement. This pattern of decreased seizures further held across groups with different starting frequencies of seizures.
Additionally, when they stratified their data by age, the researchers noted similar improvement in the number of seizures among both pediatric and adult patients.
Other positive outcomes included improvement in behavior or developmental issues or decreased drug side effects.
The findings suggested to Morales that genetic testing for seizures could not only lead to clinical management changes and better outcomes for patients but could also potentially lower healthcare costs by leading to better seizure management. She noted that a previous study found that poor seizure management was associated with costs of about $23,000 a year versus $14,000 a year for good seizure management, with the differences due to decreased hospitalization and visits to hospital emergency departments.
"We also believe that this data can help inform updates to existing guidelines so that genetic testing can be included as a tool that can help improve health outcomes and ultimately, hopefully, also have demonstrated reduction in healthcare costs," Morales said.