Study Shows People with Epilepsy Take Antiepileptic Drugs for Average of Six to Eight Months

A review of long-term data of new antiepileptic drug (AED) use found that epilepsy patients refill their prescriptions for an average of six to eight months, according to results presented today by a Yale School of Medicine researcher at the American Epilepsy Society annual meeting.

These data show usage of AEDs in a real-world setting, versus data from controlled clinical trials.

“Treatment persistence is a global measure of acceptability of treatment based on efficacy, adverse events and convenience,” said Joyce Cramer, lead investigator of the study and associate research scientist in the department of psychiatry at Yale University School of Medicine. “Real-world data help us truly assess how well a therapy is working for a patient. For example, if patients are remaining on one drug longer than another, the implication is that the drug that is taken longer is helping reduce seizures with fewer side effects.”

Epilepsy is a chronic disorder that affects more than 2.3 million Americans, or one in every 100 people. People with epilepsy might try several different therapies to find a balance between reducing seizures and limiting medication side effect.

Researchers analyzed 12 months of national pharmacy chain data from 6,876 patients to establish patterns of AED usage. Persistence was defined as time from the first prescription and the last month a prescription was filled. Patients were more likely to comply with AED drugs that reduced their symptoms with few side effects.

Cramer explained that part of the reason patients refill prescriptions for less than 12 months as directed is poor compliance with the regimen. Most AEDs are prescribed as twice daily dosing, so missing doses often results in left over pills at the end of the month and can extend the time between refills.

“My previous research has shown that people take only three-fourths of their medication as prescribed,” said Cramer. “These new data confirm that compliance is an issue, while indicating that persistence rates differ among drugs. The combination of a good AED selection and good compliance are important for the successful treatment of epilepsy.”