WASHINGTON, DC—Developmental delay and the presence of more than one seizure profile may be risk factors for drug resistance among adults with generalized epilepsy, according to data presented at the 67th Annual Meeting of the American Epilepsy Society. Neonatal seizures, psychiatric comorbidity, family history of epilepsy, and etiology of epilepsy also may be associated with drug-resistant epilepsy.
“To our knowledge, this is one of the few studies assessing risk factors of drug-resistant epilepsy in an adult population with generalized epilepsy,” stated Lizbeth Hernández-Ronquillo, MD, Research Coordinator of the Saskatchewan Epilepsy Program at the University of Saskatchewan in Saskatoon, Canada. “Most studies exploring risk factors for drug-resistant epilepsy have been done in pediatric populations, and the majority of them combine patients with generalized and focal epilepsy.”
Dr. Hernández-Ronquillo and her colleagues performed a case–control study of 118 adults with generalized epilepsy. Diagnosis, classification, and the definition of drug-resistant epilepsy were based on criteria from the International League Against Epilepsy. The researchers recorded patients’ sociodemographic characteristics, characteristics of epilepsy, treatment, diagnostic tests, and risk factors for drug-resistant epilepsy. Descriptive statistics enabled the investigators to assess frequencies and distributions. The study authors performed logistic regression analysis to identify the most significant risk factors.
Of the 118 patients, 71 were male. The population’s mean age at onset was approximately 14, and mean age during the study was about 33. Forty-four patients were considered to have drug-resistant epilepsy.
Bivariate analysis indicated that age at onset, cryptogenic epilepsy, status epilepticus, number of seizures per month, and number of antiepileptic drugs tried were associated with drug-resistant epilepsy. After the investigators performed logistic regression analysis, developmental delay and the presence of more than one seizure profile remained statistically significant risk factors for drug-resistant epilepsy. The researchers also identified good response to the first antiepileptic drug, idiopathic etiology, and the presence of a lesion on MRI to be protective factors against drug-resistant epilepsy.
“The risk factors identified in our study are similar to the ones identified in pediatric populations, although our study displays a specific profile for adult patients with generalized epilepsy,” reported Dr. Hernández-Ronquillo. “These results can help adult epileptologists to identify patients with generalized epilepsy who could develop drug-resistant epilepsy,” she concluded.
—Erik Greb