Abstracts

Rationale: Rational: Generalized epilepsy has a prevalence of 2.1 per 1,000 people. In our epilepsy clinic generalized epilepsy represents 43% of patients. Although the seizure outcome of a large proportion of patients with generalized epilepsy is adequate, up to 30 percent of patients become intractable to medical treatment. Patients with generalized epilepsy and drug resistant epilepsy (DRE) represent a therapeutic challenge for the epileptologist. Most studies exploring risk factors for DRE have been done in pediatric population and the majority of them combine patients with generalized and focal epilepsy. To our knowledge, no study to date has assessed risk factors of DRE in an adult population with generalized epilepsy. Methods: Methods: We performed a case-control study nested within a cohort of 117 adult patients with diagnosis of generalized epilepsy. Patients were diagnosed and classified according to the criteria of the International League Against Epilepsy ( ILAE). To define DRE we used the 2010 definition of the ILAE. We gathered from the chart the following information: demographic characteristics, characteristics of the epilepsy, treatment, diagnostic tests and risk factors for DRE. We calculated ORs and its confidence interval. We also applied a logistic regression analysis of the most significant risk factors.Results: Results: Forty three (37%) patients fulfill the definition of DRE (cases) and seventy four (63%) patients were not intractable (controls). Cases of DRE were significantly younger than controls at the onset of epilepsy (6.5 vs. 18.8 p= <0.001). In the univariate analysis we found the following associations: diagnostic of epilepsy at < 12 years of age OR 11.75, CI 4.75-29.1 p <0.001, history of status epilepticus OR 15.6, CI 3.3- 73.4, p <0.001, presence of frequent generalize spike waves in the first EEG OR 3.2, CI 1.39-7.5, p 0.005, autism OR 5.8 9, CI 1.1-30.35, p=0.02, developmental delay OR 13.5, CI 5.3-34.4 p <0.001, cryptogenic epilepsy (syndrome) OR 10, CI 3.7-26.8, p <0.001, and symptomatic epilepsy OR 8.2, CI 1.66- 41, p 0.003. In the multivariate analysis the most important predictors were status epilepticus OR, CI 13.5, p 0.041 and the presences of any epileptic syndrome (such as Lenox Gastaut syndrome) OR, CI 15.4, p 0.001.Conclusions: Conclusions: Few studies have assessed risk factors for DRE in patients with generalized epilepsy. The risk factors identified in our study are similar to the ones found in pediatric populations, although our study displays a specific profile for adult patients with generalized epilepsy. These results will help adult epileptologist to identify patients that would develop drug resistant epilepsy.