P.102 Childhood Absence Epilepsy: Prevalence of treatment resistance and neuropsychiatric comorbidity.

Abstract

Background: Seizures in childhood absence epilepsy (CAE) are usually easily controlled with anti-seizure medications (ASMs). Factors predictive of treatment resistance remain unclear. Our objectives were to assess prevalence of neuropsychiatric problems and factors influencing refractoriness in a cohort of CAE at a single centre. Methods: We retrospectively reviewed patients with CAE (ILAE 2017 classification) diagnosed between January 1999 and December 2016 with at least 1-year follow-up. Treatment resistance was defined as failure to respond to two or more appropriate ASMs. Exclusion criteria included eyelid myoclonia with absence, myoclonic absence, and generalized tonic-clonic (GTC) seizure before developing absences. Results: The study population comprised 164 patients (65 males) 6.25-year-old on average at absence onset. 22% had treatment-resistant seizures. The first ASM was Ethosuximide in 63.4%, Valproic acid in 23.2%, and Lamotrigine in 6.7%. Statistical differences between response groups included developing a second seizure type specifically GTC, the second and third ASM, and absence of EEG normalization. At last follow-up, 43.3% of children were seizure-free off ASMs. 32.9% of children had learning disabilities, 28% ADHD, and 12.8 % anxiety. Conclusions: 22% of children with CAE had treatment-resistant seizures. Photoparoxysmal response was not predictive of treatment resistance. Neuropsychiatric problems were common with learning disabilities increased with refractory absences.