Initiating antiepilepsy treatment: An update of expert consensus in Spain

Abstract

Following publication in 2014 of the International League Against Epilepsy (ILAE) official report changing the definition of epilepsy, a number of questions remain unresolved in regard to deciding when to start treatment and to the choice of a particular antiseizure medication (ASM). This study uses a Delphi method to update consensus among a panel of experts on the initiation of epilepsy treatment in order to provide insight regarding those questions. The study was undertaken in four phases. Firstly, a multi-center steering committee met to review relevant bibliography and to draft a questionnaire. Secondly, a panel of neurologists specialized in epilepsy was selected and convened. Thirdly, an online survey was carried out in two rounds. Fourthly, the final results were discussed at a face-to-face meeting of the steering committee to draw conclusions. The final questionnaire focused on three independent sections: the decision to commence ASM in different clinical situations, the choice of initial monotherapy depending on the type of epilepsy and the patient's age/sex (including childbearing potential), and the choice of initial monotherapy depending on comorbidity. In these two latter sections, fourteen ASMs approved for monotherapy use by the EMA and available in Spain were considered. Regarding the decision as to when to commence treatment, the results show agreement exists to initiate treatment following a first generalized tonic-clonic seizure or a focal seizure if the electroencephalography (EEG) reveals epileptiform activity, if the MRI reveals a lesion, or when it occurs in elderly patients. With respect to the choice of initial monotherapy depending on the type of epilepsy and the patient's age/sex profile, it is agreed to avoid valproic acid (VPA) in women with childbearing potential, with levetiracetam (LEV) and lamotrigine (LTG) being the preferable options in generalized epilepsy. In focal epilepsy, the options are broader, particularly in men, and include the most recent ASMs approved for monotherapy. In the elderly, LEV, lacosamide (LCM), eslicarbazepine acetate (ESL) and LTG are considered the most suitable drugs for initiating treatment. With regard to comorbidities, the recommendation is to avoid enzyme inducing ASMs, with LEV, the most recent ASMs approved for monotherapy and LTG being the preferred options. In conclusion, as the ILAE definition states, there are different situations that lead to treatment initiation after a first seizure. When choosing the first ASM, the type of epilepsy, childbearing potential and drug-drug interaction are key factors.

Keywords: Antiepileptic drugs; Antiseizure medications; Comorbidities; Consensus; Epilepsy; Initiation of treatment.