Prognostic factors in patients with refractory idiopathic generalized epilepsy.

OBJECTIVE: Idiopathic generalized epilepsy (IGE) is an epileptic condition with good response to antiepileptic drugs (AED). Major syndromes are epilepsy with generalized tonic-clonic seizures (GTCS) alone, absence epilepsy and juvenile myoclonic epilepsy. However, clinical practice shows drug-resistant patients. Endpoint is to identify clinical features related with refractoriness in IGE and in its each individual syndrome.

METHODS: We retrospectively collected 279 consecutive patients with IGE assessed in the Epilepsy Clinic of our institution. We defined drug-resistant epilepsy as a failure of adequate trials of 2 tolerated and appropriately chosen and used AED schedules. We classified patients in two groups: drug-resistant and drug-responsive. Clinical features were compared among these groups, in the whole IGE group as well as in each syndrome.

RESULTS: There were 122 drug-resistant, 105 drug- responsive; 52 were undefined and excluded from the analysis. After multivariate analysis, early seizures onset (age <13), long-time epilepsy, several generalized seizure types, status epilepticus, EEG with generalized epileptiform activity, mainly polyspikes, and side effects with AED brought up as poor outcome factors. Additionally, 50.6% identified modifiable seizure triggers. Regarding syndromes, epilepsy with generalized tonic-clonic seizures alone had the same factors except several seizure types; presence of additional GTCS, polyspikes, history of AED side effects and psychiatric disorder were poor factors for absence epilepsy; only psychiatric comorbidity revealed significance in juvenile myoclonic epilepsy.

SIGNIFICANCE: Refractoriness in IGE and its major syndromes is associated with clinical and electrographic parameters. Moreover, lifestyle advices from neurologists to the patients might help them to achieve a better seizure control.