Childhood Absence Epilepsy: Evolution and Prognostic Factors

Abstract

Summary:Purpose: To evaluate how diagnostic criteria influence remission rates for patients with childhood absence epilepsy (CAE) and to assess clinical and EEG parameters as predictors of outcome.Methods: One hundred nineteen patients were diagnosed with CAE, according to International League Against Epilepsy (ILAE) classification criteria. They were subsequently evaluated according to stricter diagnostic criteria. Sixty-two subjects fulfilled these criteria as group 2; 57 did not and constituted group 1. Diagnostic parameters that prevented patients of group 1 from entering group 2, and variables such as sex, familial history of generalized epilepsy, and personal history of febrile convulsions also were tested as prognostic factors for terminal remission.Results: Compared with those in group 1, patients of group 2 had significantly higher rates of seizure control (95% vs. 77%), higher rates of terminal remission (82% vs. 51%), fewer generalized tonic-clonic seizures (8% vs. 30%), and shorter mean periods of treatment (2.2 vs. 3.8 years). Significantly fewer patients were receiving polytherapy in group 2 than in group 1 (11% vs. 47%), and fewer patients had seizure relapses at antiepileptic drug discontinuation (0 vs. 22%).Conclusions: Remission rates of patients with CAE are greatly influenced by the classification criteria used for selection. Stricter diagnostic criteria allow the definition of a homogeneous group of patients with excellent prognosis. Factors predicting unfavorable prognosis were generalized tonic-clonic seizures in the active stage of absences, myoclonic jerks, eyelid myoclonia or perioral myoclonia, and EEG features atypical for CAE.

Refractory absence seizures: An Italian multicenter retrospective study

“…6 Grosso et al demonstrated the strong influence of inclusion criteria on the outcome. 5 They classified patients with CAE into two groups, the first based on the ILAE classification 13 and the second on more strict criteria proposed by Loiseau & Panayiotopoulos. 2 The second group showed a higher rate of terminal remission defined as !…”

Temporal current-source of spikes suggests initial treatment failure in childhood absence epilepsy

“…Because these syndromes have relatively poor prognosis compared with CAE [40], their inaccurate categorization as CAE may lead to misrepresentation of the prognosis for CAE in clinical studies. Several studies using ILAE criteria reported the remission rate of CAE to be 50-60% [40][41][42]. To overcome these issues, we used stricter criteria than the ILAE ones to diagnose CAE in this study.…”

“…Because of the relative laxity of the ILAE criteria, various types of generalized epilepsy syndromes with frequent absence seizures could be regarded as CAE [40]. Because these syndromes have relatively poor prognosis compared with CAE [40], their inaccurate categorization as CAE may lead to misrepresentation of the prognosis for CAE in clinical studies. Several studies using ILAE criteria reported the remission rate of CAE to be 50-60% [40][41][42].…”

“…The stricter criteria were proposed by Panayiotopoulos and reviewed by Loiseau et al [23]. Grosso et al applied the stricter criteria and revealed a higher remission rate of CAE (82%) compared with studies that applied the ILAE criteria [40]. We also applied the stricter criteria for diagnosis of CAE in this study and observed results similar to Grosso's study, i.e., 88% of the CAE patients enrolled in our study were seizure-free for over 1 year.…”

Predicting antiepileptic drug response in children with epilepsy

“…In childhood absence epilepsy, applying strict diagnostic criteria [29], 95% entered remission [30], while in juvenile absence epilepsy only 44% (8 out of 17) of seizures were controlled after the mean 6-year duration of follow-up [31]. Of patients with juvenile myoclonic epilepsy, 44-74% become seizure free on drug treatment [32][33][34].…”