Long‐term seizure remission in childhood absence epilepsy: Might initial treatment matter?

Summary Objective Examine the possible association between long‐term seizure outcome in childhood absence epilepsy ( CAE ) and the initial treatment choice. Methods Children with CAE were prospectively recruited at initial diagnosis and followed in a community‐based cohort study. Children presenting with convulsive seizures, significant imaging abnormalities, or who were followed <5 years were excluded. Early outcomes included success of initial medication, early remission, and pharmacoresistance. The primary long‐term outcome was complete remission: ≥5 years both seizure free and medication free. Survival methods were used for analyses. Results The first medication was ethosuximde ( ESM ) in 41 (69%) and valproic acid ( VPA ) in 18 (31%). Initial success rates were 59% ( ESM ) and 56% ( VPA ). Early remission and pharmacoresistance were similar in each group. Apart from atypical electroencephalography (EEG) features (61% [ VPA ], 17% [ ESM ]), no clinical features varied substantially between the treatment groups. Complete remission occurred in 31 children (76%) treated with ESM and 7 (39%) who received VPA (p = 0.007). Children with versus without atypical EEG features were less likely to enter complete remission (50% vs. 71%, p = 0.03). In a Cox regression, ESM was associated with a higher rate of complete remission than VPA (hazards ratio [ HR ] 2.5, 95% confidence interval [CI] 1.1–6.0; p = 0.03). Atypical EEG features did not independently predict outcome (p = 0.15). Five‐year and 10‐year remission, regardless of continued treatment, occurred more often in children initially treated with ESM versus VPA . Significance These findings are congruent with results of studies in genetic absence models in rats and provide preliminary evidence motivating a hypothesis regarding potential disease‐modifying effects of ESM in CAE. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here .