Abstract found on PubMed
Objective: Existing data suggest that outcome of epilepsy presenting in the first few years of life carries a worse prognosis than later onset. However, studies are few and methods differ making interpretations of data uncertain. This study analyses outcome at age 7 and potential prognostic factors in a well characterized population-based cohort with epilepsy onset during the first 2 years of life.
Methods: An incidence cohort of 116 prospectively identified cases of epilepsy with seizure onset before age 2 years was described in a previous publication. Cases were originally retrieved from the Stockholm Incidence Registry of Epilepsy (SIRE), that registered all cases with a first unprovoked epileptic seizure from September 1, 2001 in Northern Stockholm. Data on treatment and outcome at age 7 years were collected from electronic medical records and through interviews with parents. Outcome and potential prognostic factors were analyzed with descriptive statistics and multivariable log binomial regression analysis.
Results: Eleven children (9.5%) died before age 7. Polytherapy was common. Epilepsy surgery was performed in two children. At age 7 years 61/116 (53%) children had been seizure free for the last 2 years or longer. Intellectual disability was diagnosed in 57/116 (49%) children, autism spectrum disorder in 13 (11%) and 38 (33%) children had cerebral palsy. West syndrome had a similar seizure remission rate but a worse cognitive outcome. There was no difference in outcome between first and second year onset. Six predictors, including etiology, remained associated to two or more outcome variables after regression analysis.
Significance: About half of children with infantile-onset epilepsy will become seizure free and half of them will have intellectual disability. Etiology was confirmed as a major independent predictor of outcome. Our study contributes to a more firm knowledge-base when counselling parents of infants diagnosed with epilepsy.