Abstract
Background: It is important to predict as soon as possible after diagnosis and starting treatment, the likely clinical course of childhood-onset epilepsy, both in terms of seizure control and even more pertinently, seizure intractability. Little is known about the factors predictive of seizure control in African children.
Methods: All consecutive cases of newly-diagnosed childhood epilepsy seen over a period of two years in the Paediatric Neurology clinic, University College Hospital, Ibadan, Nigeria were prospectively followed for a period of three years to determine seizure outcomes. Remission was defined as being seizure-free for at least two consecutive years.
Results: A total of 170 children were enrolled but 54 defaulted and were excluded from further analysis. Twenty nine (25%) attained remission while 20 (17.2%) showed signs of intractability. The remaining 67 (57.8%) showed some response to anti-epileptic drug (AED) therapy. Primary generalized epilepsy was found to be significantly associated with seizure remission and successful discontinuation of AED. Factors associated with reduced likelihood of seizure remission were remote symptomatic/cryptogenic aetiology, slow waves on electroencephalography (EEG), high seizure frequency of at least one attack/month at presentation, failure of response to the initial AED and presence of associated neurological deficits. On logistic regression, high seizure frequency and presence of slow waves on EEG remained independent negative predictors of seizure remission.
Conclusion: About one-quarter of Nigerian children with newly diagnosed epilepsy attain early seizure remission within the first three years of AED therapy. The major predictors of poor seizure control and failure of seizure remission include high seizure frequency at presentation and presence of slow waves on EEG.
Keywords: Predictors, seizure remission, childhood, epilepsy
Résumé
C’est important de prédire de façon précise après le diagnostic et la fin du traitement, la durée des symptômes cliniques du début de l’épilepsie à l’enfance inclut le contrôle des crampes et plus pertinent l’intraçabilité des crampes. Très peu est connu des facteurs précurseurs des crampes aux enfants en Africain. Tous les cas consécutif des nouveaux cas diagnostiques d’épilepsie en enfance vu durant une période de deux ans en Clinique pédiatrique et neurologique du Centre Hospitalier Universitaire d’Ibadan, Nigeria étaient suivi pour une période de trois ans et les résultats des crampes déterminés. La rémission était définie comme étant la période sans crampes pour une période de deux ans consécutif. Au total 170 enfants étaient recrutés mais 54 échoués et étaient exclus des analyses. Trente neuf (25%) atteignaient la rémission tandis que 20 (17.2%) démontraient des signes intracables. L’épilepsie primaire généralisée était observé étant significativement associée avec les crampes de rémission et l’arrêt des médicaments antiépileptiques. Les facteurs associés avec la rémission des crampes a l’enfance étaient l’étiologie distant symptomatique/cryptogénique des ondes faibles sur l’électroencéphalographie (EEG), fréquence des crampes élevée au moins une attaque /mois a la présentation, l’échec de répondre initialement aux médicaments et la présence associé des déficits neurologiques. En utilisant la régression, la fréquence des crampes élevée et la présence des ondes sur l’EEG
restaient des facteurs indépendants négatifs de la rémission des crampes. Environ un quart des enfants Nigérian ayant des cas d’épilepsie nouvellement diagnostiqués ont eu des remissions de crampes dans les trios premières années de l’usage des médicaments antiépileptiques. Les facteurs majeurs de contrôle des crampes et l’échec de la rémission des crampes incluent la fréquence des crampes élevées la présentation et la présence des ondes faibles sur l’EEG.
Correspondence: Dr. I.A. Lagunju, Department of Paediatrics, University College Hospital, Ibadan, Nigeria. E-mail: ilagunju@yahoo.co.uk
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