Neuropediatrics 2000; 31(4): 169-174
DOI: 10.1055/s-2000-7456
Original Article

Georg Thieme Verlag Stuttgart · New York

Nonconvulsive Status Epilepticus - A Possible Cause of Mental Retardation in Patients with Lennox-Gastaut Syndrome

M. Hoffmann-Riem1 , W. Diener2 , Chr. Benninger3 , D. Rating3 , K. Unnebrink4 , U. Stephani5 , H.-P. Ernst6 , R. Korinthenberg1
  • 1 Department of Neuropediatrics and Muscular Disorders, University of Freiburg, Freiburg, Germany
  • 2 Hospital for Disabled Children Schömberg, Schömberg, Germany
  • 3 Department of Child Neurology, University of Heidelberg, Heidelberg, Germany
  • 4 Department of Medical Biometry, University of Heidelberg, Heidelberg, Germany
  • 5 Department of Neuropaediatrics, University of Kiel, Kiel, Germany
  • 6 Epilepsy Center Kehl-Kork, Kehl, Germany
Further Information

Publication History

Publication Date:
31 December 2000 (online)

Lennox-Gastaut syndrome (LGS) is one of the most severe types of childhood epilepsy. It is usually resistant to treatment and associated with mental retardation. To delineate the risk factors associated with the outcome of LGS, we evaluated, in a retrospective and multicentre study, the course of the disease, EEG tracings, and intellectual function in 101 patients. Inclusion criteria were the presence of tonic seizures as well as slow spike and wave complexes in the EEG. The average documented observation period was 16 years (range 4 - 31 years). Overall, the intellectual and neurological outcome was poor. At the last follow-up, 38 % of the patients could not speak, 21 % were unable to walk and only 4 % were free of seizures. Four independent risk factors for severe mental retardation were identified by multivariate analysis. These were in a decreasing order of importance: nonconvulsive status epilepticus (NCSE), odds ratio (OR) 25.2, a previous diagnosis of West syndrome (OR 11.6), a symptomatic etiology of epilepsy (OR 9.5), and an early age at onset of epilepsy (OR 4.7). The results highlight the association between NCSE and the severity of mental retardation in patients with LGS; this association appears to be independent of symptomatic etiology. Our data provide an indirect evidence that, at least in some of the patients, NCSE is not only a concomitant feature, but also a cause of severe mental retardation.

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Prof. Dr. med. Rudolf Korinthenberg

Department of Neuropaediatrics and Muscular Disorders Paediatric University Hospital

Mathildenstr. 1

79106 Freiburg

Germany

Email: E-mail: rudokori@kkl200.ukl.uni-freiburg.de

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