DIAGNOSTIC AND PROGNOSTIC IMPLICATIONS OF THE 1ST EPILEPTIC SEIZURE IN ADULTS

Actual epidemiological studies show a prevalence rate for active epile psy in 0.5-1 %, whereas single seizures occur in up to 5 % of the gene ral population. Assessment of the significance of first epileptic reac tion requires precise definition and classification of the episode, a careful analysis of the entire context including thorough case history , and indirect anamnesis. The value of EEG-techniques for this issue i s part of a controversial discussion. By means of cranial computerized tomography (cCT), brain tumours were detected as structural correlate in 5 to 16 % of first-seizure-patients. In recent studies, estimated risk of seizure recurrence after first unprovoked seizure ranged from 27 % to 78 %: most of the relapses were observed in the first 6 months after the first event. The wide range of relapse rates is due to the divergent methodological designs (retro- versus prospective design, se lection of patients, length of time before study entry) in the differe nt studies. There are conflicting results concerning risk factors and predictive value of the following variables: pathology in the neurosta tus, focal seizure type or Todd's paresis, history of febrile seizures , symptomatic genesis, and specific epileptic potentials and time of d ay of seizure event. In an actual metaanalysis of recent studies, seiz ure etiology and EEG were the strongest predictors of recurrence. The preliminary results of our prospektive study with a strict protocol an d first-seizure-design are presented: we observed a seizure relapse in 26.7 % of 78 adult patients (age range: 17-84 years) after a mean lat ency of 4.4 months. Until now, there is no evidence for potential pred ictors of seizure recurrence. Data are missing concerning the question of establishing early therapy in these patients: following the hypoth esis of a dynamic process in epilepsy, most authors recommend sufficie nt anticonvulsant treatment after the second non-provoked seizure to p revent development of chronic epilepsy. For a comprehensive definition of prognosis in further studies, data must be collected on the patien t's life situation including changes following the seizure event.