Prognostic factors of convulsive disorders in the first year of life.

Prognostic factors for mental and physical development and seizure control were investigated in 194 patients with convulsive disorders in the first year of life, excluding infantile spasms, neonatal convulsions and occasional convulsions. Thirty-three patients with febrile convulsions were included in the study. All patients were followed up to age six or older. The cases were subdivided into five etiologic groups; prenatal, perinatal, postnatal, doubtful and cryptogenic. Those with delayed development before the onset of seizures, or neurological abnormalities at the first visit had significantly less chance of being seizure-free and attaining normal mental and physical development. The prognosis for seizures and mental and physical development was much better in the patients with brief, symmetric, generalized tonic and/or clonic convulsions. This was also true with cryptogenic cases. There was a significant correlation between the initial EEGs and the long-term prognosis for mental and physical development and seizure control. Normal EEG was associated with a good prognosis. From these data, the neurodevelopmental status before the onset, the clinical features of convulsions and EEG findings in the infantile period were demonstrated to be important prognostic factors in addition to etiology.