EEG after sleep deprivation in patients with suspected epilepsy

The purpose of this study was to investigate to what extent sleep deprivation provokes epileptiform discharges in EEG in patients with suspected epilepsy. Data from 189 adults and children with unspecified seizures who had had EEG after sleep deprivation were evaluated retrospectively. Previous standard EEGs were without epileptiform discharges. The patients' final diagnosis were collected from the medical records. 13% of the patients demonstrated epileptiform activity in their sleep deprivation EEG, and significantly more epileptiform activity was found in patients with generalized tonic-clonic seizures and absences. None of the patients with a history of syncope showed epileptiform activity. The activation rate was higher in patients with an abnormal standard EEG compared to those with a normal standard EEG. The sensitivity of sleep deprivation EEG in this study was 35%, specificity 98% and positive predictive value 92%. Sleep deprivation EEG seems to have greatest diagnostic value in patients with generalized tonic-clonic seizures, absences and abnormal standard EEG.