Prevalence and risk factors of epileptic seizures in Alzheimer’s-disease

Abstract

Introduction Evidence suggests that patients with Alzheimer’s disease (AD) have a higher chance to have epileptic seizures. However, only a few studies observed the risk factors for developing seizures and the semiology of seizures. The aim of our study was to examine AD patients using long-term EEG recording, to identify the prevalence, main features and the risk factors of epileptic seizures. Methods We selected 42 patients meeting the criteria for probable AD. The patients underwent rigorous clinical investigation including long-term (24 h) EEG monitoring. Epileptological data were collected by retro- and prospective analysis as well. Results We identified epileptic seizures in 24% of AD patients. 72% of seizures were complex temporal seizures and in 55% without convulsion. Early onset of cognitive decline, long duration of dementia, severe stage of the disease and high number of educational years were correlated positively to the incidence of epileptic seizures. Conclusion Epilepsy is a common comorbidity of AD. Epileptic seizures predominantly occur in highly educated AD patients with early onset dementia at the severe stage of the disease. Since the most frequent seizure type is the non-convulsive complex temporal seizure, application of long-term EEG is essential in prevalence studies. Antiepileptic treatment might represent a promising future target in AD.