Cognitive disorders, dementia and epilepsy in the elderly

Cognitive and behavioral disorders can occur in epileptic subjects and can even simulate dementia in elderly patients. These cognitive disorders are often multifactorial, in relationship with: 1) the causal disease (type and course of brain lesions), 2) the clinical manifestations of epileptic seizure or post-crisis fit, function of localisation and lateralization of the lesions (psychological symptoms during or after seizures can lead to misdiagnosis. Delirium and/or cognitive disorders are attributed to dementia or confusion), 3) antiepileptic drugs, and 4) the psychosocial impact of the disease. At the opposite, epilepsy represents an unrecognized and underated complication of dementia, and specially of Alzheimer's disease. If partial seizures are predominant in old non demented subjects, generalized seizures (tonicoclonic, myoclonic...) are not rare in demented patients. The diagnosis of epilepsy and seizure typology are therefore often difficult in this population, and impose, in every case, an etiological analysis, to look after an associated pathology and to establish a therapeutic and psychosocial care, so great are the medico-social consequences of the epilepsy in these subjects.