Utilization and yield of EEG in the elderly population

• Published in: Journal of clinical neurophysiology Vol. 22; no. 4; p. 253
• Main Authors: Widdess-Walsh, Peter, Sweeney, Bernard J, Galvin, Roderick, McNamara, Brian
• Format: Journal Article
• Language: English
• Published: United States 01.08.2005
• Subjects: Age Factors; Aged; Aged, 80 and over; Electroencephalography - statistics & numerical data; Epilepsy - classification; Epilepsy - diagnosis; Epilepsy - physiopathology; Female; Geriatric Assessment; Humans; Male; Prospective Studies; Retrospective Studies
• ISSN: 0736-0258
• DOI: 10.1097/01.WNP.0000167932.21356.D7

The EEG is a common test ordered in the elderly population for a variety of indications such as syncope, encephalopathic states, transient unresponsive episodes, and clinical seizures. The authors analyzed the spectrum of EEG abnormalities in a series of 300 homogenous elderly patients in the southern region of Ireland who were referred for the above indications. Generalized slowing was seen in 30.7% and focal abnormalities in 9% of records. Thirteen records demonstrated focal sharp waves and one record showed generalized epileptiform discharges. Two records with seizures were identified, both with nonconvulsive status epilepticus. The incidence of ECG abnormalities was high (23%). In patients referred for syncope, the incidence of EEG epileptiform abnormalities (sharp waves) was 3%, in contrast to previous reports of 49%. In patients older than 80 years (the "old old"), EEG abnormalities were more common. The yield of the EEG for common referrals such as syncope, encephalopathy, and transient unresponsiveness is low for focal abnormalities. Electrocardiographic abnormalities were common and should be identified and treated appropriately.