Aetiology and prognosis of encephalopathic patterns on electroencephalogram in a general hospital

• Published in: Journal of clinical neuroscience 2008-06, Vol.15 (6), p.637-642
• Main Authors: O’Sullivan, S.S, Neligan, A, Mullins, G.M, Daly, S, McNamara, B, Galvin, R.J, Sweeney, B.J
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Brain Diseases - diagnosis; Brain Diseases - epidemiology; Brain Diseases - physiopathology; Dementia; EEG; Electroencephalogram; Electroencephalography; Encephalopathy; Female; Follow-Up Studies; Hospitals, General - statistics & numerical data; Humans; Learning Disorders - etiology; Male; Middle Aged; Mortality; Neurology; Prognosis; Retrospective Studies; Seizures - etiology
• ISSN: 0967-5868; 1532-2653
• DOI: 10.1016/j.jocn.2007.04.004

Abstract The purpose of this study was to investigate the frequency and clinical outcome of patients with encephalopathic electroencephalograms (EEGs) in a neurophysiology department based in a general hospital. We performed a retrospective review of all EEGs obtained during an 18-month period in a large tertiary referral hospital. The referral reasons for EEG, the diagnoses reached, and patient outcomes were reviewed according to EEG severity. One hundred and twenty-three patients with encephalopathic EEGs were reviewed. The most common referral reason found was for an assessment of a possible first-onset seizure. The most common diagnosis found was one of dementia or learning disability. Of patients who were followed-up for a median of 19 months, 20.7% had died. The mortality rate generally increased according to the severity of the encephalopathy on EEG. However, 21.4% of those patients with excessive theta activity only on EEG had died. This study highlights an increased mortality even in the apparently ‘milder’ degrees of EEG abnormalities.