title: Aetiology and prognosis of encephalopathic patterns on electroencephalogram in a general hospital.
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.
authors.affiliation: Department of Neurology, Cork University Hospital, Cork, Ireland. sosulliv@ion.ucl.ac.uk
authors.forename: S S
authors.initials: SS
authors.lastname: O'Sullivan
authors.forename: A
authors.initials: A
authors.lastname: Neligan
authors.forename: G M
authors.initials: GM
authors.lastname: Mullins
authors.forename: S
authors.initials: S
authors.lastname: Daly
authors.forename: B
authors.initials: B
authors.lastname: McNamara
authors.forename: R J
authors.initials: RJ
authors.lastname: Galvin
authors.forename: B J
authors.initials: BJ
authors.lastname: Sweeney
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001927:Brain Diseases / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D003704:Dementia; D004569:Electroencephalography; D005260:Female; D005500:Follow-Up Studies; D006769:Hospitals, General / Q000706:statistics & numerical data; D006801:Humans; D007859:Learning Disabilities / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012640:Seizures / Q000209:etiology