title: Is long-term electroencephalogram more appropriate than standard electroencephalogram in the elderly?
abstract: OBJECTIVE
  To compare the diagnostic accuracy of standard (st) and long-term video (lt) EEG in elderly patients with suspected non-convulsive seizures.
  
  
  METHODS
  Over a 12-month period, we prospectively included all elderly (over-65) hospitalized patients having undergone lt-EEG for suspected non-convulsive seizures (n=43). st-EEG was defined as the first 20min of each lt-EEG. We recorded the patients' clinical and imaging characteristics and final diagnosis and assessed the respective diagnostic values of st-EEG and lt-EEG.
  
  
  RESULTS
  Epileptiform discharges were detected on standard EEG in only 7% of patients and in 28% of patients on Lt-EEG (p=0.004). Non-convulsive seizures were recorded in 1 case vs. 4, respectively. Nine of 40 negative standard EEG showed later epileptiform activities. The median time to occurrence of the first epileptiform activities was 46.5min (interquartile range: 36.5-239.75min). Epileptiform activity occurred during sleep only in 33% patients with a negative st-EEG. Dementia was associated with a positive lt-EEG (p:0.047).
  
  
  CONCLUSIONS
  Lt-EEG was clearly superior to standard EEG for detecting epileptiform activity in elderly when suspecting non convulsive seizures.
  
  
  CONCLUSIONS
  St-EEG has a low diagnostic yield in elderly patients with suspected non-convulsive seizures and so lt-EEG is preferable in this situation.
authors.affiliation: Epilepsy Unit, Lille University Hospital, Lille, France. Electronic address: maxime.chochoi@chru-lille.fr.
authors.forename: M
authors.initials: M
authors.lastname: Chochoi
authors.affiliation: Epilepsy Unit, Lille University Hospital, Lille, France. Electronic address: louise_tyvaert@hotmail.com.
authors.forename: L
authors.initials: L
authors.lastname: Tyvaert
authors.affiliation: Epilepsy Unit, Lille University Hospital, Lille, France; INSERM U1171, Univ. Lille, F-59000 Lille, France. Electronic address: philippe.derambure@chru-lille.fr.
authors.forename: P
authors.initials: P
authors.lastname: Derambure
authors.affiliation: Epilepsy Unit, Lille University Hospital, Lille, France; INSERM U1171, Univ. Lille, F-59000 Lille, France. Electronic address: william.szurhaj@chru-lille.fr.
authors.forename: W
authors.initials: W
authors.lastname: Szurhaj
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004569:Electroencephalography / Q000379:methods* / Q000639:trends*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012640:Seizures / Q000175:diagnosis* / Q000503:physiopathology*; D013997:Time Factors; D014741:Video Recording / Q000379:methods* / Q000639:trends*
keywords: All epilepsy/seizures; Elderly; Electroencephalogram; Non convulsive seizures