title: Interictal spiking in adult newly-diagnosed focal epilepsy of unknown cause: The effect of age.
abstract: OBJECTIVE
  To assess the yield of interictal EEG spiking in standard and whole-night sleep EEGs in elderly subjects with recent-onset focal seizures compared to younger patients.
  
  
  METHODS
  Detection of interictal epileptiform abnormalities (IEAs) and rating of mean spike index (number of interictal discharges/minute) values for different sleep stages (NREM stages 1-2 and 3-4 and REM sleep) in standard EEG (S-EEG) and 24-h ambulatory EEG (A-EEG) at first referral in three groups of thirty consecutive outpatients [aged 20-39 (young), 40-59 (adults) and ⩾60years (elderly)], retrospectively selected according to a subsequent diagnosis of focal epilepsy of unknown cause, no sleep disorders or drugs or comorbidities affecting sleep and EEG.
  
  
  RESULTS
  Elderly subjects showed a lower rate of IEAs on S-EEG (p<0.01) but a higher propensity for spiking during deep NREM sleep, 11/30 showing IEAs exclusively during stages 3-4. Mean spike index showed a significant increase in IEAs between sleep stages 1-2 and 3-4 in the elderly subjects (p<0.001).
  
  
  CONCLUSIONS
  A significant association emerged between IEAs during deep sleep and age (p<0.001).
  
  
  CONCLUSIONS
  EEG recordings covering deep NREM sleep should be recommended when IEAs detection is needed to support a diagnosis of epilepsy in elderly subjects.
authors.affiliation: Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy; Division of Neurology, Ospedale Civile, Voghera, Pavia, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Arbasino
authors.affiliation: Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy; Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Calorio
authors.affiliation: Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy; Epilepsy Center, Clinic of Nervous System Diseases, University of Foggia, Riuniti Hospital, Foggia, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: d'Orsi
authors.affiliation: Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Marchioni
authors.affiliation: Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy; Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Tartara
authors.affiliation: Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Marchese
authors.affiliation: Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy; Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy.
authors.forename: Valter
authors.initials: V
authors.lastname: Rustioni
authors.affiliation: Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy; Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy.
authors.forename: Arrigo
authors.initials: A
authors.lastname: Moglia
authors.affiliation: Neurophysiopathology Unit, Epilepsy Centre, C. Mondino National Neurological Institute, Pavia, Italy. Electronic address: carloandrea.galimberti@mondino.it.
authors.forename: Carlo Andrea
authors.initials: CA
authors.lastname: Galimberti
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001921:Brain / Q000503:physiopathology*; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012640:Seizures / Q000503:physiopathology*; D012890:Sleep / Q000502:physiology; D055815:Young Adult
keywords: Ambulatory EEG; Elderly; Focal epilepsy; Interictal EEG; Sleep