title: Genetic effects on sleep/wake variation of seizures.
abstract: OBJECTIVE
  There is a complex bidirectional relationship between sleep and epilepsy. Sleep/wake timing of seizures has been investigated for several individual seizure types and syndromes, but few large-scale studies of the timing of seizures exist in people with varied epilepsy types. In addition, the genetic contributions to seizure timing have not been well studied.
  
  
  METHODS
  Sleep/wake timing of seizures was determined for 1,395 subjects in 546 families enrolled in the Epilepsy Phenome/Genome Project (EPGP). We examined seizure timing among subjects with different epilepsy types, seizure types, epilepsy syndromes, and localization. We also examined the familial aggregation of sleep/wake occurrence of seizures.
  
  
  RESULTS
  Seizures in nonacquired focal epilepsy (NAFE) were more likely to occur during sleep than seizures in generalized epilepsy (GE), for both convulsive (odds ratio [OR] 5.2, 95% confidence interval [CI] 3.59-7.52) and nonconvulsive seizures (OR 4.2, 95% CI 2.48-7.21). Seizures occurring within 1 h of awakening were more likely to occur in patients with GE than with NAFE for both convulsive (OR 2.3, 95% CI 1.54-3.39) and nonconvulsive (OR 1.7, 95% CI 1.04-2.66) seizures. Frontal onset seizures were more likely than temporal onset seizures to occur during sleep. Sleep/wake timing of seizures in first-degree relatives predicted timing of seizures in the proband.
  
  
  CONCLUSIONS
  We found that sleep/wake timing of seizures is associated with both epilepsy syndrome and seizure type. In addition, we provide the first evidence for a genetic contribution to sleep/wake timing of seizures in a large group of individuals with common epilepsy syndromes.
authors.affiliation: Department of Neurology, Columbia University, New York, New York, U.S.A.|G.H. Sergievsky Center, Columbia University, New York, New York, U.S.A.
authors.forename: Melodie R
authors.initials: MR
authors.lastname: Winawer
authors.affiliation: Department of Neurology, Mayo Clinic, Jacksonville, Florida, U.S.A.
authors.forename: Jerry
authors.initials: J
authors.lastname: Shih
authors.affiliation: Department of Neurology, Columbia University, New York, New York, U.S.A.
authors.forename: Erin S
authors.initials: ES
authors.lastname: Beck
authors.affiliation: Kaiser Permanente Center for Health Research Northwest, Portland, Oregon, U.S.A.|Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, U.S.A.
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Hunter
authors.affiliation: Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, U.S.A.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Epstein
mesh_terms: D000328:Adult; D002940:Circadian Rhythm / Q000502:physiology; D004569:Electroencephalography / Q000379:methods; D005260:Female; D016678:Genome; D006801:Humans; D008297:Male; D012640:Seizures / Q000175:diagnosis* / Q000235:genetics* / Q000503:physiopathology; D012890:Sleep / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology*; D055815:Young Adult
keywords: Circadian; Epilepsy; Genetics; Seizure; Sleep