title: Sleep problems in bipolar disorders: more than just insomnia.
abstract: OBJECTIVE
  Sleep problems in bipolar disorder (BD) are common, but reported rates vary from 10% to 80%, depending on definitions, methodologies and management of potential confounding factors. This multicenter study seeks to address these issues and also compares BD cases with Hypersomnia as well as the more commonly investigated Insomnia and No Sleep Problem groups.
  
  
  METHODS
  A cross-sectional comparison of sleep profiles in 563 BD I and II individuals who participated in a structured assessment of demographic, clinical, illness history and treatment variables.
  
  
  RESULTS
  Over 40% cases met criteria for Insomnia and 29% for Hypersomnia. In univariate analysis, Insomnia was associated with BD II depression whilst Hypersomnia was associated with BD I depression or euthymia. After controlling for confounders and covariates, it was demonstrated that Hypersomnia cases were significantly more likely to be younger, have BD I and be prescribed antidepressants whilst Insomnia cases had longer illness durations and were more likely to be prescribed benzodiazepines and hypnotics.
  
  
  CONCLUSIONS
  Whilst Insomnia symptoms are common in BD, Hypersomnia is a significant, frequently underexplored problem. Detailed analyses of large representative clinical samples are critical to extending our knowledge of differences between subgroups defined by sleep profile.
authors.affiliation: Faculty of Medicine, Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.|Department of Psychiatry, St. Olavs University Hospital, Trondheim, Norway.
authors.forename: M K
authors.initials: MK
authors.lastname: Steinan
authors.affiliation: Academic Psychiatry, Institute of Neuroscience, Newcastle University, Newcastle, UK.|Centre for Affective Disorders, Institute of Psychiatry, London, UK.
authors.forename: J
authors.initials: J
authors.lastname: Scott
authors.affiliation: NORMENT, KG Jebsen Centre for Psychosis Research, Oslo University Hospital, Oslo, Norway.
authors.forename: T V
authors.initials: TV
authors.lastname: Lagerberg
authors.affiliation: NORMENT, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.|NORMENT, Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway.
authors.forename: I
authors.initials: I
authors.lastname: Melle
authors.affiliation: NORMENT, KG Jebsen Centre for Psychosis Research, Oslo University Hospital, Oslo, Norway.|NORMENT, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: O A
authors.initials: OA
authors.lastname: Andreassen
authors.affiliation: Faculty of Medicine, Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.|Department of Psychiatry, St. Olavs University Hospital, Trondheim, Norway.
authors.forename: A E
authors.initials: AE
authors.lastname: Vaaler
authors.affiliation: Faculty of Medicine, Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.|Department of Psychiatry, St. Olavs University Hospital, Trondheim, Norway.
authors.forename: G
authors.initials: G
authors.lastname: Morken
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000453:epidemiology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D006970:Disorders of Excessive Somnolence / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D007319:Sleep Initiation and Maintenance Disorders / Q000453:epidemiology*
keywords: bipolar I disorder; bipolar II disorder; hypersomnia; insomnia; sleep