title: Sleeping in? The impact of age and depressive sub-type on hypersomnia.
abstract: BACKGROUND
  While early morning wakening is held to be a classic feature of melancholia, we investigate the clinical observation that young patients with melancholia and bipolar depression tend to be more likely to report hypersomnia.
  
  
  METHODS
  We examine age-related rates of those two sleep disturbance patterns in a consecutive set of out-patients with differing depressive sub-types assessed over a 20-year period.
  
  
  RESULTS
  Hypersomnia was more likely to be reported than early morning wakening across all age bands by those with non-melancholic depression. Hypersomnia was also more likely than early morning wakening in younger patients with melancholia and bipolar disorder but, with age, early morning wakening became the dominant pattern.
  
  
  CONCLUSIONS
  The study was retrospective, undertaken in a sample attending a tertiary referral unit and artefactual determinants of the associations were not pursued.
  
  
  CONCLUSIONS
  We speculate that hypersomnia may be a non-specific homeostatic coping response to stress and thus to the non-melancholic depressive disorders, but that this pattern is overruled by an early morning wakening pattern in the more biological depressive sub-types as the individual ages, perhaps reflecting a noradrenergic contribution.
authors.affiliation: School of Psychiatry, University of New South Wales, Black Dog Institute, Sydney, NSW, Australia. g.parker@unsw.edu.au
authors.forename: G
authors.initials: G
authors.lastname: Parker
authors.forename: G
authors.initials: G
authors.lastname: Malhi
authors.forename: D
authors.initials: D
authors.lastname: Hadzi-Pavlovic
authors.forename: K
authors.initials: K
authors.lastname: Parker
mesh_terms: D000328:Adult; D000367:Age Factors; D001714:Bipolar Disorder / Q000453:epidemiology*; D003863:Depression / Q000453:epidemiology*; D006970:Disorders of Excessive Somnolence / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood
chemical_list: D009638:Norepinephrine