title: Depressive symptoms are associated with daytime sleepiness and subjective sleep quality in dementia with Lewy bodies.
abstract: Sleep problems and depression are common symptoms in dementia with Lewy bodies (DLB), where patients typically experience subjectively poor sleep quality, fatigue and excessive daytime sleepiness. However, whilst sleep disturbances have been linked to depression, this relationship has not received much attention in DLB. The present cross-sectional study addresses this by examining whether depressive symptoms are specifically associated with subjective sleep quality and daytime sleepiness in DLB, and by examining other contributory factors.
  
  
  
  DLB patients (n = 32) completed the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS) and the 15-item Geriatric Depression Scale (GDS-15). Motor and cognitive functioning was also assessed. Pearson correlations were used to assess the relationship between GDS-15, ESS and PSQI scores.
  
  
  
  GDS-15 scores were positively associated with both ESS (r = 0.51, p < 0.01) and PSQI (r = 0.59, p < 0.001) scores.
  
  
  
  Subjective poor sleep and daytime sleepiness were associated with depressive symptoms in DLB. Given the cross-sectional nature of the present study, the directionality of this relationship cannot be determined, although this association did not appear to be mediated by sleep quality or daytime sleepiness. Nevertheless, these findings have clinical relevance; daytime sleepiness or poor sleep quality might indicate depression in DLB, and subsequent work should examine whether the treatment of depression can reduce excessive daytime sleepiness and improve sleep quality in DLB patients. Alternatively, more rigorous screening for sleep problems in DLB might assist the treatment of depression. © 2015 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons, Ltd.
authors.affiliation: Institute of Neuroscience, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: Greg J
authors.initials: GJ
authors.lastname: Elder
authors.affiliation: Institute of Neuroscience, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: Sean J
authors.initials: SJ
authors.lastname: Colloby
authors.affiliation: Institute of Neuroscience, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: Debra J
authors.initials: DJ
authors.lastname: Lett
authors.affiliation: Department of Psychiatry, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK.
authors.forename: John T
authors.initials: JT
authors.lastname: O'Brien
authors.affiliation: Institute of Neuroscience, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: Kirstie N
authors.initials: KN
authors.lastname: Anderson
authors.affiliation: Institute of Neuroscience, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Burn
authors.affiliation: Institute of Neuroscience, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: Ian G
authors.initials: IG
authors.lastname: McKeith
authors.affiliation: Institute of Neuroscience, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: John-Paul
authors.initials: JP
authors.lastname: Taylor
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000209:etiology* / Q000523:psychology; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D020961:Lewy Body Disease / Q000150:complications / Q000523:psychology; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D007319:Sleep Initiation and Maintenance Disorders / Q000523:psychology*
keywords: daytime sleepiness; dementia with Lewy bodies; depression; depressive symptoms; sleep quality