title: Sleep disturbance relates to neuropsychological functioning in late-life depression.
abstract: BACKGROUND
  Sleep-wake disturbance in older people is a risk factor for depression onset and recurrence. The aim of this study was to determine if objective sleep-wake disturbance in late-life depression relates to neuropsychological functioning.
  
  
  METHODS
  Forty-four older patients with a lifetime history of major depression and 22 control participants underwent psychiatric, medical and neuropsychological assessments. Participants completed self-report sleep measures, sleep diaries and wore wrist actigraphy for two weeks. Outcome measures included sleep latency, the number and duration of nocturnal awakenings and the overall sleep efficiency.
  
  
  RESULTS
  Patients with depression had a greater duration of nocturnal awakenings and poorer sleep efficiency, in comparison to control participants. Sleep disturbance in patients was associated with greater depression severity and later ages of depression onset. It also related to poorer psychomotor speed, poorer verbal and visual learning, poorer semantic fluency as well as poorer performance on tests of executive functioning. These relationships largely remained significant after controlling for depression and estimated apnoea severity.
  
  
  CONCLUSIONS
  This sample had only mild levels of depression severity and results require replication in patients with moderate to severe depression. The inclusion of polysomnography and circadian markers would be useful to delineate the specific features of sleep-wake disturbance that are critical to cognitive performance.
  
  
  CONCLUSIONS
  Sleep-wake disturbance in older patients with depression is related to neuropsychological functioning and to later ages of illness onset. This study suggests that common neurobiological changes may underpin these disease features, which may, in turn, warrant early identification and management.
authors: Clinical Research Unit, Brain & Mind Research Institute, Australia. sharon.naismith@sydney.edu.au
authors: Sharon L
authors: SL
authors: Naismith
authors: Naomi L
authors: NL
authors: Rogers
authors: Simon J G
authors: SJ
authors: Lewis
authors: Zoë
authors: Z
authors: Terpening
authors: Tony
authors: T
authors: Ip
authors: Keri
authors: K
authors: Diamond
authors: Louisa
authors: L
authors: Norrie
authors: Ian B
authors: IB
authors: Hickie
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003072:Cognition Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008609:Mental Status Schedule / Q000706:statistics & numerical data; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D010555:Personality Inventory / Q000706:statistics & numerical data; D011594:Psychometrics; D007319:Sleep Initiation and Maintenance Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*