title: Cognitive functioning and the natural course of depressive symptoms in late life.
abstract: OBJECTIVE
  To investigate whether specific domains of cognitive functioning predict the natural course of depressive symptoms in older people.
  
  
  METHODS
  Using the nationally representative, population-based cohort of the Longitudinal Aging Study Amsterdam, 281 participants with clinically relevant depressive symptoms (Center for Epidemiological Studies Depression Scale ≥16) aged 55 years and older were followed longitudinally during a period of 6 years.
  
  
  METHODS
  Using a maximum of 14 successive Center for Epidemiological Studies Depression Scale observations, three clinical course types of depressive symptoms were defined. At baseline, general cognitive functioning was assessed using the Mini-Mental State Exam, memory performance (immediate recall and retention) by means of the auditory verbal learning test, and processing speed by means of a timed coding task.
  
  
  RESULTS
  Remission, fluctuating course, and chronic course were seen in 22%, 50%, and 28%, respectively. In univariate analyses, a slowed processing speed was associated with a chronic course of depressive symptoms, as compared with remission (mean: 21.5, SD: 6.6, versus mean: 24.6, SD: 6.8, t = 2.78, df = 139, p < 0.001). Using multivariate regression techniques, this association remained significant after correcting for potential confounders and a number of risk factors for vascular brain damage (odds ratio: 1.08, 95% confidence interval: 1.01-1.14). Neither global cognitive functioning nor memory performance was associated with any course type of depressive symptoms.
  
  
  CONCLUSIONS
  We found an independent association of a slowed processing speed with a poor natural course of depressive symptoms in older people. In clinical practice, when dealing with an older depressed person with comorbid cognitive decline, processing speed might be a more useful tool than the Mini-Mental State Exam in predicting the prognosis.
authors.affiliation: Department of Geriatric Medicine, Altrecht, Institute for Mental Health Care Den Dolder, The Netherlands. j.sanders@vumc.nl
authors.forename: Joost B
authors.initials: JB
authors.lastname: Sanders
authors.forename: Marijke A
authors.initials: MA
authors.lastname: Bremmer
authors.forename: Hannie C
authors.initials: HC
authors.lastname: Comijs
authors.forename: Dorly J H
authors.initials: DJ
authors.lastname: Deeg
authors.forename: Indrag K
authors.initials: IK
authors.lastname: Lampe
authors.forename: Aartjan T F
authors.initials: AT
authors.lastname: Beekman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000150:complications; D002561:Cerebrovascular Disorders / Q000150:complications; D002908:Chronic Disease; D003071:Cognition / Q000502:physiology*; D003863:Depression / Q000209:etiology / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D009483:Neuropsychological Tests; D012307:Risk Factors