title: Depressive symptoms and cognitive decline in community-dwelling older adults.
abstract: OBJECTIVE
  To examine the temporal association between depressive symptoms and cognitive functioning and estimate the effect measure modification of the apolipoprotein E (APOE) epsilon4 allele on this relationship.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  General community.
  
  
  METHODS
  Population-based sample of 598 cognitively intact older adults aged 60 and older, with re-assessments after 3 (N=479) and 6 years (N=412).
  
  
  METHODS
  Depressive symptoms (Symptom Checklist) and neurocognitive functioning (memory, Visual Verbal Learning Test; attention, Stroop Color-Word Test; processing speed, Letter Digit Substitution Test; general cognition, Mini-Mental State Examination). Longitudinal associations were assessed using linear mixed models. The risk for cognitive impairment, no dementia (CIND) was examined using logistic regression.
  
  
  RESULTS
  Adjusting for age, sex, education, and baseline cognition, the rate of change in memory z-scores was 0.00, -0.11, -0.20, and -0.37 for those in the lowest (reference group), second, third, and highest depressive symptom quartiles at baseline, respectively (P<.001 for highest vs lowest quartile). The odds ratios for developing CIND with amnestic features were 1.00, 0.87, 0.69, and 2.98 for the four severity groups (P=.05 for highest vs lowest quartile). Associations were strongest for those with persistent depressive symptoms, defined as high depressive symptoms at baseline and at least one follow-up visit. Results were similar for processing speed and global cognitive function but were not as strong for attention. No APOE interaction was observed.
  
  
  CONCLUSIONS
  Depression and APOE act independently to increase the risk for cognitive decline and may provide targets for prevention and early treatment.
authors.affiliation: Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, European Graduate School of Neuroscience, Maastricht University, Maastricht, the Netherlands. s.koehler@np.unimaas.nl
authors.forename: Sebastian
authors.initials: S
authors.lastname: Köhler
authors.forename: Martin P J
authors.initials: MP
authors.lastname: van Boxtel
authors.forename: Jim
authors.initials: J
authors.lastname: van Os
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Thomas
authors.forename: John T
authors.initials: JT
authors.lastname: O'Brien
authors.forename: Jelle
authors.initials: J
authors.lastname: Jolles
authors.forename: Frans R J
authors.initials: FR
authors.lastname: Verhey
authors.forename: Judith
authors.initials: J
authors.lastname: Allardyce
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001057:Apolipoproteins E / Q000235:genetics; D003071:Cognition; D015331:Cohort Studies; D003863:Depression / Q000523:psychology*; D005094:Exophthalmos; D005260:Female; D005838:Genotype; D006801:Humans; D057187:Independent Living; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D001057:Apolipoproteins E