title: Mild cognitive impairment is associated with selected functional markers: integrating concurrent, longitudinal, and stability effects.
abstract: OBJECTIVE
  We examined functional performance on multiple indicators for two cognitive status groups: (a) not impaired controls (NIC) and (b) mild cognitive impairment (MCI). We identified functional markers associated with differences, changes, and stability in cognitive status.
  
  
  METHODS
  In the Victoria Longitudinal Study (VLS) we examined cognitive status group effects in (a) cross-sectional functional performance, (b) longitudinal stability, (c) longitudinal functional performance change, and (d) functional marker prediction of later cognitive status. We assembled markers from five continuous clusters of MCI-related functional factors: biological vitality, activity lifestyle, psychosocial affect, subjective health, and global cognition. We used a cross-sectional sample and a two-wave longitudinal sample, stratified by age (mid-old, old-old) and cognitive status (MCI, NIC).
  
  
  RESULTS
  First, cross-sectional results showed that eight markers differentiated MCI and NIC adults, with the latter performing uniformly better. The groups differed on diastolic blood pressure, body mass index, positive and negative affect, MMSE, and the lifestyle indicators of self-maintenance, travel, and novel cognitive activities. Second, Wave 1 to Wave 2 stabilities in cognitive status classification were high. Third, several markers differentiated the stable (NIC-to-NIC, MCI-to-MCI) from the unstable (NIC-to-MCI, MCI-to-NIC) cognitive status groups. Fourth, five relevant markers for identifying older adults at risk for cognitive status changes were: diastolic blood pressure, self-maintenance activities, novel cognitive activities, positive affect, and global cognitive status.
  
  
  CONCLUSIONS
  Selected risk and protective factors differentiate persons classified with MCI from those not currently cognitively impaired, both cross-sectionally and longitudinally.
authors.affiliation: Department of Psychology.
authors.forename: Sanda
authors.initials: S
authors.lastname: Dolcos
authors.affiliation: Department of Psychology, University of Victoria.
authors.forename: Stuart W S
authors.initials: SWS
authors.lastname: MacDonald
authors.affiliation: Department of Psychology, University of Victoria.
authors.forename: Anna
authors.initials: A
authors.lastname: Braslavsky
authors.affiliation: Division of Neurology.
authors.forename: Richard
authors.identifier: 0000-0003-2977-8660
authors.initials: R
authors.lastname: Camicioli
authors.affiliation: Department of Psychology.
authors.forename: Roger A
authors.initials: RA
authors.lastname: Dixon
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D003071:Cognition; D060825:Cognitive Dysfunction / Q000523:psychology*; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008297:Male; D008568:Memory; D009483:Neuropsychological Tests