title: Carotid artery plaque progression and cognitive decline: the Tromsø Study 1994-2008.
abstract: BACKGROUND
  Carotid atherosclerosis is a risk factor for stroke and cognitive decline, but knowledge on how progression of carotid atherosclerosis affects cognitive function in stroke-free individuals is scarce.
  
  
  METHODS
  In the population-based Tromsø study, we calculated the change in ultrasound-assessed carotid plaque number and total plaque area from baseline (survey 4) to follow-up 7 years later (survey 5) in 4274 middle-aged stroke-free subjects. Cognitive function was assessed at follow-up by the verbal memory test, the digit-symbol coding test, and the tapping test and repeated after an additional 6 years in a subgroup of 2042 subjects (survey 6). Associations between the average of survey 4 and survey 5 plaque scores and the progression of plaque scores and cognitive test scores were assessed in regression analyses adjusted for baseline age, sex, education, depression, and cardiovascular risk factors.
  
  
  RESULTS
  Progression of total plaque area was associated with lower scores in the digit-symbol coding test (multivariable adjusted standardized β, -0.03; 95% CI, -0.05 to -0.00; P = 0.04) and the tapping test (β, -0.03; 95% CI, -0.06 to -0.00; P = 0.03). Similar results were seen for progression of plaque number. The average plaque scores were associated with lower scores in all cognitive tests (P-values ≤ 0.01). No association was found between plaque scores and cognitive decline.
  
  
  CONCLUSIONS
  The average plaque scores were associated with lower scores in all cognitive tests. Progression of plaque scores was associated with lower scores in the digit-symbol coding test and the tapping test, but not with the verbal memory test or with cognitive decline.
authors.affiliation: Department of Community Medicine, University of Tromsø, Tromsø, Norway. kjell.a.arntzen@uit.no
authors.forename: K A
authors.initials: KA
authors.lastname: Arntzen
authors.forename: H
authors.initials: H
authors.lastname: Schirmer
authors.forename: S H
authors.initials: SH
authors.lastname: Johnsen
authors.forename: T
authors.initials: T
authors.lastname: Wilsgaard
authors.forename: E B
authors.initials: EB
authors.lastname: Mathiesen
mesh_terms: D016893:Carotid Stenosis / Q000150:complications / Q000000981:diagnostic imaging*; D003071:Cognition; D003072:Cognition Disorders / Q000453:epidemiology* / Q000209:etiology; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D014463:Ultrasonography