title: Association of visit-to-visit variability in blood pressure with cognitive function in old age: prospective cohort study.
abstract: OBJECTIVE
  To investigate the association between visit-to-visit variability in blood pressure and cognitive function in old age (>70 years).
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  PROSPER (PROspective Study of Pravastatin in the Elderly at Risk) study, a collaboration between centres in Ireland, Scotland, and the Netherlands.
  
  
  METHODS
  5461 participants, mean age 75.3 years, who were at risk of cardiovascular disease. Blood pressure was measured every three months during an average of 3.2 years. Visit-to-visit variability in blood pressure was defined as the standard deviation of blood pressure measurements between visits.
  
  
  METHODS
  Four domains of cognitive function, testing selective attention, processing speed, and immediate and delayed memory. In a magnetic resonance imaging substudy of 553 participants, structural brain volumes, cerebral microbleeds, infarcts, and white matter hyperintensities were measured.
  
  
  RESULTS
  Participants with higher visit-to-visit variability in systolic blood pressure had worse performance on all cognitive tests: attention (mean difference high versus low thirds) 3.08 seconds (95% confidence interval 0.85 to 5.31), processing speed -1.16 digits coded (95% confidence interval -1.69 to -0.63), immediate memory -0.27 pictures remembered (95% confidence interval -0.41 to -0.13), and delayed memory -0.30 pictures remembered (95% confidence interval -0.49 to -0.11). Furthermore, higher variability in both systolic and diastolic blood pressure was associated with lower hippocampal volume and cortical infarcts, and higher variability in diastolic blood pressure was associated with cerebral microbleeds (all P<0.05). All associations were adjusted for average blood pressure and cardiovascular risk factors.
  
  
  CONCLUSIONS
  Higher visit-to-visit variability in blood pressure independent of average blood pressure was associated with impaired cognitive function in old age.
authors.affiliation: Department of Gerontology and Geriatrics, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, Netherlands.
authors.forename: Behnam
authors.initials: B
authors.lastname: Sabayan
authors.forename: Liselotte W
authors.initials: LW
authors.lastname: Wijsman
authors.forename: Jessica C
authors.initials: JC
authors.lastname: Foster-Dingley
authors.forename: David J
authors.initials: DJ
authors.lastname: Stott
authors.forename: Ian
authors.initials: I
authors.lastname: Ford
authors.forename: Brendan M
authors.initials: BM
authors.lastname: Buckley
authors.forename: Naveed
authors.initials: N
authors.lastname: Sattar
authors.forename: J Wouter
authors.initials: JW
authors.lastname: Jukema
authors.forename: Matthias J P
authors.initials: MJ
authors.lastname: van Osch
authors.forename: Jeroen
authors.initials: J
authors.lastname: van der Grond
authors.forename: Mark A
authors.initials: MA
authors.lastname: van Buchem
authors.forename: Rudi G J
authors.initials: RG
authors.lastname: Westendorp
authors.forename: Anton J M
authors.initials: AJ
authors.lastname: de Craen
authors.forename: Simon P
authors.initials: SP
authors.lastname: Mooijaart
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000706:statistics & numerical data; D020520:Brain Infarction / Q000473:pathology / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000503:physiopathology; D003071:Cognition / Q000502:physiology*; D060825:Cognitive Dysfunction / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011446:Prospective Studies; D012044:Regression Analysis