title: Association of pulsatile and mean cerebral blood flow velocity with age and neuropsychological performance.
abstract: Low cerebral blood flow velocity is associated with cognitive decline. However, the association between pulsatile brain blood flow velocity and cognition has not been investigated. High pulsatile hemodynamic stress in the brain may impair cognitive function through damage to small cerebral vessels. The current objective was to examine the cross-sectional association of pulsatile and mean cerebral blood flow velocity with age and neuropsychological performance. We also examined whether cerebral blood flow velocity was associated with aortic pulse pressure, a measure of arterial ageing and aortic stiffness. Cerebral blood flow velocity was measured in the middle cerebral artery using Transcranial Doppler Ultrasonography (TDU) while neuropsychological performance was measured using a computerized cognitive test battery. Aortic pulse pressure was non-invasively derived from applanation tonometry of the radial artery. The sample comprised 160 healthy adults aged 50-70 years. Results indicated that increasing age correlated with lower mean (r=-0.23, p<0.01) and higher pulsatile (r=0.27, p<0.01) brain blood flow velocity. In multivariate adjusted models, both peripheral (β=0.28, p<0.05) and aortic (β=0.24, p<0.05) pulse pressure were associated with higher pulsatile flow velocity through the middle cerebral artery. In adjusted models, neither mean nor pulsatile cerebral blood flow velocity was associated with performance on any cognitive task. In conclusion, arterial ageing was associated with increased pulsatile hemodynamic stress in the brain. However, this was not associated with impaired neuropsychological performance.
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn 3122, Australia. Electronic address: matthewpase@gmail.com.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Pase
authors.affiliation: Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton 3168, Australia.
authors.forename: Natalie A
authors.initials: NA
authors.lastname: Grima
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn 3122, Australia.
authors.forename: Con
authors.initials: C
authors.lastname: Stough
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn 3122, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Scholey
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn 3122, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Pipingas
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D001011:Aorta / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D015999:Multivariate Analysis; D009483:Neuropsychological Tests; D011673:Pulsatile Flow / Q000502:physiology*; D017534:Radial Artery / Q000502:physiology; D013647:Task Performance and Analysis; D017585:Ultrasonography, Doppler, Transcranial
keywords: Blood pressure; Brain; Cerebral blood flow; Cerebrovascular; Cognition; Neuropsychology