title: Arterial stiffness is associated with age-related differences in cerebrovascular conductance.
abstract: To determine if arterial stiffness is associated with age-related differences in cerebrovascular conductance and reactivity, twenty-eight apparently healthy sedentary young (25±1 years; n=15) and older (67±1 years; n=13) adults were studied. Brachial-ankle pulse wave velocity (baPWV) was measured as an index of arterial stiffness. Cerebrovascular reactivity was determined by measuring changes in mean blood velocity in the middle cerebral artery under normocapnic, hypocapnic and hypercapnic conditions. Mean baPWV was greater (p<0.05) in older compared with young adults. At baseline, mean cerebral blood flow velocity and cerebrovascular conductance index were lower (p<0.05) in older compared with young adults under normocapnic, hypocapnic and hypercapnic conditions. There were no significant group differences in cerebrovascular reactivity when they were adjusted for stimuli (i.e., end-tidal CO2 concentrations) in most perturbation conditions except for the normocapnia to hypercapnia condition. baPWV was negatively associated with cerebrovascular conductance index at all conditions (all p<0.05). We concluded that arterial stiffness was associated with age-related differences in cerebrovascular conductance and that there were no apparent age-associated differences in cerebrovascular reactivity.
authors.affiliation: Faculty of Sports Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Tussana
authors.initials: T
authors.lastname: Jaruchart
authors.affiliation: Faculty of Medicine, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Nijasri C
authors.initials: NC
authors.lastname: Suwanwela
authors.affiliation: Department of Kinesiology and Health Education, University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Tanaka
authors.affiliation: Faculty of Sports Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand. Electronic address: daroonwanc@hotmail.com.
authors.forename: Daroonwan
authors.initials: D
authors.lastname: Suksom
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D055109:Ankle Brachial Index; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000502:physiology; D063177:Pulse Wave Analysis; D017585:Ultrasonography, Doppler, Transcranial; D059289:Vascular Stiffness / Q000502:physiology*; D014666:Vasomotor System / Q000502:physiology; D055815:Young Adult
keywords: Aging; Cerebral vasomotor reactivity; Pulse wave velocity; Transcranial Doppler