title: Elevated cerebrovascular resistance index is associated with cognitive dysfunction in the very-old.
abstract: Age-related vascular changes, including blood pressure elevation and cerebral blood flow (CBF) reduction, are associated with cognitive decline and Alzheimer's disease (AD). Evidence suggests that the relationship between blood pressure and dementia risk varies between younger and older samples within the elderly population.
  
  
  
  We examined the relationship between mean arterial pressure (MAP), CBF, and cognition in young-old (60 to 75 years of age) versus very-old (80+ years of age) adults. Fifty-eight non-demented older adults completed an arterial spin labeling MRI scan, and an index of cerebrovascular resistance (CVRi) was estimated for each participant by calculating the ratio of MAP and CBF.
  
  
  
  Results demonstrated a similar negative relationship between MAP and CBF across both age groups. However, very-old participants exhibited elevated CVRi and reduced CBF compared to young-old participants in regions implicated in AD and cerebral small vessel disease. Furthermore, significant age by CVRi interactions revealed that elevated CVRi in the thalamus was inversely related to verbal fluency performance in the very-old group.
  
  
  
  Findings support CVRi as a potential vascular biomarker and suggest that regionally-specific vascular changes may contribute to cognitive decline, particularly in the very-old.
authors.affiliation: San Diego State University/University of California, San Diego Joint Doctoral Program in Clinical Psychology, San Diego, CA, USA. lrclark@medicine.wisc.edu.|Wisconsin Alzheimer's Institute, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA. lrclark@medicine.wisc.edu.
authors.forename: Lindsay R
authors.initials: LR
authors.lastname: Clark
authors.affiliation: Department of Psychology, University of Southern California, Los Angeles, CA, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Nation
authors.affiliation: Department of Psychiatry, University of California San Diego, San Diego, CA, USA.|Department of Veterans Affairs, San Diego Healthcare System, San Diego, CA, USA.
authors.forename: Christina E
authors.initials: CE
authors.lastname: Wierenga
authors.affiliation: Department of Psychiatry, University of California San Diego, San Diego, CA, USA.
authors.forename: Katherine J
authors.initials: KJ
authors.lastname: Bangen
authors.affiliation: San Diego State University/University of California, San Diego Joint Doctoral Program in Clinical Psychology, San Diego, CA, USA.
authors.forename: Sheena I
authors.initials: SI
authors.lastname: Dev
authors.affiliation: Center for Functional MRI, University of California San Diego, San Diego, CA, USA.
authors.forename: David D
authors.initials: DD
authors.lastname: Shin
authors.affiliation: Department of Psychiatry, University of California San Diego, San Diego, CA, USA.|Department of Veterans Affairs, San Diego Healthcare System, San Diego, CA, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Delano-Wood
authors.affiliation: Center for Functional MRI, University of California San Diego, San Diego, CA, USA.
authors.forename: Thomas T
authors.initials: TT
authors.lastname: Liu
authors.affiliation: Department of Neurosciences, University of California San Diego, San Diego, CA, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Rissman
authors.affiliation: Department of Psychiatry, University of California San Diego, San Diego, CA, USA. mbondi@ucsd.edu.|Department of Veterans Affairs, San Diego Healthcare System, San Diego, CA, USA. mbondi@ucsd.edu.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Bondi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D062186:Arterial Pressure / Q000502:physiology*; D001921:Brain / Q000098:blood supply* / Q000000981:diagnostic imaging; D002560:Cerebrovascular Circulation / Q000502:physiology*; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013113:Spin Labels; D014655:Vascular Resistance / Q000502:physiology*
chemical_list: D013113:Spin Labels