title: Interactive effects of vascular risk burden and advanced age on cerebral blood flow.
abstract: Vascular risk factors and cerebral blood flow (CBF) reduction have been linked to increased risk of cognitive impairment and Alzheimer's disease (AD); however the possible moderating effects of age and vascular risk burden on CBF in late life remain understudied. We examined the relationships among elevated vascular risk burden, age, CBF, and cognition. Seventy-one non-demented older adults completed an arterial spin labeling MR scan, neuropsychological assessment, and medical history interview. Relationships among vascular risk burden, age, and CBF were examined in a priori regions of interest (ROIs) previously implicated in aging and AD. Interaction effects indicated that, among older adults with elevated vascular risk burden (i.e., multiple vascular risk factors), advancing age was significantly associated with reduced cortical CBF whereas there was no such relationship for those with low vascular risk burden (i.e., no or one vascular risk factor). This pattern was observed in cortical ROIs including medial temporal (hippocampus, parahippocampal gyrus, uncus), inferior parietal (supramarginal gyrus, inferior parietal lobule, angular gyrus), and frontal (anterior cingulate, middle frontal gyrus, medial frontal gyrus) cortices. Furthermore, among those with elevated vascular risk, reduced CBF was associated with poorer cognitive performance. Such findings suggest that older adults with elevated vascular risk burden may be particularly vulnerable to cognitive change as a function of CBF reductions. Findings support the use of CBF as a potential biomarker in preclinical AD and suggest that vascular risk burden and regionally-specific CBF changes may contribute to differential age-related cognitive declines.
authors: Psychology Service, VA San Diego Healthcare System San Diego, CA, USA ; Department of Psychiatry, University of California, San Diego La Jolla, CA, USA.
authors: Katherine J
authors: KJ
authors: Bangen
authors: Department of Psychology, University of Southern California Los Angeles, CA, USA.
authors: Daniel A
authors: DA
authors: Nation
authors: San Diego Joint Doctoral Program in Clinical Psychology, San Diego State University/University of California San Diego, CA, USA.
authors: Lindsay R
authors: LR
authors: Clark
authors: San Diego Joint Doctoral Program in Clinical Psychology, San Diego State University/University of California San Diego, CA, USA.
authors: Alexandrea L
authors: AL
authors: Harmell
authors: Department of Psychiatry, University of California, San Diego La Jolla, CA, USA ; Research Service, VA San Diego Healthcare System San Diego, CA, USA.
authors: Christina E
authors: CE
authors: Wierenga
authors: San Diego Joint Doctoral Program in Clinical Psychology, San Diego State University/University of California San Diego, CA, USA.
authors: Sheena I
authors: SI
authors: Dev
authors: Department of Psychiatry, University of California, San Diego La Jolla, CA, USA ; Research Service, VA San Diego Healthcare System San Diego, CA, USA.
authors: Lisa
authors: L
authors: Delano-Wood
authors: Department of Psychiatry, University of California, San Diego La Jolla, CA, USA.
authors: Zvinka Z
authors: ZZ
authors: Zlatar
authors: Department of Neurosciences, University of California San Diego, La Jolla, CA, USA.
authors: David P
authors: DP
authors: Salmon
authors: Department of Radiology, University of California San Diego, La Jolla, CA, USA.
authors: Thomas T
authors: TT
authors: Liu
authors: Psychology Service, VA San Diego Healthcare System San Diego, CA, USA ; Department of Psychiatry, University of California, San Diego La Jolla, CA, USA.
authors: Mark W
authors: MW
authors: Bondi
keywords: aging; arterial spin labeling; cognition; vascular risk factors