Cerebral perfusion and oxygenation differences in Alzheimer's disease risk

Fleisher, Adam S.; Podraza, Katherine M.; Bangen, Katherine J.; Taylor, Curtis; Sherzai, Ayesha; Sidhar, Kunal; Liu, Thomas T.; Dale, Anders M.; Buxton, Richard B.

doi:10.1016/j.neurobiolaging.2008.01.012

« Previous Next »Neurobiology of Aging
Volume 30, Issue 11 , Pages 1737-1748, November 2009

Cerebral perfusion and oxygenation differences in Alzheimer's disease risk

Adam S. Fleisher
- University of California at San Diego, Department of Neuroscience, United States
- Corresponding author at: University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92037-0949, United Sates. Tel.: +1 858 622 5868; fax: +1 858 452 3058.
Katherine M. Podraza
- University of California at San Diego, Department of Neuroscience, United States
Katherine J. Bangen
- University of California at San Diego, Department of Neuroscience, United States
Curtis Taylor
- University of California at San Diego, Department of Neuroscience, United States
Ayesha Sherzai
- University of California at San Diego, Department of Neuroscience, United States
Kunal Sidhar
- University of California at San Diego, New York Medical College, United States
Thomas T. Liu
- University of California at San Diego, Department of Radiology, United States
Anders M. Dale
- University of California at San Diego, Department of Neuroscience, United States
- University of California at San Diego, Department of Radiology, United States
Richard B. Buxton
- University of California at San Diego, Department of Radiology, United States

Received 19 October 2007; received in revised form 8 December 2007; accepted 18 January 2008. published online 06 March 2008.

Abstract

Functional MRI has demonstrated differences in response to memory performance based on risk for Alzheimer's disease (AD). The current study compared blood oxygen level dependent (BOLD) functional MRI response with arterial spin labeling (ASL) perfusion response during an associative encoding task and resting perfusion signal in different risk groups for AD. Thirteen individuals with a positive family history of AD and at least one copy of the apolipoprotien E ɛ4 (APOE4) gene (high risk) were compared to ten individuals without these risk factors (low risk). In the medial temporal lobes (MTLs) the high risk group had an elevated level of resting perfusion, and demonstrated decreased fractional BOLD and perfusion responses to the encoding task. However, there was no difference in the absolute cerebral blood flow during the task. These data demonstrate that individuals with increased risk for Alzheimer's disease have elevated MTL resting cerebral blood flow, which significantly influences apparent differences in BOLD activations. BOLD activations should be interpreted with caution, and do not necessarily reflect differences in neuronal activation.

Keywords: Alzheimer, APOE, Aging, MRI, fMRI, Imaging, Perfusion, BOLD, Risk factors, Family history, Arterial spin labeling, Cerebral blood flow (CBF)