Categorical and correlational analyses of baseline fluorodeoxyglucose positron emission tomography images from the Alzheimer's Disease Neuroimaging Initiative (ADNI)

Banner Alzheimer's Institute and Banner Good Samaritan PET Center, Phoenix, AZ, USA.
NeuroImage (Impact Factor: 6.36). 06/2009; 45(4):1107-16. DOI: 10.1016/j.neuroimage.2008.12.072
Source: PubMed


In mostly small single-center studies, Alzheimer's disease (AD) is associated with characteristic and progressive reductions in fluorodeoxyglucose positron emission tomography (PET) measurements of the regional cerebral metabolic rate for glucose (CMRgl). The AD Neuroimaging Initiative (ADNI) is acquiring FDG PET, volumetric magnetic resonance imaging, and other biomarker measurements in a large longitudinal multi-center study of initially mildly affected probable AD (pAD) patients, amnestic mild cognitive impairment (aMCI) patients, who are at increased AD risk, and cognitively normal controls (NC), and we are responsible for analyzing the PET images using statistical parametric mapping (SPM). Here we compare baseline CMRgl measurements from 74 pAD patients and 142 aMCI patients to those from 82 NC, we correlate CMRgl with categorical and continuous measures of clinical disease severity, and we compare apolipoprotein E (APOE) varepsilon4 carriers to non-carriers in each of these subject groups. In comparison with NC, the pAD and aMCI groups each had significantly lower CMRgl bilaterally in posterior cingulate, precuneus, parietotemporal and frontal cortex. Similar reductions were observed when categories of disease severity or lower Mini-Mental State Exam (MMSE) scores were correlated with lower CMRgl. However, when analyses were restricted to the pAD patients, lower MMSE scores were significantly correlated with lower left frontal and temporal CMRgl. These findings from a large, multi-site study support previous single-site findings, supports the characteristic pattern of baseline CMRgl reductions in AD and aMCI patients, as well as preferential anterior CMRgl reductions after the onset of AD dementia.

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    • "One such extensively used neuroimaging technique is 18 F- Fluorodeoxyglucose positron emission tomography (FDG-PET) imaging, which can be used to evaluate the cerebral metabolic rate of glucose (CMRgl). Numerous FDG- PET studies (Nestor et al. 2003; Mosconi et al. 2005, 2008; Langbaum et al. 2009) have demonstrated significant reductions of CMRgl in brain regions in patients with AD and its prodromal stage mild cognitive impairment (MCI), compared with normal control (NC) subjects. These reduction could be used for the early detection of AD. "
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