Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2000 May;10(1):39-48.
doi: 10.1002/(sici)1097-0193(200005)10:1<39::aid-hbm50>3.0.co;2-b.

Voxel-based analysis of confounding effects of age and dementia severity on cerebral metabolism in Alzheimer's disease

E Salmon  1 , F Collette, C Degueldre, C Lemaire, G Franck
Affiliations

Voxel-based analysis of confounding effects of age and dementia severity on cerebral metabolism in Alzheimer's disease

E Salmon et al. Hum Brain Mapp. 2000 May.

Abstract

Alzheimer's disease is characterized by early hippocampal lesions, but neuropathological and functional imaging studies have also demonstrated involvement of associative cortices in patients suffering from this illness. New image-processing technologies have led to demonstration of predominant posteromedial cortical metabolic impairment in the disease. Confounding effects of both age and dementia severity on brain metabolism were assessed using categorical and correlational analyses performed with Statistical Parametric Mapping. Posterior cingulate and precuneus metabolism, assessed by positron emission tomography, was significantly correlated with age in a population of 46 patients with probable Alzheimer's disease. Metabolism in posterior cingulate and precuneus was higher in elderly than in younger patients with a diagnosis of Alzheimer's disease, even when dementia severity was taken as a confounding covariate. The data suggest that the sensitivity of positron emission tomography for the diagnosis of Alzheimer's disease is reduced in elderly cases, where less severe pathology is sufficient to induce clinical symptoms of dementia. Conversely, higher posteromedial metabolic impairment in early onset cases may reflect greater density of regional cerebral lesions or major decrease of functional afferences in a richly connected multimodal associative area. Posterior cingulate metabolism was also correlated to dementia severity, even when age was taken as a confounding covariate, whereas metabolism in the hippocampal formation was not shown to correlate with global cognitive deficit. Functional correlation was maintained between posterior cingulate and middle frontal cortex in demented patients as in elderly controls. The key role of posteromedial cortex in cognitive dysfunction assessed in Alzheimer's disease is probably related to its highly integrated position within attentional, visuospatial and memory neuronal networks.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Statistical parametric map (P < 0.001) showing significant decrease of metabolism in posterior cingulate cortex in patients with Alzheimer's disease compared to a control population.
Figure 2
Figure 2
Illustration of the significant correlation obtained between age and metabolism in posterior cingulate region in Alzheimer's disease but not in controls.
Figure 3
Figure 3
Statistical parametric map (P < 0.001) showing the correlation between dementia severity and metabolism in posterior cingulate and premotor cortices of Alzheimer patients.
Figure 4
Figure 4
Illustration of the significant correlation obtained between dementia severity (score on mini mental state examination) and metabolism in posterior cingulate region in Alzheimer's disease.
Figure 5
Figure 5
Statistical parametric map (P < 0.01) showing that middle frontal metabolism is significantly correlated with that in posterior cingulate.
See this image and copyright information in PMC

References

    1. Alavi A, Newberg AB, Souder E, Berlin JA (1993): Quantitative analysis of PET and MRI data in normal aging and Alzheimer's disease: atrophy weighted total brain metabolism and absolute whole brain metabolism as reliable discriminators. J Nucl Med 34: 1681–1687. - PubMed
    1. Alexander GE, Furey ML, Grady CL, Pietrini P, Brady DR, Mentis MJ, Schapiro MB (1997): Association of premorbid intellectual function with cerebral metabolism in Alzheimer's disease: Implication for the cognitive reserve hypothesis. Am J Psychiat 154: 165–172. - PubMed
    1. APA . (1994): Diagnostic and statistical manual of mental disorders (4th Ed.). Washington, D.C.: American Psychiatric Association.
    1. Baleydier C, Mauguiere F (1980): The duality of the cingulate gyrus in monkey. Neuroanatomical study and functional hypothesis. Brain 103: 525–554. - PubMed
    1. Baleydier C, Mauguiere F (1985): Anatomical evidence for medial pulvinar connections with the posterior cingulate cortex, the retrosplenial area, and the posterior parahippocampal gyrus in monkey. J Comp Neurol 232: 219–228. - PubMed

Publication types