Cerebral glucose metabolism in preclinical and prodromal Alzheimer’s disease

Abstract

Assessment of regional cerebral glucose metabolism by (18)F-2-fluoro-2-deoxy-D-glucose (FDG)-PET at resting state is a standard functional technique to assess cerebral function. Group studies identified significant regional metabolic impairment in asymptomatic individuals at increased risk for dementia. Substantial impairment of FDG uptake in temporoparietal association cortices emerges as a reliable predictor of rapid progression to dementia in mild cognitive impairment patients and could, therefore, serve as a biomarker for the diagnosis of prodromal Alzheimer's disease. Frontal and temporoparietal metabolic impairment is closely related to progression of disease in longitudinal studies, and multicenter studies suggest its utility as an outcome parameter to increase the efficiency of therapeutic trials.

Changes in Brain Glioma Incidence and Laterality Correlates with Use of Mobile Phones - a Nationwide Population Based Study in Israel

“…Authors concluded, "This finding is of unknown clinical significance". Notably the finding in that study, an increase in intracellular metabolism of glucose should be viewed in light of the fact that a decrease in the brain glucose metabolism is associated with the development of Alzheimer disease (Daulatzai, 2010;Herholz, 2010). Other studies have shown other, non-carcinogens effects on the brain such as local increase in oxygen consumption (Curcio et al, 2009) and an effect on regional cerebral blood flow (Alto et al, 2006) Interpretation of those results and their clinical relevance and implication is not clear; as is the debate weather they represent a deleterious effect or a protective effect.…”

Mild Thyroid Deficiency in the Elderly

“…Thyroid hormones are crucial for brain development and function: thyroid failure at any age causes cognition to deteriorate because thyroid hormones are essential for adequately sustaining the energy (glucose)-consuming processes needed for neurotransmission, memory, and other higher brain functions (Herholz, 2010;Patel et al, 2011). Low brain uptake of glucose is commonly associated with deteriorating cognition and Alzheimer's disease and can be present decades before clinical evidence of Alzheimer's disease occurs (Herholz, 2010).…”

“…Low brain uptake of glucose is commonly associated with deteriorating cognition and Alzheimer's disease and can be present decades before clinical evidence of Alzheimer's disease occurs (Herholz, 2010). Brain hypometabolism therefore appears to be a precursor lesion increasing the risk of at least some forms of cognitive decline.…”

The link between cardiovascular risk, Alzheimer's disease, and mild cognitive impairment: support from recent functional neuroimaging studies

“…14 FDG-PET studies have identified regional deficits of glucose metabolism in the hippocampus as well as in the posterior cingulate gyrus of patients with MCI. 15 Functional neuroimaging studies --using fMRI, FDG-PET, and SPECT --have been used to predict conversion from MCI to AD. [16][17][18] Because MCI is etiologically heterogeneous, 19 FDG-PET has been investigated as a tool to estimate which MCI patients have high likelihood of converting to AD.…”