Associations among education, age, and the dementia with Lewy bodies (DLB) metabolic pattern: A European‐DLB consortium project

Abstract

Introduction We assessed the influence of education as a proxy of cognitive reserve and age on the dementia with Lewy bodies (DLB) metabolic pattern. Methods Brain 18F‐fluorodeoxyglucose positron emission tomography and clinical/demographic information were available in 169 probable DLB patients included in the European DLB‐consortium database. Principal component analysis identified brain regions relevant to local data variance. A linear regression model was applied to generate age‐ and education‐sensitive maps corrected for Mini‐Mental State Examination score, sex (and either education or age). Results Age negatively covaried with metabolism in bilateral middle and superior frontal cortex, anterior and posterior cingulate, reducing the expression of the DLB‐typical cingulate island sign (CIS). Education negatively covaried with metabolism in the left inferior parietal cortex and precuneus (making the CIS more prominent). Discussion These findings point out the importance of tailoring interpretation of DLB biomarkers considering the concomitant effect of individual, non–disease‐related variables such as age and cognitive reserve.

Added value of semiquantitative analysis of brain FDG-PET for the differentiation between MCI-Lewy bodies and MCI due to Alzheimer’s disease

“…Therefore, the weight of PO impairment was higher than the relative preservation of the PCC. This could have been influenced by aging and low cognitive reserve, as stated above [11,13]. Indeed, 24 (61.5%) of the MCI-LB patients have less than 8 years of education, 29 (74.3%) are older than 75, and 13 (33.3%) have both the features.…”

“…These cases gave us insight into some peculiarities that might have misled the readers, such as (i) the early prodromal stage and consequently the very mildly impaired brain metabolism, (ii) a severe parieto-occipital involvement with a milder impairment of PCC metabolism thus mimicking the DLB pattern in some MCI-AD patients, and (iii) a higher involvement of PCC without a clear CIS or a typical DLB pattern in some other MCI-LB patients. The latter was likely driven by higher age, lower education [13], and lower cognitive scores [11,39] which are known factors influencing the expression of the CIS.…”

“…Another FDG-PET main feature of DLB is the relative preservation of posterior cingulate metabolism ("cingulate island sign," CIS) that seems at least as accurate as occipital hypometabolism in overt dementia, with sensitivity of 77% and specificity of 80% between DLB and AD [7]. The CIS might be especially specific, albeit less sensitive, in early DLB [11,12] but it is significantly influenced by age and educational level [13]. Such limitations and an overall accuracy below the 80% are the main reasons why FDG-PET is only considered a supportive biomarker in the current DLB criteria [10].…”

PET Imaging in Dementia: Mini-Review and Canadian Perspective for Clinical Use

“…the ability of the brain to cope with neurodegeneration by using alternative functional pathways. 32 Synaptic vesicle protein 2a (SV2A) PET As a still experimental PET neurodegeneration marker, a number of tracers targeting the synaptic vesicle protein 2a receptor (SV2A) have been developed. [33][34][35][36] These have shown to represent synaptic density.…”