Psychomotor Slowing in Mild Cognitive Impairment, Alzheimer’s Disease and Lewy Body Dementia: Mechanisms and Diagnostic Value

Background Dopaminergic imaging is an established biomarker for dementia with Lewy bodies, but its diagnostic accuracy at the mild cognitive impairment (MCI) stage remains uncertain. Aims To provide robust prospective evidence of the diagnostic accuracy of dopaminergic imaging at the MCI stage to either support or refute its inclusion as a biomarker for the diagnosis of MCI with Lewy bodies. Method We conducted a prospective diagnostic accuracy study of baseline dopaminergic imaging with [123I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane single-photon emission computerised tomography (123I-FP-CIT SPECT) in 144 patients with MCI. Images were rated as normal or abnormal by a panel of experts with access to striatal binding ratio results. Follow-up consensus diagnosis based on the presence of core features of Lewy body disease was used as the reference standard. Results At latest assessment (mean 2 years) 61 patients had probable MCI with Lewy bodies, 26 possible MCI with Lewy bodies and 57 MCI due to Alzheimer's disease. The sensitivity of baseline FP-CIT visual rating for probable MCI with Lewy bodies was 66% (95% CI 52–77%), specificity 88% (76–95%) and accuracy 76% (68–84%), with positive likelihood ratio 5.3. Conclusions It is over five times as likely for an abnormal scan to be found in probable MCI with Lewy bodies than MCI due to Alzheimer's disease. Dopaminergic imaging appears to be useful at the MCI stage in cases where Lewy body disease is suspected clinically.

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The differential diagnostic value of the callosal angle and Evans index in mild cognitive impairment and Alzheimer's disease

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405616666201223150004 ◽

2020 ◽

Vol 16 ◽

Author(s):

Mengqi Liu ◽

Jing Zhang ◽

Linxiong Zong ◽

Wenping Fan ◽

Botao Wang ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Diagnostic Value ◽

Imaging Biomarker ◽

Imaging Biomarkers ◽

P Value ◽

Significant Difference ◽

Evans Index

Background: Callosal angle (CA) and Evans index (EI) had been considered as imaging biomarkers to diagnosis normal-pressure hydrocephalus as traditional MR measurement methods. Objective: The current study was aimed to evaluate the differential diagnostic value of CA and EI in the mild cognitive impairment (MCI) and Alzheimer’s disease (AD). Methods: Five-hundred and two subjects were selected from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database, which included 168 normal controls (NC), 233 MCI and 101 AD patients. The structural MR images were interactively applied with multiplanar reconstruction to measure the CA and EI. Results: CA presented no significant difference among NC, MCI and AD groups (H value = 3.848, P value = 0.146), and EI was demonstrated the higher in MCI and AD groups than that in NC groups (P = 0.000 and 0.001, respectively). MCI group had significant larger EI (0.29±0.04) than that (0.27±0.03) in NC group in 70-75 years old sub-groups. ROC showed that the area under the curve was 0.704±0.045 for NC-MCI in 70-75 years old groups. The correlation analysis indicated that EI was significantly negatively related with MMSE scores of MCI patients (r = -0.131, P = 0.046). Conclusion: EI might serve as a screening imaging biomarker for MCI in 70-75 years old, and show limited differential value for the diagnosis of AD. CA could present no diagnostic value for MCI and AD in the current study.

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The Diagnostic Value of Exosome-Derived Biomarkers in Alzheimer's Disease and Mild Cognitive Impairment: A Meta-Analysis

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2021.637218 ◽

2021 ◽

Vol 13 ◽

Author(s):

Wenmin Xing ◽

Wenyan Gao ◽

Xiaoling Lv ◽

Xiaogang Xu ◽

Zhongshan Zhang ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Likelihood Ratio ◽

Meta Analysis ◽

Diagnostic Value ◽

Biomedical Literature ◽

Cochrane Library ◽

Diagnostic Likelihood Ratio

Background: Alzheimer's disease (AD) diagnoses once depended on neuropathologic examination. Now, many widely used, validated biomarkers benefits for monitoring of AD neuropathologic changes. Exosome-derived biomarker studies have reported them to be significantly related to AD's early occurrence and development, although the findings are inconclusive. The aim of this meta-analysis was to identify exosome-derived biomarkers for the diagnosis of AD and mild cognitive impairment (MCI).Methods: PubMed, PubMed Central, Web of Science, Embase, Google Scholar, Cochrane Library, the Chinese National Knowledge Infrastructure (CNKI), and the Chinese Biomedical Literature Database (CBM) were searched for studies assessing the diagnostic value of biomarkers, including data describing the pooled sensitivity (SEN), specificity (SPE), positive diagnostic likelihood ratio (DLR+), negative diagnostic likelihood ratio (DLR–), diagnostic odds ratio (DOR), and area under the curve (AUC). The quality of the included studies was assessed using RevMan 5.3 software. Publication bias was analyzed.Results: In total, 19 eligible studies, including 3,742 patients, were selected for this meta-analysis. The SEN, SPE, DLR+, DLR–, DOR, and AUC (95% confidence intervals) of exosome-derived biomarkers in the diagnosis of AD or MCI were 0.83 (0.76–0.87), 0.82 (0.77–0.86), 4.53 (3.46–5.93), 0.21 (0.15–0.29), 17.27 (11.41–26.14), and 0.89 (0.86–0.92), respectively. Sub-group analyses revealed that studies based on serum or microRNA (miRNA) analysis, and those of Caucasian populations, AD patients, patient sample size >50, neuron-derived exosomes (NDE) from plasma and p-tau had higher sensitivity, specificity, and AUC values.Conclusion: Exosome-derived biomarkers have shown potential diagnostic value in AD and MCI, although further research is required for confirmation.

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