Association of short-term cognitive decline and MCI-to-AD dementia conversion with CSF, MRI, amyloid- and 18F-FDG-PET imaging.

Abstract

Disease-modifying treatment trials are increasingly advanced to the prodromal or preclinical phase of Alzheimer's disease (AD), and inclusion criteria are based on biomarkers rather than clinical symptoms. Therefore, it is of great interest to determine which biomarkers should be combined to accurately predict conversion from mild cognitive impairment (MCI) to AD dementia. However, up to date, only few studies performed a complete A/T/N subject characterization using each of the CSF and imaging markers, or they only investigated long-term (≥ 2 years) prognosis. This study aimed to investigate the association between cerebrospinal fluid (CSF), magnetic resonance imaging (MRI), amyloid- and 18F-FDG positron emission tomography (PET) measures at baseline, in relation to cognitive changes and conversion to AD dementia over a short-term (12-month) period. We included 13 healthy controls, 49 MCI and 16 AD dementia patients with a clinical-based diagnosis and a complete A/T/N characterization at baseline. Global cortical amyloid-β (Aβ) burden was quantified using the 18F-AV45 standardized uptake value ratio (SUVR) with two different reference regions (cerebellar grey and subcortical white matter), whereas metabolism was assessed based on 18F-FDG SUVR. CSF measures included Aβ1-42, Aβ1-40, T-tau, P-tau181, and their ratios, and MRI markers included hippocampal volumes (HV), white matter hyperintensities, and cortical grey matter volumes. Cognitive functioning was measured by MMSE and RBANS index scores. All statistical analyses were corrected for age, sex, education, and APOE ε4 genotype. As a result, faster cognitive decline was most strongly associated with hypometabolism (posterior cingulate) and smaller hippocampal volume (e.g., Δstory recall: β = +0.43 [p < 0.001] and + 0.37 [p = 0.005], resp.) at baseline. In addition, faster cognitive decline was significantly associated with higher baseline Aβ burden only if SUVR was referenced to the subcortical white matter (e.g., Δstory recall: β = -0.28 [p = 0.020]). Patients with MCI converted to AD dementia at an annual rate of 31%, which could be best predicted by combining neuropsychological testing (visuospatial construction skills) with either MRI-based HV or 18F-FDG-PET. Combining all three markers resulted in 96% specificity and 92% sensitivity. Neither amyloid-PET nor CSF biomarkers could discriminate short-term converters from non-converters.

• Authors: Julie Ottoy, Ellis Niemantsverdriet, Jeroen Verhaeghe, Ellen De Roeck, Hanne Struyfs, Charisse Somers, Leonie Wyffels, Sarah Ceyssens, Sara Van Mossevelde, Tobi Van den Bossche, Christine Van Broeckhoven, Annemie Ribbens, Maria Bjerke, Sigrid Stroobants, Sebastiaan Engelborghs, Steven Staelens
• Journal: NeuroImage. Clinical (Neuroimage Clin) Vol. 22 Pg. 101771 ( 2019) ISSN: 2213-1582 [Electronic] Netherlands
• PMID: 30927601 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.

Chemical References

• Amyloid beta-Peptides
• Aniline Compounds
• Biomarkers
• Ethylene Glycols
• Fluorodeoxyglucose F18
• florbetapir

Topics

• Aged
• Alzheimer Disease (cerebrospinal fluid, metabolism, pathology, physiopathology)
• Amyloid beta-Peptides (metabolism)
• Aniline Compounds
• Biomarkers
• Cognitive Dysfunction (cerebrospinal fluid, metabolism, pathology, physiopathology)
• Disease Progression
• Ethylene Glycols
• Female
• Fluorodeoxyglucose F18
• Follow-Up Studies
• Hippocampus (diagnostic imaging, pathology)
• Humans
• Magnetic Resonance Imaging (standards)
• Male
• Middle Aged
• Positron-Emission Tomography (standards)
• Sensitivity and Specificity