학술논문

Network Connectivity Alterations across the MAPT Mutation Clinical Spectrum
Document Type
article
Source
Annals of Neurology. 94(4)
Subject
Biomedical and Clinical Sciences
Neurosciences
Clinical Sciences
Dementia
Brain Disorders
Alzheimer's Disease Related Dementias (ADRD)
Clinical Research
Frontotemporal Dementia (FTD)
Mental Health
Alzheimer's Disease
Rare Diseases
Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD)
Aging
Acquired Cognitive Impairment
Neurodegenerative
Biomedical Imaging
2.1 Biological and endogenous factors
Aetiology
Neurological
Humans
Cross-Sectional Studies
tau Proteins
Brain
Mutation
Gray Matter
Magnetic Resonance Imaging
Frontotemporal Dementia
Biomarkers
ARTFL/LEFFTDS/ALLFTD Consortia
Neurology & Neurosurgery
Clinical sciences
Language
Abstract
ObjectiveMicrotubule-associated protein tau (MAPT) mutations cause frontotemporal lobar degeneration, and novel biomarkers are urgently needed for early disease detection. We used task-free functional magnetic resonance imaging (fMRI) mapping, a promising biomarker, to analyze network connectivity in symptomatic and presymptomatic MAPT mutation carriers.MethodsWe compared cross-sectional fMRI data between 17 symptomatic and 39 presymptomatic carriers and 81 controls with (1) seed-based analyses to examine connectivity within networks associated with the 4 most common MAPT-associated clinical syndromes (ie, salience, corticobasal syndrome, progressive supranuclear palsy syndrome, and default mode networks) and (2) whole-brain connectivity analyses. We applied K-means clustering to explore connectivity heterogeneity in presymptomatic carriers at baseline. Neuropsychological measures, plasma neurofilament light chain, and gray matter volume were compared at baseline and longitudinally between the presymptomatic subgroups defined by their baseline whole-brain connectivity profiles.ResultsSymptomatic and presymptomatic carriers had connectivity disruptions within MAPT-syndromic networks. Compared to controls, presymptomatic carriers showed regions of connectivity alterations with age. Two presymptomatic subgroups were identified by clustering analysis, exhibiting predominantly either whole-brain hypoconnectivity or hyperconnectivity at baseline. At baseline, these two presymptomatic subgroups did not differ in neuropsychological measures, although the hypoconnectivity subgroup had greater plasma neurofilament light chain levels than controls. Longitudinally, both subgroups showed visual memory decline (vs controls), yet the subgroup with baseline hypoconnectivity also had worsening verbal memory and neuropsychiatric symptoms, and extensive bilateral mesial temporal gray matter decline.InterpretationNetwork connectivity alterations arise as early as the presymptomatic phase. Future studies will determine whether presymptomatic carriers' baseline connectivity profiles predict symptomatic conversion. ANN NEUROL 2023;94:632-646.