Structural and microstructural thalamocortical network disruption in sporadic behavioural variant frontotemporal dementia.
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ABSTRACT: Background
Using multi-block methods we combined multimodal neuroimaging metrics of thalamic morphology, thalamic white matter tract diffusion metrics, and cortical thickness to examine changes in behavioural variant frontotemporal dementia. (bvFTD).Method
Twenty-three patients with sporadic bvFTD and 24 healthy controls underwent structural and diffusion MRI scans. Clinical severity was assessed using the Clinical Dementia Rating scale and behavioural severity using the Frontal Behaviour Inventory by patient caregivers. Thalamic volumes were manually segmented. Anterior and posterior thalamic radiation fractional anisotropy and mean diffusivity were extracted using Tract-Based Spatial Statistics. Finally, cortical thickness was assessed using Freesurfer. We used shape analyses, diffusion measures, and cortical thickness as features in sparse multi-block partial least squares (PLS) discriminatory analyses to classify participants within bvFTD or healthy control groups. Sparsity was tuned with five-fold cross-validation repeated 10 times. Final model fit was assessed using permutation testing. Additionally, sparse multi-block PLS was used to examine associations between imaging features and measures of dementia severity.Results
Bilateral anterior-dorsal thalamic atrophy, reduction in mean diffusivity of thalamic projections, and frontotemporal cortical thinning, were the main features predicting bvFTD group membership. The model had a sensitivity of 96%, specificity of 68%, and was statistically significant using permutation testing (p = 0.012). For measures of dementia severity, we found similar involvement of regional thalamic and cortical areas as in discrimination analyses, although more extensive thalamo-cortical white matter metric changes.Conclusions
Using multimodal neuroimaging, we demonstrate combined structural network dysfunction of anterior cortical regions, cortical-thalamic projections, and anterior thalamic regions in sporadic bvFTD.
SUBMITTER: Jakabek D
PROVIDER: S-EPMC10371821 | biostudies-literature | 2023 Jul
REPOSITORIES: biostudies-literature
Publications
Structural and microstructural thalamocortical network disruption in sporadic behavioural variant frontotemporal dementia.
Jakabek David D Power Brian D BD Spotorno Nicola N Macfarlane Matthew D MD Walterfang Mark M Velakoulis Dennis D Nilsson Christer C Waldö Maria Landqvist ML Lätt Jimmy J Nilsson Markus M van Westen Danielle D Lindberg Olof O Looi Jeffrey C L JCL Santillo Alexander F AF
NeuroImage. Clinical 20230711
<h4>Background</h4>Using multi-block methods we combined multimodal neuroimaging metrics of thalamic morphology, thalamic white matter tract diffusion metrics, and cortical thickness to examine changes in behavioural variant frontotemporal dementia. (bvFTD).<h4>Method</h4>Twenty-three patients with sporadic bvFTD and 24 healthy controls underwent structural and diffusion MRI scans. Clinical severity was assessed using the Clinical Dementia Rating scale and behavioural severity using the Frontal ...[more]
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Project description:IntroductionPsychotropic medication (PM) use in behavioral-variant frontotemporal dementia (bvFTD) is higher than in other dementias. However, no information exists on whether PM use differs between sporadic and genetic bvFTD.MethodsWe analyzed data from sporadic and genetic bvFTD participants with PM prescriptions in the Advancing Research and Treatment in Frontotemporal Lobar Degeneration/Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects study. We estimated ordinal odds ratio (OOR) of having more PM comparing sporadic and genetic bvFTD. Finally, we explored the neuropsychiatric symptom (NPS) combinations using classification and regression trees (CART).ResultsWe included 263 with sporadic and 193 with genetic bvFTD. The OOR for sporadic bvFTD to be on PM was 1.75 (95% confidence interval: 1.21 to 2.53) for the fully adjusted model. CART revealed the most common NPS combination was apathy + personality changes in 18% of participants.DiscussionParticipants with sporadic bvFTD were twice as likely to be on PM compared to genetic bvFTD. The reason for increased PM usage in sporadic bvFTD participants should be further investigated.HighlightsWe report on patients with behavioral variant frontotemporal dementia (bvFTD). We evaluated the psychotropic medication (PM) prescription at baseline in the cohort. Patients with sporadic bvFTD had more prescriptions for PM than genetic patients. The frequency of symptoms combination was different in sporadic and genetic bvFTD.
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