Differences in Sex Distribution Between Genetic and Sporadic Frontotemporal Dementia

Background: Reported sex distributions differ between frontotemporal dementia (FTD) cohorts. Possible explanations are the evolving clinical criteria of FTD and its subtypes and the discovery of FTD causal genetic mutations that has resulted in varying demographics. Objective: Our aim was to determine the sex distribution of sporadic and genetic FTD cases and its subtypes in an international cohort. Methods: We included 910 patients with behavioral variant frontotemporal dementia (bvFTD; n = 654), non-fluent variant primary progressive aphasia (nfvPPA; n = 99), semantic variant primary progressive aphasia (svPPA; n = 117), and right temporal variant frontotemporal dementia (rtvFTD; n = 40). We compared sex distribution between genetic and sporadic FTD using χ2-tests. Results: The genetic FTD group consisted of 51.2% males, which did not differ from sporadic FTD (57.8% male, p = 0.08). In the sporadic bvFTD subgroup, males were predominant in contrast to genetic bvFTD (61.6% versus 52.9% males, p = 0.04). In the other clinical FTD subgroups, genetic cases were underrepresented and within the sporadic cases sex distribution was somewhat equal. Conclusion: The higher male prevalence in sporadic bvFTD may provide important clues for its differential pathogenesis and warrants further research.

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Laughter as a Paradigm of Socio-emotional Signal Processing in Dementia

10.21203/rs.3.rs-118292/v1 ◽

2020 ◽

Author(s):

Harri Sivasathiaseelan ◽

Charles R Marshall ◽

Elia Benhamou ◽

Janneke EP van Leeuwen ◽

Rebecca L Bond ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Signal Processing ◽

Frontotemporal Dementia ◽

Primary Progressive Aphasia ◽

Identification Accuracy ◽

Progressive Aphasia ◽

Primary Progressive ◽

Emotional Dysfunction ◽

Semantic Variant

Abstract Background: Laughter is a fundamental communicative signal in our relations with other people and is used to convey a diverse repertoire of social and emotional information. It is therefore potentially a useful probe of impaired socio-emotional signal processing in neurodegenerative diseases. Here we investigated the cognitive and affective processing of laughter systematically in patients representing all major syndromes of frontotemporal dementia, a disease spectrum characterised by severe socio-emotional dysfunction, as well as typical amnestic Alzheimer’s disease in relation to healthy age-matched individuals. Methods: We assessed cognitive labelling and valence rating of samples of spontaneous (mirthful and hostile) and volitional (posed) laughter versus two auditory control conditions (a synthetic laughter-like stimulus and spoken numbers) in 47 patients with frontotemporal dementia (22 with behavioural variant frontotemporal dementia, 12 with semantic variant primary progressive aphasia and 13 with nonfluent-agrammatic primary progressive aphasia), 15 patients with typical amnestic Alzheimer’s disease and 20 healthy age-matched individuals. Neuroanatomical associations of laughter processing were assessed using voxel-based morphometry of patients’ brain MR images. Results: While all dementia syndromes were associated with impaired identification of laughter subtypes relative to healthy controls, this was significantly more severe overall in frontotemporal dementia than in Alzheimer’s disease and particularly in the behavioural and semantic variants, which also showed abnormal affective evaluation of laughter. Certain striking syndromic signatures emerged, including enhanced liking for hostile laughter in behavioural variant frontotemporal dementia, impaired processing of synthetic laughter in the nonfluent-agrammatic variant (consistent with a generic complex auditory perceptual deficit) and ‘numerophilia’ in the semantic variant. Across the patient cohort, overall laughter identification accuracy correlated with regional grey matter in a core network encompassing inferior frontal and cingulo-insular cortices; and more specific correlates of laughter identification accuracy were delineated in cortical regions mediating affective disambiguation (identification of hostile and posed laughter in orbitofrontal cortex) and authenticity (social intent) decoding (identification of mirthful and posed laughter in anteromedial prefrontal cortex).Conclusions: These findings reveal a rich diversity of cognitive and affective laughter phenotypes in canonical dementia syndromes and suggest that laughter is an informative probe of neural mechanisms underpinning socio-emotional dysfunction in neurodegenerative disease.

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Neuroinflammation and protein aggregation co-localize across the frontotemporal dementia spectrum

Brain ◽

10.1093/brain/awaa033 ◽

2020 ◽

Vol 143 (3) ◽

pp. 1010-1026 ◽

Cited By ~ 12

Author(s):

W Richard Bevan-Jones ◽

Thomas E Cope ◽

P Simon Jones ◽

Sanne S Kaalund ◽

Luca Passamonti ◽

...

Keyword(s):

Protein Aggregation ◽

Frontotemporal Dementia ◽

Primary Progressive Aphasia ◽

Amyloid Β Protein ◽

Progressive Aphasia ◽

Primary Progressive ◽

Activated Microglia ◽

Clinical Syndromes ◽

Semantic Variant

Abstract The clinical syndromes of frontotemporal dementia are clinically and neuropathologically heterogeneous, but processes such as neuroinflammation may be common across the disease spectrum. We investigated how neuroinflammation relates to the localization of tau and TDP-43 pathology, and to the heterogeneity of clinical disease. We used PET in vivo with (i) 11C-PK-11195, a marker of activated microglia and a proxy index of neuroinflammation; and (ii) 18F-AV-1451, a radioligand with increased binding to pathologically affected regions in tauopathies and TDP-43-related disease, and which is used as a surrogate marker of non-amyloid-β protein aggregation. We assessed 31 patients with frontotemporal dementia (10 with behavioural variant, 11 with the semantic variant and 10 with the non-fluent variant), 28 of whom underwent both 18F-AV-1451 and 11C-PK-11195 PET, and matched control subjects (14 for 18F-AV-1451 and 15 for 11C-PK-11195). We used a univariate region of interest analysis, a paired correlation analysis of the regional relationship between binding distributions of the two ligands, a principal component analysis of the spatial distributions of binding, and a multivariate analysis of the distribution of binding that explicitly controls for individual differences in ligand affinity for TDP-43 and different tau isoforms. We found significant group-wise differences in 11C-PK-11195 binding between each patient group and controls in frontotemporal regions, in both a regions-of-interest analysis and in the comparison of principal spatial components of binding. 18F-AV-1451 binding was increased in semantic variant primary progressive aphasia compared to controls in the temporal regions, and both semantic variant primary progressive aphasia and behavioural variant frontotemporal dementia differed from controls in the expression of principal spatial components of binding, across temporal and frontotemporal cortex, respectively. There was a strong positive correlation between 11C-PK-11195 and 18F-AV-1451 uptake in all disease groups, across widespread cortical regions. We confirmed this association with post-mortem quantification in 12 brains, demonstrating strong associations between the regional densities of microglia and neuropathology in FTLD-TDP (A), FTLD-TDP (C), and FTLD-Pick's. This was driven by amoeboid (activated) microglia, with no change in the density of ramified (sessile) microglia. The multivariate distribution of 11C-PK-11195 binding related better to clinical heterogeneity than did 18F-AV-1451: distinct spatial modes of neuroinflammation were associated with different frontotemporal dementia syndromes and supported accurate classification of participants. These in vivo findings indicate a close association between neuroinflammation and protein aggregation in frontotemporal dementia. The inflammatory component may be important in shaping the clinical and neuropathological patterns of the diverse clinical syndromes of frontotemporal dementia.

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Early-Onset Frontotemporal Dementia-Related Semantic Variant of Primary Progressive Aphasia

Clinical Nuclear Medicine ◽

10.1097/rlu.0000000000003934 ◽

2021 ◽

Vol Publish Ahead of Print ◽

Author(s):

Spyridon Tsiouris ◽

Charalampos Bougias ◽

Spyridon Konitsiotis ◽

Athanasios Papadopoulos ◽

Andreas Fotopoulos

Keyword(s):

Frontotemporal Dementia ◽

Early Onset ◽

Primary Progressive Aphasia ◽

Progressive Aphasia ◽

Primary Progressive ◽

Semantic Variant

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Supplemental Material for The Concept of Regularization: Resolving the Problem of Surface Dyslexia in Semantic Variant Primary Progressive Aphasia Across Different Languages

Neuropsychology ◽

10.1037/neu0000611.supp ◽

2019 ◽

Keyword(s):

Primary Progressive Aphasia ◽

Progressive Aphasia ◽

Primary Progressive ◽

Semantic Variant ◽

Surface Dyslexia

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Primary Progressive Aphasia: Toward a Pathophysiological Synthesis

Current Neurology and Neuroscience Reports ◽

10.1007/s11910-021-01097-z ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

Justina Ruksenaite ◽

Anna Volkmer ◽

Jessica Jiang ◽

Jeremy CS Johnson ◽

Charles R Marshall ◽

...

Keyword(s):

Care Management ◽

Primary Progressive Aphasia ◽

Disease Stage ◽

Major Step ◽

Progressive Aphasia ◽

Primary Progressive ◽

New Findings ◽

Critical Issues ◽

Semantic Variant ◽

Auditory Impairments

Abstract Purpose of Review The term primary progressive aphasia (PPA) refers to a diverse group of dementias that present with prominent and early problems with speech and language. They present considerable challenges to clinicians and researchers. Recent Findings Here, we review critical issues around diagnosis of the three major PPA variants (semantic variant PPA, nonfluent/agrammatic variant PPA, logopenic variant PPA), as well as considering ‘fragmentary’ syndromes. We next consider issues around assessing disease stage, before discussing physiological phenotyping of proteinopathies across the PPA spectrum. We also review evidence for core central auditory impairments in PPA, outline critical challenges associated with treatment, discuss pathophysiological features of each major PPA variant, and conclude with thoughts on key challenges that remain to be addressed. Summary New findings elucidating the pathophysiology of PPA represent a major step forward in our understanding of these diseases, with implications for diagnosis, care, management, and therapies.

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Breakdowns in Informativeness of Naturalistic Speech Production in Primary Progressive Aphasia

Brain Sciences ◽

10.3390/brainsci11020130 ◽

2021 ◽

Vol 11 (2) ◽

pp. 130

Author(s):

Jeanne Gallée ◽

Claire Cordella ◽

Evelina Fedorenko ◽

Daisy Hochberg ◽

Alexandra Touroutoglou ◽

...

Keyword(s):

Primary Progressive Aphasia ◽

Speech Analysis ◽

Clinical Settings ◽

Functional Communication ◽

Or Efficiency ◽

Progressive Aphasia ◽

Primary Progressive ◽

Communication Impairment ◽

Semantic Variant ◽

Lower Production

“Functional communication” refers to an individual’s ability to communicate effectively in his or her everyday environment, and thus is a paramount skill to monitor and target therapeutically in people with aphasia. However, traditional controlled-paradigm assessments commonly used in both research and clinical settings often fail to adequately capture this ability. In the current study, facets of functional communication were measured from picture-elicited speech samples from 70 individuals with mild primary progressive aphasia (PPA), including the three variants, and 31 age-matched controls. Building upon methods recently used by Berube et al. (2019), we measured the informativeness of speech by quantifying the content of each patient’s description that was relevant to a picture relative to the total amount of speech they produced. Importantly, form-based errors, such as mispronunciations of words, unusual word choices, or grammatical mistakes are not penalized in this approach. We found that the relative informativeness, or efficiency, of speech was preserved in non-fluent variant PPA patients as compared with controls, whereas the logopenic and semantic variant PPA patients produced significantly less informative output. Furthermore, reduced informativeness in the semantic variant is attributable to a lower production of content units and a propensity for self-referential tangents, whereas for the logopenic variant, a lower production of content units and relatively ”empty” speech and false starts contribute to this reduction. These findings demonstrate that functional communication impairment does not uniformly affect all the PPA variants and highlight the utility of naturalistic speech analysis for measuring the breakdown of functional communication in PPA.

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Exploring dementia and neuronal ceroid lipofuscinosis genes in 100 FTD-like patients from 6 towns and rural villages on the Adriatic Sea cost of Apulia

Scientific Reports ◽

10.1038/s41598-021-85494-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Celeste Sassi ◽

Rosa Capozzo ◽

Monia Hammer ◽

Chiara Zecca ◽

Monica Federoff ◽

...

Keyword(s):

Late Onset ◽

Neuronal Ceroid Lipofuscinosis ◽

Primary Progressive Aphasia ◽

Complex Spectrum ◽

Site Mutation ◽

Progressive Aphasia ◽

Pathogenic Mechanisms ◽

Primary Progressive ◽

Ceroid Lipofuscinosis ◽

Sporadic Cases

AbstractFrontotemporal dementia (FTD) refers to a complex spectrum of clinically and genetically heterogeneous disorders. Although fully penetrant mutations in several genes have been identified and can explain the pathogenic mechanisms underlying a great portion of the Mendelian forms of the disease, still a significant number of families and sporadic cases remains genetically unsolved. We performed whole exome sequencing in 100 patients with a late-onset and heterogeneous FTD-like clinical phenotype from Apulia and screened mendelian dementia and neuronal ceroid lipofuscinosis genes. We identified a nonsense mutation in SORL1 VPS domain (p.R744X), in 2 siblings displaying AD with severe language problems and primary progressive aphasia and a near splice-site mutation in CLCN6 (p.S116P) segregating with an heterogeneous phenotype, ranging from behavioural FTD to FTD with memory onset and to the logopenic variant of primary progressive aphasia in one family. Moreover 2 sporadic cases with behavioural FTD carried heterozygous mutations in the CSF1R Tyrosin kinase flanking regions (p.E573K and p.R549H). By contrast, only a minority of patients carried pathogenic C9orf72 repeat expansions (1%) and likely moderately pathogenic variants in GRN (p.C105Y, p.C389fs and p.C139R) (3%). In concert with recent studies, our findings support a common pathogenic mechanisms between FTD and neuronal ceroid lipofuscinosis and suggests that neuronal ceroid lipofuscinosis genes should be investigated also in dementia patients with predominant frontal symptoms and language impairments.

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