1
|
Brown A, Salo SK, Savage G. Frontal variant Alzheimer's disease: A systematic narrative synthesis. Cortex 2023; 166:121-153. [PMID: 37356113 DOI: 10.1016/j.cortex.2023.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 01/03/2023] [Accepted: 05/22/2023] [Indexed: 06/27/2023]
Abstract
BACKGROUND Frontal variant Alzheimer's disease (fvAD) is considered a rare form of Alzheimer's disease (AD) which may be misdiagnosed as behavioural variant frontotemporal dementia (bvFTD). The literature has tended to conflate behavioural and executive dysfunction in fvAD cohorts and uses both AD diagnostic criteria and bvFTD diagnostic criteria to classify fvAD cohorts. The primary aim of this narrative synthesis was to summarise neuropsychological findings in fvAD cohorts in the context of established AD pathology. METHODS EMBASE, PsycINFO, PROQUEST and MEDLINE databases were searched for studies eligible for inclusion. Studies with both neuropsychological and biomarker evidence were included in the final narrative synthesis. RESULTS Ten studies were reviewed, including samples totalling 342 fvAD participants, 178 typical AD participants and 250 bvFTD participants. The review revealed areas worthy of further investigation that may aid differential diagnosis, including the degree of executive dysfunction in fvAD cohorts relative to bvFTD cohorts, the onset of behavioural and cognitive symptomatology, and similarities between fvAD and typical AD cognitive profiles. CONCLUSION There was insufficient neuropsychological evidence to clearly differentiate fvAD and bvFTD cognitive phenotypes, however, the review has highlighted distinctive features of the two disorders that may guide differential diagnosis in future research. Moreover, the review has highlighted issues involving disparate diagnostic criteria used to classify fvAD cohorts, contributing to variation in findings.
Collapse
Affiliation(s)
- Andrea Brown
- School of Psychological Sciences, Macquarie University, Sydney, Australia
| | - Sarah K Salo
- Department of Psychology, Swansea University, Swansea, UK; School of Psychology, University of Plymouth, Plymouth, UK
| | - Greg Savage
- School of Psychological Sciences, Macquarie University, Sydney, Australia.
| |
Collapse
|
2
|
Vinceti G, Gallingani C, Zucchi E, Martinelli I, Gianferrari G, Simonini C, Bedin R, Chiari A, Zamboni G, Mandrioli J. Young Onset Alzheimer's Disease Associated with C9ORF72 Hexanucleotide Expansion: Further Evidence for a Still Unsolved Association. Genes (Basel) 2023; 14:genes14040930. [PMID: 37107688 PMCID: PMC10138077 DOI: 10.3390/genes14040930] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/14/2023] [Accepted: 04/15/2023] [Indexed: 04/29/2023] Open
Abstract
Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are recognized as part of a disease continuum (FTD-ALS spectrum), in which the most common genetic cause is chromosome 9 open reading frame 72 (C9ORF72) gene hexanucleotide repeat expansion. The clinical phenotype of patients carrying this expansion varies widely and includes diseases beyond the FTD-ALS spectrum. Although a few cases of patients with C9ORF72 expansion and a clinical or biomarker-supported diagnosis of Alzheimer's disease (AD) have been described, they have been considered too sparse to establish a definite association between the C9ORF72 expansion and AD pathology. Here, we describe a C9ORF72 family with pleomorphic phenotypical expressions: a 54-year-old woman showing cognitive impairment and behavioral disturbances with both neuroimaging and cerebrospinal fluid (CSF) biomarkers consistent with AD pathology, her 49-year-old brother with typical FTD-ALS, and their 63-year-old mother with the behavioral variant of FTD and CSF biomarkers suggestive of AD pathology. The young onset of disease in all three family members and their different phenotypes and biomarker profiles make the simple co-occurrence of different diseases an extremely unlikely explanation. Our report adds to previous findings and may contribute to further expanding the spectrum of diseases associated with C9ORF72 expansion.
Collapse
Affiliation(s)
- Giulia Vinceti
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
| | - Chiara Gallingani
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Elisabetta Zucchi
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Ilaria Martinelli
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Giulia Gianferrari
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Cecilia Simonini
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Roberta Bedin
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
| | - Annalisa Chiari
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
| | - Giovanna Zamboni
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Jessica Mandrioli
- Neurology Unit, Azienda Ospedaliero Universitaria di Modena, 41126 Modena, Italy
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| |
Collapse
|
3
|
Wang R, Gao H, Xie H, Jia Z, Chen Q. Molecular imaging biomarkers in familial frontotemporal lobar degeneration: Progress and prospects. Front Neurol 2022; 13:933217. [PMID: 36051222 PMCID: PMC9424494 DOI: 10.3389/fneur.2022.933217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 07/25/2022] [Indexed: 12/01/2022] Open
Abstract
Familial frontotemporal lobar degeneration (FTLD) is a pathologically heterogeneous group of neurodegenerative diseases with diverse genotypes and clinical phenotypes. Three major mutations were reported in patients with familial FTLD, namely, progranulin (GRN), microtubule-associated protein tau (MAPT), and the chromosome 9 open reading frame 72 (C9orf72) repeat expansion, which could cause neurodegenerative pathological changes years before symptom onset. Noninvasive quantitative molecular imaging with PET or single-photon emission CT (SPECT) allows for selective visualization of the molecular targets in vivo to investigate brain metabolism, perfusion, neuroinflammation, and pathophysiological changes. There was increasing evidence that several molecular imaging biomarkers tend to serve as biomarkers to reveal the early brain abnormalities in familial FTLD. Tau-PET with 18F-flortaucipir and 11C-PBB3 demonstrated the elevated tau position in patients with FTLD and also showed the ability to differentiate patterns among the different subtypes of the mutations in familial FTLD. Furthermore, dopamine transporter imaging with the 11C-DOPA and 11C-CFT in PET and the 123I-FP-CIT in SPECT revealed the loss of dopaminergic neurons in the asymptomatic and symptomatic patients of familial FTLD. In addition, PET imaging with the 11C-MP4A has demonstrated reduced acetylcholinesterase (AChE) activity in patients with FTLD, while PET with the 11C-DAA1106 and 11C-PK11195 revealed an increased level of microglial activation associated with neuroinflammation even before the onset of symptoms in familial FTLD. 18F-fluorodeoxyglucose (FDG)-PET indicated hypometabolism in FTLD with different mutations preceded the atrophy on MRI. Identifying molecular imaging biomarkers for familial FTLD is important for the in-vivo assessment of underlying pathophysiological changes with disease progression and future disease-modifying therapy. We review the recent progress of molecular imaging in familial FTLD with focused on the possible implication of these techniques and their prospects in specific mutation types.
Collapse
Affiliation(s)
- Ruihan Wang
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, China
| | - Hui Gao
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, China
| | - Hongsheng Xie
- Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, China
| | - Zhiyun Jia
- Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, China
| | - Qin Chen
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, China
- *Correspondence: Qin Chen
| |
Collapse
|