Longitudinal Changes in Cognition, Behaviours, and Functional Abilities in the Three Main Variants of Primary Progressive Aphasia: A Literature Review

Abstract

Primary progressive aphasias (PPAs) are a group of neurodegenerative diseases presenting with insidious and relentless language impairment. Three main PPA variants have been described: the non-fluent/agrammatic variant (nfvPPA), the semantic variant (svPPA), and the logopenic variant (lvPPA). At the time of diagnosis, patients and their families’ main question pertains to prognosis and evolution, but very few data exist to support clinicians’ claims. The objective of this study was to review the current literature on the longitudinal changes in cognition, behaviours, and functional abilities in the three main PPA variants. A comprehensive review was undertaken via a search on PUBMED and EMBASE. Two authors independently reviewed a total of 65 full-text records for eligibility. A total of 14 group studies and one meta-analysis were included. Among these, eight studies included all three PPA variants. Eight studies were prospective, and the follow-up duration was between one and five years. Overall, svPPA patients showed more behavioural disturbances both at baseline and over the course of the disease. Patients with lvPPA showed a worse cognitive decline, especially in episodic memory, and faster progression to dementia. Finally, patients with nfvPPA showed the most significant losses in language production and functional abilities. Data regarding the prodromal and last stages of PPA are still missing and studies with a longer follow-up observation period are needed.

Primary progressive aphasia and motor neuron disease: A review

“…As to the median survival of PPA-MND patients – i.e., ≈3 years –, it was slightly lower than that of patients with PPA only ( Montembeault et al, 2018 ), this agreeing with the fact that MN involvement represents a risk factor for a shorter survival in PPA patients ( De La Sablonnière et al, 2021 ; El-Wahsh et al, 2021 ). Its high heterogeneity herewith found might be accounted for by the diversities across both PPA and MND phenotypes – since survival is longer in SD than in PNFA ( Tastevin et al, 2021 ), and shorter in classical ALS as compared to atypical MND variants – such as predominant-UMN phenotypes ( Turner and Talbot, 2020 ), which were relatively highly represented (25.5%) among PPA-MND patients.…”

“…By contrast, little is still known about the pathology, genetics and clinical features of co-occurring primary progressive aphasia (PPA) and MND ( Ulugut et al, 2021 ). In the light of the diagnostic ( Strong et al, 2017 ; Suárez-González et al, 2021 ) and prognostic relevance ( Garcin et al, 2009 ; Ahmed et al, 2020 ; De La Sablonnière et al, 2021 ) of language disorders in MND patients and of motor neuron (MN) dysfunction in PPA patients, the present study aims at systematically reviewing evidence on the co-occurrence between PPA and MND (hereafter referred to as “PPA-MND”).…”

Sex influences clinical phenotype in frontotemporal dementia

“…In the present study, patients fulfilling current clinical criteria for probable FTD [13,19] were consecutively recruited at the Centre for Neurodegenerative Disorders, Department of Clinical and Experimental Sciences, University of Brescia, Italy, from July 2007 to July 2021.…”

Advances in Primary Progressive Aphasia

“…In "Longitudinal Changes in Cognition, Behaviours, and Functional Abilities in the Three Main Variants Primary Progressive Aphasia: A Literature Review" [7], the authors provided a literature review on the natural history of the three main variants of PPA. The review focused on cognitive, behavioral, and functional changes associated with the syndromes.…”