Episodic and working memory function in Primary Progressive Aphasia: A meta-analysis
Willem S Eikelboom, Nikki Janssen, Lize C Jiskoot, Esther van den Berg, Ardi Roelofs, Roy P C Kessels, Willem S Eikelboom, Nikki Janssen, Lize C Jiskoot, Esther van den Berg, Ardi Roelofs, Roy P C Kessels
Abstract
Objective: The distinction between Primary Progressive Aphasia (PPA) variants remains challenging for clinicians, especially for the non-fluent (nfv-PPA) and the logopenic variants (lv-PPA). Previous research suggests that memory tests might aid this differentiation. This meta-analysis compares memory function among PPA variants.
Method: Effects sizes were extracted from 41 studies (N = 849). Random-effects models were used to compare performance on episodic and working memory tests among PPA patients and healthy controls, and between the PPA variants.
Results: Memory deficits were frequently observed in PPA compared to controls, with large effect sizes for lv-PPA (Hedges' g = -2.04 [-2.58 to -1.49]), nfv-PPA (Hedges' g = -1.26 ([-1.60 to -0.92], p < .001)), and the semantic variant (sv-PPA; Hedges' g = -1.23 [-1.50 to -0.97]). Sv-PPA showed primarily verbal memory deficits, whereas lv-PPA showed worse performance than nfv-PPA on both verbal and non-verbal memory tests.
Conclusions: Memory deficits were more pronounced in lv-PPA compared to nfv-PPA. This suggests that memory tests may be helpful to distinguish between these PPA variants.
Keywords: Frontotemporal dementia; Logopenic aphasia; Memory; Meta-analysis; Primary progressive aphasia; Progressive nonfluent aphasia; Semantic dementia; Systematic review.
Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Source: PubMed