Abstract

Introduction: Alzheimer's disease (AD) has classically been considered to present typical cognitive symptoms and neuroanatomical changes. However, the neurobiological basis of some clinical phenotypes of AD is similar to that of frontotemporal dementia (FTD). Therefore, the heterogeneity of these diseases leads to uncertain evaluation and diagnosis processes, due to limited understanding of the associated neurocognitive symptoms. This systematic review aims to describe neuropsychological characteristics and similarities in patients with AD and FTD, and to identify critical points for their differential diagnosis. Methods: The present study followed the PRISMA guidelines and included studies from the PubMed, Scopus, and Web of Science databases, published between 2005 and 2020. Results: The search returned a total of 41 articles eligible for critical analysis. The available evidence points to key differences in such cognitive domains as language (eg, verbal fluency), memory, social cognition, executive functioning, and behaviour; these should be considered in all neuropsychological assessments and diagnostic processes. Conclusion: Such language domains as verbal fluency (semantic and phonemic) and semantic/grammar alterations seem to be useful markers for differential diagnosis between AD and FTD.