Predementia constructs: mild cognitive impairment or mild neurocognitive disorder? A narrative review Running title: MCI or mild neurocognitive disorder? Félix Bermejo-Pareja 1,2 , Israel Contador 3 , Teodoro del Ser 4 , Javier Olazarán 5 , Sara Llamas-Velasco 1 , Saturio Vega 6 , Julián Benito-León 1 1 Research Institute (Imas12). University Hospital “12 de Octubre”. Madrid. Spain 2 Emeritus Professor. Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED). Carlos III Institute of Health, Madrid. Spain. 3 Department of Basic Psychology, Psychobiology and Methodology of Behavioral Science, University of Salamanca. Salamanca. Spain. 4 Alzheimer’s disease investigation research unit, CIEN Foundation, Carlos III Institute of Health, Queen Sofia Foundation Alzheimer Research. Madrid. Spain 5 Department of Neurology. University Hospital “Gregorio Marañón”. Madrid. Spain. 6 Arévalo Health Center, Arévalo. Ávila, Spain. Conflict of interest: Nothing to declare Author’s funding: Sara Llamas MD, PhD, is currently supported by the Juan Rodés grant, Carlos III Institute of Health, Spain. Key words: predementia, mild cognitive impairment, mild neurocognitive disorder, dementia conversion, vascular cognitive impairment, Alzheimer’s disease, aging, biomarkers, psychometric tests, epidemiology. Word count: Abstract: 250; Text: 4,351; References: 150; 5 tables; 0 figure. Corresponding author: Félix Bermejo-Pareja, MD, PhD Research Institute (Imas12). University Hospital “12 de Octubre”. Avenida de Córdoba s/n. Madrid 28001. Spain Email: fbermejop2013@yahoo.es (better); fbermejop@h12o (institutional email) ORCID: 0000-0002-5413-232X Accepted Article This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/gps.5474. This article is protected by copyright. All rights reserved.