title: [A review of the construct of mild cognitive impairment: general aspects].
abstract: BACKGROUND
  The term 'mild cognitive impairment' (MCI) indicates an initial state in the process of developing dementia which is considered by some to be an early stage of dementia -especially of the Alzheimer type- while others see it as an independent condition. It is therefore necessary and important to reach a suitable diagnosis, by means of reliable and sensitive instruments and techniques, which make it possible to discriminate between subjects undergoing normal ageing and those with pathological ageing.
  
  
  CONCLUSIONS
  The aim of this work is to offer a general overview of this construct. First of all the term and its meaning are put into a historical context. The article also describes its subtypes and the diagnostic criteria employed and defined by Petersen -which are considered to be the most widely used- as well as those of other authors. To do so, the epidemiological data (incidence/prevalence) that have appeared in different studies are cited and the main (biological, psychological, behavioural and neuropsychological) markers of the progression of MCI towards dementia are outlined. In the following subsection, the process used to evaluate MCI is shown. The steps or stages that must be followed in order to perform a suitable diagnosis of this condition are also described. The article ends with some final considerations, where the most significant facts from this review are discussed.
authors.affiliation: Universidad de Salamanca, Facultad de Psicologia, 37005 Salamanca, Espana. jlsanch@usal.es
authors.forename: J L
authors.initials: JL
authors.lastname: Sanchez-Rodriguez
authors.forename: C
authors.initials: C
authors.lastname: Torrellas-Morales
mesh_terms: D015415:Biomarkers; D003072:Cognition Disorders / Q000145:classification / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D003704:Dementia / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D018450:Disease Progression; D006801:Humans; D009483:Neuropsychological Tests; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers