MILD COGNITIVE IMPAIRMENT (MCI)
The term Mild Cognitive Impairment (MCI) refers to a clinical syndrome characterized by the presence of a subtle cognitive deficit, not related to physiological age associated cognitive modification, in a non demented person. The deficit can involve one or more cognitive functions and has a minimal impact on autonomy in daily life. The clinical criteria widely used for the diagnosis of MCI in research and clinical settings have been the Mayo Clinic criteria . This first criteria of MCI were focused on memory problems and detailed what today is called amnestic-MCI. More general criteria for MCI syndrome, less focused on memory impairment and broadened to include impairment in other areas of cognitive functioning, have been defined by Mayo clinic . To better characterize MCI spectrum an international consensus conference was held in 2003 and revised core criteria were defined  that are useful to characterize different subtype of MCI: amnestic or non-amnestic (e.g. executive functions impairment, language impairment or attention impairment) single domain MCI, amnestic or non-amnestic multiple domains MCI. For the DECI project the most recent clinical criteria for MCI, proposed by Albert et al. , will be used:
- Concern regarding a change in cognition – There should be evidence of concern about a change in cognition, in comparison with the person’s previous level. This concern can be obtained from the patient, from an informant who knows the patient well, or from a skilled clinician observing the patient
- Impairment in one or more cognitive domains – There should be evidence of lower performance in one or more cognitive domains that is greater than would be expected for the patient’s age and educational background (objective evidence of impairment in single or multiple cognitive domains, with scores falling at least 1.5 standard deviations below age-matched norms and in reference to the individuals educational and socioeconomic background). If repeated assessments are available, then a decline in performance should be evident over time. This change can occur in a variety of cognitive domains, including memory, executive function, attention, language, and visuospatial skills. An impairment in episodic memory (i.e., the ability to learn and retain new information) is seen most commonly in MCI patients who subsequently progress to a diagnosis of AD dementia.
- Preservation of independence in functional abilities – Persons with MCI commonly have mild problems performing complex functional tasks which they used to perform previously, such as paying bills, preparing a meal, or shopping. They may take more time, be less efficient, and make more errors at performing such activities than in the past. Nevertheless, they generally maintain their independence of function in daily life, with minimal aids or assistance. It is recognized that the application of this criterion is challenging, as it requires knowledge about an individual’s level of function at the current phase of their life. However, it is noteworthy that this type of information is also necessary for the determination of whether a person is demented.
- Non demented – These cognitive changes should be sufficiently mild that there is no evidence of a significant impairment in social or occupational functioning. It should be emphasized that the diagnosis of MCI requires evidence of intraindividual change. If an individual has only been evaluated once, change will need to be inferred from the history and/or evidence that cognitive performance is impaired beyond what would have been expected for that individual. Serial evaluations are of course optimal, but may not be feasible in a particular circumstance
Dementia is a term that describes chronic and progressive dysfunction of cognitive and functional abilities due to a pathology of cortical and/or sub-cortical brain structures. These cognitive and functional changes are commonly accompanied by disturbances of mood, behaviour, and personality. The DSM – IV and DMS-IV TR have no general criteria for Dementia syndrome but only specific criteria for Dementia dues to a particular etiology (e.g. Alzheimer dementia, Vascular Dementia, and so on). For the DECI project the recent clinical criteria for dementia proposed by the DSM V will be used . The DSM V have general criteria for dementia. In the manual dementia is defined as “Major cognitive disorder” and the diagnostic criteria are:
- Evidence of significant cognitive decline from a previous level of performance in one or more cognitive domains (complex attention, executive function, learning and memory, language, perceptual-motor, or social cognition) based on:
- Concern of the individual, a knowledgeable informant, or the clinician that there has been a significant decline in cognitive function; and
- A substantial impairment in cognitive performance, preferably documented by standardized neuropsychological testing or, in its absence, another quantified clinical assessment.
- The cognitive deficits interfere with independence in everyday activities (i.e., at a minimum, requiring assistance with complex instrumental activities of daily living such as paying bills or managing medications).
- The cognitive deficits do not occur exclusively in the context of a delirium
- The cognitive deficits are not better explained by another mental disorder (e.g., major depressive disorder, schizophrenia).
ICD – 10 diagnostic criteria for Dementia (for research) are also widely used and accepted but less simple to use .
G1.: Evidence of each of the following
- A decline in memory, which is most evident in the learning of new information, although in more severe cases, the recall of previously learned information may be also affected. The impairment applies to both verbal and non-verbal material. The decline should be objectively verified by obtaining a reliable history from an informant, supplemented, if possible, by neuropsychological tests or quantified cognitive assessments. The severity of the decline, with mild impairment as the threshold for diagnosis, should be assessed as follows:
- Mild: a degree of memory loss sufficient to interfere with everyday activities, though not so severe as to be incompatible with independent living. The main function affected is the learning of new material. For example, the individual has difficulty in registering, storing and recalling elements in daily living, such as where belongings have been put, social arrangements, or information recently imparted by family members.
- Moderate: A degree of memory loss which represents a serious handicap to independent living. Only highly learned or very familiar material is retained. New information is retained only occasionally and very briefly. The individual is unable to recall basic information about where he lives, what he has recently been doing, or the names of familiar persons.
- Severe: a degree of memory loss characterized by the complete inability to retain new information. Only fragments of previously learned information remain. The subject fails to recognize even close relatives.
- A decline in other cognitive abilities characterized by deterioration in judgment and thinking, such as planning and organizing, and in the general processing of information. Evidence for this should be obtained when possible from interviewing an informant, supplemented, if possible, by neuropsychological tests or quantified objective assessments. Deterioration from a previously higher level of performance should be established. The severity of the decline, with mild impairment as the threshold for diagnosis, should be assessed as follows:
- Mild. The decline in cognitive abilities causes impaired performance in daily living, but not to a degree making the individual dependent on others. More complicated daily tasks or recreational activities cannot be undertaken.
- Moderate. The decline in cognitive abilities makes the individual unable to function without the assistance of another in daily living, including shopping and handling money. Within the home, only simple chores are preserved. Activities are increasingly restricted and poorly sustained.
- Severe. The decline is characterized by an absence, or virtual absence, of intelligible ideation. The overall severity of the dementia is best expressed as the level of decline in memory or other cognitive abilities, whichever is the more severe (e.g. mild decline in memory and moderate decline in cognitive abilities indicate a dementia of moderate severity).
Preserved awareness of the environment (i.e. absence of clouding of consciousness (as defined in F05, criterion A) during a period of time long enough to enable the unequivocal demonstration of G1. When there are superimposed episodes of delirium the diagnosis of dementia should be deferred.
A decline in emotional control or motivation, or a change in social behavior, manifest as at least one of the following:
- emotional ability;
- Coarsening of social behaviour.
G4. For a confident clinical diagnosis, G1 should have been present for at least six months; if the period since the manifest onset is shorter, the diagnosis can only be tentative.
 Petersen, R.C., Smith, G.E., Waring, S.C., et al. (1999). Mild cognitive impairment: clinical characterization and outcome. Archives of Neurology, 56, 303–308.
 Petersen, R.C. (2004). Mild cognitive impairment as a diagnostic entity. Journal of Internal Medicine, 256, 183–194
 Winblad, B., Palmer, K., Kivipelto, M., et al. (2004). Mild cognitive impairment: beyond controversies, towards a consensus: report of the International Working Group on Mild Cognitive Impairment. Journal of Internal Medicine, 256, 240–246
 Albert, M.S., DeKosky, S.T., Dickson, D., et al. (2011). The diagnosis of mild cognitive impairment due to Alzheimer’s disease: recommendations from the National Institute on Aging – Alzheimer’s Association workgroups on diagnostic guidelines for Alzheimer’s disease. Alzheimers and Dementia, 7, 270–279
 American Psychiatric Association (2013). DSM-V: Diagnostic and Statistical Manual of Mental Disorders, 5th ed. Washington, DC: American Psychiatric Association.
[10 World Health Organization (1992). The ICD–10 Classification of Mental and Behavioural Disorders: Clinical Descriptions and Diagnostic Guidelines. WHO.