Cent Eur J Public Health 2015, 23(4):365-367 | DOI: 10.21101/cejph.a4414

Is Mild Cognitive Impairment a Precursor of Alzheimer's Disease? Short Review

Jana Janoutová1, Omar Šerý2, Ladislav Hosák3, Vladimír Janout1
1 Department of Epidemiology and Public Health, Faculty of Medicine, Ostrava University in Ostrava, Ostrava, Czech Republic
2 Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Brno, Czech Republic
3 Department of Psychiatry, Charles University in Prague, School of Medicine in Hradec Králové and University Hospital Hradec Králové, Hradec Králové, Czech Republic

Mild Cognitive Impairment (MCI) may be a precursor of Alzheimer's disease (AD). There is a boundary area between normal aging and dementia. In practice, the term "age related cognitive decline" has been used interchangeably with "normal aging". Alternatively, the term "aging associated cognitive decline" was introduced and defined by a performance on a standardized cognitive scale focused on learning and memory, attention and cognitive speed, language, or visuoconstructional abilities. The term "mild cognitive impairment" was adopted by Petersen in 2004 to describe a period in the course of neurodegenerative disease where cognition is no longer normal relative to age expectations, however, daily functions are not sufficiently disrupted to correlate with the diagnosis of dementia. Most of the literature refers to the amnestic form of MCI, which is likely a precursor of AD. The rate of conversion from amnestic form of MCI to AD is estimated to reach 10-15% per year. That is why MCI generated a great deal of research. When considering MCI a precursor of AD, it seems reasonable to study AD genetic markers in the MCI patients. In AD, association studies focus on genetic polymorphisms assumed to have an effect on the expression and modulation function of genes associated with AD pathogenesis (ApoE, APP, presenilin 1, presenilin 2, tau protein), and on polymorphisms related to metabolism of the aforementioned proteins (splicing, degradation). Neuropsychological assesment plays a substantial role in the diagnosis of MCI, especially in the case of identification of different MCI subtypes or typical profiles of cognitive performance in prodromal phases of neurodegenerative diseases. The optimal composition of diet may increase an average age and prevent impairment of cognitive functions at the same time. Despite the progress in early diagnosis of MCI and dementia, further research is needed on differential diagnosis and treatment. In amnestic subtype of MCI some genetic markers may already be present, predicting possible future development of AD. Pointing to the need of secondary prevention, lifestyle modifications and possible early treatment could be implemented.

Keywords: mild cognitive impairment, Alzheimer's dementia, terminology, genetics, neuropsychological testing, secondary prevention

Received: April 29, 2015; Revised: December 7, 2015; Accepted: December 7, 2015; Published: December 30, 2015  Show citation

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Janoutová J, Šerý O, Hosák L, Janout V. Is Mild Cognitive Impairment a Precursor of Alzheimer's Disease? Short Review. Cent Eur J Public Health. 2015;23(4):365-367. doi: 10.21101/cejph.a4414. PubMed PMID: 26841152.
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References

  1. Caccappolo-van Vliet E, Miozzo M, Marder K, Stern Y. Where do perseverations come from? Neurocase. 2003 Aug;9(4):297-307. Go to original source... Go to PubMed...
  2. Mild cognitive impairment (MCI) [Internet]. Rochester (MN): Mayo Foundation for Medical Education and Research; 2012 [cited 2015 Nov 5].Available from: http://www.mayoclinic.org/diseases-conditions/mildcognitive-impairment/basics/definition/con-20026392.
  3. Levy R. Aging-associated cognitive decline. Working Party of the International Psychogeriatric Association in collaboration with the World Health Organization. Int Psychogeriatr. 1994;6(1):63-8. Erratum in: Int Psychogeriatr 1994;6(2):133. Go to original source...
  4. Pantel J, Kratz B, Essig M, Schröder J. Parahippocampal volume deficits in subjects with aging-associated cognitive decline.Am J Psychiatry. 2003 Feb;160(2):379-82. Go to original source... Go to PubMed...
  5. Petersen RC. Mild cognitive impairment as a diagnostic entity. J Intern Med. 2004 Sep;256(3):183-94. Go to original source... Go to PubMed...
  6. Petersen RC, Morris JC. Mild cognitive impairment as a clinical entity and treatment target. Arch Neurol. 2005 Jul;62(7):1160-3; discussion 1167. Go to original source... Go to PubMed...
  7. Sheardová K. Mild cognitive impairment in clinical practice. Psychiatr Praxi. 2010;11(2):62-5. (In Czech.)
  8. Šerý O, Povová J, Míšek I, Pešák L, Janout V. Molecular mechanisms of neuropathological changes in Alzheimer's disease: a review. Folia Neuropathol. 2013;51(1):1-9. Go to original source... Go to PubMed...
  9. Nikolaj T, Bezdíčk O, Vyhnálek M, Hort J. Mild cognitive impairment: diagnostic unit or stadium preceding dementia? Českoslov Psychol. 2012;56(4):374-90. (In Czech.)
  10. Raboch J. Cognitive functions, aging and dietary habits. Čes Slov Psychiatr. 2010;106(2):81-6. (In Czech.)
  11. Jirák R. Old and new diagnostic criteria for Alzheimer's disease in the conditions of the Czech Republic. Neurol Praxi. 2011;12(2):135-7. (In Czech.)
  12. Merchant C, Tang MX, Albert S, Manly J, Stern Y, Mayeux R. Influence of smoking on the risk of Alzheimer's disease. Neurology. 1999 Apr 22;52(7):1408-12. Go to original source... Go to PubMed...
  13. Peters R, Poulter R, Warner J, Beckett N, Burch L, Bulpitt C. Smoking, dementia and cognitive decline in the elderly, a systematic review. BMC Geriatr. 2008 Dec 23;8:36. Go to original source... Go to PubMed...
  14. Smith GE, Bondi MW, editors. Mild cognitive impairment and dementia: definitions, diagnosis, and treatment. NewYork: Oxford University Press; 2013.
  15. Clark LR, Schiehser DM, Weissberger GH, Salmon DP, Delis DC, Bondi MW. Specific measures of executive function predict cognitive decline in older adults. J Int Neuropsychol Soc. 2012 Jan;18(1):118-27. Go to original source... Go to PubMed...