Abstract
Background
Mild Cognitive Impairment (MCI) represents a significant risk factor for dementia but there are only a few Italian population studies on its prevalence and its rate of conversion to dementia.
Aims
Aim of this study was to assess the prevalence of MCI, its subtypes, and rates of conversion to dementia 1 year later in an elderly Italian population.
Methods
The data are based on an Italian multicenter population-based cohort study with both cross-sectional and longitudinal components. Two thousand three hundred thirty-seven individuals over 65 underwent screening, clinical confirmation and 1-year follow-up.
Results
The prevalence of MCI was 21.6% and the amnestic multiple domain was the most frequent subtype (63.2%). The conversion rate to dementia was 4.1% and was found only in the amnestic multiple domain and in the unclassifiable subjects, persons with cognitive deficit but neither demented nor with MCI.
Discussion
The prevalence of MCI in this population sample was similar to that found in other population studies using Petersen’s modified MCI criteria as well as his original criteria. With regard to conversion to dementia, our results emphasize the importance to better classify the unclassifiable subjects at high risk of progression to dementia and also at risk of being undiagnosed and untreated.
Conclusion
MCI is characterized by extreme variability and instability. Data on the prevalence and the rate of conversion from MCI to dementia are difficult to compare given the important differences from study to study especially with regard to the diagnostic criteria utilized and their operationalization.
Similar content being viewed by others
References
Andrieu S, Coley N, Aisen P et al (2009) Methodological issues in primary prevention trials for neurodegenerative dementia. J Alzheimers Dis 16:235–270
Geda YE (2012) Mild cognitive impairment in older adults. Curr Psychiatry Rep 14:320–327
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. J Intern Med 256:240–246
Petersen RC (2004) Mild cognitive impairment as a diagnostic entity. J Intern Med 256:183–194
Petersen RC (2016) Mild cognitive impairment. Continuum (Minneap Minn) 22:404–418
Roberts R, Knopman DS (2013) Classification and epidemiology of MCI. Clin Geriatr Med 29:753–772
Matthews FE, Stephan BC, McKeith IG et al (2008) Medical research council cognitive function and ageing study. Two-year progression from mild cognitive impairment to dementia: to what extent do different definitions agree? J Am Geriatr Soc 56:1424–1433
Petersen RC, Roberts RO, Knopman DS et al (2009) Mild cognitive impairment: ten years later. Arch Neurol 66:1447–1455
Bruscoli M, Lovestone S (2004) Is MCI really just early dementia? A systematic review of conversion studies. Int Psychogeriatr 16:129–140
Ganguli M, Snitz BE, Saxton JA et al (2011) Outcomes of mild cognitive impairment by definition: a population study. Arch Neurol 68:761–767
Ward A, Arrighi HM, Michels S, Cedarbaum JM (2012) Mild cognitive impairment: disparity of incidence and prevalence estimates. Alzheimers Dement 8:14–21
Folstein MF, Folstein SE, McHugh PR (1975) “Mini-mental state”. A practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res 12:189–198
Sunderland T, Hill JL, Mellow AM et al (1989) Clock drawing in Alzheimer’s disease: a novel measure of dementia severity. J Am Geriatr Soc 37:725–729
Katz S, Downs TD, Cash HR et al (1970) Progress in development of the index of ADL. Gerontologist 10:20–30
Lawton MP, Brody EM (1969) Assessment of older people: Self-maintaining and instrumental activities of daily living. Gerontologist 9:179–186
Radloff LS (1977) The CES-D Scale: a self-report depression scale for research in the general population. Appl Psychol Meas 1:385–401
Pfeffer RI, Kurosaki TT, Harrah CH Jr et al (1982) Measurement of functional activities in older adults in the community. J Gerontol 37:323–329
Richards M, Marder K, Bell K et al (1991) Interrater reliability of extrapyramidal signs in a group assessed for dementia. Arch Neurol 48:1147–1149
Hughes CP, Berg L, Danziger WL et al (1982) A new clinical scale for the staging of dementia. Br J Psychiatry 140:566–572
Fioravanti M, Nacca D, Buckley AE et al (1994) The Italian version of the Alzheimer’s disease assessment scale (ADAS): psychometric and normative characteristics from a normal aged population. Arch Gerontol Geriatr 19:21–30
Caffarra C, Vezzadini G, Dieci F et al (2002) Rey–Osterrieth complex figure: normative values in an Italian population sample. Neurol Sci 22:443–447
Carlesimo GA, Caltagirone C, Gainotti G (1996) The mental deterioration battery: normative data, diagnostic reliability and qualitative analyses of cognitive impairment. The group for the standardization of the mental deterioration battery. Eur Neurol 36:378–384
Novelli G, Papagno C, Capitani E et al (1986) Tre test clinici di ricerca e produzione lessicale. Taratura su soggetti normali. Archivio di Psicologia, Neurologia e Psichiatria 47:477–506
Semenza C, Borgo F, Mondini S et al (2000) Proper names in the early stages of Alzheimer’s disease. Brain Cogn 43:384–387
Spinnler H, Tognoni G (1987) Standardizzazione e taratura italiana di test neuropsicologici. Ital J Neurol Sci suppl 8–6:1–120
Amodio P, Wenin H, Del Piccolo F et al (2002) Variability of trail making test, symbol digit test and line trait test in normal people. A normative study taking into account age-dependent decline and sociobiological variables. Aging Clin Exp Res 14:117–131
American Psychiatric Association (1994) Diagnostic and statistical manual of mental disorders (DSM-IV), 4th edn. American Psychiatric Association, Washington
Dlugaj M, Weimar C, Wege N et al (2010) Heinz Nixdorf Recall Study Investigative Group. Prevalence of mild cognitive impairment and its subtypes in the Heinz Nixdorf Recall study cohort. Dement Geriatr Cogn Disord 30:362–373
Di Carlo A, Lamassa M, Baldereschi M et al (2007) CIND and MCI in the Italian elderly: frequency, vascular risk factors, progression to dementia. Neurology 68:1909–1916
Moretti F, De Ronchi D, Palmer K et al (2013) Prevalence and characteristics of mild cognitive impairment in the general population. Data from an Italian population-based study: the Faenza project. Aging Ment Health 17:267–275
Ravaglia G, Forti P, Montesi F et al (2008) Mild cognitive impairment: epidemiology and dementia risk in an elderly Italian population. J Am Geriatr Soc 56:51–58
Stephan BC, Brayne C, McKeith IG et al (2008) Medical research council cognitive function and ageing study. Mild cognitive impairment in the older population: who is missed and does it matter? Int J Geriatr Psychiatry 23:863–871
Train the Brain Consortium (2017) Randomized trial on the effects of a combined physical/cognitive training in aged MCI subjects: the Train the Brain study. Sci Rep 3:39471. doi:10.1038/srep39471.
Ngandu T, Lehtisalo J, Solomon A et al (2015) A 2 year multidomain intervention of diet, exercise, cognitive training, and vascular risk monitoring versus control to prevent cognitive decline in at-risk elderly people (FINGER): a randomized controlled trial. Lancet 385:2255–2263
Fiatarone Singh MA, Gates N, Saigal N et al (2014) The Study of Mental and Resistance Training (SMART) study—resistance training and/or cognitive training in mild cognitive impairment: a randomized, double-blind, double-sham controlled trial. J Am Med Dir Assoc 15:873–880
Yaffe K, Middleton LE, Lui LY et al (2011) Mild cognitive impairment, dementia, and their subtypes in oldest old women. Arch Neurol 68:631–636
Barnes DE, Yaffe K (2011) The projected effect of risk factor reduction on Alzheimer’s disease prevalence. Lancet Neurol 10:819–828
Litvan I, Aarsland D, Adler CH et al (2011) MDS Task Force on mild cognitive impairment in Parkinson’s disease: critical review of PD-MCI. Mov Disord 26:1814–1824
Goveas JS, Rapp SR, Hogan PE et al (2016) Predictors of optimal cognitive aging in 80+ women: the women’s health initiative memory study. J Gerontol A Biol Sci Med Sci 71:S62–S71
Lenehan ME, Klekociuk SZ, Summers MJ (2012) Absence of a relationship between subjective memory complaint and objective memory impairment in mild cognitive impairment (MCI): is it time to abandon subjective memory complaint as an MCI diagnostic criterion. Int Psychogeriatr 24:1505–1514
Acknowledgements
This study was supported by a Special Program of the Ministry of Health (Special program ex art. 12, comma 2, lett B D.Lvo n. 502/92). We would like to thank the Scientific Coordinators of the Dementia Registry Study Group: Dr. Carla Grasselli, Dr. Renzo Rozzini, Dr. Salvatore Bonaiuto, Dr. Domenico Cucinotta. Thanks to Linda Inverso Moretti for assistance in editing the manuscript.
Author information
Authors and Affiliations
Consortia
Corresponding author
Ethics declarations
Conflict of interest
FL, PS, MN, GC work with SM, Editor in Chief of the Aging Clinical and Experimental Research.
Ethical approval
The study was approved by the ethics committees of the local health units of the participating centers.
Informed consent
All participants gave written informed consent.
Additional information
F. Limongi and P. Siviero contributed equally to the manuscript.
Rights and permissions
About this article
Cite this article
Limongi, F., Siviero, P., Noale, M. et al. Prevalence and conversion to dementia of Mild Cognitive Impairment in an elderly Italian population. Aging Clin Exp Res 29, 361–370 (2017). https://doi.org/10.1007/s40520-017-0748-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s40520-017-0748-1