The complex burden of determining prevalence rates of mild cognitive impairment: A systematic review

Abstract

Mild cognitive impairment (MCI) is a syndrome characterized by a decline in cognitive performance greater than expected for an individual's age and education level, but that does not interfere much with daily life activities. Establishing the prevalence of MCI is very important for both clinical and research fields. In fact, in a certain percentage of cases, MCI represents a prodromal condition for the development of dementia. Accordingly, it is important to identify the characteristics of MCI that allow us to predict the development of dementia. Also, initial detection of cognitive decline can allow the early implementation of prevention programs aimed at counteracting or slowing it down. To this end, it is important to have a clear picture of the prevalence of MCI and, consequently, of the diagnostic criteria used. According to these issues, this systematic review aims to analyze MCI prevalence, exploring the methods for diagnosing MCI that determine its prevalence. The review process was conducted according to the PRISMA statement. Three thousand one hundred twenty-one international articles were screened, and sixty-six were retained. In these studies, which involved 157,035 subjects, the prevalence of MCI ranged from 1.2 to 87%. The review results showed a large heterogeneity among studies due to differences in the subjects' recruitment, the diagnostic criteria, the assessed cognitive domains, and other methodological aspects that account for a higher range of MCI prevalence. This large heterogeneity prevents drawing any firm conclusion about the prevalence of MCI.

COGNITIVE ASSESSMENT WITH COGNIVUECLARITY®: PSYCHOMETRIC PROPERTIES AND ENHANCED NORMATIVE RANGES IN A DIVERSE POPULATION

“…The detection of MCI and AD is limited in community settings [31-33] due in part to the use of brief screening tests of objective cognitive performance that lack psychometric properties similar to those of Gold Standard tests [4,34]. However, Gold Standard tests, such as the RBANS, are lengthy and require specialized staff to administer, score and interpret, making them impractical in the clinic.…”

“…The detection of MCI and AD is limited in community settings [31][32][33] due in part to the use of brief screening tests of objective cognitive performance that lack psychometric properties similar to those of Gold Standard tests [4,34]. However, Gold…”

Redefinition of dementia care in Italy in the era of amyloid-lowering agents for the treatment of Alzheimer’s disease: an expert opinion and practical guideline

“…According to data presented in the ‘Dementia in Europe Yearbook 2019’, the number of people living with dementia in Italy was 1.3 million in 2018 and is expected to raise to 1.4–1.5 million by 2025, 50–70% of which facing AD (i.e., 0.7–1.1 millions) [ 21 , 22 ]. With regard to MCI, many authors reported a prevalence of 15–20% in the general population, with a rate of conversion to dementia of 10–15% per year [ 23 ]. In a 2008 Italian study, the prevalence of MCI in a population over the age of 65 was 7.7% (51% of which of the amnestic type), meaning 1,081,958 people in Italy suffering from MCI (551,799 with the amnestic type) [ 24 ].…”

Episodic and Semantic Autobiographical Memory in Mild Cognitive Impairment (MCI): A Systematic Review

“…The main limitation is that MCI is a varied phenomenon. In a recent systematic review [55], authors highlighted the difficulty of diagnosing MCI. They found that MCI prevalence rates range from 1.2 to 87%.…”