Prevalence of mild cognitive impairment in 60- to 64-year-old community-dwelling individuals: The Personality and Total Health through Life 60+ Study

Dement Geriatr Cogn Disord. 2005;19(2-3):67-74. doi: 10.1159/000082351. Epub 2004 Nov 29.

Abstract

This epidemiological study aimed at determining the prevalence of mild cognitive impairment (MCI) in 60- to 64-year-old individuals using different diagnostic criteria. Community dwelling individuals (n = 2,551) in the age range of 60-64 years were recruited randomly through the electoral roll. They were screened using the MMSE and a short cognitive battery, and those who screened positive underwent detailed medical and cognitive assessments. Extant MCI-related diagnoses were established by consensus. Predictive regression models on the sub-sample were used to determine population prevalence for the diagnoses. Of the 224 subjects who screened positive for MCI, 112 underwent a detailed assessment and 74% met the criteria for at least one recognised diagnosis of mild cognitive deficit (MCI and related diagnoses). By predictive regression modelling, the prevalence of any MCI diagnosis was 13.7% (95% CI 9.1-30.2) in the population of 60- to 64-year-olds. The estimated prevalence rates for specific diagnoses were: MCI 3.7%, ageing-associated cognitive decline 3.1%, Clinical Dementia Rating score (0.5) 2.8%, age-associated memory impairment 1%, other cognitive disorders 0.9%, and mild neurocognitive disorder 0.6%. Agreement on 'caseness' between various proposed diagnoses was at best fair and generally poor. Memory and other cognitive problems not meeting the threshold for dementia are relatively common in 60- to 64-year-old individuals living in the community. The prevalence rate varies up to six-fold according to the diagnostic criteria applied, with limited overlap between diagnoses. There is an urgent need for standardization of the criteria.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activities of Daily Living / psychology
  • Aged
  • Amnesia / diagnosis
  • Amnesia / epidemiology
  • Amnesia / psychology
  • Cognition Disorders / diagnosis
  • Cognition Disorders / epidemiology*
  • Cognition Disorders / psychology
  • Cross-Sectional Studies
  • Dementia / diagnosis
  • Dementia / epidemiology*
  • Dementia / psychology
  • Female
  • Health Status*
  • Humans
  • Incidence
  • Male
  • Mass Screening
  • Middle Aged
  • Neuropsychological Tests / statistics & numerical data*
  • New South Wales
  • Personality Assessment / statistics & numerical data*
  • Reference Values