Age-Stratified Prevalence of Mild Cognitive Impairment and Dementia in European Populations: A Systematic Review

The prevalence of mild cognitive impairment (MCI) and dementia according to age remain uncertain. We systematically extracted age-stratified estimates of MCI and dementia prevalence reported in European studies published since 1995, and performed meta-analyses for dementia. We identified 10 relevant studies on MCI and 26 studies on dementia. Studies on MCI presented substantial heterogeneity preventing a meta-analysis, with a majority reporting an increase in prevalence at ≥75 years old. Pooled prevalence of dementia rose continuously from 55 years of age, reaching 44.7% (39.8; 49.6) in those ≥95 years of age. Homogenization of MCI criteria, and additional studies in Northern European population would be warranted.