Prevalence of dementia in several regions of the world: analysis of epidemiologic studies from 1994 to 2000

OBJECTIVE: To analyse the prevalence studies of dementia from 1994 to 2000. METHODS: The papers were searched on Medline and Lilacs and the inclusion criteria were: to be an original study, that estimated dementia prevalence and investigated community samples. RESULTS: thirty-eight studies were evaluated from all continents. The mean age-specific prevalence rates of dementia were 1,17% for the 65-69 years group, and 54,83% over 95 years. The results were strongly influenced by age. Dementia prevalence rates were higher on women on 75% of the papers reviewed. The Alzheimer's disease/vascular dementia ratio was higher in South America and lower in Asia. DISCUSSION: Methodological advances were found, specially regarding the homogeneity of diagnostic criteria. The effect of age on the rates of dementia prevalence was pronounced, up to 90 years of age.