Epidemiology of dementia.Ann Med Interne (Paris). 1998 Jun; 149(4):181-6.AM
With an unprecedented demographic change in the world population, the prevention and effective treatment of age-dependent diseased has become a compelling need. Epidemiology contributes in this way by estimating the incidence and prevalence of specific categories of morbidity and by identifying the risk or protective factors of dementia. An integrative analysis of 47 surveys across 17 countries has suggested approximate rates under 1% for dementia from any cause in persons aged 60 to 69 years, rising to about 39% in persons 90 to 95 years old. The prevalence doubles with every five years of age within that range, with few differences taking into account secular changes, age, gender, place of living... Risks factors of vascular dementia are well known. Worldwide epidemiological surveys allow to differentiate "confirmed risk factors" of Alzheimer's type dementia (age, family history, Apolipoprotein E epsilon 4 genotype and Down's syndrome), "possible risk factors" (head injury, aluminum, previous depression...) and "protective factors" (education, anti-inflammatory drugs and estrogen replacement...).