Global Burden of Dementia

The work of the 10/66 Dementia Research Group has substantially updated our understanding of the global prevalence and impact of dementia. The information from prevalence and incidence studies in Latin America, India, and China has been synthesised with new data from other research studies, and used to generate new estimates of numbers affected worldwide, published in ADIs 2009 World Alzheimer Report and the World Health Organizations 2012 report: Dementia: a Public Health Priority 2012. Since 2009, the global evidence base has expended, most particularly with new studies from China and sub-Saharan Africa. The previous numbers have been updated using the new evidence emerging from those 2 regions and were presented in a Policy Brief published before the G8 Dementia Summit held on 11 December 2013.

It is now estimated that in 2013 44.3 million people worldwide were living with dementia, this figure nearly doubling every twenty years to reach 135.5 million by the year 2050. The updated estimates are higher than the original estimates reported in the 2009 World Alzheimer Report, by 15% in 2030 and by 17% in 2050.

• Most people with dementia live in LMIC- 62% in 2013, rising to 66% in 2030 and 71% in 2050.
• By 2050, increases will be much sharper in low and middle income countries (246%), than in high income countries (131%).
• The largest increases in projected numbers of people with dementia are those for the Asia East and sub-Saharan African regions, accounted for by the higher age-specific prevalence of dementia estimated in our new reviews of survey from thse regions.

Well designed epidemiological research can generate awareness, inform policy, and encourage service development. However, such evidence is lacking in many world regions, and patchy in others, with few studies and widely varying estimates.