The number of people with dementia globally is estimated to be 50 million. Currently, this is greater than the total population of Spain and is projected to nearly triple by 2050.

Page last reviewed: 05/07/2018

Source: Dementia fact sheet December 2017; World Health Organisation

Source: Prince, M et al (2015). World Alzheimer’s Report 2015, The Global Impact of Dementia: An analysis of prevalence, incidence, cost and trends. Alzheimer’s Disease International

Source: Dementia fact sheet December 2017; World Health Organisation

The global picture of dementia prevalence is complex and affected by a variety of different factors, from life expectancy to quality of health data reporting. Here you can see how these different factors interact based on regional and income boundaries.

Source: Prince, M et al (2015). World Alzheimer’s Report 2015, The Global Impact of Dementia: An analysis of prevalence, incidence, cost and trends. Alzheimer’s Disease International

Source: Prince, M et al (2015). World Alzheimer’s Report 2015, The Global Impact of Dementia: An analysis of prevalence, incidence, cost and trends. Alzheimer’s Disease International

The majority of people with dementia worldwide live in middle income countries and the number is projected to grow both absolutely and as a proportion of global prevalence.

The change in the numbers of people with dementia is expected to increase far more rapidly in the upper middle, lower middle and low income countries than in the high income countries. Even in these high income countries, the number of people is expected to more than double.

Source: Prince, M et al (2015). World Alzheimer’s Report 2015, The Global Impact of Dementia: An analysis of prevalence, incidence, cost and trends. Alzheimer’s Disease International

Source: Prince, M et al (2015). World Alzheimer’s Report 2015, The Global Impact of Dementia: An analysis of prevalence, incidence, cost and trends. Alzheimer’s Disease International

Low income countries tend to have a lower life expectancy, which reduces the prevalence of dementia. In upper middle income countries, life expectancy and populations are increasing, leading to a greater number of people with dementia. High income countries have broadly already experienced the increases in health and population that these upper middle income countries are undergoing and so prevalence is high but will not rise as rapidly.

Source: Prince, M et al (2015). World Alzheimer’s Report 2015, The Global Impact of Dementia: An analysis of prevalence, incidence, cost and trends. Alzheimer’s Disease International

The geographic picture of global dementia prevalence is more complex due to the considerable differences between countries in the same global region which is why, in the graph below, there is less variation between the regions.

The number of people with dementia is expected to rise more rapidly in Asia compared to the rest of the world due to the rapidly rising population.

Source: Prince, M et al (2015). World Alzheimer’s Report 2015, The Global Impact of Dementia: An analysis of prevalence, incidence, cost and trends. Alzheimer’s Disease International