The number of people with dementia is set to triple in 30 years, with 152 million set to be affected globally by 2050, international projections suggest.

The research from the University of Washington School of Medicine was presented at the 2021 Alzheimer’s Association International Conference in Colorado on Tuesday.

Researchers at the University of Washington estimated global dementia prevalence from 1990 to 2019.

The figures suggest that the number of people living with the condition is set to increase from an estimated 57 million in 2019 to 152 million by 2050.

Much of the growth is set to be fuelled in cases from sub-Saharan Africa, north Africa and the Middle East, driven largely by population growth and an ageing population.

Previous research has suggested UK numbers are likely to roughly double over the same period, with two million cases by 2050, compared with around 850,000 now. However, recent data has suggested the increase may be slowing in the UK.

Separately researchers from Maastricht University in the Netherlands estimated that every year there are now around 10 new cases of young-onset dementia – where people develop dementia symptoms under the age of 65 – per 100,000 people.

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This suggests that around 350,000 people worldwide develop young-onset dementia annually,  the scientists said. It means the number of people suffering “early onset” dementia may have doubled in the past two decades.

Hilary Evans, chief executive of Alzheimer’s Research UK, said: “Dementia is our greatest long-term medical challenge. These striking figures [from the latest US research] lay bare the shocking scale of dementia on a global scale.

“To have 57 million people already living with this devastating condition is 57 million too many, but with that number set to almost triple we need to see concerted global action now, to transform the prospects for the next generation.”

She encouraged people to make “positive lifestyle changes” to “help tip the scales in our favour” when it comes to the chances of developing the condition.

She said: “There is robust evidence that what’s good for the heart is also good for the brain. Not smoking, only drinking within the recommended limits, staying mentally and physically active, eating a balanced diet, and keeping blood pressure and cholesterol levels in check can all help to keep our brains healthy as we age.”