The number of dementia cases worldwide will triple from 44 million to 135 million by 2050, according to a report from Alzheimer’s Disease International.
The group says increased life expectancy will lead to increased cases of dementia.
"It's a global epidemic and it is only getting worse - if we look into the future the numbers of elderly people will rise dramatically,” said Marc Wortmann, the executive director at Alzheimer Disease International.
The group released their study ahead of the G8 Dementia Summit next week in London. It says most governments are “woefully unprepared for the dementia epidemic.”
Rich countries are home to 38 percent of dementia cases currently, but that is predicted to shift, with 71 percent of patients living in poor and middle-income countries by 2050.
"Dementia is fast becoming the biggest health and social care challenge of this generation," said Jeremy Hughes, chief executive of the UK's Alzheimer's Society. "We must tackle dementia now, for those currently living with the condition across the world and for those millions who will develop dementia in the future."
The group calls for more spending on Alzheimer’s research.
"Increasing numbers of people affected by dementia worldwide is cause for alarm, but research can stem the tide,” said chief executive of Alzheimer's Research UK Rachel Wood. "An intervention to delay the onset of Alzheimer's by five years could halve the number of people who die with the disease, having a transformative impact on millions of people's lives.
“The G8 is our once-in-a-generation chance to conquer this condition and we must see meaningful action after the talking is over,” Hughes said.