New research has pulled forward the date by which dementia cases are projected to double to 2050, a decade earlier than previously predicted.
Experts warn the crisis is moving at an alarming rate, with some groups more exposed than others.
Published in JAMA Neurology on Monday, the study is the most comprehensive estimate of new dementia cases worldwide, drawing on multiple studies spanning almost 40,000 people across 18 countries, the New York Post reports.
Researchers from the University of New South Wales (UNSW) Sydney’s Centre for Healthy Brain Ageing analysed data from 22 studies and found 11.4 million new cases in 2023. The figure is projected to more than double to 24.7 million by 2050.
Liron Sinvani, a geriatrician and director of research and innovation at the Northwell Institute for Healthy Aging, said the equivalent of Australia’s population will develop dementia every year.
“In terms of the scale, obviously, this number of new dementia cases is staggering,” she told the American newspaper. “This is not a future problem. It’s an accelerating epidemic crisis that demands immediate attention.”
The study focused on incidence, the rate at which people develop dementia each year, rather than prevalence, the total number of people living with the condition at a given time.
Ageing populations are driving the rise, Sinvani said. About one in nine people have dementia after 65, “but after 85, it could be almost 1 in 3”.
Two groups, however, recorded higher cases of progressive erosion of memory, concentration and judgment: women and people in low- and middle-income countries.
“Even when controlling for age, the study showed that incidence, not just prevalence, was significantly higher in women, more than men,” Sinvani said.
Incidence among women stood at 10.6 cases per 1,000 people compared with 8.6 among men, which the expert suggested could stem from biological, social, or environmental factors.
New cases were 64 percent higher in low- and middle-income countries compared with high-income nations, putting the greatest burden on regions with the fewest healthcare resources.
Lower levels of education were also strongly linked to higher dementia incidence, matching 2024 research that identified education alongside 13 other modifiable risk factors accounting for nearly half of all cases.
Lead author Ashleigh Vella stressed that understanding these disparities is critical for developing targeted prevention, diagnosis, and care strategies.
Experts noted that prevention remains possible, citing declines in high-income nations achieved through managing cardiovascular health, diabetes, and physical activity.
Sinvani recommended prioritising women for screening, expanding healthcare infrastructure, and promoting lifestyle changes including blood pressure management, social engagement, and reductions in smoking and air pollution.