A new global dementia study has revealed the number of people developing the debilitating disease annually will double by 2050, with higher rates among women and in low-income countries.
The international research, led by the University of NSW’s Centre for Healthy Brain Ageing (CHeBA), found 11.4 million people developed dementia globally in 2023, and that figure is projected to rise to 24.7 million a year by 2050.
The study was led by the University of NSW’s Centre for Healthy Brain Ageing. Getty
In 2024, dementia overtook ischaemic heart disease to become Australia’s leading cause of death for the first time, in line with the nation’s ageing population.
Co-author Professor Henry Brodaty, the CHeBA co-director and this year’s Senior Australian of the Year, said the study proved investment in dementia prevention was urgent.
“Twenty-four million new cases of dementia every year would place enormous pressure on individuals, families, health systems and economies around the world,” Brodaty said.
“Population ageing means we cannot simply wait for people to develop dementia and then respond.
“We need to act across the spectrum - from reducing modifiable risk factors and identifying people at risk earlier, through to improving diagnosis, treatment and care.”
The study found the incidence of dementia globally was higher among women than men and higher in low- and middle-income countries, than in high-income countries, although it did not explore why.
“What stands out is that dementia incidence is not evenly distributed,” lead author Dr Ashleigh Vella from CHeBA said.
“We see higher rates among women and in low- and middle-income countries.
“Understanding these differences is critical if we are to develop dementia prevention, diagnosis and care strategies that respond to the populations facing the greatest future risk.”
Dementia overtook heart disease to become Australia’s leading cause of death. Getty
Calculating incidence, the rate at which people develop dementia or the number of new cases per year, rather than prevalence, which measures the total number of people living with the disease at a given time, is more useful for government and health systems to anticipate future demand for care and services while helping best target prevention efforts.
International comparisons of incidence have been challenging, due to differences in diagnostic and statistical approaches and a lack of studies estimating prevalence in low- to middle-income countries.
The higher incidence in low- to middle-income countries is particularly concerning given they often have fewer resources for prevention, diagnosis and care, senior author and CHeBA co-director Professor Perminder Sachdev said.
“Our findings highlight the urgent need to strengthen dementia risk reduction and health-care capacity globally, while investing in better local data so services can be planned according to the needs of individual countries.”