Unless countries address risk factors, the number of people living with dementia could triple t0 153 million in 2050, according to a new study published in The Lancet Public Health.
This increase is primarily due to population growth and an ageing population, but the authors also considered risk factors such as smoking, obesity, high blood sugar, low education and air pollution.
For example, improvements in global education access are projected to reduce dementia prevalence by 6·2 million cases worldwide by 2050. But this will be countered by anticipated trends in obesity, high blood sugar, and smoking, which are expected to result in an additional 6·8 million dementia cases.
Dementia is currently the seventh leading cause of death worldwide and is one of the major causes of disability and dependency among older people globally.
However, dementia is not an inevitable consequence of ageing, a Lancet Commission published in 2020 suggested that up to 40% of dementia cases could be prevented or delayed if exposure to risk factors were eliminated.
The authors highlight the urgent need to roll out locally tailored interventions that reduce risk factor exposure, alongside research to discover effective disease-modifying treatments and new modifiable risk factors to reduce the future burden of disease.
Lead author Emma Nichols from the Institute for Health Metrics and Evaluation (IHME) said: ‘Our study offers improved forecasts for dementia on a global scale as well as the country-level, giving policymakers and public health experts new insights to understand the drivers of these increases, based on the best available data.
‘These estimates can be used by national governments to make sure resources and support are available for individuals, caregivers, and health systems globally.
‘At the same time, we need to focus more on prevention and control of risk factors before they result in dementia. Even modest advances in preventing dementia or delaying its progression would pay remarkable dividends.
‘To have the greatest impact, we need to reduce exposure to the leading risk factors in each country. For most, this means scaling up locally appropriate, low-cost programmes that support healthier diets, more exercise, quitting smoking, and better access to education. And it also means continuing to invest in research to identify effective treatments to stop, slow, or prevent dementia.’