In 2023, an estimated 11.4 million people developed dementia. By 2050, that figure could reach 24.7 million new cases every year, according to a new global study. The research also points to two groups already carrying a heavier load: women, and people who live in low- and middle-income countries.
The findings, announced in October 2026, appear in JAMA Neurology. They come from the Centre for Healthy Brain Ageing at the University of New South Wales (UNSW) Sydney. As Fast Company reported, the projection assumes the world does not mount large-scale prevention efforts. In other words, it describes where things are headed if nothing changes.
Counting new cases, not just total cases
Most headline dementia numbers describe prevalence, meaning how many people are living with the condition at a given time. The World Health Organization puts that figure at 57 million people as of 2021. Earlier research, cited in a UNSW statement, projected it could approach 150 million by 2050.
This study looks at incidence instead. That is the number of people who newly develop dementia each year. The WHO fact sheet cites nearly 10 million new cases a year, while this study estimates 11.4 million for 2023. The two figures come from different analyses. Governments use it to estimate how much diagnosis, clinical care and support they will need to provide, and to decide where prevention could do the most good.
Incidence data has been harder to come by. Studies that follow people over time are less common than studies that count existing cases, especially in lower-income countries. Differences in how researchers diagnose and calculate dementia have also made country-to-country comparisons shaky.
What the data from 18 countries and territories shows
To get around that, the team used the Cohort Studies of Memory in an International Consortium, known as COSMIC. It pooled 22 population-based studies covering 38,418 people across 18 countries and territories on six continents. Twelve of those places were high-income and six were low- or middle-income. The researchers applied the same statistical methods and clinically based diagnoses throughout.
Over more than 287,000 person-years of follow-up, 3,001 participants developed dementia. A person-year is a way of counting that gives each person credit for every year they were observed. The rates below are per 1,000 person-years, adjusted for age.
- Overall: 9.7 new cases
- Women: 10.6 new cases, compared with 8.6 for men
- Low- and middle-income countries: 13.6 new cases, compared with 8.3 in high-income countries
The income gap is the bigger of the two. Lead author Dr. Ashleigh Vella said this is the first time such a geographically varied set of populations has been compared using one statistical approach.
The question the study can’t answer yet
The researchers did not find out why women and people in lower-income countries show higher rates. They caution that the explanation is likely a mix of health, social, economic, educational and environmental factors, and that more research in diverse populations is needed.
The sample has limits too. Only six of the 18 places were low- or middle-income, compared with 12 high-income ones. Senior author Prof. Perminder Sachdev called for better local data so that services can be planned around what each country actually needs.
That need is pressing because of where the growth is expected. Sachdev said the higher incidence in these regions is especially concerning because they are ageing quickly while often having the fewest resources for prevention, diagnosis and care. The WHO notes that more than 60% of people living with dementia already reside in low- and middle-income countries.
Who pays when cases rise
Dementia affects memory, thinking and the ability to manage daily life. It is more common after 65, though the WHO stresses it is not an inevitable part of ageing. There is no cure, but treatment and support can help.
The cost is already large. The WHO estimates dementia cost the global economy US$1.3 trillion in 2019. About half of that came from care provided by family and friends, who spend an average of five hours a day on care and supervision. Women provide 70% of those care hours, so they are affected twice over, as patients and as caregivers.
Dr. Liron Sinvani of the Northwell Institute for Healthy Aging told U.S. News & World Report the trend is “an accelerating epidemic that demands immediate attention.” She said health systems need to prepare for a surge in demand for diagnosis and care, and that lower-income countries will need better infrastructure.
Why the study’s authors say prevention can’t wait
Prof. Henry Brodaty, a co-author, framed the response as a spectrum. “We cannot simply wait for people to develop dementia and then respond,” he said. His list runs from reducing modifiable risk factors and spotting people at risk earlier, to improving diagnosis, treatment and care.
The WHO lists several factors linked to higher dementia risk, including high blood pressure, diabetes, hearing loss, physical inactivity, smoking and air pollution. It says risk builds across a lifetime, and that poverty, limited education and unequal access to health care also play a part. That means individual habits are only one piece. The WHO says lowering risk also takes supportive systems and policies, and its risk reduction guidelines give countries and health systems recommendations for building them.
The new numbers do not say who will develop dementia. They say where the pressure is likely to land, and that the places least equipped to absorb it may feel it first. Anyone with concerns about their own memory or health should speak with a clinician.
Hello reader, I’m Abhishek Kumar Shankhwar, a mental health and wellness enthusiast and a digital marketer by profession. I’m driven by a purpose to inform, inspire, and positively impact lives through meaningful content. You’ll likely find me exploring human psychology, spirituality, experimenting in the kitchen, or reflecting on life’s deeper questions. I’m also VP of Digital Marketing at Dignitas Digital, an award-winning digital agency in Philadelphia, where we drive client success through AI-powered, ROI-driven marketing strategies and tech-forward solutions. Connect with me on LinkedIn to explore potential synergies.
Disclaimer: This article is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional before making decisions about your health, including changes to your diet, exercise, supplements, or medications.
