A new study led by USC looked at more than 214,000 older people from 14 countries. The researchers found that the best ways to stop dementia are not the same everywhere.
Many well‑known risk factors—like low schooling, high blood pressure, and smoking—change a lot from one nation to another. Because of this, a single global plan will not work for everyone.
Diverse Risks Around the World
Most past research came from rich nations such as the United States and Western Europe. To see if those results apply worldwide, the team compared data from both rich and poorer countries.
Big differences appeared. In China, 86 % of seniors had little formal education, while only 12 % of U.S. seniors faced this issue. On the other hand, 45 % of Americans were overweight, compared with just 13 % of people in India.
Even though the exact risks differed, some groups of risks were similar everywhere. Heart‑related problems like high cholesterol and hypertension often showed up together. Lifestyle habits such as smoking and drinking also tended to cluster.
How the Study Was Done
The researchers used data collected between 2009 and 2023 from the "Gateway to Global Aging Data" project. This included long‑term studies from the United States, several European regions, Korea, Mexico, China, Malaysia, Brazil, and India.
They examined 12 factors that can be changed, such as hearing loss, depression, inactivity, and social isolation. They measured how common each factor was, how it varied by age, gender, and education, and how often several factors appeared in the same person.
Tailoring Prevention Programs
The findings can help governments design health programs that match their own people’s needs. For example, a diabetes‑management program could also target high cholesterol and blood‑pressure problems, hitting several related risks at once.
Researchers also reminded readers that these risks are not set in stone. People can change their habits over a lifetime, even though society also shapes the chances of getting dementia.
What Comes Next?
Future work will look at more factors, like poor sleep, and will add new countries such as Kenya and Egypt as data become available.
This research was funded by the National Institutes of Health (grant R01AG030153).