Dementia risk factors vary widely across countries, highlighting the need for tailored prevention strategies.
A large international study has found that the risk factors for dementia vary widely from one country to another, suggesting that a single global approach to dementia prevention may not be effective.
Researchers say prevention strategies should be tailored to the unique health, lifestyle, and social conditions of individual populations while continuing to address common risk factors shared across countries (1✔ ✔Trusted Source
Differences in the prevalence and patterns of dementia risk factors: a harmonized cross-national comparison of 14 geographies using data from the Gateway to Global Aging
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The findings come from a USC-led study involving more than 214,000 older adults across 14 countries and regions. The research, presented at the Alzheimer’s Association International Conference 2026 and published in The Lancet Healthy Longevity, is one of the most comprehensive analyses to date of modifiable dementia risk factors across diverse populations.
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Dementia Risk Factors Differ Across Countries
Dementia is one of the fastest-growing public health challenges worldwide, affecting millions of people and placing a significant burden on families and healthcare systems. While previous research has identified several lifestyle and health factors that increase dementia risk, most of that evidence comes from high-income countries such as the United States and Western Europe.
To determine whether these findings apply globally, researchers analyzed harmonized health data collected between 2009 and 2023 from long-term aging studies conducted in the United States, England, Ireland, Northern Ireland, several European regions, Korea, Mexico, China, Malaysia, Brazil, and India.
The results revealed major differences in the prevalence of controllable dementia risk factors between countries.
For example, low educational attainment was identified as a risk factor in 85.6% of older adults in China, compared with only 12% in the United States. In contrast, high body mass index (BMI), a measure of excess body weight, affected 44.9% of older adults in the United States, while only 13.3% of participants in India had the same risk factor.
These findings suggest that health priorities differ significantly between populations and that prevention programs need to reflect those regional differences rather than relying on a universal strategy.
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Some Dementia Risk Factors Were Shared Worldwide
Although the prevalence of individual risk factors varied, researchers also discovered several surprising similarities.
Cardiovascular risk factors—including high blood pressure and high cholesterol—frequently occurred together across different countries. Similarly, lifestyle-related behaviors such as smoking and excessive alcohol consumption tended to cluster in comparable patterns regardless of geography.
Lead author Emma Nichols, a research scientist at the USC Schaeffer Institute for Public Policy & Government Service, said these shared patterns were one of the study’s most unexpected findings.
The researchers believe these common clusters provide an opportunity to design prevention programs that target multiple related health conditions simultaneously. For example, a healthcare program designed to improve diabetes management could also include screening and treatment for high blood pressure and cholesterol, reducing several dementia risk factors at the same time.
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Researchers Examined 12 Modifiable Risk Factors
The study focused on 12 modifiable dementia risk factors identified by the Lancet Commission, including hearing loss, depression, physical inactivity, social isolation, smoking, obesity, hypertension, diabetes, and other lifestyle and health conditions that can potentially be improved.
Researchers compared how common each risk factor was, how risk varied according to age, gender, and education level, and how often several risk factors occurred together in the same individual.
The findings showed that dementia risk is shaped not only by personal health but also by social, educational, and environmental factors that differ between countries.
Dementia Prevention Starts Long Before Old Age
Researchers emphasize that dementia risk is not fixed. Many of the identified risk factors develop gradually over a person’s lifetime and can be modified through healthier lifestyle choices and improved access to healthcare.
Managing blood pressure, maintaining healthy cholesterol and blood sugar levels, staying physically active, avoiding smoking, limiting alcohol consumption, addressing hearing loss, and staying socially engaged are among the measures that may help lower dementia risk.
The study also highlights the importance of improving education and reducing health inequalities, particularly in countries where these factors contribute substantially to dementia risk.
Future Research May Include New Risk Factors
The researchers say the work is far from complete. As additional international data become available, future studies will expand to include more countries and examine emerging dementia risk factors such as poor sleep, which is increasingly being linked to cognitive decline.
New data collection has already begun in countries including Kenya and Egypt, allowing researchers to better understand dementia risks in populations that have historically been underrepresented in global studies.
The study suggests that preventing dementia requires both global and local solutions. While certain health risks, such as cardiovascular disease and unhealthy lifestyle habits, appear to be common across many populations, other risk factors vary considerably from country to country.
Researchers say tailoring prevention strategies to regional health challenges while continuing to address shared risk factors could improve efforts to reduce dementia cases worldwide. They also stress that dementia is not an inevitable part of aging, and taking steps to manage modifiable risk factors throughout life may help protect brain health in later years.
Reference:
- Differences in the prevalence and patterns of dementia risk factors: a harmonized cross-national comparison of 14 geographies using data from the Gateway to Global Aging – (https://www.thelancet.com/journals/lanhl/article/PIIS2666-7568(26)00051-6/fulltext)
Source-Medindia