New grant funds global study of why dementia risk varies

What's the study: A research team led by the University of Michigan School of Public Health will combine and standardize memory and thinking test data from older adults in 20 countries to better understand why dementia risk differs around the world. The harmonized data is needed to better understand why some countries have higher rates than others and will allow the researchers to make fair, apples-to-apples comparisons. 

Researchers will examine how education, heart health, social isolation and depression influence cognitive decline and dementia risk, with the goal of identifying the most effective ways to prevent or delay Alzheimer's disease and related dementias. They also want to understand whether these risk factors have a bigger impact in lower-income countries and whether gender inequality makes women more vulnerable to dementia.

Why it matters: Alzheimer's disease and dementia affect millions of people worldwide and are increasing, but the factors that contribute to the disease don't have the same impact everywhere. By comparing data from diverse populations around the globe, researchers hope to identify prevention strategies that could have the greatest effect in different countries and improve brain health for future generations. And by identifying which risk factors have the greatest influence in different countries, the research could help governments and health systems focus on the prevention strategies that are most likely to delay or reduce dementia.

How much and for how long: The $3.2 million grant comes from the National Institute on Aging at the National Institutes of Health. The project will cover a new five-year renewal period from April 2026 to March 2031, with an initial five-year period completed in early 2026.

Who's involved: Lindsay Kobayashi, associate professor of epidemiology and global public health at the School of Public Health. She is also a faculty associate at the Survey Research Center and the Institute for Social Research and associate director for research strategy at the Center for Global Health Equity.

"This project takes advantage of the Harmonized Cognitive Assessment Protocol, a major National Institutes of Health-funded initiative that provides comparable data on cognitive aging around the world," Kobayashi said. "Because risk factors and social conditions differ so much from one country to another, comparing them can show us which prevention strategies may matter the most, and where."