Neighborhood disadvantage linked to higher dementia risk

People living in more disadvantaged neighborhoods may be more likely to develop dementia than people living in neighborhoods with fewer disadvantages, according to a study published on March 26, 2025, online in Neurology^®, the medical journal of the American Academy of Neurology. The study does not prove that neighborhood factors cause dementia; it only shows an association.

Neighborhood status was determined by factors such as income, employment, education and disability.

Our findings show that the community in which you live influences your risk of developing dementia. Most studies of risk factors for Alzheimer's disease focus on the individual level, not the community level. Of course, intervening at the community level is challenging, but prioritizing disadvantaged communities may be an effective way to mobilize resources for older adults and provide avenues for reducing the risk of dementia for the overall community."

Pankaja Desai, PhD, study author of Rush University in Chicago, Illinois

The study involved 6,781 people with an average age of 72 living in four communities in Chicago. Tests of thinking and memory skills were given at the beginning of the study and every three years for at least six years of follow-up. A group of 2,534 people were evaluated for dementia. A total of 66% of the study group were Black participants and the rest were white participants.

Researchers looked at U.S. Census tracts of the four neighborhoods based on amount of disadvantage. A U.S. Census tract is a small area within a county.

By the end of the study, 11% of the people in the tracts with the least disadvantage had developed Alzheimer's disease, compared to 14% in the tracts with the next lowest disadvantage, 17% in the tracts with next-to-highest amount of disadvantage and 22% in the tracts with the highest amount of disadvantage.

Once researchers adjusted for other factors that could affect the risk of dementia, such as age, sex and education, they found that people in the tracts with the most disadvantage were more than twice as likely to develop dementia as those in the tracts with the least disadvantage.

"More Black participants lived in areas with greater disadvantage and more white participants lived in areas with lesser disadvantage. Once we took neighborhood disadvantage factors into account, there was no longer a significant difference between Black and white people in their risk of developing Alzheimer's," Desai said.

The study also looked at the annual rate of decline in scores on tests of thinking and memory skills. The scores of people in the tracts with the most disadvantage declined about 25% faster than those of people in the tracts with the least disadvantage.

A limitation of the study was that participants all lived in Chicago neighborhoods, so the results may not apply to other populations.

The study was funded by the National Institute on Aging.