Researchers at Rush University in Chicago, led by Professor Pankaj Desai, found that your neighborhood strongly influences your risk of developing dementia.
Residents of disadvantaged neighborhoods were about twice as likely to develop dementia as people in more affluent areas.
What Did the Scientists Learn?
The team conducted a six-year study involving approximately 6,800 individuals aged 65 and older (average age 72). Participants lived in four Chicago neighborhoods and underwent regular tests of memory and cognitive ability.
The researchers also collected data on Alzheimer’s disease diagnoses — the most common form of dementia — for roughly 2,500 participants.
By the end of the study, dementia had developed in 22 percent of residents from the most disadvantaged neighborhoods, compared with 11 percent of those from more affluent areas.
This pattern held after the researchers adjusted for age, gender, and education. The risk of developing Alzheimer’s disease remained more than twice as high for residents of the most disadvantaged neighborhoods.
To assess dementia risk at the neighborhood level, the researchers used the Social Vulnerability Index (SVI), a tool that combines 16 variables, including unemployment, income, ethnicity, housing type, and access to transportation.
“Most studies on Alzheimer’s disease risk factors have focused on the individual level rather than the community level. Our findings showed that the community you live in affects your risk of developing dementia,” Professor Desai said.
The team found another striking result: individuals living in the most disadvantaged neighborhoods experienced a significantly faster cognitive decline with age, regardless of whether they had been diagnosed with Alzheimer’s disease. Residents of these areas saw their memory and thinking skills decline at an average rate 25 percent faster than residents of more affluent neighborhoods.
The researchers say these findings are important for planning medical services. “Social characteristics at the neighborhood level are important to consider when planning resources and services to reduce the risk of Alzheimer’s disease,” Desai said in an interview with BBC Science Focus.
The takeaway: brain health depends not only on what happens inside our bodies but also on the environments around us.
The results of the study were published in the journal Neurology.
