New research finds that older, non-white adults are more likely to live in areas with higher air pollution and near toxic disposal sites, among or environmental injustices, potentially underlying their cognitive health.

“A lot of money has been spent on understanding the genetics and pathological characterization of Alzheimer’s disease,” says P. Murali Doraiswamy, professor of psychiatry and behavioral sciences at Duke University School of Medicine, and senior author of the study published in the Journal of Alzheimer’s Disease Reports.

“But we still don’t have a good way to quantify the dozens of environmental risks for the disease and how they may interact together.”

The results add to a growing area of research exploring the connections between environmental factors and brain health, racial injustices, and aging, and suggests that looking at a patient’s address may be just as important for care providers to consider as listening to their heart or ordering a brain scan.

Location and Brain Health

Where someone lives can influence their brain health. Middle-aged women get a cognitive boost when residing in areas with more trees, flowers, parks, and other green spaces, whereas living in poorer neighborhoods with more polluted air elevates risks for and rates of Alzheimer’s disease.

These are piecemeal examples, though.

“An all-encompassing snapshot tying multiple environmental factors and resources available based on where someone lives to neurodegenerative disorders, like Alzheimer’s disease, has not been explored as well,” says first author Alisa Adhikari, a clinical research associate in the Doraiswamy lab.

The researchers recruited 107 participants aged 55 to 95 with mild cognitive impairment living in or around New York City or Durham, North Carolina to study the effectiveness of computerized cognitive training therapies, such as crossword puzzles and brain games, on slowing dementia progression over 78 weeks.

To get a fuller sense of how place, race, and the mind influence each other, coauthor Adaora Nwosu, a Duke medical student, pulled in data from the Center for Disease Control Environmental Justice Index (EJI).

The EJI provides census-tract specific information about 36 environmental and social burden indicators such as neighborhood walkability and access to green spaces, diesel exhaust, air, water, and noise pollution levels, as well as the likelihood of living in older homes with greater exposure to lead or asbestos.

Non-white participants, mainly Black enrollees, were found to face higher environmental burdens.

“Minorities had greater exposure to ozone, diesel, particulate matter, carcinogenic air toxins, lack of recreation of parks, and proximity to toxic disposal sites,” Adhikari says, which she says explains, in part, the higher environmental burden scores.

Read the full article about Black adults who have Alzheimer's by Dan Vahaba at Futurity.