A study conducted jointly by Duke and Columbia Universities has brought to light urgent environmental injustices affecting older, non-white adults. These individuals are disproportionately located in areas with higher air pollution and close proximity to toxic disposal sites. P. Murali Doraiswamy, MBBS, FRCP, a professor at Duke University’s School of Medicine and senior author of the study, emphasised the pressing need to quantify the combined environmental risks contributing to Alzheimer’s disease, despite the substantial investment in understanding its genetics and pathology.
Published in the Journal of Alzheimer’s Disease Reports on May 14, 2024, the study underscores the critical role of residential addresses in healthcare, akin to assessing cardiovascular health or ordering diagnostic imaging. It reveals that middle-aged women residing in green spaces experience cognitive benefits, whereas those in economically disadvantaged neighbourhoods with higher air pollution face increased Alzheimer’s disease risks.
The study focused on 107 participants aged 55–95 with mild cognitive impairment from New York City, NY, and Durham, NC, evaluating the efficacy of cognitive training therapies over 78 weeks. Alisa Adhikari, the study’s lead author, highlighted the need for comprehensive research capturing various environmental factors and available resources related to neurodegenerative disorders like Alzheimer’s disease.
Co-author Adaora Nwosu integrated data from the Environmental Justice Index (EJI) of the Center for Disease Control, revealing that non-white participants, mainly Black enrollees, face higher environmental burdens such as ozone exposure, diesel exhaust, and limited access to recreational parks. They also experience greater social vulnerability, likely influenced by historical injustices.
While the study did not establish direct correlations between race, location, and cognitive decline, analysis of EJI data revealed significant differences in pollution levels between study sites, suggesting geographical disparities impacting cognitive health outcomes. Dr. Doraiswamy emphasised the study’s insights in prompting a reconsideration of the homogeneity assumption regarding environmental exposures in clinical trials.
The research team recognises that the solution to these disparities lies in collaboration. They plan a larger national study involving thousands of participants, incorporating objective measures such as MRI scans to track cognitive health longitudinally. Dr Doraiswamy concluded that it is only through collaboration between clinical and environmental researchers that we can effectively mitigate racial disparities and ensure equitable access to environments conducive to brain health.
More information: Alisa Adhikari et al, Characterizing Neighborhood Vulnerabilities in Mild Cognitive Impairment using the Environmental Justice Index, Journal of Alzheimer’s Disease Reports. DOI: 10.3233/ADR-240020
Journal information: Journal of Alzheimer’s Disease Reports Provided by IOS Press
