Air Pollution Linked to Increased Risk of Dementia: Cambridge University Study

A new study by researchers at the University of Cambridge has found a positive and statistically-significant association between long-term exposure to three common air pollutants and dementia. The study, published in The Lancet Planetary Health, was the most comprehensive assessment of its kind, involving a systematic review of 51 studies and drawing on data from over 29 million participants. The findings suggest that exposure to particulate matter 2.5 (PM2.5), nitrogen dioxide (NO2), and soot (black carbon) can increase the risk of dementia by 17%, 3%, and 13% respectively, for every 10 micrograms per cubic meter (μg/m³) of long-term exposure.

Key Takeaways:

• The study found a positive and statistically-significant association between long-term exposure to three common air pollutants (PM2.5, NO2, and soot) and dementia.
• For every 10 micrograms per cubic meter (μg/m³) of long-term exposure to PM2.5, an individual's relative risk of dementia would increase by 17% from the baseline.
• For every 10 μg/m³ of long-term exposure to nitrogen dioxide (NO2), the relative risk of dementia increased by 3%.
• Soot exposure was found to increase dementia risk by 13% for each 1 μg/m³ of long-term soot exposure.
• The study involved a systematic review of 51 studies and drew on data from over 29 million participants.
• The research highlights the importance of an interdisciplinary approach to dementia prevention, including urban planning, transport policy, and environmental regulation.
• The study's findings underscore the need for policy makers and healthcare professionals to take action to reduce air pollution and prevent dementia.
• Dr. Christiaan Bredell from the University of Cambridge, and the study's first author, emphasizes that preventing dementia is not just the responsibility of healthcare, but also involves urban planning, transport policy, and environmental regulation.

Statistics:

• 99% of the global population breathes air that exceeds WHO guideline limits and contains high levels of pollutants (WHO data).
• 57 million people had dementia worldwide in 2021, with the number expected to increase to at least 150 million cases by 2050 (WHO data).
• The average PM2.5 levels at Delhi's ITO pollution AQI monitoring station over the last 24 hours (as of Saturday, 4 pm) was 77 μg/m³.
• The average NO2 levels at the ITO station over the last 24 hours (as of Saturday, 4 pm) was 83 μg/m³.

Sources:

• The Lancet Planetary Health (July 24)
• World Health Organization (WHO)
• University of Cambridge
• Central Pollution Control Board