Is Outdoor Air Pollution Triggering Dementia-Like Symptoms?

After analyzing data from adults aged 18 years and older, researchers concluded that "exposure to outdoor air pollution is a risk factor for the onset of dementia."

It is a well-known fact that air pollution poses significant risks to our health, especially when it comes to respiratory issues. But a new study reveals that the dangers extend far beyond what we typically imagine.

According to recent findings, air pollution not only causes common issues that are well-known to common people, such as worsening of asthma, fatigue, headaches, and eye irritation. But, researchers believe that "exposure to outdoor air pollution is a risk factor for the onset of dementia."

The study, which is now published in The Lancet Planetary Health, titled "Long-term air pollution exposure and incident dementia: a systematic review and meta-analysis", reveals long exposure to outdoor air pollution hazards can lead to dementia, including Alzheimer's disease and vascular dementia, where it was once believed that this forgetful disease were largely due to lifestyle and genetics.

Method Of The Study

The Medical Research Council (MRC) Epidemiology Unit at the University of Cambridge, which led the study, conducted a systematic review and meta-analysis of observational studies involving adults above 18 years and older. The participants were analysed on their long-term exposure to outdoor air pollutants for at least one year and a subsequent physician diagnosis of dementia.

How Outdoor Air Pollution Can Lead To Dementia?

As per the publication, the study was conducted after the researchers at MRC generated 15,619 records, of which 51 studies, that include data from 29 million participants, met the inclusion criteria for data extraction.

32 studies, which were included in the final observation, showed a significant association between three types of air pollutants, such as PM2.5, Nitrogen dioxide (NO2) and Soot and the increased risk of dementia.

Senior author Dr Haneen Khreis from the MRC Epidemiology Unit said, "Epidemiological evidence plays a crucial role in allowing us to determine whether or not air pollution increases the risk of dementia and by how much. Our work provides further evidence to support the observation that long-term exposure to outdoor air pollution is a risk factor for the onset of dementia in previously healthy adults.

"Tackling air pollution can deliver long-term health, social, climate, and economic benefits. It can reduce the immense burden on patients, families, and caregivers, while easing pressure on overstretched healthcare systems."

The joint first author, Dr Christiaan Bredell from the University of Cambridge and North West Anglia NHS Foundation Trust, also added, "These findings underscore the importance of additional verification steps beyond gold-standard practices, with the potential to enhance accuracy with a third unaffiliated reviewer as an external check. Future opportunities might exist in leveraging artificial intelligence tools to streamline error-prone tasks, which would serve as an impartial reviewer and potentially reduce the burden of manual oversight."