by Exposure to certain forms of air pollution is associated with an increased risk of dementia after the most comprehensive examination of this kind.
It is estimated that the disease affects around 57 million people worldwide, although the number is expected to increase to at least 150 million cases by 2050.
The report created by researchers of the Epidemiology Department of the Medical Research Council at the University of Cambridge included a systematic review of 51 studies.
It was based on data from more than 29 million participants who were exposed to air pollutants for at least one year.
Although air pollution has already been identified as a risk factor for dementia, the most comprehensive study of this kind so far was found that there is a positive and statistically significant connection between three types of air pollutants and dementia.
The pollutants were: PM2.5, which comes from vehicle emissions, power plants and wooden furnaces and fireplaces; Nitrogen dioxide that arises from the combustion of fossil fuels; And soot, which comes from sources such as vehicle emissions and burning wood.
In inhaling, these pollutants can penetrate deeply into the lungs and are associated with different respiratory diseases and an increased risk of certain heart problems.
In particular, the study showed that the relative risk of dementia for a person for 10 micrograms per cubic meter of PM2.5 would increase by 17%. Using equivalent figures for soot, the risk increased by 13%.
Soot and PM2.5 levels approached these levels in 2023 at the locations on the roadside in Central -London, Birmingham and Glasgow.
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The most common cause of dementia is Alzheimer’s disease and around 982,000 people have the disease in Great Britain. Symptoms include memory loss, difficulties with concentration and mood changes.
Dr. Haneen Khreis, the leading author of the study, said that she provided “further evidence of the observation that long -term exposure to air pollution outdoors is a risk factor for the beginning of dementia in previously healthy adults.”
She added: “Combating air pollution can offer long-term health, social, climate and economic advantages. It can reduce the immense stress for patients, families and nurses and at the same time facilitate pressure on roofed health systems.”
Air pollution can lead to dementia by causing inflammation in the brain and oxidative stress, which is a chemical process within the body that can cause damage to cells, proteins and DNA.
The researchers admitted that the report was limited because most of the studies analyzed participants who lived white and in countries with high incomes. They said future studies on air pollution should include more participants with marginalized backgrounds.
Dr. Isolde Radford, Senior Policy Manager at Alzheimer Research UK, said: “This strict review increases the increasing evidence that exposure to air pollution – from traffic vapors to wood burners – increases the risk of dementia.
“Air pollution is one of the most important modifiable risk factors for dementia – but it is not something that individuals can solve alone. There, the government of the government is of crucial importance.
“While the 10-year health plan recognizes the health of air pollution, much more has to be done to tackle this invisible threat.
“Alzheimer’s Research UK calls for a brave, cross-border approach for the health prevention-one, which brings departments beyond health, including DEFRA, to take coordinated measures against the drivers of dementia risk.”
The report was published in Lancet Planetary Health.
