Low levels of air pollution linked to serious changes in the heart – study
Exposure to air pollution has been linked to changes in heart structure similar to the early stages of heart failure, according to a new study.
Researchers examined data from about 4,000 people in the UK and discovered even those exposed to air pollution levels comfortably within UK guidelines exhibited changes in their heart ventricles.
The findings, published in the journal Circulation, showed a clear link between living near loud, busy roads and developing larger right and left ventricles in the heart.
This was even when the areas were not considered dirty air hotspots.
Living near the roads exposed them to nitrogen dioxide and PM2.5, which are small particles of air pollution.
Ventricle reshaping is apparent in the early stages of heart failure, as they are crucial pumping chambers to the heart.
The alarming change was more apparent in those who faced higher nitrogen dioxide levels - with the heart increasing in size for each extra measurement of nitrogen dioxide and PM2.5 to which they were exposed.
Most participants lived outside major UK cities, according to the study, which was a collaboration between scientists at Queen Mary University of London and Oxford University.
It is hoped the research will throw into stark relief the impact air pollution has on the heart - and the link between dirty air and mortality rates.
The study honed in on data from participants in a wider UK biobank study, which included lifestyle information, where they lived and MRI information showing the size weight and function of their hearts at specific times.
Dr Nay Aung, who led the data analysis from Queen Mary University of London, said: "Although our study was observational and hasn't yet shown a causal link, we saw significant changes in the heart, even at relatively low levels of air pollution exposure.
"Air pollution should be seen as a modifiable risk factor. Doctors and the general public all need to be aware of their exposure when they think about their heart health, just like they think about their blood pressure, their cholesterol and their weight."
Further studies in large inner-city areas such as London and Manchester will now be carried out, with experts suspecting they will find "even more pronounced" results.
Professor Jeremy Pearson, associate medical director at the British Heart Foundation, which part-funded the study, said: "We can't expect people to move home to avoid air pollution - Governments and public bodies must be acting right now to make all areas safe and protect the population from these harms.
"What is particularly worrying is that the levels of air pollution, particularly PM2.5, at which this study saw people with heart remodelling are not even deemed particularly high by the UK Government - this is why we are calling for the WHO guidelines to be adopted.
"They are less than half of UK legal limits and while we know there are no safe limits for some forms of air pollution, we believe this is a crucial step in protecting the nation's heart health."