It will come as no surprise that air pollution is bad for your body and particularly your lungs, but new research suggests that even everyday exposure to air pollutants might have a negative impact on your heart health.
For a long time now we’ve known about the detrimental effects of air pollution on our lung health. While air pollution is not the leading cause of serious diseases like lung cancer (smoking takes that crown), it is among the known risk factors for developing serious cardiovascular health issues. Still, scientists have always suspected that there could be a link between everyday air pollution and heart health problems, but they’ve not had the body of evidence to prove it. New research published this month adds to that suspicion.
Researchers from the London School of Hygiene & Tropical Medicine, publishing in the scientific journal Heart, reveal that they’ve found that even short-term air pollution exposure can be linked with developing an abnormal heart rhythm as well as blood clots in our lungs.
The researchers analyzed health data from three separate collections carried out in England and Wales between 2003 and 2009. The data collections included one set that tracked heart attack/stroke hospital admissions (MINAP), one that tracked what people were admitted for in emergency situations (HES), and the official figures of recorded deaths (ONS).
The researchers also investigated the levels of carbon monoxide, nitrogen dioxide, what’s known as particulate matter, sulfur dioxide and ozone that were recorded over a five-day period throughout the timeframe. They also factored in daily temperatures as recorded by the UK Meteorological Office.
By analyzing all these data samples, the researchers found some patterns started to emerged. After crunching all these numbers it became clear that average levels of pollution cannot be linked with cardiovascular deaths — and that’s good news. It means that our bodies likely can cope with ambient pollution on a normal day.
There were a couple of exceptions though, and the first was the presence of Particulate Matter 2.5 (PM 2.5), which are fine particles that, for example, are found in smoke and haze. When PM 2.5 was found in the atmosphere, so when it was a particularly hazy day but with no other rises in pollution, the numbers suggested an increased risk of irregular heart rhythms, irregular heartbeats and, also, blood clots in the lungs.
One other exception was nitrogen dioxide. The EPA has long warned that short-term exposure to high levels of NO2, say by working next to roadsides or in close confines with running cars, is a risk factor for cardiovascular problems. The research hasn’t linked short-term exposure through ambient pollution before, but the new research does. The London-based scientists found that the presence of nitrogen oxide in our air could be linked with heart failure and an increased risk of some types of heart attack (non-ST elevation).
There was an important note on this finding, however, and that is that when they factored in the age of the people admitted to the hospital for these heart attacks, they all tended to be over a certain age. Specifically, it seemed that the heart health risk affected the over 75s, and usually women. For people below that age limit, the effect wasn’t significant.
As a result, the researchers aren’t prepared to say there is any clear evidence that short term exposure to ambient air pollution significantly boosts the risk of general heart attack and stroke events. They do believe, however, that the research is strong enough to link particulate matter to a greater risk of an abnormal heart rhythm as well as lung blood clots.
Particulate matter is frequently mentioned as a culprit for pulmonary and cardiovascular disease, so this research is supported by a substantial body of other work. The researchers also note that recent efforts to curb pollution and therefore reduce pollution risk may have brought down the average levels of ambient pollution and so lowered our risk. Health experts contend that this is reason enough to keep pushing for further reductions in air pollution.
Researcher Dr Ai Milojevic told BBC News that “Our study found some evidence of air pollution effects on irregular heart beat (arrhythmia) but no clear evidence on heart attack (Myocardial Infarction) and stroke which represents ultimately blood clotting process[es].” She added, “Elderly people and hospital patients with chronic ischaemic heart disease or irregular heart beat are observed to be at particular risk.”
The researchers say that further investigations are needed to explore exactly why particulate matter is routinely tied to cardiovascular and pulmonary health problems.
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