increased risk of heart attack

Air pollution is extremely harmful to health, everyone knows that. According to scientists, it increases blood pressure, the risk of atherosclerosis, asthma, brain tumor and weakens the bones and even the fetus when a pregnant woman is too exposed. Today, a new study shows a link between air pollution and increased risk of myocardial infarction, a condition better known as heart attacks. According to a study published in the journal Environmental Health Perspectives, exposure for only a few hours to the ultrafine particles common in air pollution can potentially trigger a non-fatal crisis.

Ultrafine particles pose a health risk due to their small size, large area per unit mass and their ability to penetrate cells and enter the blood system. “We were the first to demonstrate the effects of CPUE on the health of asthmatics in an epidemiological study in the 1990s,” explains Annette Peters, director of the Institute of Epidemiology at the Helmholtz Center in Munich (Germany) and co – author of this article. “Since then, around 200 other studies have been published. However, the epidemiological evidence remains inconsistent and insufficient to infer a cause and effect relationship. ”

According to the study authors, this could be explained in part by the differences in size and exposure parameters examined to characterize ambient exposure to ultrafine particles. Here, the researchers wanted to understand whether transient exposure could trigger heart attacks and whether other measures such as particle length and surface concentrations could improve the study of the health effects of these particles.

The first hours of exposure are the most dangerous

Kai Chen, assistant professor at the Yale School of Public Health (USA) and German colleagues from the Helmholtz Center, the University Hospital of Augsburg and the Hospital of Nördlingen, studied data from a register of all non-fatal infarction cases in Augsburg between 2005 and 2015. Thus, 5,898 patients were involved.

Researchers compared individual heart attacks to ultra fine particulate matter (UFP) data on air pollution at the time of the infarction. After taking into account other factors such as the day of the week or the patient’s socioeconomic status, they found that “the tiny particles of air pollution can play a role in serious heart disease. ”

“This is particularly true in the first hours of exposure,” says Chen, recalling that we “suspected” this phenomenon “for a long time”. “This is an important step towards understanding the appropriate indicator of exposure to ultrafine particles to determine short-term health effects, since the effects of particle length and surface concentrations were stronger than those of particle number concentration and remained similar after adjustment for other air pollutants, ”he says.

Each year in France, 7,500 people die from nitrogen dioxide

And to continue: “Our future analyzes will examine hourly exposures combined with both air pollution and extreme temperatures. We will also identify vulnerable sub-populations with regard to pre-existing illnesses and taking medication. ”

In France, air pollution is a real public health issue. On October 24, European justice published a report accusing France of having passed since 2010 “systematically and persistently” the limit in air of nitrogen dioxide (NO2), a polluting gas mainly from diesel engines. In the event that the air pollution rate is exceeded, European legislation obliges the pinned country to establish an air quality plan, and to ensure that the period of excess is “as short as possible”.

“The government is determined to quickly and sustainably improve air quality, which is an imperative for public health and the environment,” said the Ministry of Ecological Transition to justice. According to the latest report from the European Environment Agency on air quality, nitrogen dioxide causes 7,500 deaths each year in France (68,000 in the European Union).

As for myocardial infarction, which corresponds to the partial destruction of the heart muscle, due to the obstruction of an artery which supplies the heart with blood, and therefore with oxygen, it concerns 80,000 people in France. Among them, 12,000 die, recalls Inserm. Besides air pollution, the best known risk factors are smoking, high cholesterol, hypertension, type 2 diabetes, obesity and stress. Men over 55 are also more likely than others to have heart attacks. However, after menopause, the risks are equal for both sexes.

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