Cardiovascular diseases are the leading cause of death and disability. It is estimated that in 2019 they were responsible for 32% of all deaths worldwide: 18.6 million deaths. Of these, 85% were due to acute myocardial infarction and stroke. It has been clearly visible the impact that the control of individual cardiovascular risk factors - such as tobacco consumption, hypertension, high cholesterol, diabetes, obesity, among others - has in reducing the incidence of cardiovascular diseases and the mortality associated with. In addition to these better-known cardiovascular risk factors and to the effects of other health problems, there are other issues related to increased cardiovascular risk: Poor socio-economic conditions and professional stress , especially when a high professional demand and disproportionately low remuneration are combined; Environmental problems, such as pollution , in particular air pollution. Pollution and cardiovascular diseases The various forms of pollution were responsible in 2019 for about 9 million deaths worldwide, 61.9% of which are related to cardiovascular diseases, mainly: Acute myocardial infarction and angina pectoris (31.7%); Stroke (27.7%). Air pollution alone was responsible for 6.7 million of those deaths and is therefore the fourth leading cause of illness and death worldwide . Its effects are mainly respiratory, but cardiovascular diseases account for 40%-60% of premature deaths related to this form of pollution. Individual particularities, such as age and living conditions, increase susceptibility and exacerbate the health effects of pollution. Air pollution Air pollution refers both to outdoor and indoor air pollution . With better living conditions, deaths due to i ndoor air pollution have decreased: they were 2.3 million in 2019. However, those due to outdoor air pollution have increased by around 50% since the beginning of the 20th century and were 4.1 million in 2019. The World Health Organization estimates that 91% of the world population still live in places where air pollution levels exceed the limits recommended by this organization. The effects of air pollution on mortality vary widely in different regions of the globe. They are responsible for fewer deaths in more developed countries that have adopted pollution control measures for a longer time, where these measures are more restrictive and technological development is more advanced. At the other extreme, there are countries where cardiovascular deaths due to air pollution are the most important. Polluting compounds in the air There are solid, liquid and gaseous pollutants in the air. Suspended particles are the solid air pollutant and are closely linked to health effects, particularly fine and ultrafine particles. The smaller the particles, the deeper they reach the respiratory organs. It is now known that exposure to airborne pollutant particles, whether short-term or long-term exposure, always has harmful effects: Short-term exposure to fine and ultrafine particles is associated with hypertension, myocardial infarction and stroke (fatal and non-fatal); Long-term exposure to fine particles is associated with an increased risk of atherosclerosis, myocardial infarction, hypertension and other cardiovascular diseases, including arrhythmias and heart failure, among others. In addition to quantity and size, the composition and properties of the particles suspended in the air also vary. It depends, for example, on its origin. In urban areas, fine and ultrafine particles are largely due to combustion in vehicles, industry and energy production, and these are also a source of gaseous pollutants in the air. Climate changes, in turn, exacerbates the effect of air pollutants. Extreme temperatures and their variability are associated with increased mortality from myocardial infarction and stroke. In 2021 the World Health Organization changed the recommended airborne fine particulate limits to 5 µg/m 3 , half of its previous recommendation. These air quality standards have thus become the most demanding in the world. Australians and Americans follow, and then the European ones. Prevent pollution and reduce cardiovascular risk All studies on the health effects of air pollution reveal an increased risk of cardiovascular disease with pollution. Therefore, in the prevention of cardiovascular diseases, the role of pollution as an avoidable risk factor cannot be forgotten . Avoiding exposure to polluted environments, by any form of pollution, can save many lives. Any individual gesture that avoids or counteracts pollution, even small, will play a good role in collective health. Living in a healthier environment is a fundamental reinforcement so that efforts for a healthier lifestyle, which are already a concern of so many of us, are not thwarted. Author : Victor Gil Sources de Bont J, Jaganathan S, Dahlquist M, Persson Å, Stafoggia M, Ljungman P. Ambient air pollution and cardiovascular diseases: An umbrella review of systematic reviews and meta-analyses. J Intern Med 2022;291:779-800. doi: 10.1111/joim.13467. Rajagopalan S, Landrigan PJ. Pollution and the heart. N Engl J Med 2021;385:1881-92. doi: 10.1056/NEJMra2030281. Meet the cardiology clinical team from Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
