As many as 1.9 million people dying every year from heart disease due to outdoor air pollution: World Heart Federation

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The impact of air pollution on heart disease will lead to millions of preventable deaths every year unless governments introduce legislation to tackle the issue, a new global report warns.

Research by the World Heart Federation shows that the number of deaths from cardiovascular conditions caused by air pollution has been on the rise over the past decade and is set to increase further.

A wide range of health problems, including obesity and diabetes, are being exacerbated by the global policy failure to meet air pollution targets, it says, describing it as "the greatest single environmental health risk".

The study found that air quality levels have barely improved despite a range of measures recommended by the WHO and other agencies, leading to as many as 1.9 million dying every year from heart disease and just under a million from strokes due to outdoor air pollution alone.

Air pollution comes from many sources, including transport, industry and wildfires, but the report also details how indoor air pollution poses a serious health risk.

Launched at this year's World Heart Summit, the report reveals the extent of the health crisis caused by outdoor and indoor pollution:

1. The number of deaths from heart disease attributable to air pollution has increased in some regions by as much as 27 per cent over the past decade.

2. Air pollution is nearly ten times the recommended level in countries in Southeast Asia and the Eastern Mediterranean.

3. There are health inequalities between different countries from air pollution in terms of the level of exposure and effect.

4. Tiny invisible particles in air pollution are affecting heart rhythm, blood clotting, the build-up of plaques in arteries, and blood pressure, as well as adversely affecting respiratory diseases and other conditions across the body.

5. Energy efficiency measures in modern homes as part of net-zero can make buildings more air-tight and could increase the build-up of air pollutants in homes, schools, and workplaces.

Data from the report shows that more than half of the nearly 7 million deaths due to air pollution are from cardiovascular conditions (CVDs), a number that's been on the rise over the past decade.

Experts say the number is likely to be significantly higher as this data is from only a single air pollutant and considers only heart disease and stroke, where as many other cardiovascular diseases are known to be worsened by air pollution. Already, cardiovascular disease is the world's top killer, claiming more than 20 million lives each year.

The Western Pacific region saw the highest number of deaths from heart disease and stroke due to outdoor air pollution with nearly 1 million deaths in 2019, and the Southeast Asian Region was a close second, with 762,000 deaths. In the Western Pacific region, 45 per cent of the countries have experienced rising air pollution and suffer the highest mortality from stroke and heart disease induced or exacerbated by it.

In Southeast Asia, Africa and the Eastern Mediterranean, air pollution concentrations are nearly ten times higher than recommended. Countries facing the some of greatest challenges with air pollution include those in the Eastern Mediterranean, with Kuwait, Egypt, and Afghanistan having the highest levels of PM2.5 (fine particulate matter in the air). In Africa, the highest levels of PM2.5 were in Nigeria, Niger, and Cameroon.

The report 'Clearing the Air to Address Pollution's Cardiovascular Health Crisis' shows the sources of pollution and their effects on the heart and circulation. Beyond the smoke and smog that we can see, tiny invisible particles can get deep into the lungs, heart, and other organs.

Even short-term exposure to air pollution can have many effects throughout the cardiovascular system, and long-term exposure worsens chronic diseases such as heart disease, stroke, respiratory disease and diabetes. Adverse effects are even seen on mental health, dementia and in pregnancy.

"Air pollution is ubiquitous, sparing no one. Both outdoor and indoor pollution are driving deaths from cardiovascular disease which still claims the most lives every year. The impacts of air pollution from several sources add up, often widening gaps in healthcare for those also vulnerable to pollution, and worsening outcomes regardless of demographic," said Dr Mark Miller of the University of Edinburgh, and the WHF's Chair of the Air Pollution and Climate Change Expert Group.

Particles that damage air quality vary in composition and size, with PM2.5 being the air pollutant most closely linked to detrimental health effects. The World Health Organisation recommends countries to not exceed 5 micrograms of PM2.5 per cubic metre - expressed as 5 µg/m³. Most are way beyond that threshold, and only 64 per cent have any form of established legislation that include outdoor air quality standards.

While the elderly, children, and those with a lung or heart condition are among those most susceptible to air pollution, short- and long-term exposure affects everyone to varying degrees. Overall, lower-income countries have higher levels of stroke and ischemic heart disease mortality from both outdoor and household air pollution than higher income countries.

The report shows links between type of disease risk and particular sources of pollution including all major cardiovascular conditions such as heart disease, heart failure, high blood pressure, stroke and many more. The increasing threat of other pollutants is concerning since global air pollution-related healthcare costs are already projected to surge from USD 21 billion in 2015 to USD 176 billion in 2060, with annual lost working days potentially increasing to 3.7 billion by 2060.ii

Emphasising today's visible impacts of air pollution, the new report urges action and targeted investment by governments, health and environment decision-makers, and urban planners. It highlights some countries' efforts to reduce or mitigate air pollution with strong potential for yielding health and economic benefits, crucial steps given that the urban population is expected to reach nearly 6 billion in the next two decades.

"We must combat air pollution's stranglehold that is causing so many unnecessary deaths and ill health. We need to accelerate the implementation of air quality guidelines and minimise the use of fossil fuels. Improving transport standards, the provision of clean domestic fuels, smart infrastructure, urban design and agricultural policies can all help air quality. The current air pollution crisis in many parts of the world reflects known pollutants and could worsen with the emergence of others, all of which underscores the importance of preventive action now," said Dr Miller.