World Environment Day 2024: Did you know air pollution can cause heart disease?

At the recently concluded World Heart Summit in May, the World Heart Federation published a research study that has indicated 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 if there is no timely intervention by governments. The non-governmental organisation that has been recognised by the World Health Organization as its partner in dealing with cardiovascular disease around the globe, has found that as many as 1.9 million people are dying every year from heart disease and just under a million from strokes due to outdoor air pollution alone. While heart disease is attributed to various lifestyle factors, what connection does air pollution have with heart disease?

Every year, World Environment Day is observed on June 5 by people around the world to raise awareness and protection of the environment. While deforestation is a concerning issue that often comes at the cost of development, the result is the lack of proper steps to combat air pollution, especially in a city like Mumbai. It not only highlights the need to take necessary measures at the personal level but also governance level to curb air pollution and in the process reduce the effects it has on our health and particularly heart health. One of the easiest ways is by planting trees, say experts, but there is a lot more that needs to be done at the policy level. The WHF study found that Southeast Asia lost over 762,000 people to ischemic heart conditions and strokes that can be attributed to air pollution over the past decade. Dr Mark Miller of the University of Edinburgh, chaired the study taken up by the Air Pollution and Climate Change Expert Group at WHF.

With the growing concern about the environment and heart diseases, mid-day.com spoke to Dr Ashish Mishra, consultant interventional cardiologist Wockhardt Hospitals in Mira Road and Dr Bikky Chaurasia, consultant, Internal Medicine, Kokilaben Dhirubhai Ambani Hospital Mumbai to understand more. They not only highlight the role of air pollution with respect to heart disease, but also delve into why people should take it seriously in Mumbai.

What is the connection between air pollution and heart diseases?
Mishra: Air pollution can lower air quality by containing dirt, dust particles, bacteria, microorganisms, and harmful gases. Millions of people inhale these harmful particles and gases. These particles then enter an individual's lungs and cause vascular inflammation and stress (endothelial dysfunction). This inflammation can damage blood vessels and also increase blood pressure by affecting vascular resistance and reflex. The sudden spike in blood pressure levels can strain the heart, increasing the risk of getting heart-related diseases.

Chaurasia: Air pollution, particularly fine particulate matter (PM2.5) and nitrogen dioxide (NO2), can significantly impact heart health. Exposure to these pollutants increases the risk of heart disease by promoting inflammation, oxidative stress, and endothelial dysfunction. PM2.5 particles can penetrate deep into the lungs and bloodstream, affecting blood vessels and contributing to atherosclerosis. Furthermore, NO2 exposure is associated with hypertension and adverse cardiac events.

What are the common causes of heart diseases?
Mishra: There are various factors that could result in cardiovascular diseases and impact overall health. Certain health issues such as high blood pressure, diabetes, thyroid disorder, high cholesterol levels, obesity, depression, anemia, sleep apnea, and stress could increase the risk of getting heart disease. Similarly, certain lifestyle habits such as excessively drinking alcohol, smoking cigarettes, eating food that contains high levels of sugar and salt, eating at unusual hours mostly at night, and having poor sleep routines can also lead to various heart-related diseases which can be life-threatening.

Chaurasia: Besides air pollution, common risk factors for heart disease include smoking, poor diet (high in saturated fats, salt, and added sugars), physical inactivity, obesity, diabetes, and stress. Genetic predisposition and family history also play a role.

Has the role of air pollution always been there and only grown over time or is it a new phenomenon?
Chaurasia: Air pollution has been a concern for decades, but its impact on heart disease has intensified due to urbanisation, industrialisation, and increased vehicular emissions. As cities grow, exposure to pollutants rises, contributing to the observed increase in heart disease deaths.

Which are the common diseases caused due to air pollution?
Mishra: Air pollution decreases the quality of air which can adversely impact an individual's respiratory system leading to various health issues such as asthma, COPD (chronic obstructive pulmonary diseases), bronchitis, pneumonia, interstitial lung disease and reduced lung functions.

Besides the respiratory system, it can also impact an individual's overall health such as a weakened immune system, eye infection, skin-related problems like eczema and psoriasis, cardiovascular diseases, liver diseases and kidney diseases.

Chaurasia: Apart from heart disease, air pollution is linked to respiratory conditions (e.g., asthma, chronic obstructive pulmonary disease), stroke, and even cognitive decline. The cardiovascular system is particularly vulnerable.

Even though Mumbai's air quality ranges between poor, moderate, and good, do these three levels harm people differently?
Mishra: Yes, different air quality levels in Mumbai can harm an individual's health and overall well-being differently. Good air quality is an ideal level where the air is naturally fresh and poses no harm to individuals and also the environment.

However, it can not be denied that Mumbai has severely faced air pollution issues and its air level mostly resides between moderate to poor on most of the days. Long-term exposure to harmful toxins and chemicals in the air are linked to health problems like skin problems, cardiac issues, eye allergies and infections, stroke, chronic obstructive pulmonary disease (COPD), lung cancer, triggered asthma incidences, lower respiratory infections, premature death, metabolic disorders such as diabetes, cognitive decline and reduced fertility.

Chaurasia: Poor air quality affects everyone, but vulnerable populations (children, elderly, and those with pre-existing conditions) suffer more. Even moderate pollution levels can harm health, exacerbating existing heart conditions.

Which areas in Mumbai should people be concerned about when it comes to air pollution?
Mishra: According to the Mumbai Air Quality Index AQI, areas such as Bandra, Bandra Kurla Complex, Colaba, Deonar, Sion, and Vasai West, currently have poor air quality as per reports. Residents should take necessary precautions to safeguard themselves from air pollution.

Avoid stepping out of the house during peak traveling hours when most people commute to their offices by vehicles like bikes, cars, rickshaws, or trains and the air pollution is at its peak.

Chaurasia: High-traffic zones, industrial areas, and regions near construction sites are critical. Coastal areas may experience additional pollution due to shipping and port activities.

Why should people be worried about heart diseases? Are more people coming to do health checkups for it?
Mishra: Heart disease is the leading cause of death globally. The quality of lifestyle has significantly decreased over the years due to busy work life, poor diet, eating at unusual hours, lack of mobility and exercises, increasing stress, and habits like excessive smoking and drinking alcohol, increasing the risk of developing serious health complications. After Covid, people have now started prioritising health over work and should be encouraged to regularly seek health checkups for healthier lifestyles.

Chaurasia: Rising heart disease rates emphasise the need for preventive measures. Regular health checkups are crucial to detect risk factors early and manage them effectively.

Planting more trees has always been a solution to reduce air pollution but do you think Mumbai has enough tree cover to curb it?
Mishra: Mumbai doesn't have enough tree cover to effectively curb air pollution as per reports. It is high time to plant more and more trees to safeguard Mumbaikars from increasing air pollution and heart diseases caused by air pollution. Mumbai is highly populated, which has led to its urbanisation, where numerous trees are chopped off to build these lavish buildings by breaking the natural balance in the environment.

Chaurasia: While planting trees helps, Mumbai's tree cover is insufficient to fully combat pollution. Urban planning should prioritise green spaces and sustainable transportation.

How can people deal with air pollution on a personal level? Share tips
Mishra: People can personally deal with air pollution by avoiding the use of a car or bike for small distances, instead choose walking or public transportation like Mumbai local trains or metro to minimise air pollution on an individual level.

Another major factor that stirs up air pollution is cigarette smoke. Smoking is not only harmful to an individual's health but also nature and air quality as it releases numerous cancer-causing chemicals, and toxins into the air. Hence, individuals should opt for a smoke-free life, which will also help curb air pollution and passive smoking.

Chaurasia: At the personal level, people can follow these steps:

Use masks: Wear masks when outdoors to reduce exposure.

Indoor air quality: Improve ventilation and use air purifiers.

Physical activity: Exercise indoors during peak pollution hours.

Diet: Consume antioxidant-rich foods to counter oxidative stress.

Avoid smoking: Quit smoking and avoid secondhand smoke exposure.

How can the authorities deal with air pollution in Mumbai with policies?
Mishra: Authorities or Brihanmumbai Municipal Corporation could come up with several strategies and initiatives to curb air pollution in Mumbai such as strict guidelines for factories, construction work and industries to treat the harmful smoke and chemicals before releasing them into the air or environment.

Dumping grounds have been one of the leading problems in Mumbai, where tonnes of industrial, household, and hazardous waste is dumped and burned on a daily basis which not only causes air pollution but also increases the risk of getting affected with several health issues and water borne diseases.

With global warming and air pollution a huge concern today, why should people be worried about the connection between heart diseases and air pollution?
Mishra: Air pollution significantly increases the risk of heart-related diseases. Certain harmful toxins, particles such as fine particulate matter, nitrogen dioxide, and sulphur dioxide can lead to serious health complications such as damage to the blood vessels, inflammation, and oxidative stress which trigger genesis of life threatening cardiovascular diseases such as heart attack and stroke.

Chaurasia: As global warming worsens, air pollution will persist. Recognising the link between heart disease and pollution is essential for public health advocacy and policy changes. Remember, prevention is key. Stay informed, protect your heart, and advocate for cleaner air.