World IBD Day 2021

Aditi Karnad

Heart health and the climate crisis: exploring the links between two of the biggest issues at stake today

29 September 2022

blue sky full with clouds featuring one heart shaped cloud

Cardiovascular disease and climate change are two major challenges to public health, but they are not separate issues. This World Heart Day, it’s time to recognise what connects them.

Cardiovascular disease (CVD) is one of the biggest challenges facing societies today. It is the leading cause of death worldwide: it was responsible for 17.9 million deaths in 2019, and accounts for 32% of all deaths. In some countries, the CVD-related death toll is actually rising – largely as a result of an increase in both medical and environmental risk factors.

And, of course, it’s not just non-communicable diseases that kill people. Every year, more than 5 million deaths across the world are associated with exposure to extreme cold or extreme heat. Meanwhile, the burning of fossil fuels produces greenhouse gases (major contributors to climate change) and other airborne pollutants, and caused 9 million deaths worldwide in 2015.


Climate change and CVD: a two-way interaction

Climate change and air pollution contribute to increased risk and severity of CVD; more than 20% of all CVD-related deaths are associated with air pollution. Extreme heat can also have numerous negative effects on the cardiovascular system – it can cause high or low blood pressure and irregular heartbeat, and can even trigger heart failure.

The interaction between climate change and CVD works both ways. Intensive care treatment, which may be required for people following a heart attack or stroke, is a major source of greenhouse gas emissions, contributing to almost 5% of global emissions in 2018. Air travel, by comparison, contributed 1.9%. Given the substantial burden of CVD, finding ways to reduce hospital admissions could significantly contribute to efforts to combat climate change.

So, with this two-way interaction in mind, what opportunities are there to improve care and quality of life for people with CVD while also reducing damage to the environment?

Intensive healthcare delivery is a major source of global greenhouse gas emissions, contributing to almost 5% in 2018. Air travel, by comparison, contributed 1.9%.


Preventing CVD will reduce its burden on people and the planet

The majority of CVD cases can be prevented. Personal risk factors – such as unhealthy diet, physical inactivity, smoking and excessive drinking – can all be modified, by creating environments that are conducive for making healthy choices affordable, and investing in services such as smoking cessation programmes.

Conditions such as high blood pressure, diabetes, high cholesterol and obesity can increase a person’s risk of developing CVD. These can largely be monitored and treated in primary care, reducing the need for hospitalisation.

Researchers in the US have identified some ‘high-yield interventions’ that could not only help prevent CVD but reduce net greenhouse gas emissions at the same time. These interventions include moving from high-red-meat diets to plant-based diets, facilitating active transportation (e.g. walking and cycling), expanding green spaces and transitioning to clean energy sources.

Female doctor talking to older woman and man

Bringing care closer to home, by ensuring community healthcare services are appropriately equipped, would be less resource intensive – reducing travel emissions and improving patient outcomes.


Optimising CVD care pathways can deliver more efficient care

Preventing hospital admissions by creating efficient care pathways and reducing wasteful practices would not only provide an opportunity to improve people’s health, but could also reduce carbon emissions. Long-term, resource-intensive hospital stays are a major contributor to greenhouse gas emissions. In the UK, an average overnight stay in a hospital ward for a patient requiring more intensive treatment produces around 2.3 times more greenhouse gas emissions than a stay in a ward with lower-intensity treatment.

It’s also important to focus on secondary prevention – the careful management of risk factors in people who have experienced a heart attack or stroke, in order to prevent a subsequent one. Second or subsequent heart attacks and strokes often require longer hospital stays and more diagnostic tests and treatments, adding to the environmental burden.

Bringing care closer to home, by ensuring community healthcare services are appropriately equipped, would be less resource intensive. It would also reduce travel emissions and improve patient outcomes. Community-based care could be facilitated by broader adoption of digital health, such as remote monitoring and teleconsultations.


Seeing the whole picture

Although we may often think of different policy priorities as ‘competing’ with one another, it’s important to recognise that no area of policy – health, environmental, economic – exists in isolation. As we’ve seen, cardiovascular disease and climate change are among the most pressing concerns facing governments today. There’s never going to be a ‘silver bullet’ to fix these problems instantly, but taking a holistic view and recognising where different priorities overlap can help us to find solutions.

Improving CVD prevention and care will clearly have a beneficial impact on people’s lives. Given the enormous burden of CVD, this will translate into broader societal benefits, as people are able to remain healthy as they age, maintaining physical and financial independence for longer. Finally, keeping people out of hospital will have a sizeable impact on the healthcare sector’s use of resources, saving costs and – crucially – reducing the environmental burden. Given the urgency of the climate crisis, we can’t afford to wait.


This is the third in a series of HPP blogs around healthcare and climate change. Read the first instalment on the nexus between climate change and healthcare, and the second on how climate change is affecting maternal and fetal health.


The opinions expressed in this blog are those of the author and do not necessarily represent the views of The Health Policy Partnership.