Extreme heat, smoke and noise can strain the heart and lungs

Older adults, Māori and Pacific peoples are among the people most at risk from environmental stressors on the heart, according to the Cardiac and Respiratory Foundation.

The foundation lists extreme heat, bushfire smoke, noise pollution, chemical pollution and climate-related disasters as stressors. Its article is the second in a series on the environment and the body’s organs, and the first looked at air pollution.

New guidance from the European Society of Cardiology, American College of Cardiology, American Heart Association and World Heart Federation confirms these wider stressors are now recognised as contributors to cardiovascular disease. They sit alongside smoking, high blood pressure, diabetes and high cholesterol.

The heart and lungs work together to supply oxygen around the body, the foundation says. Environmental stressors can add to the workload of both organs through inflammation, oxidative stress, damage to blood vessels, and changes to the nervous system that regulates heart rate and blood pressure.

These changes can raise the risk of heart attack, stroke, heart failure, high blood pressure and cardiac arrhythmias such as atrial fibrillation, the foundation explains. Worsening respiratory conditions put extra strain on the heart too.

In hot weather, the body works harder to cool itself by sending more blood to the skin and producing sweat, the foundation says. That can strain the heart and may raise the risk of dehydration, low blood pressure and heat exhaustion, particularly for older adults and people taking medicines such as diuretics.

Bushfire smoke and other extreme weather add to the burden, the foundation notes. During climate-related disasters, poor air quality combines with the stress of heat, disrupted routines and reduced access to care.

The foundation says environmental health risks do not affect everyone equally. Those at greatest risk are people living with heart disease or stroke, older adults, people with chronic respiratory disease, and people with diabetes or multiple long-term conditions.

The list also includes Māori, Pacific peoples and communities experiencing health inequities. So do people with limited access to cooling, housing or healthcare during extreme weather events.