Noxious air quality impacts everyone. But some people are more vulnerable to the health impacts of air pollution than others. One group is people with heart disease. Breathing in tiny, microscopic air pollutants damages your blood vessels over a period of time and makes them narrower and harder. It also puts immense strain on your heart muscle as it works overtime to supply oxygen. A recent study provided more evidence about how people with heart disease — and more specifically, heart failure — are extremely vulnerable to air pollution-induced inflammation.
The researchers found that when heart failure patients are exposed to air pollution, they experience inflammation in two biomarkers: CCL27 (C-C motif chemokine ligand 27) and IL-18 (interleukin 18). However, no changes in those biomarkers took place in people without heart disease.
“These biomarkers rose in response to air pollution in people who already had heart disease, but not in patients who were heart disease free, showing that heart failure patients are not as able to adapt to changes in the environment,” said Benjamin Horne, principal investigator of the study and professor of research at Intermountain Health, in a press release.
“It’s important that individuals with known heart disease, including those diagnosed with heart failure, need to be especially cautious during periods of poor air quality. This includes exercising indoors, making sure to take their prescribed medications, and avoiding areas like roadways and highways where there’s a lot more traffic and pollution,” Horne added.
Horne and team analyzed the blood and other biological samples of 44 patients with heart failure and 35 people without heart disease. They drew blood from the study participants on days when there were lower levels of air pollution. They defined low air pollution as the levels of fine particulate matter (PM2.5) in the air being below 7 micrograms per cubic meter (μg/m3). The researchers also collected blood samples of the study participants on days when PM2.5 levels shot up to 20 μg/m3 or higher. Levels of air pollution increased mainly during wildfire events that occurred during summer and on cold days when air pollutants tend to get trapped in the lower atmosphere as warm hair pushes the pollutants closer to the ground.
Once the researchers collected multiple blood samples at different times of the year, they studied 115 proteins present in human blood that indicate elevated inflammation in the body.
“These findings give us some information about mechanisms in people with heart failure who are having inflammation and suggest they’re not as capable in responding to acute inflammation as people who are healthy,” Horne further explained in the press release.
The study findings were presented at the American Heart Association’s 2024 Scientific Sessions international conference in Chicago on November 16, 2024.
Epidemiologists estimate that the global prevalence of heart failure is over 64 million cases as of 2020. ” The most frequent causes of heart failure is ischemic heart disease (42.3% of all cases), followed by chronic obstructive pulmonary disease (37.0%), mitral valve disease (4.3%), aortic valve disease (3.4%), rheumatic heart disease (3.0%), myocarditis (2.6%) and endocarditis (1.4%),” researchers wrote in a study published in AME Medical Journal.
