TOPSHOT – People walk along a road near India Gate amid heavy smog in New Delhi on February 22, … [+]
Harmful air quality affects everyone. But some people are more vulnerable to the health effects of air pollution than others. One group is people with heart disease. Breathing in tiny, microscopic air pollutants damages your blood vessels over time and makes them narrower and harder. It also puts a lot of strain on your heart muscle as it works overtime to deliver oxygen. A recent study provided more evidence about how people with heart disease—and more specifically, heart failure—are extremely vulnerable to inflammation caused by air pollution.
The researchers found that when heart failure patients are exposed to air pollution, they show inflammation in two biomarkers: CCL27 (CC motif chemokine ligand 27) and IL-18 (interleukin 18). However, there were no changes in these biomarkers in subjects without heart disease.
“These biomarkers increased in response to air pollution in people who already had heart disease, but not in patients without heart disease, showing that patients with heart failure are not as able to adapt to changes in the environment,” said Benjamin Horne, director. study investigator and professor of research at Intermountain Health, in a news release.
“It is important that people with known heart disease, including those diagnosed with heart failure, should be extra cautious during periods of poor air quality. This includes exercising indoors, making sure they take their prescribed medication and avoiding areas like roads and highways where there is a lot more traffic and pollution,” Horne added.
Horn 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 study participants on days when there were lower levels of air pollution. They defined low air pollution as levels of fine particulate matter (PM2.5) in the air below 7 micrograms per cubic meter (μg/m3). The researchers also collected blood samples from study participants on days when PM2.5 levels reached 20 µg/m3 or higher. Air pollution levels rose mostly during wildfires that occurred during the summer and on cold days, when air pollutants tend to be trapped in the lower atmosphere as warm hair pushes 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 increased inflammation in the body.
“These findings give us some insight into the mechanisms in people with heart failure who are inflamed and suggest that they are not as capable of 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 International Scientific Sessions in Chicago on November 16, 2024.
Epidemiologists estimate the global prevalence of heart failure to be over 64 million cases by 2020. The most common causes of heart failure are 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.
