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 consists of people with heart disease. Breathing in small, microscopic air pollutants over time damages your blood vessels and makes them narrower and harder. It also puts a huge strain on your heart muscle as it works overtime to deliver oxygen. A recent study has 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 patients with heart failure are exposed to air pollution, they experience inflammation in two biomarkers: CCL27 (CC motif chemokine ligand 27) and IL-18 (interleukin 18). However, no changes in those biomarkers occurred in people without heart disease.
“These biomarkers increased in response to air pollution in people who already had heart disease, but not in patients who were free of heart disease, demonstrating that patients with heart failure are not as able to adapt to changes in the environment,” says Benjamin Horne, director of the study and professor of research at Intermountain Health, said in a press release.
“Importantly, individuals with known heart disease, including those diagnosed with heart failure, should take particular care during periods of poor air quality. This includes exercising indoors, making sure you take prescribed medications and avoiding areas such as roads and highways where there is a lot more traffic and pollution,” Horne added.
Horne and team analyzed the blood and other biological samples from 44 patients with heart failure and 35 people without heart disease. They took blood from the study participants on days when there was less air pollution. They defined low air pollution as the level of fine particles (PM2.5) in the air below 7 micrograms per cubic meter (μg/m3). The researchers also collected blood samples from the study participants on days when PM2.5 levels shot up to 20 μg/m3 or higher. Air pollution levels increased especially during wildfires that occurred in the summer and on cold days, when air pollutants tend to become trapped in the lower atmosphere as warm hair pushes the pollutants closer to the ground.
After collecting multiple blood samples at different times of the year, the researchers studied 115 proteins in human blood that indicate increased inflammation in the body.
“These findings give us some information about mechanisms in people with heart failure who have inflammation, and suggest that they are not as able to respond 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 Scientific Sessions 2024 international conference in Chicago on November 16, 2024.
Epidemiologists estimate that the global prevalence of heart failure will be more than 64 million cases in 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 and heart failure. valvular heart 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.