A new study by heart researchers at Intermountain Health finds that Utahns with heart disease, specifically those with heart failure, are especially vulnerable to the impacts of air pollution and poor air quality caused by seasonal winter inversions and wildfire smoke and should take steps to protect themselves.  

In the study, researchers found that two inflammatory markers — CCL27 (C-C motif chemokine ligand 27) and IL-18 (interleukin 18) — were elevated in heart failure patients who were exposed to poor air quality, but did not change in those without heart disease. This indicates that such air pollution events put more strain on the bodies of patients who already have heart problems.

While previous research has shown that people with some chronic health conditions, like heart failure, coronary disease, asthma, and COPD, struggle during spikes in air pollution, the new Intermountain Health study demonstrates that cardiac inflammation levels specifically rise in people with heart disease during periods of poor air quality.  

“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, PhD, principal investigator of the study and professor of research at Intermountain Health. 

 For the retrospective study, Intermountain Health researchers worked with scientists at Stanford University and the Harvard School of Public Health to examine the blood of patients enrolled in the Intermountain INSPIRE registry, which collects blood and other biological samples, medical information and laboratory data from healthy individuals and those who have been diagnosed with a variety of medical conditions. 

 Researchers specifically looked at blood tests for 115 different proteins that are signs of increased inflammation in the body.

They then examined blood draws of 44 patients with heart failure with preserved ejection fraction, and 35 people without heart disease. Some blood was drawn on days with low air pollution, where ambient PM_2.5levels were under 7 micrograms per cubic meter (μg/m³) of air; those test results were compared to draws done in other people on days when air pollution spiked to PM_2.5 levels of 20 μg/m³ or over. 

These spikes were caused by either wildfire smoke in the summer, or during a winter inversion, where air pollution is trapped when warm air holds pollution closer to the ground.

Researchers found that two inflammatory markers — CCL27 and IL-18 — were elevated in heart failure patients, but did not change in those without heart disease, indicating that such air pollution events put more strain on the bodies of patients who already have heart problems.

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,” said Dr. Horne. 

He added that the results from the study suggest that heart failure patients need to take extra precautions during times when air pollution is high.

“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,” he said. 

 Results of the study were presented at the American Heart Association’s national Scientific Session international conference in Chicago. 

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While coronary heart disease and diabetes are often seen in the same patients, a diagnosis of diabetes does not necessarily mean that patients also have coronary heart disease, according to a new study from researchers at Intermountain Health in Salt Lake City.

The Intermountain study found that proactively screening patients with diabetes 1 and 2 for coronary heart disease who have not shown symptoms of heart problems does not improve long-term mortality rates, nor does it lower the chance of them having a heart attack or stroke in the future.

“Our study found that doing these kinds of screenings on patients doesn’t make any marked difference in their long-term survival rates,” said J. Brent Muhlestein, principal investigator of the study and co-director of cardiovascular research at Intermountain Health.

“Instead, results of our study reinforce that we should be focusing on other proven interventions for people with diabetes, like medication management, diet and exercise, to help these patients lead long and healthy lives,” he added.

Findings from the Intermountain Health study were presented at the American Heart Association’s Scientific Sessions 2024 in Chicago on Monday, November 18.

For the study, Intermountain Health researchers examined data from FACTOR-64 study, a randomized clinical trial of 900 people with type 1 or type 2 diabetes for at least three to five years without coronary artery disease symptoms.

Of these patients, 452 were screened with a coronary computed tomography angiography (CCTA), which uses a powerful X-ray to make a 3D image of the heart. Researchers compared

these patients with a control group of 448 people who were treated with standard optimal diabetes care guidelines.

Enrollment occurred between July 2007 and May 2013, and followed up on in May 2024.

Researchers found that using CCTA to screen for cardiovascular disease did not significantly affect the rates of all-cause mortality or of non-fatal heart incidents, like heart attack and stroke. This was true when researchers initially followed up four or five years after the CCTA screening, and again at 12 years.

“These findings should discourage the use of CCTA for screenings in diabetes patients who do not show any symptoms of heart disease,” said Dr. Muhlestein.

“While our study showed that screening for coronary heart disease with CCTA won’t make any difference, it did show that if patients carefully medically manage their diabetes, they may live almost as long as somebody who does not have diabetes, which wasn’t the case before,” said Dr. Muhlestein. “This study shows that, even over an extended period of time, a screening like this can’t replace those kinds of critical behaviors.”

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