Persistent asthma may take a toll on the heart, not just the lungs, a new study suggests.
When the respiratory condition is relentless, it appears tied to plaque in the carotid arteries, increasing the risk for heart attack and stroke, researchers say.
The carotid arteries — large arteries on the sides of the neck — carry blood to the brain.
In a study of more than 5,000 men and women, researchers found that people with persistent asthma had nearly double the odds of having plaque buildup in the carotid arteries, compared with those without asthma.
Persistent asthma was defined as using daily controller medications to control asthma symptoms, such as wheezing or shortness of breath.
The plaque may be a response to inflammation caused by asthma, the researchers noted.
"Inflammation also plays a big role in cardiovascular disease," said lead researcher Dr. Matthew Tattersall, an assistant professor in the department of medicine at the University of Wisconsin, Madison.
Tattersall cautioned, however, that this study cannot prove that asthma causes plaque buildup in the carotid arteries, only that the two may be connected.
People with persistent asthma — but not intermittent asthma — also had higher levels of markers of inflammation, compared with those without asthma. But that might not entirely explain the increased plaque, Tattersall said.
"There are other things, too, that could cause people with asthma to have an increased risk of developing plaque," he said. "Our initial thought was that it was all due to inflammation, but we didn't see any change in our findings when we tried to adjust for that. So that leads us to think there may be multiple factors that increase cardiovascular risk."
Plaque buildup may also be related to the severity of asthma and how long someone has suffered from the condition, Tattersall said.
For the study, Tattersall's team used data from the Multi-Ethnic Study of Atherosclerosis conducted by the U.S. National Heart, Lung, and Blood Institute.
The investigators found that 67% of those with persistent asthma had plaque buildup in their carotid arteries. This compared to about 50% of those with intermittent asthma and those without asthma, according to the report.
Tattersall said people with continuous asthma should be sure to keep their asthma controlled. They also must be mindful of cardiovascular risk factors they can control, such as diet, exercise, and keeping their blood pressure, cholesterol and body weight low.
"In 2019, the American Heart Association came out with guidelines for the primary prevention of cardiovascular disease," Tattersall said. The guidelines note that people who have what they call risk-enhancing conditions — like inflammatory conditions — may be at higher cardiovascular risk, and that should be factored into decision-making by their clinician, he added.
"Our data really supports this idea that people with all variety of inflammatory conditions should be considered in that risk-enhancing group," Tattersall said.
Approximately one in 10 adults in the United States has asthma, said Dr. Gregg Fonarow, interim chief of cardiology at the University of California, Los Angeles. "Chronic inflammation is thought to play an important role in both asthma and cardiovascular disease," he said.
"This new study demonstrates that individuals with persistent asthma have a greater burden of atherosclerotic plaques in their carotid arteries. They also had increased levels of inflammatory markers that may play a role in both asthma and the initiation and propagation of atherosclerosis," he added.
This study highlights the link between asthma and cardiovascular disease, Fonarow said.
"Whether specific anti-inflammatory therapy would offer benefit requires further study," he concluded.
The report was published online Nov. 23 in the Journal of the American Heart Association.
For more on asthma, head to the American Lung Association.
SOURCES: Matthew Tattersall, DO, assistant professor, department of medicine, University of Wisconsin, Madison; Gregg Fonarow, MD, interim chief, cardiology, University of California, Los Angeles; Journal of the American Heart Association, Nov. 23, 2022, online