By AMERICAN HEART ASSOCIATION NEWS

It’s long been known that breathing poor-quality air is linked to an increased risk of heart disease and stroke. Studies also have found that racial and ethnic minorities are more likely to live in areas near factories, freeways and other sources of environmental pollutants.

A new study connects the dots between these findings, suggesting that black adults may be more likely than their white peers to die from cardiovascular disease in part because they breathe dirtier air.

The research, published Thursday in Arteriosclerosis, Thrombosis, and Vascular Biology, used outdoor air-quality data from 2003 to 2004 and 2012 to 2013 to estimate annual one-year average air pollutant exposure for 1,717 adults from western Pennsylvania participating in a long-term cardiovascular disease study called HeartSCORE. That stands for Heart Strategies Concentrating on Risk Evaluation. Two-thirds of the participants were women and 45 percent were black.

The researchers found black adults were more likely than their white counterparts to be exposed to air pollutants, including pollen and the invisible particles of materials found in construction sites. They also were more likely than white adults to breathe a sooty black material produced by coal-powered plants, diesel engines and other sources.

Additional analyses showed that exposure to the particles, but not to sooty black material, was associated with risk factors for developing heart problems, such as higher levels of blood sugar and blood vessel cell damage, which can lead to plaque buildup and blood clots.

The researchers said the findings suggest breathing these fine particles contributed in part to the increased risk for heart attacks, stroke and other causes of death seen over an eight-year period among African-Americans taking part in the study.

“This is a complex problem,” said Dr. Sebhat Erqou, the study’s lead author and a cardiovascular disease fellow at the University of Pittsburgh Medical Center Heart and Vascular Institute. “Bigger studies in different areas allowing us to make more generalizations in this line would be useful. So I think policymakers could encourage that.”

The findings add to the research on heart disease and racial and ethnic differences in exposure to air pollution.

A report last year from the U.S. Centers for Disease Control and Prevention concluded the overall risk of dying from heart disease increases 16 percent for each 10-unit increase in the concentration of fine particles a person is exposed to. It did not find disparities in exposure to fine particles and heart disease death rates among whites, blacks and Hispanics.

However, another study also published in 2017 in the New England Journal of Medicine that looked at air pollution and death rates in Americans enrolled in Medicare found black, Hispanic and Asian adults were more likely to die from breathing bad air.

Dr. Sanjay Rajagopalan, the chief of cardiovascular medicine at University Hospitals Cleveland Medical Center and a co-author on the American Heart Association’s 2004 and 2010 reports on air pollution and cardiovascular disease, said the findings from the new study confirm those from others that suggest exposure to fine particles and sooty material are associated with risk of heart disease and stroke.

Rajagopalan, who was not involved with the current study, said it stands out among others because researchers looked at the health effects of those pollutants in a large sample of black adults.

“The burden of disease attributable to air pollution is large,” said Rajagopalan, who also is the director of the cardiovascular research institute at Case Western Reserve University. The scientist is working on a China-based study investigating the effectiveness of masks in reducing exposure.

Erqou and Rajagopalan said, in general, health care providers should be aware that some of their patients may be at a higher risk of developing heart disease and stroke because they have greater exposure to pollutants.

Short of telling patients to move out of neighborhoods with unhealthy air, Erqou said there’s not much health care providers can do to help their patients reduce their exposure to bad air. Mostly, he said, the best things providers can do is try to offset this risk by encouraging their patients to follow the tried-and-true advice for staving off heart disease and stroke: exercise, eat right and don’t smoke.

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