New studies add to mounting evidence that air pollution is a risk factor for heart disease. The most recent, shows the risk of dying from heart disease is greater than from lung-related illnesses when exposed to air pollution long-term.
Researchers say the findings confirms recent studies that show air pollution provokes inflammation not only in the lungs but inflammation which also speeds hardening of the arteries, and affects heart function. Those negative effects are much greater in smokers.
The study showed that for every increase unit in air pollutant measure, the risk of death caused by heart disease in major U.S. cities rose by 8% to 18%, and heart disease death posed a much greater threat to people living in polluted areas than lung disease.
The results appear in the Dec. 16 rapid access issue of Circulation: Journal of the American Heart Association.
Air Pollution Hurts Heart too
In the study, researchers linked data on risk factors and death collected from about half a million people who participated in the Cancer Prevention Study II by the American Cancer Society to information on air pollution from the U.S. Environmental Protection Agency.
Researchers focused on fine particulate matter air pollution, microscopic particles in the air that measure less than 2.5 micrometers in diameter, which is about the size of cigarette smoke particles.
Between 1982 and 1998, 22.5% of the people involved in the study died, and researchers found a clear association between air pollution and death rates.
For every increase of in air pollutants of 10 micrograms per cubic meter of air, the risk of all heart disease and diabetes rose by 12% and heart disease alone rose by 18%.
Compared with people who had never smoked, researchers found former smokers had a 26% higher risk of death from heart disease and diabetes. Current smokers had a 94% higher risk of death from heart disease and diabetes for every increase in air pollutant measure.
Researchers acknowledge that air pollution is not the main cause of heart disease, and many other factors, such as diet and lifestyle, play a role. But a greater understanding about the link between air pollution and heart disease could have important implications.
"We might be able to reduce the underlying processes of some cardiovascular disease just by reducing the exposure to air pollutants. And possibly, there may be ways to mitigate the impacts of air pollution, such as anti-inflammatory medications or other interventions," says researcher C. Arden Pope, III, PhD, an epidemiologist at Brigham Young University in Provo, Utah, in a news release.