UW Will Study Link Between Air Pollution, Heart Disease in EPA $30 Million Grant
The Environmental Protection Agency announced July 29 that it is awarding its largest research grant ever-$30 million to the University of Washington to study the connection between air pollution and the No. 1 cause of death in the United States: cardiovascular disease.
The 10-year study will see if long-term exposure to fine particles in the air is associated with changes in atherosclerosis (buildup of plaque in the arteries) and other factors associated with heart disease.
Particulates come from a variety of sources including coal-burning power plants, factories, construction sites, cars, trucks, buses, tilled fields, unpaved roads, stone crushing and the burning of wood. Other particles may be formed when gases emitted from burning fuels react with sunlight and water vapor.
This is the first major study designed to look at the chronic impacts of long-term exposure to air pollution on cardiovascular health. "There's a lot yet to be understood about what explains cardiovascular disease besides the known factors such as high cholesterol, hypertension and diabetes. There are still many unexplained variations in who gets heart disease, and when they get it. Some of the explanation is likely to come from studying environmental factors," says Environmental and Occupational Health Sciences Professor Joel Kaufman. "We hope this study will really define the contribution of particulate air pollution to cardiovascular disease."
Researchers will follow study participants for 10 years. About 8,700 people will be recruited in nine communities in California, Illinois, New York, North Carolina, Maryland and Minnesota. Many of the people expected to participate are already enrolled in other studies of cardiovascular health.
Prior studies that included pollution and cardiovascular disease were originally designed to study other factors. They were either not originally designed to study heart disease or not originally designed to study air pollution, says Kaufman, who is the project's lead investigator.
"You could look at those previous studies and say it's as simple as 'Shouldn't we just have less pollution?' In a sense it is really that simple-and the current scientific evidence is clear enough to take action for cleaner air. But some people have raised questions about whether the existing studies really form a strong enough scientific basis to be regulating against pollution. This study is designed to answer those questions," Kaufman says.
One of the weaknesses of most previous studies was that their researchers could only assume everyone in a particular city has the same exposure to pollution, Kaufman adds. In fact, that's not true. Exposures vary within a metropolitan area. Pollution varies in a community depending on such variables as wind direction, geographic features and proximity to highways or other sources of pollution.
The study will use existing air quality monitors in the cities under study, but also use new monitoring networks to characterize air pollution exposures down to the level of the neighborhood. The researchers will use a limited number of home and even personal monitors to estimate participants' pollution exposures. For example, the researchers will test exposures by putting monitors outside the homes of about 3,600 participants at certain times.
The study will be based at the UW in Seattle, and will include faculty from the UW departments of environmental and occupational health sciences, biostatistics and epidemiology in the School of Public Health and Community Medicine, as well as the departments of medicine, statistics, geography and civil and environmental engineering.
Collaborating institutions include UCLA, Columbia, Northwestern, the University of Minnesota, Johns Hopkins, Wake Forest, the University of Vermont; Tufts-New England Medical Center and the University of Michigan.
Kaufman, an attending physician in internal medicine, is also director of the UW Occupational and Environmental Medicine Program, associate professor of medicine, and an adjunct associate professor of epidemiology.