City Pollution Increases Factors that Lead to Heart Disease

Living in a heavily polluted city center may lead to calcium build-up in arteries.

No one likes pollution, but new research indicates that pollution is more than just a nuisance—it may have drastic effects on our long-term health by contributing to the development of heart disease. In fact, according to a study published in the Journal of Internal Medicine, individuals who live in heavily polluted urban areas are twice as likely to suffer from coronary artery calcification (CAC) compared to their counterparts who live in less polluted urban and rural areas.

Coronary artery calcification refers to the build-up of calcium deposits—or plaque—in the inner lining of the arteries. Over time, CAC restricts blood flow and can eventually lead to coronary artery disease, also known as heart disease. Severe CAC can lead to a life-threatening event such as a heart attack. There are a variety of risk factors for CAC, including hypertension, high cholesterol, high blood pressure, obesity, diabetes, and genetics. Lifestyle choices such as tobacco, alcohol, and stress also contribute to CAC. Now, this latest research indicates that environmental causes may be at play as well.

The Danish study included 1,225 men and women between the ages of 50 and 60 years. Approximately 20 percent of the study participants lived in the centers of major Danish cities. None of the participants showed any symptoms of heart disease; however, 43 percent had CAC. Those who lived in city centers were 80 percent more likely to develop CAC than those living in other areas. Men, older individuals, smokers, and those with diabetes were more likely to develop CAC—but still, even after adjusting for those risk factors, individuals living in the city center—meaning they had a higher exposure to pollution—were more likely to develop CAC. The air pollution levels were three times higher in city center areas than other urban areas, and seven times higher than the levels in rural areas.

The researchers concluded that individuals who live in heavily polluted areas have a higher risk of developing CAC, and ultimately heart disease. So, what can you do if you’re a city dweller? For starters, limit your exposure and avoid exercising during heavy traffic hours and high pollution days. Many cities offer an index or alert system to indicate days with heavy particulates. Also, get involved—become an advocate for pollution controls in your city. Cleaner air benefits us all.

Reference:

Lambrechtsen J, Gerke O, Egstrup K, et al. The relation between coronary artery calcification in asymptomatic subjects and both traditional risk factors and living in the city centre: a DanRisk substudy. Journal of Internal Medicine. 2012; 271(5): 440-450.