Living Close to Major Roadways Ups the Risk of Sudden Cardiac Death

Residing close to a major road ups the risk of sudden cardiac death, especially in women, a new study states.

Apart from noisy vehicles, people living very close to major roads also face the risk of developing a number of serious health problems. Studies have shown that health effects linked with roadways include premature deaths, reduced birth weight, cardiovascular disease, reduced lung function and asthma. Studies have also shown a modest increase in coronary heart disease risk among those living close to major roadways.

The latest study, by Brigham and Women's Hospital and Harvard Medical School in Boston, is the first to evaluate the impact of roadway proximity to the risk of sudden cardiac death.

"It's important for healthcare providers to recognize that environmental exposures may be under-appreciated risk factors for diseases such as sudden cardiac death and fatal coronary heart disease," said Jaime E. Hart, Sc.D., study lead author and an instructor in medicine at Brigham and Women's Hospital and Harvard Medical School in Boston, Massachusetts. "On a population level, living near a major roadway was as important a risk factor as smoking, diet or obesity."

To prove the hypothesis, the researchers looked at the data of 107,130 women, mostly white and of an average age of 60 years. The participants were a part of the Nurses' Health Study from 1986-2012. They calculated the residential distance to roadways and considered other factors like age, race, calendar time, cigarette smoking, physical activity and diet.

The researchers found that out of 523 cases of sudden cardiac death, living within 50 meters of a major road increased the risk of sudden cardiac death by nearly 38 percent as compared to those living at least 500 meters away. Each 100 meters closer to roadways was linked with a 6 percent increased risk of sudden cardiac death. In 1,159 cases of fatal coronary heart disease, the risk went up by 24 percent.

The exposure of the public to major roadways is similar to the major sudden cardiac death risk factor. The researchers, however, couldn't measure all the risk factors that could be linked with living close to a major road. 

They demand the need for further studies among men and women of various age groups, races and income levels as all the study participants were between middle-age to elderly, and of middle-upper socioeconomic class.

It is estimated by the Environmental Protection Agency that 35 million people in the United States lived within 300 meters of a major road in the year 2009 and a majority number of the people lived in close proximity to major roads worldwide.

"Regardless of where you live, adopting heart-healthy habits, such as maintaining a healthy weight, being physically active, eating nutritious foods, quitting smoking, and managing stress, can help decrease your risk of heart and blood vessel disease," said Hart, who is also an instructor at the Harvard School of Public Health. "Our next step is to try to determine what specific exposures, such as air pollution, are driving the association between heart disease and major roadway proximity."

The finding was documented in the American Heart Association journal Circulation.