Living near a major road has been found to increase women's risk of sudden death.

In the past researchers had found an association between living near large roads and coronary heart disease risk, but this study was the first to look at how it affected chances of cardiac death, the American Heart Association reported.

"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, study lead author and an instructor in medicine at Brigham and Women's Hospital and Harvard Medical School in Boston. "On a population level, living near a major roadway was as important a risk factor as smoking, diet or obesity."

To make their findings the researchers looked at 107,130 women who were predominantly white and had an average age of 60 who were part of the Nurses' Health Study between the years of 1986 and 2012.

Over the course of the study there were 523 cases of sudden cardiac death. Patients who lived within 164 feet of a major road were found to be 38 percent more likely to die from this cause than those who lived 0.3 miles away. Every 328 feet of distance between the patient's residence and the major road was associated with a 6 percent difference in cardiac death risk.

"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 findings were published in a recent edition of the journal Circulation.