People who live near a major roadway may be at risk for heart disease due to an unexpected cause – traffic noise.
While it may seem more likely that air pollution would damage the body’s cardiovascular system, a series of new research has found that “environmental noise is associated with an increased incidence of arterial hypertension, myocardial infarction, heart failure and stroke,” according to a study appearing in the Journal of the American College of Cardiology.
The ill effects of noise are particularly dangerous at night, according to the new study. Noise disturbances in the nighttime hours are linked to increased levels of stress hormones circulating in the body as well as oxidative stress that can damage the heart and arteries, resulting in high blood pressure.
While the study is new, the researchers bring together a collection of previous findings investigating the negative impact of environmental noise on humans and animals. The link between noise and poor heart health isn’t all new, yet previous medical research hadn’t pinpointed exactly why – on a molecular level – the connection existed.
In 2011, a group of researchers investigating the topic stated that, “The question at present is no longer whether noise causes cardiovascular effects, it is rather: what is the magnitude of the effect?”
Rising Blood Pressure, Stress
A review of observational studies suggests that regular exposure to nighttime noise can spur the body’s stress reaction. For example, one study “found a statistically significant association between nighttime aircraft noise and blood pressure.” Another study found a 14% increased risk of stroke for every 10 decibels of road traffic noise that a person was exposed to.
Yet another study discovered that traffic noise was linked to an increased heart rate and “arterial stiffness.” Some research has identified a link between night noise and diabetes symptoms, including blood sugar levels.
“In conclusion, more and more large studies of high quality find that traffic noise is associated with coronary heart disease and stroke, as well as with major risk factors for [cardiovascular disease], most importantly hypertension and metabolic disease,” conclude the study authors.
What Can Be Done
Living in the 21st century comes with the perks of a high-tech world and instant communication. But it also has its drawbacks – including some, like nighttime noise, that people may not even be aware of.
“With industrialization and globalization, the importance of new environmental factors, such as noise and air pollution, is becoming increasingly evident,” report the study authors.
The researchers point to noise insulation in buildings and along highways as practical solutions to creating a less noisy world. They also cite reducing speed limits and engineering quieter roads as a way to cut traffic noise. At the present, however, such tactics don’t appear to be enough to ward off the health detriments of today’s high-paced world.
“Because the percentage of the population exposed to detrimental levels of transportation noise is rising, new developments and legislation to reduce noise are important for public health,” the authors conclude.