Previous research
had established a link between road noise and hypertension, but it was
difficult to determine whether the effects were due to noise pollution alone or
a combination of noise and air pollution. The new study was able to account for
the effects of air pollution, and still found a significant association between
road noise and high blood pressure.
The study was
conducted by Jing Huang, an assistant professor in the department of
occupational and environmental health sciences at Peking University in Beijing,
China. Dr. Huang notes that the robust association between road noise and
hypertension was somewhat surprising, given the fact that air pollution is
often a confounding factor.
Environmental Exposures May Increase Heart Disease Risk
The findings of
this study are consistent with recent guidelines from the European Society of
Cardiology, which suggest that environmental exposures, including high levels
of noise, may increase the risk of heart disease. It is important to note that
while this study establishes an association between road noise and high blood
pressure, it does not prove causation. Further research will be needed to
explore the mechanisms behind this link and to determine whether reducing
exposure to road noise can reduce the risk of hypertension and other
cardiovascular diseases.
High Blood Pressure Affects Nearly Half of US Adults
According to the Centers for Disease Control and
Prevention, almost half of adults in the United States, or 116 million people,
have hypertension. Hypertension is diagnosed when an individual has a systolic
blood pressure greater than 130 millimeters of mercury or a diastolic blood
pressure greater than 80 mmHg. It is important to note that even if an
individual is taking medication to manage hypertension and their blood pressure
improves, they would still have a hypertension diagnosis.
Road Traffic Noise Increases Risk of Hypertension
Researchers conducted a study on nearly 250,000 people between the ages of 40 and 69 who did not have hypertension at the start of the study. They estimated the level of road traffic noise near each participant's residential address using the Common Noise Assessment Method, a modeling tool developed by the European Commission.
After following the participants for a median of 8.1 years, they found that
over 21,000 people had developed high blood pressure. The study found that
people who lived in areas with more road traffic noise were more likely to
develop hypertension, and there was a "dose-dependent relationship"
between the level of road noise and the risk of hypertension. The louder the
noise, the greater the risk.
Potential Links between Noise and Hypertension
Dr. Jim Liu, a
cardiologist at The Ohio State University in Columbus, who was not involved in
this research, said that this study is interesting because it investigates the
link between noise and high blood pressure, which is not typically considered.
Dr. Liu notes that increased noise or pollution could lead to increased stress
on the body and cause elevations in blood pressure. Stress on the body can
cause physiological changes, such as sympathetic nervous activation, increased
inflammation, or fluctuations in adrenal gland hormones, which can affect blood
pressure.
What are some ways to reduce road traffic noise?
According to Liu,
taking steps to reduce traffic noise can help minimize its negative impact on
health, especially if the noise is bothersome. Chao suggests various methods
for noise prevention, including relocating to a quieter area, lowering the
volume of noise, or blocking the noise with better insulation materials or
hearing protection like earplugs or earmuffs.
She also advises
looking for devices with a good fit and a higher Noise Reduction Rating (NRR)
for better sound-blocking. In addition, Chao notes that some electronically
powered devices use active noise cancellation to cancel out sound waves.
However, she cautions against using noise machines or noise masking, as they
may only add to the overall volume of noise exposure.
