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Road rage is aggressive driving caused by anger or stress behind the wheel. Most people are familiar with it. The honking of the horns and revving engines can not only affect the people in the vehicle, but it can also increase blood pressure for those living nearby.
Research had previously shown that road noise can increase hypertension risk -- high blood pressure. However, it wasn't clear if it was noise from traffic or pollution. Researchers now have evidence to support this conclusion.
Researchers used data from the UK Biobank's biomedical database UK Biobank to analyze data from over 240,000 people aged 40-69 who didn't have hypertension at first.
The American College of Cardiology team used residential addresses as well as a European modeling tool called the Common Noise Assessment Method. They then looked at follow up data for a median of 8.9 years to determine how many people had high blood pressure.
Researchers were surprised by the results published Wednesday in JACC: Advances. High blood pressure was more common in people living near traffic noise. Researchers also found that the risk of developing high blood pressure increased with increasing noise levels, even after adjusting for fine particles and nitrogen dioxide.
Hypertension is more likely to occur at higher noise levels
Kazem Rahimi (senior author), professor of cardiovascular medicine at Oxford and population health, said to CNN that noise pollution can lead to high levels of air pollution. This raises the question of whether they are contributing individually to the risk. Living in polluted areas and noisy places increased the risk of hypertension.
However, this doesn't mean that air pollution isn't a factor in hypertension. Those with high levels of exposure to road noise and pollution were at greatest risk.
"We didn't detect any threshold above which the risk began to increase," Rahimi said. Rahimi stated that the risk of developing a hearing loss increased when noise levels were higher, beginning at the lowest category measured in the study. This was 10 decibels.
Rahimi explained to CNN via email that the association was graded. This means that the greater the noise level, the higher the risk of hypertension in future.
Rahimi said that policymaking toward road traffic noise control would be a societal effort. This could include setting stricter noise guidelines and enforcement, improving roads conditions, and investing in advanced technology for quieter vehicles like EVs (electric cars).
According to the World Health Organization, 1.28 billion people aged between 30-79 years have hypertension. Two-thirds of these people live in low- or middle-income countries.
According to the Centers for Disease Control and Prevention, hypertension increases the risk of stroke and heart disease, two of the leading causes of death in America. According to WHO, 46% of adults don't know they have hypertension.
WHO states that high blood pressure can be caused by genetics, older age, obesity, inactivity, excessive alcohol intake, and overweight.
The condition is usually not symptomatic so it's best to have your blood pressure checked to determine if it's present.