Noise and air pollution linked to hypertension, poor heart health

Hyderabad: Haven’t most of us experienced headaches and irritation when stuck in traffic for a long time? The noise from honking, the fumes from auto exhaust, and the delay caused by the slowdown of vehicular movement—all add to the physical and psychological stress.

But that’s not all. Prolonged exposure to noise and air pollution caused by road traffic can escalate risks of developing hypertension, according to a recent study published in the ‘Journal of the American College of Cardiology.’

Study on noise pollution and hypertension

Researchers at the American College of Cardiology, USA, found this through a prospective study conducted using UK Biobank data from more than 2,40,000 people, aged 40 to 69 years, without hypertension at baseline. The risk was found to increase in tandem with the noise dose.

Over a median period of 8.1 years, the scientists followed up with the participants for data on how many people developed hypertension. They estimated road traffic noise based on the residential address and the Common Noise Assessment Method, a European modelling tool, as mentioned in the study.

The scientists also found that people who had high exposure to both traffic noise and air pollution had the highest hypertension risk, which shows that air pollution may have a role as well.

These associations were found to be held true even when researchers adjusted for exposure to fine particles and nitrogen dioxide.

“We were a little surprised that the association between road traffic noise and hypertension was robust even after adjustment for air pollution,” said Jing Huang, lead author of the study, and added, “It is essential to explore the independent effects of road traffic noise, rather than the total environment.”

Remedial measures

As remedial measures, the authors suggested policymaking that may alleviate the adverse impacts of road traffic noise, such as setting stricter noise guidelines and enforcement, improving road conditions and urban design, and investing in advanced technology on quieter vehicles.

Further studies to understand the pathophysiological means through which hypertension develops from road noise are underway.

Link between noise pollution & high BP

Corroborating the study, Dr. Sunil Kapoor, senior consultant cardiologist at Apollo Hospitals, Jubilee Hills, Hyderabad said, “Though we don’t have similar studies in India, nevertheless, it has been found that over a period of time, say six to eight years, incidences of hypertension is higher among people who live in a noisy, traffic-prone area compared to those who live in a quieter residential area. Persistent loud noise stimulates the sympathetic nerve, which increases the stress level and blood pressure. That’s why it is advised not to play very high pitch music at a loud volume in car stereo or even otherwise.”

Air pollution and cardiac ailment risk

“It’s not only about noise pollution but even air pollution has been linked to poor heart health and hypertension. The fine micro-particles from the air pollutants enter the body and deposit in the arteries of the heart and start the process of inflammation, atherosclerosis, and blockages in the arteries of the heart. So, those consistently exposed for a number of years to auto exhaust and air pollution from factories are definitely more at risk of developing hypertension and cardiac ailments. Therefore, wearing masks and protective hoods is advised while working in places high in air pollution,” adds Dr. Kapoor.