Living on busy roads raises risk of a stroke or heart attack: study

By Mark Waghorn via SWNS

Living on a busy road raises the risk of a stroke or heart attack, according to new research.

Noisy traffic triggers high blood pressure - one of the leading causes of cardiovascular disease.

Lead author Dr. Jing Huang, of Peking University in Beijing, said: "We were a little surprised the association was robust - even after adjustment for air pollution."

The symptomless condition, known medically as hypertension, affects more than a quarter of adults in the UK - around 14.4 million. A third have not been diagnosed.

Vessels can become blocked - cutting off blood supply to major organs.

The findings are based on 240,000 Britons aged 40 to 69 tracked for an average of just over eight years.

Those exposed to the constant sound of roaring engines, honking horns and wailing sirens were most prone to the life-threatening disorder.

The study in JAAC Advances also found likelihood rose in tandem with the "dose."

Results stood after neighborhood levels of toxic particles emitted by vehicles were taken into account.

But people who had high exposure to both noise and air pollution had the highest risk - showing the latter plays a role as well.

Dr. Huang said: "Road traffic noise and traffic-related air pollution coexist around us.

"It's essential to explore the independent effects of road traffic noise - rather than the total environment."

The Chinese team analyzed data from the ongoing UK Biobank study which contains in-depth genetic and health information from participants.

It's the strongest evidence to date linking traffic noise with high blood pressure. Previously, it was unclear whether air pollution played a bigger role.

It's exposure to road traffic noise itself that can elevate hypertension risk, said Dr. Huang. Previous studies failed to show a causal relationship.

So Dr. Huang and colleagues selected participants who were clear of hypertension at the outset - enabling them to look at outcomes over time.

They estimated road traffic noise based on residential address and the Common Noise Assessment Method, a European modeling tool.

The findings can support public health measures. They confirm that exposure to road traffic noise is harmful to our blood pressure, said Dr. Huang.

Policymaking may alleviate the adverse impacts as a societal effort, she said.

Initiatives could include setting stricter noise guidelines and enforcement, improving road conditions and urban design and investing in advanced technology on quieter vehicles.

Dr. Jiandong Zhang, a cardiologist at the University of North Carolina who was not involved in the study, said: "To date, this is the first large-sized prospective study directly addressing the effect of road traffic noise on the incidence of newly-diagnosed hypertension.

"The data provides a higher quality of evidence to justify the potential to modify road traffic noise and air pollution from both individual and societal levels in improving cardiovascular health."

Dr. Huang and colleagues are now carrying out follow-up field studies to better understand the biological mechanisms through which road noise affects hypertension.

Cardiovascular disease is the world's number one killer - claiming around 18 million lives a year.