Killer Traffic: Roadway Noise Linked to Increasing Heart Attack Rates
Posted by Liz Ernst on Thu, Jun 28, 2012 @ 01:35 PM
Noise, normally defined as 'unwanted sound, has been redefined by the Luxembourg-based Expert Panel on Noise (EPoN) as such: Noise is audible sound that causes disturbance, impairment or health damage.
I find it to be a pretty profound assertion in light of the many studies regarding the effects of noise on health – particularly heart health – published in recent decades that all conclude in varying degrees that noise is killing us. It reminds me of all the years the tobacco companies were pussy-footing around the dangers of cigarette smoking. For decades they got away with ambiguous public health warnings like "Cigarette smoking may be hazardous to your health," and suddenly someone put their foot down and made them change the labels.
"Warning: Cigarette smoking causes lung cancer, heart disease and emphysema."
It looks like researchers just keep fiinding new information about the adverse health effects of noise, and it's definitely squirm-worthy.
A new study conducted by physicians from the Danish Cancer Society and published in the Public Library of Science (PLoS ONE) - a scientific journal out of the UK - found a “clear relationship” between noise and escalated risk for heart attacks. The PLoS ONE study of more than 50,000 Europeans produced some grim findings for residents of our noisy planet: with every 10 decibel rise in volume over 60 decibels, the risk of heart attacks to folks exposed to the noise source increases by 12 percent; 80 decibels translates to the sound of an annoying buzzing alarm clock - not as loud as you'd expect from a decibel level capable of contributing to heart disease, right?
So if you're exposed to noise even louder than an annoying alarm clock for long stretches of time in your day-to-day life, your heart is taking a beating and you may not even realize it.
The link, according to study leader Mette Sorenson, Ph.d., looks to be noise-induced stress causing sleep disturbances - sleeps disturbances play a significant role in the noise-heart attack cocktail. Sorenson was actually more specific, pointing to high traffic noise as the stress inducer that leads to sleep disturbances, that lead to an increased risk of heart attack.
There have been plenty of studies in recent decades measuring the effects of noise on health. Some studies have already claimed that noise might be a contributing factor to heart attacks, but few were willing to step out on the limb and slap a scary warning sign on noise, until now anyway. Noise is inescapable in too many places. People are so conditioned to living with noise, there hasn't been an urgency to do something about it until very recently when too many of us realized we were losing our hearing, losing our ability to think clearly in a crowded restaurant, get a good night's sleep; plus, the anti-noise movement has became more and more visible. In the Danish study, the test group was massive - 50,000 people, and researchers claim they found conclusive evidence of an association between residential exposure to road traffic noise and heart attack risk. Of course it has to be road traffic, the most ubquitous noise source on earth, instead of something you can avoid, like sonic booms in the Everglades.
Life isn't always fair, let's face it.
I worry about the effects of noise on my heart all the time. My father, brother, and sister all died of heart attacks; my brother and sister at inexplicably young ages, non-smokers and seemingly healthy. Just last week, my brother-in-law suffered a fatal heart attack at age 63, and he never smoked a cigarette in his life. He’d had a first heart attack about 10 years ago, and ignored his physician’s recommendations for bypass surgery.
As I’ve said before, writing about the health related ramifications of noise over the past three-plus years has turned me into a bit of a hypochondriac, compounded by the fact that I just moved into a duplex directly under the flight path of a major U.S. air force base. But I feel fine, really.
So, according to Sorenson, this study narrowed the noise-heart attack association to none other than regular residential exposure specifically to road traffic noise, which is the noise source on which she based the 10-decibel increase / 12 percent higher risk to the well being of our tickers.
“It shows a clear dose response relationship,” she was quoted telling a Daily Mail reporter.
And, if that's not enough to send you searching for an isolation chamber you can cart around with you, according to another recent study by the World Health Organization (WHO), noise from rail and road transport is linked to 50,000 fatal heart attacks every year in Europe and 200,000 cases of cardio-vascular disease.
That bears repeating: 50,000 fatal heart attacks annually, and 200,000 cases of cardio-vascular disease – and these are the numbers that can definitely be linked to noise, accounting for roughtly 10 percent of Europe’s health care budget.
WHO researchers claim that slightly less than two percent of heart attacks in high income European countries can be attributed to traffic noise levels higher than 60 decibels. Still, cardiovascular disease is the largest cause of death in the EU and accounts for approximately 10% of national healthcare budgets.
Sorenson gives us reason to hope though, by stating that sleep disturbances in and of themselves can contribute to cardiovascular disease risk, which would lead to a hypothesis that exposure to noise during the night might be more harmful than daytime exposure. So maybe the answer is to sleep in a quiet place?
Sorenson also pointed out that that changes in lifestyle caused by disrupted sleep could play a role in the heightened risk of heart attack as well. For instance, she says that stress and sleep disturbances can cause changes to lifestyle habits, including increased tobacco smoking, thus a potentially stronger association between traffic noise and heart attack among smokers.
Hmmmmm...
But before we all breath a collective sigh of relief and go back to blaming heart attacks solely on cigarettes and poor sleep habits, Sorensen said her study did indeed find indications of an escalated rate of heart attacks in people subjected to road traffic noise who never smoked. Gotcha!
The population targeted for this study consisted of people who lived mainly in urban areas, and researchers did not rule out that other factors could be at play. But they kept coming back to traffic noise as the real culprit.
"Traffic noise in cities is an important public health issue,” said Ann Stauffer of the Health and Environment Alliance headquartered in Brussels, Belgium.
In addition, evidence shows that noise escalates incidents of stroke, especially in the older population, and affects children’s ability to learn.
New data on the harm noise is reaping on our bodies is surfacing every day it seems. The next step is to raise the awareness flag, get medical professionals in on the discussion, and become activists for establishing effective anti-noise legislation. People need to become proactive about lowering the planet's decibel levels.
And find a place to sleep that's quiet, if you can. Go on, save yourselves!
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