Noisy workplaces bad for the heart, says new study

[Guest guest]

Another reason to tell people to shut up.

Aspies probably already knew what this article is reporting.

Administrator

http://news.sympatico.ctv.ca/home/noisy_workplaces_bad_for_the_heart_says_new_st\

udy/bad6c8ce

Noisy workplaces bad for the heart, says new study

05/10/2010 8:26:05 PM

CTV.ca News Staff

If jackhammers and jetliners make up the ambient noise at your work place, take

note: working in a persistently noisy environment can more than double your risk

for heart disease, a new study has found.

And the risk is even higher, researchers say, for male workers under age 50 who

smoke.

Researchers at the University of British Columbia, who conducted the study,

cannot say exactly what it is about loud noise at work that is so bad for the

heart.

" The exact reasons are not known right now, " lead researcher Wenqi Gan told

CTV.ca in a telephone interview from Vancouver. " But people believe that it is

through psychological stress. "

Gan and his colleagues suggest that the effect of consistently loud noises on

the body is similar to the effect of a stressful event, such as a sudden

powerful emotional crisis, which activates chemicals in the body that restrict

blood flow through the coronary arteries.

The findings are published in the online edition of the journal Occupational and

Environmental Medicine.

For their study, Gan and his team analyzed data from the U.S. National Health

and Nutrition Examination Survey, taken between 1999 and 2004. They included

data from more than 6,300 study subjects who were aged 20 or over and who were

employed at the time they were surveyed.

Slightly more than 20 per cent of the study subjects reported having been

exposed to occupational noise over a median time period of 8.8 months. For the

study, loud noise was defined has making it necessary to speak in a loud voice

or shout to be heard. Of those who worked in noisy environments, more than 83

per cent were male, with an average age of 40.

" Based on this study we found that workers exposed to loud occupational noise

had a two- to threefold increase in the prevalence of coronary heart disease, "

Gan said. " This association is particularly strong for younger workers under 50,

for men, for current cigarette smokers. "

Workers under age 50, more than 4,500 of the study subjects, were between three

and four times as likely to have angina or coronary artery disease, or to have

had a heart attack. Male workers in this age group who also smoked were also at

a greater risk for heart problems, the researchers found.

The workers did not have unusually high levels of cholesterol or inflammatory

proteins, which are indicators of heart disease risk, Gan said. But the

researchers did find that workers exposed to loud noise at work were twice as

likely to have isolated diastolic hypertension, or IDH, which measures the

pressure of the artery walls when the heart relaxes between heartbeats. IDH is a

risk factor for heart problems.

According to Gan, there are limitations to the study. For instance, because it

only included subjects employed at the time of the survey, there is no way to

gauge how noise exposure may contribute to heart disease even after a worker

leaves a job. Other workers who developed heart disease may also have died

before the survey was conducted.

" So the effect estimates based on the cross-sectional studies may underestimate

the true adverse effects (of workplace noise), " Gan said. " So, although based on

this study we found that the effect is really large, the true effects may be

much larger. "

For those who are wondering if their job poses a health risk, a U.S. study using

the same data found that workplace noise is highest in mining, followed by

lumber and wood production. Other high-risk occupations include repair and

maintenance jobs, motor vehicle operation and construction.

Gan said workers in noisy environments should take steps to mitigate noise

levels by using ear plugs or other hearing-protection devices. But because the

ability of ear plugs to mute noise is limited, Gan said employers must do their

part to make workplaces safe for their employees.

" Managers should pay attention to this issue, " Gan said. " Even if it's expensive

to perform engineering noise control, I think it is worth it. "