Second-hand smoke may hamper circulation
CNN, Wednesday, 7/25/01
Non-smokers are harmed by even brief exposures to passive
smoke, according to a study published Tuesday in the Journal
of the American Medical Association.
The journal's editors said in an editorial the study suggests that
"everyone should be protected from even-short term exposure to
the toxins in second-hand smoke."
"Communities should continue to require that workplaces, including
restaurants and bars, be smoke-free and mount public education
campaigns to encourage smoke-free homes. Not only will everyone
breathe better, but they will also have healthier hearts," the editorial
said.
In the study, a group of doctors from Osaka City University Medical
School in Japan studied 30 Japanese men -- 15 smokers and 15
non-smokers.
The men spent 30 minutes in the Osaka City University Hospital
smoking room.
They were then tested to see how well endothelial cells in the hearts
of the men were working. Endothelial cells -- which line the heart and
blood vessels -- contribute to increased blood flow and inhibit the
formation of blood clots.
When their function is impaired, they contribute to narrowing of blood
vessels, restricting the flow of blood, and contributing to hardening of
the arteries.
The Osaka City study showed that after only short periods of
exposure, passive smoke had "abruptly reduced" the function of
endothelial cells in non-smokers.
"This provides direct evidence of a harmful effect of passive smoking
on the coronary circulation of non-smokers," the study's authors said.
Smokers, who smoked more than 20 cigarettes a day and whose
endothelial cell function was already depressed, did not suffer the
same sharp drop in cell function from passive smoke.
In 1992, the American Heart Association concluded that the risk of
death due to heart disease is increased by about 30 percent among
those exposed to environmental tobacco smoke at home, and could
be higher in those exposed at the workplace when tobacco smoke
is present.
The new study's findings "are important not only because they
illustrate the importance of preventing nonsmokers from any
exposure to second-hand smoke, but also because they help to
explain the relatively large risk of death and other cardiac events
associated with passive smoking compared with active smoking,"
said the editorial, written by Stanton A. Glantz and Dr. William
Parmley, of the cardiology department at the University of California
at San Francisco. Glantz is a prominent anti-smoking advocate.
Though cigarette makers have not acknowledged that passive
smoking is dangerous, a Philip Morris spokesman said people
should listen to the experts.
"We think that the public should be guided by their public health
officials with regard to risk associated with environmental tobacco
smoke, second-hand smoke," said Billy Abshaw, a spokesman for
Philip Morris.
"We think there are options available to minimize environmental
tobacco smoke in general in ways to find comfort and balance for
nonsmokers and smokers."
JAMA 2001;286:436-441,462-463.
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