2009-01-02 10:33:51
By MIKE STOBBE, AP Medical Writer Mike Stobbe, Ap Medical Writer Wed Dec 31,
6:06 pm ET
ATLANTA A smoking ban in one Colorado city led to a dramatic drop in heart
attack hospitalizations within three years, a sign of just how serious a health
threat secondhand smoke is, government researchers said Wednesday. The study,
the longest-running of its kind, showed the rate of hospitalized cases dropped
41 percent in the three years after the ban of workplace smoking in Pueblo,
Colo., took effect. There was no such drop in two neighboring areas, and
researchers believe it's a clear sign the ban was responsible.
The study suggests that secondhand smoke may be a terrible and under-recognized
cause of heart attack deaths in this country, said one of its authors, Terry
Pechacek of the U.S. Centers for Disease Control and Prevention.
At least eight earlier studies have linked smoking bans to decreased heart
attacks, but none ran as long as three years. The new study looked at heart
attack hospitalizations for three years following the July 1, 2003 enactment of
Pueblo's ban, and found declines as great or greater than those in earlier
research.
"This study is very dramatic," said Dr. Michael Thun, a researcher with the
American Cancer Society.
"This is now the ninth study, so it is clear that smoke-free laws are one of
the most effective and cost-effective to reduce heart attacks," said Thun, who
was not involved in the CDC study released Thursday.
Smoking bans are designed not only to cut smoking rates but also to reduce
secondhand tobacco smoke. It is a widely recognized cause of lung cancer, but
its effect on heart disease can be more immediate. It not only damages the
lining of blood vessels, but also increases the kind of blood clotting that
leads to heart attacks. Reducing exposure to smoke can quickly cut the risk of
clotting, some experts said.
"You remove the final one or two links in the chain" of events leading to a
heart attack, Thun said.
Secondhand smoke causes an estimated 46,000 heart disease deaths and about
3,000 lung cancer deaths among nonsmokers each year, according to statistics
cited by the CDC.
In the new study, researchers reviewed hospital admissions for heart attacks in
Pueblo. Patients were classified by ZIP codes. They then looked at the same
data for two nearby areas that did not have bans the area of Pueblo County
outside the city and for El Paso County.
In Pueblo, the rate of heart attacks dropped from 257 per 100,000 people before
the ban to 152 per 100,000 in the three years afterward. There were no
significant changes in the two other areas.
"The need for protection from secondhand smoke in all workplaces and public
places has never been clearer," said Matthew Myers of the Campaign for
Tobacco-Free Kids, in a prepared statement. He is president of the Washington,
D.C.-based advocacy organization.
But the study had limitations: It assumed declines in the amount of secondhand
smoke in Pueblo buildings after the ban, but did not try to measure that. The
researchers also did not sort out which heart attack patients were smokers and
which were not, so it's unclear how much of the decline can be attributed to
reduced secondhand smoke.
One academic argued there's not enough evidence to conclude the smoking ban was
the cause of Pueblo's heart attack decline.
The decline could have had more to do with a general decline in smoking in
Pueblo County, from about 26 percent in 2002-2003 to less than 21 percent in
2004-2005. If there were stepped-up efforts to treat or prevent heart disease
in the Pueblo area, that too could have played a role, said Dr. Michael Siegel,
a professor of social and behavioral sciences at the Boston University School
of Public Health.
"I don't think it's as clear as they're making it out to be," Siegel said.