VOA标准英语2009年-Less Tobacco Smoke Means Fewer Heart Attac（在线收听）

By Carol Pearson
Washington
22 October 2009
 
According to the WHO, smoke kills one person every six seconds
Tobacco deaths rarely make headlines, but the World Health Organization says tobacco smoke kills one person every six seconds. Studies have shown that tobacco smoke is not just deadly for tobacco users. Those who breathe in smoke from other people's cigarettes also have an increased risk for heart attacks. A new study shows that smoking bans have significant health benefits for everyone.

Virginia is the latest U.S. state to ban smoking in restaurants and bars. As communities across the country ban smoking in public places, fewer people are dying from heart attacks.

A study earlier this year in Pueblo, Colorado by the Centers for Disease Control showed heart attacks dropped by 40 percent after a law was enacted to ban smoking at work or in public spaces. New research now supports this and similar studies.

Dr. Neil Benowitz is one of the researchers on this latest report. "If you expose someone to second hand smoke, within minutes you see blood platelets and blood clotting increasing," he explains. "We see that the function of the blood vessels is impaired."

 
Study finds that the smoking bans - reduce heart attacks
And that is when heart attacks can occur. Dr. Lynn Goldman is the report's principal author. "We did conclude a cause and effect relationship between heart disease generally and second hand smoke exposure," she says.

"Even a small amount of exposure of second hand smoke can increase blood clotting, can constrict blood vessels and can cause a heart attack," adds Dr. Benowitz.

The researchers examined data from 11 studies in various countries. They found that smoking bans reduced heart attacks by anywhere from six percent to nearly 50 percent.

"One of the things to understand and appreciate about these smoking bans is that they are all slightly different. Some are enforced consistently, others are not enforced consistently," Dr. Goldman explains. "But despite that, they all show a consistent reduction in acute myocardial infractions and heart attacks after the bans."

Critics say the study is skewed because people who already had heart disease were not screened out. But the researchers say that would have been impossible.

"Most people who are diagnosed with heart disease have their diagnosis when they have their first heart attack," Dr. Benowitz says.

The study was released by the Institute of Medicine, an advisory group for the U.S. government.

As for the Pueblo, Colorado study, 400 people suffered heart attacks before the ban went into effect. In the 18 months after the ban, fewer than 240 people had heart attacks.

Neighboring areas without smoking laws had no change in their heart attack rates.