Some groundbreaking research out of the Mayo Clinic shows that when cities and counties ban smoking in public buildings, the rate of heart attacks in the area drops dramatically.

Researchers mined the data from tens of thousands of medical records from every hospital and medical clinic in Olmsted County, and the findings are eye-opening.

In the 18 months before the county banned smoking in restaurants in 2002, there were 212 heart attacks per 100,000 residents. In 2007, the comprehensive smoking ban was put in place, and heart attacks dropped to 102 per 100,000 residents in the 18 months after the ban began. That marks a 45 percent decline.

"We were quite surprised," said Dr. Richard Hurt. "We thought we'd see a reduction, but until now, the highest reported reduction in heart attacks was 47 percent but most were around 17 percent or so."

Furthermore, when the smoking bans began, the number of sudden deaths from heart attacks dropped from 152 per 100,000 to 76, which is a 50 percent drop.

Hurt said the research forms one of the most definitive links yet between second-hand smoke and heart disease.

"We've known about the relation between heart attacks and reduction of heart attacks in smoke-free work places, but this really nails it down," said Hurt.

The research also shows that after the smoking ordinance took effect in Olmsted County, the number of adults who smoked dropped by 23 percent.

Now, Hurt says the researchers plan to recommend that second-hand smoke be considered the sixth risk factor for heart disease and that people should avoid it.

"People with known coronary disease should have zero -- no exposure -- to second-hand smoke because the risk is too high," said Hurt.

The current risk factors are as follows:

   Smoking
   Genetics
   Cholesterol
   Diabetes
   Hypertension

For more stories from KMSP in Minneapolis go to myfoxtwincities.com.

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