By Genevra Pittman
Reuters

Heart attacks dropped by one-third in one county in Minnesota after two smoke-free workplace ordinances went into place, a new study shows.

The lead researcher on the work said that decline was likely due to less secondhand smoke exposure in restaurants and bars, as smoke can trigger heart problems due to its effects on arteries and blood clotting.

But another tobacco expert questioned whether the drop in heart attacks could be clearly attributed to the two ordinances, which banned smoking in restaurants starting in 2002 and then in all workplaces, including bars, in 2007.

Researchers from the Mayo Clinic in Rochester, Minnesota found that in the 18 months before the first ordinance was enacted, the rate of heart attacks in Olmsted County was 151 for every 100,000 people. By the 18 months following the second ordinance, that fell to 101 per 100,000 people.

Dr. Richard Hurt said a few other studies, including one from Montana, have also suggested smoke-free workplace laws could impact heart attack rates.

But, he told Reuters Health, "There have been lingering doubts among some people about whether or not this was a real finding. We think we have produced the most definitive results that anyone can produce related to smoke-free laws and heart attacks."

Hurt, who led the research, said other predictors of heart attacks - including cholesterol levels, blood pressure and diabetes and obesity rates - all held steady or increased in Olmsted County over the study period.

"The only thing that really changed here was the smoke-free workplace laws," he said.

About 3,600 municipalities have laws on the books that restrict where people may smoke, according to the American Nonsmokers Rights Foundation, with more than 1,000 including a smoke-free provision of some kind.

According to Hurt, the findings also make sense biologically. Exposure to secondhand smoke can cause immediate changes in the lining of the aorta, and can make blood platelets stickier - so they're more likely to form a dangerous clot.

The study is in line with the Institute of Medicine, which advises the U.S. government and said in a 2009 statement that, "data consistently demonstrates that secondhand-smoke exposure increases the risk of coronary heart disease and heart attacks and that smoking bans reduce this risk."

Hurt's results are published in the Archives of Internal Medicine.

He and his colleagues tried to account for general changes in heart attack rates that might have happened regardless of smoke-free laws. They found heart attacks had been declining even in the years before the ordinances - but fell much faster once they were put in place.

But that analysis wasn't convincing enough for Dr. Michael Siegel, a tobacco control researcher from the Boston University School of Public Health.

"The main problem with this study is that there's no control group or comparison group. This is a look only at what happened before and after an ordinance went into effect in one particular county," Siegel, who wasn't involved in the research, told Reuters Health.

"We have no idea whether heart attacks may also have gone down in other counties in Minnesota that didn't have this smoke-free law. Without knowing that, I don't see how you can make the conclusion that this (decline) was due to the law."

Siegel said there is more-convincing evidence that smoke-free workplace laws can help protect against asthma attacks and other lung problems.

"We don't need to prove that they actually decrease heart attacks over a short period of time," he said. "There's lots of reasons to support (these laws)."

People who live in apartment buildings, especially those with children, breathe in tobacco smoke even if no one in their own household smokes, a new study shows.

Researchers found that about one third of study participants living in apartment buildings, condominiums and other multi-unit housing reported smelling smoke in their buildings, and about half of those residents reported smelling smoke in their own units. People were only eligible to participate in the study if no members of their household smoked in the home.

The findings also showed that 41 percent of people with children reported smelling smoke in their building, whereas 26 percent of people with no children said the same.

That may be because people with children, on average, are poorer than people without children, so they tend to live in buildings with larger numbers of other people who are smoking, said study researcher Dr. Jonathan Winickoff, an associate professor in pediatrics at MassGeneral Hospital for Children in Boston. There is a general association between being poorer and smoking, he said.

But taken together with another recent study, the findings mean that half of parents whose children are exposed to tobacco smoke don't know it, Winickoff said. In that earlier study, Winickoff and his colleagues found that nine out of 10 children living in apartments had a chemical called cotinine in their blood. Cotinine is an indicator that a person has breathed in tobacco smoke.

"We know that if you smell it, you child will have evidence of tobacco smoke exposure in their blood. But just because you don't smell it, doesn't mean you're not exposed," Winickoff said.

Exposure to secondhand tobacco smoke has been linked with higher rates of asthma, pneumonia and ear infections in children, even when researchers take into account other factors linked to these conditions, such as poverty and race, he said.

Some policy makers are making efforts that could improve the health of children living in apartment buildings, Winickoff said. Public housing authorities in Maine and in Boston, for example, will soon implement mandates that buildings become smoke-free, and in New York City, Mayor Michael Bloomberg is advocating for disclosure rules, which would require all multi-unit buildings to clearly state whether smoking is permitted in the building.

"People will have a choice to live in a building that has clean air, and I think we want people to have choices," Winickoff said.

The next step in his research, Winickoff said, is to look at how best to raise awareness among people living in multi-unit housing of the impact of allowing smoking in buildings.

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