HELENA, Mont. (AP) - Dr. Robert Shepard, a longtime proponent of a citywide indoor smoking ban, was skeptical when a colleague suggested research showed heart attacks had dropped sharply during the first two months the law was in effect.
Now, about eight months after Dr. Richard Sargent first noticed the trend, both doctors are saying their data shows heart attacks in Helena fell by more than half last summer after voters passed the ban.
The doctors say that suggests cleaning up the air in bars and restaurants quickly improves health for everyone.
On Tuesday, Sargent presented the pair's study on the Helena law at the annual meeting of the American College of Cardiology in Chicago. It's considered the first study to examine what happens to public health when people stop smoking and breathing secondhand smoke in public places.
"I'm glad that someone finally noticed it. This has probably been going on in every other community with a smoking ban," Shepard said.
Critics of the smoking ban questioned the legitimacy of the findings because the physicians were backers of the ban long before they analyzed results of the study.
Helena's smoking ban was adopted by 62 percent of voters in June and remained in effect until December, when a legal challenge halted enforcement. During that period, the study says, hospital admissions for heart attacks dropped from seven a month to about three.
The statistics also showed a possible spike back to normal levels after the city stopped enforcing the ban.
The study tracked heart attacks in the area during the past four years, and adjusted the figures for seasonal variations. The study also counted visitors who had a meal in the area.
Doctors agreed Tuesday that the small number of heart attacks in Helena, population 26,000, may not indicate large-scale effects of smoking bans. Nevertheless, said Dr. Richard Pasternak, director of preventive cardiology at Massachusetts General Hospital, "It's very plausible that you could see this kind of broad effect."
The study found the smoking ban appeared to have its biggest effect on smokers. Their incidence of heart attacks dropped by three-quarters, compared with two-thirds for former smokers and one-half for nonsmokers.
Some bar and casino owners in Helena criticized the study's findings. Greg Straw, who runs the Montana Nugget Casino, said smokers continued to light up while the ban was in effect - they just stayed at home or went to bars in neighboring towns.
Straw dismissed the idea that the ban was linked to a decline in heart attacks.
"I think that absolutely has nothing to do with the smoking ban," he said.
Laura Fix's family owns Fat Boy and Charlie's, a Helena bar and casino about a mile from the edge of town. Fix said the ban nearly crippled her business, but had little effect on her customers who smoke.
"They just went outside the city limits," she said.
Shepard acknowledges that critics will point to his and Sargent's support for the smoking ban in refuting the study.
"They can say what they like. The bottom line is, the data speaks for itself. We don't have to apologize for our particular bias," Shepard said.
In Chicago, Sargent acknowledged the study's scale should be increased to a community larger than Helena.
"This is a tiny, little community in the middle of nowhere," he said. "This study needs to be replicated in New York City."
A rule that took effect in New York on Sunday bans smoking in city workplaces. Last week, New York passed a statewide smoking ban, joining California and Delaware with stringent rules on indoor smoking. A Florida ban passed by voters last year takes effect in July.
Next month, indoor smoking becomes illegal everywhere in Boston except private homes, hotel rooms and some cigar bars. Dallas also recently banned restaurant smoking, as have a few smaller cities around the country.
