Dong-Chul Seo, an assistant professor in IU Department of Applied Health Science, led the study. The results have been published in the latest Journal of Drug Education.
"Heart attack admissions for smokers saw no similar decline during the study, so the benefits of the ban appear to come more from the reduced exposure to second-hand smoke among non-smokers than from reduced consumption of tobacco among smokers," Seo said.
The study was the first to examine the effect of public smoking bans on heart attacks in non-smokers.
If a person is exposed to second-hand smoking for just 30 minutes, it increases the risk for heart attack, even if they have no risk factors.
"What concerns us is the fact that about half of all non-smoking Americans are regularly exposed to second-hand smoke, even though more than 500 municipalities nationwide have adopted some form of a smoking ban in public places," Seo said.
For the study, researchers examined hospital admissions for acute myocardial infarction (AMI) in Monroe County, Ind., and Delaware County, Ind., which are comparable in a number of ways, including population, presence of a college community, median income, racial/ethnic diversity and heart disease death rates.
The study compared the two counties in addition to analysing the 35,482 hospital admissions in Monroe county 22 months before and 22 months after the initial smoking ban was adopted.
In Monroe County, it was found that there was a 70 percent drop in the number of hospital admissions for AMI among non-smoking patients with no history of heart disease, compared to an 11 percent drop in Delaware County.
This translates into a 59 percent net decrease in the number of non-smoking patient admissions for heart attacks after the Monroe County public smoking ban was enforced.