(McClatchy-Tribune Information Services) -- Pushing smokers outside drives down hospitalizations for heart attacks by about 17 percent in the first year and 36 percent after three years, according to an analysis of 13 studies looking at heart-attack rates after indoor-smoking bans.

The analysis strengthens the studies' individual findings, said co-author James M. Lightwood.

It also bolsters support for government-mandated elimination of smoking in bars, restaurants and other public venues, said a trio of Australian researchers whose editorial accompanied the research in the new issue of Circulation: Journal of the American Heart Association.

Acknowledging some limitations with the research, they wrote that "clinicians should advise their patients to avoid public places that permit smoking, and families should be counseled not to smoke at home or in a vehicle with patients."

The study was paid for by the National Cancer Institute.

"Basically, what happens is you have a relatively quick decline in the community rate of heart attack," said Lightwood, an assistant adjunct professor in the department of clinical pharmacy at the University of California, San Francisco.

Lightwood said the study strengthens existing research showing the heart risks from secondhand smoke.

No studies of Ohio heart-attack rates have been published since the ban was enacted statewide, but one study in the analysis was conducted in Bowling Green.

Ohio's statewide ban started in May 2007 and is being challenged in court by a Columbus bar owner who claims it is unconstitutional. Richard Allen, who owns Zeno's Victorian Village, filed the countersuit in Franklin County Common Pleas Court after Attorney General Richard Cordray sued him for unpaid fines for repeatedly violating the ban.

It's notoriously difficult to study a health program's effects on the population, but the fact that multiple studies found similar reductions in heart-attack rates adds credence to the correlation between smoking bans and better health, said Dr. Doug Teske, a pediatric cardiologist at Nationwide Children's Hospital in Columbus.

The findings aren't surprising to Teske, who has long pushed to eliminate smoking in public places.

The study has limitations because of its design: It is an analysis of multiple observational studies, not a controlled randomized study comparing health outcomes in an area with a smoking ban to an area without a ban.

The researchers could not differentiate between a reduction in disease attributed to people who quit smoking after bans and to fewer heart attacks based on less exposure to secondhand smoke, Lightwood said. Study authors identified many outcome-affecting variables that would be good to measure and analyze, he said.

For example, a high rate of smoking inside homes would affect a community's overall exposure to secondhand smoke and might have an effect on overall measures of community health, including the heart-attack rate.

The analysis covered 13 studies of heart-attack rates after indoor-smoking bans.

Copyright (C) 2009, The Columbus Dispatch, Ohio