Data from Australia Show No Effect of Smoking Bans on Heart Attack Admissions

National data from all hospital admissions in Australia show no apparent effect of smoking bans that were enacted in the various Australian states between 2005 and 2007. The data are easily available online and Christopher Snowdon over at Velvet Glove, Iron Fist has produced graphs of long-term trends in heart attack admissions in Australia before and after these smoking bans. He provides analyses of both the national trend in heart attack admissions and in the state-specific heart attack trends, showing with an arrow the point at which the smoking ban became active in each of the states.

There is no apparent effect of the smoking ban on heart attack admissions in any of the states. The most important pieces of data are those for New South Wales and Victoria, because they contain the largest populations. In both, there was no apparent effect of the smoking ban on heart attacks. If anything, there was an increase in heart attacks associated with the first nine months of implementation of the smoking bans in those states.

As Snowdon notes: "Note that the Helena hypothesis specifically claimed a drop in heart attacks of 40% within the first six months of the ban. Although Victoria and New South Wales introduced their bans towards the end of the time-frame, there was still nine months between July 2007 and March 2008 for a drop in heart attacks to occur. Instead, the rate rose from 51,667 to 55,676 between 2006/07 and 2007/08."

These results are in accordance with the observations of several tobacco researchers in Australia who have previously told me that they failed to see any significant effect of smoking bans there on heart attack trends.

The Rest of the Story

Today's story adds to the list of states and countries for which national or state-specific data show no effect of the smoking ban, bringing the total up to 10. The strength of these data is that the entire country or state is included (there is no sampling), there is little concern about heart attack cases that may have presented to out-of-town hospitals, and the populations involved are quite large, helping to protect against random fluctuations in the data which could present the false appearance of a large increase or decrease in heart attacks from one year to the next.

As Snowdon writes, reflecting a similar sentiment about the importance of these population-based, large studies of national or state-specific data: "It would, however, be nice to think that journalists might ask themselves whether data collected by professional tobacco control advocates from obscure towns really trumps genuine hospital admissions data collected by professional statisticians from entire nations."

The fact that the largest declines in heart attacks in the published studies occurred in the smallest of communities and that data for every state or country studied so far fails to confirm any significant short-term effect of smoking bans on heart attacks argues against the validity of the conclusion reached by the Institute of Medicine (IOM) committee, which failed to examine the readily available heart attack admissions data from any of these 10 states and/or countries.

It is quite clear that the IOM report failed to provide any review of these unpublished data. Nevertheless, the committee claimed that it had comprehensively reviewed the unpublished data: the press release states: "The IOM committee conducted a comprehensive review of published and unpublished data and testimony on the relationship between secondhand smoke and short-term and long-term heart problems."

In my opinion, the premature rush to judgment by anti-smoking researchers and groups on the issue of smoking bans and heart attacks undermines both the scientific integrity and the scientific credibility of the tobacco control movement.

While the conclusions of anti-smoking groups about the smoking ban and heart attack studies is receiving widespread publicity, so is the criticism of these groups' unsupported pronouncements. For example, an op-ed in Sunday's New York Post by Jacob Sullum -- a senior editor of Reason Magazine -- calls the IOM committee out for its sloppy and biased review of the data.

Sullum writes: "a closer look at the IOM report, which was commissioned by the US Centers for Disease Control and Prevention, suggests its conclusions are based on a desire to promote smoking bans rather than a dispassionate examination of the evidence. Thousands of jurisdictions around the world restrict smoking. Some of them are bound to see significant drops in heart attacks purely by chance, while others will see no real change or significant increases. Focusing on the first group proves nothing unless it is noticeably bigger than the other two groups. The largest study of this issue, which used nationwide data instead of looking at cherry-picked communities, concluded that smoking bans in America "are not associated with statistically significant short-term declines in mortality or hospital admissions for myocardial infarction." ... That study, published by the National Bureau of Economic Research in March, suggests that publication bias -- the tendency to report positive findings and ignore negative ones -- explains the "consistent" results highlighted by the IOM committee. But even though the panelists say they tried to compensate for publication bias by looking for relevant data that did not appear in medical journals, they ignored the NBER paper, along with analyses that found no declines in heart attacks following smoking bans in California, Florida, New York, Oregon, England, Wales and Scotland." ...

"when people stop smoking, their heart-attack risk declines gradually over several years, and it's hard to see why the risk would fall any faster for people exposed to secondhand smoke. Furthermore, estimates from the CDC and the American Heart Association indicate that smoking and secondhand smoke together account for about 25 percent of heart-disease deaths. So how could a smoking ban, even one that eliminated all smoking, cut heart attacks by 40 percent (or 47 percent, as another study claimed)? The IOM panelists dodge these issues by declining to estimate the size or the timing of the impact from smoking bans, citing the limitations of the studies and the wide variations between them. But "if you can't even estimate the magnitude of an effect," notes Michael Siegel, a Boston University public-health professor who was one of the report's reviewers, "you are hardly in a position to conclude that [it] exceeds random variation combined with the known secular decline in heart-attack rates." ... Siegel, who faults the IOM committee's "sensationalistic" approach, is a longtime backer of smoking bans who nevertheless tries to separate his political advocacy from his scientific analysis. It's too bad the authors of the IOM report, who immediately used it as an excuse to demand strict smoking regulations throughout the country, did not follow his example."

It pains me to see the scientific integrity of the tobacco control movement imploding like this. While I support the same goal of protecting the public from secondhand smoke exposure (though not the agenda of spreading smoking bans to the wide-open outdoors), I think the scientific credibility of public health groups is our most prized possession. To squander that in an attempt to promote even a valuable public health policy is foolish. But more importantly, misrepresenting the scientific evidence to the public is, I believe, unethical. It is inconsistent with the ethical code of conduct of public health.