Wednesday, June 28, 2006

Surgeon General's Communications Misrepresent Findings of Report; Tobacco Control Practitioners Appear Unable to Accurately Portray the Science

Apparently, the actual conclusions of a comprehensive 727-page report which documents all kinds of adverse health effects of secondhand smoke were not sensational enough for the Surgeon General's office. In what seems to be a contagious phenomenon which has now infiltrated a federal tobacco control organization, public health groups that report the science of secondhand smoke do not seem able to accurately report the science to the public.

Rather than sticking to the carefully-reviewed science in the detailed and thorough report, the press release and other related communications of the Surgeon General regarding the findings of his report were sensationalized in a way that makes these communications quite misleading.

The report documents an increased risk of heart disease and lung cancer among nonsmokers who are chronically exposed to high levels of secondhand smoke. However, instead of simply reporting that finding to the public, the Surgeon General distorted the science to communicate to the public that brief exposure to secondhand smoke can increase heart disease and cancer risk.

Here is what the Surgeon General's report concluded regarding the effects of secondhand smoke exposure on heart disease and lung cancer:

"The evidence is sufficient to infer a causal relationship between secondhand smoke exposure and lung cancer among lifetime nonsmokers. ... The pooled evidence indicates a 20 to 30 percent increase in the risk of lung cancer from secondhand smoke exposure associated with living with a smoker. ... The evidence is sufficient to infer a causal relationship between exposure to secondhand smoke and increased risks of coronary heart disease morbidity and mortality among both men and women."

Here is what the Surgeon General's press release stated:

"Even brief exposure to secondhand smoke has immediate adverse effects on the cardiovascular system and increases risk for heart disease and lung cancer, the report says."

And here is what the Surgeon General stated in his remarks to the media:

"Breathing secondhand smoke for even a short time can damage cells and set the cancer process in motion. Brief exposure can have immediate harmful effects on blood and blood vessels, potentially increasing the risk of a heart attack."

Here is what the Surgeon General stated in an accompanying fact sheet:

"Breathing secondhand smoke for even a short time can have immediate adverse effects on the cardiovascular system, interfering with the normal functioning of the heart, blood, and vascular systems in ways that increase the risk of heart attack."

And here is what the Surgeon General says in an accompanying brochure:

"Even a short time in a smoky room causes your blood platelets to stick together. Secondhand smoke also damages the lining of your blood vessels. In your heart, these bad changes can cause a deadly heart attack."

The Rest of the Story

The rest of the story is that the Surgeon General's press release distorts the science presented in the report and ends up presenting misleading and inaccurate information to the public.

The press release claims that a significant finding of the Surgeon General's report is that: "Even brief exposure to secondhand smoke has immediate adverse effects on the cardiovascular system and increases risk for heart disease and lung cancer."

To re-phrase this for clarity, the Surgeon General is publicly claiming that brief exposure to secondhand smoke increases risk for heart disease and lung cancer.

But there is absolutely no evidence to support this claim. Certainly, no evidence is presented in the Surgeon General's report to support this claim. And certainly, the Surgeon General's report draws no such conclusion.

In fact, such a conclusion flies in the face of common medical sense. How could it possibly be that a brief exposure to secondhand smoke can cause heart disease? It takes many years for heart disease to develop. It takes years of exposure to tobacco smoke even for a smoker to develop heart disease. I estimate that it takes at least 25 years of exposure (based on the fact that very few smokers are diagnosed with heart disease before age 40).

So how could it possibly be that for an active smoker, heart disease takes 25 years of exposure to tobacco smoke to develop, but for a passive smoker, it only takes a single, transient, brief exposure?

It is also quite misleading to tell the public that a brief exposure to secondhand smoke increases the risk of lung cancer. There is certainly no evidence for this and the Surgeon General's report itself draws no such conclusion. In fact, the report makes it clear that most of the studies linking secondhand smoke and lung cancer studied nonsmokers with many years of intense exposure.

The other claims made by the Surgeon General are also quite misleading, although perhaps not as absurdly inaccurate.

"Breathing secondhand smoke for even a short time can damage cells and set the cancer process in motion. Brief exposure can have immediate harmful effects on blood and blood vessels, potentially increasing the risk of a heart attack."


This statement is misleading because it implies that a brief exposure to secondhand smoke can cause cancer (by setting the cancer process in motion). There is simply no evidence to support such a claim, and no such evidence is presented in the Surgeon General's report. More importantly, there is no evidence that brief exposure increases the risk of a heart attack and the Surgeon General's report offers no evidence to this effect, nor does it conclude that brief secondhand smoke exposure does increase heart attack risk. This is pure speculation, unsupported by any compelling scientific evidence.

"Breathing secondhand smoke for even a short time can have immediate adverse effects on the cardiovascular system, interfering with the normal functioning of the heart, blood, and vascular systems in ways that increase the risk of heart attack."

Again, while there certainly is evidence presented in the report that brief secondhand smoke exposure interferes with the "normal" functioning of the heart, blood, and vascular systems, there is no evidence that these changes acutely increase the risk of a heart attack. Moreover, even if one relied on pure speculation, rather than on science, one would have to clarify one's claim by specifying that it only referred to individuals with pre-existing severe coronary artery disease, something which the Surgeon General does not do here.

"Even a short time in a smoky room causes your blood platelets to stick together. Secondhand smoke also damages the lining of your blood vessels. In your heart, these bad changes can cause a deadly heart attack."

Once again, this is pure speculation, not based on any scientific evidence. There is no conclusion in the Surgeon General's report that brief exposure to secondhand smoke causes fatal heart attacks, as claimed here. There is no evidence presented in the report which documents any increased fatal heart attack risk associated with a brief exposure to secondhand smoke. And even pure speculation would require one to clarify this claim to refer only to individuals with severe existing coronary artery disease.

I need to make it clear that none of these misleading and inaccurate scientific claims are made in the Surgeon General's report. What appears to be going on here is very similar to the "20-minute" and "30-minute" claims about which I have written extensively: the science is simply being distorted to sensationalize the findings, resulting in assertions that are misleading, inaccurate, absurd, unsupported by scientific evidence, and inconsistent with the findings of the report itself.

It appears to me that tobacco control organizations of all kinds and at every level are simply unable to accurately and honestly communicate the science of secondhand smoke to the public. For some reason, there appears to be a need to distort the science in an effort to sensationalize it and increase the emotional impact of the communication. The end result is to produce public claims that are inaccurate and which mislead the public.

Now I hope that readers can see why I wrote, even before this report and its accompanying materials were released, that the report would not matter. It turns out that I was correct. It really didn't matter. Apparently, the Surgeon General was going to say whatever he wanted about the acute health effects of secondhand smoke and not let the actual conclusions of the report get in the way.

It didn't matter that the report failed to conclude that there was any heart attack risk associated with brief exposure to secondhand smoke. The conclusion, widely disseminated to the public, was that a brief exposure to secondhand smoke increases heart disease risk and causes heart attacks.

The 727-page document was not necessary to make that claim. More than 80 anti-smoking groups were already making this fallacious claim and since it was and remains unsupported by scientific evidence, it really didn't matter that the comprehensive review of the scientific evidence did not support such a conclusion. The science was simply not going to get in the way of the tobacco control movement's ability to disseminate this sensationalized (and untruthful) claim.

It is important to understand that while the Surgeon General's report itself underwent rigorous scientific review, and thus does not make any outlandish claims, the communications put out by the Surgeon General reporting the findings of the report did not undergo independent scientific review. And it really shows. The difference between the press release and related communications and the Surgeon General's report itself are striking.

In fact, after reading the press release, I was fully expecting to find in the report some conclusions and supporting documentation related to an acute heart attack risk and increased lung cancer risk associated with brief secondhand smoke exposure. I was shocked to find that there was no mention of such a relationship; no conclusions, no documentation. Instead, the report appropriately presented the scientific evidence of acute effects of secondhand smoke on vascular function as supporting the biologic plausibility of the observed effects of chronic exposure on heart disease. There was no suggestion in the report that a brief exposure does or even could increase heart disease risk. Nor was there any suggestion (much less scientific evidence) that a brief exposure is enough to cause lung cancer.

Unfortunately, I'm forced to reach the conclusion that tobacco control organizations are simply unable to accurately communicate secondhand smoke science to the public. They are widely distorting the science to create a more sensational and emotional impact on the public. When this phenomenon goes all the way up to the level of the Surgeon General's office, you know you've got a serious scientific integrity problem.

What has gone wrong?

I worked for two years at the Centers for Disease Control and Prevention, in the Office on Smoking and Health, which is the office that usually leads the review of the Surgeon General's report. So I'm quite familiar with the level of scrutiny that is usually applied to any communications by the Surgeon General, but especially with regards to what is viewed as the rather "controversial" issue of secondhand smoke.

We remained highly vigilant and very careful about our public communications about the effects of tobacco smoke and those of the Department of Health and Human Services, because there was a huge perceived tobacco industry presence that would scrutinize our claims and call us to task if there were any inaccuracies, even if they were slight and not particularly meaningful.

But now, with the tobacco companies having largely abandoned this "oversight" role and playing a back-seat role (their main comment on the report was something to the effect of "We haven't fully reviewed it yet"), there is apparently nothing to stop us from making just about any claims that we want to make.

So if we want to impress the public with the magnitude of the secondhand smoke hazard by trying to convince them that even a brief exposure can cause heart disease and lung cancer, so be it. The tobacco industry is not going to get in our way any more. Why should the science?


NOTE: Since a large number of readers of this post are likely not to be regular readers of this blog, I want to make it clear that I agree with most of the conclusions of the Surgeon General's report itself and that I certainly (and have for many years) believed that chronic secondhand smoke exposure is a cause of heart disease and lung cancer. I believe that the conclusions of the Surgeon General's report are sufficient to justify smoke-free workplace laws. But I think that the truth is enough. I don't see why we need to distort and sensationalize the science in order to increase the impact of these findings and attempt to advance the agenda. In my view, it greatly harms public health by threatening the very credibility of tobacco control and public health practitioners and organizations. In the long run, this is going to harm the public health cause more than any fleeting publicity gains to be obtained from trying to convince people that breathing drifting tobacco smoke for a half hour is going to cause you to have a heart attack, develop atherosclerosis, or come down with lung cancer 30 years later.

No comments:

Post a Comment