Thursday, October 29, 2009

Observations on a New Tobacco Harm Reduction Commentary

In August I discussed a comprehensive meta-analysis of smokeless tobacco use and cancer, which was published by Peter Lee and Jan Hamling in the prestigious journal BMC Medicine. Recently that journal published a commentary by David Timberlake and Jason Zell, professors at the University of California at Irvine. The article, available here, will be widely read and will likely promote lots of debate, so I will make some critical comments.

Timberlake and Zell attribute the origin of the “controversy” over the use of smokeless tobacco as a “potential substitute for cigarettes” to the “steep decline” in smoking among Swedish men “over the past two decades.” They conclude that “it is premature to state that the increased use of ‘snus’ is causally associated with tobacco substitution and the decline in morbidity.” Unfortunately, Timberlake and Zell have repeated a common misunderstanding of the Swedish data.

Most commentators describe the “Swedish experience” as a recent phenomenon. This is incorrect. Philip Cole and I published a study earlier this year in the Scandinavian Journal of Public Health and discussed in this blog, which examined lung cancer rates among men and women in all European Union countries for the past 50 years. We concluded “that snus use is inversely correlated with cigarette consumption among men in Sweden, resulting in the lowest [lung cancer mortality rates] in Europe for most of the past 50 years.” Thus, Timberlake and Zell are mistaken that it is “premature to state that increased use of ‘snus’ is causally associated with tobacco substitution and the decline in morbidity.” In fact, nothing else adequately explains the profound and sustained differences between very low lung cancer mortality in Swedish men compared with other EU countries over the past half-century.

Timberlake and Zell correctly observe that clinical trials are starting to address the efficacy of tobacco harm reduction. They describe a Danish quit-smoking trial that used smokeless tobacco as successful at 7 weeks and unsuccessful at 6 months, but they could have explained that the investigators urged subjects to be tobacco-free at 3 months. It is perfectly clear that smokeless tobacco will not be any better for smoking cessation than pharmaceutical nicotine (that is, terrible) IF the ultimate objective is complete nicotine and tobacco abstinence. This objective is the Achilles heel of the conventional quit-smoking mindset, and it is entirely unnecessary. The appropriate objective is for smokers to lead longer and healthier lives, and this can be accomplished by not forcing smokers to abstain completely from nicotine and tobacco.

Timberlake and Zell repeat anti-tobacco extremists’ claims that “[c]arcinogens in smokeless tobacco include high levels of nitrosamines, polycyclic aromatic hydrocarbons and other agents,” and they cite a monograph from the zealous International Agency for Research on Cancer. These contaminants are present in smokeless tobacco, but in miniscule concentrations that aren’t relevant to human health.

Trace levels of contaminants are in virtually every product that humans consume. For example, in 2000 Bruce Ames, a well known expert in carcinogenesis (cancer causation), published an article noting that roasted coffee contains thousands of chemical agents. At that time about 30 of them had been tested as carcinogens, and 21 were positive. Thus, even though coffee contains cancer-causing chemicals, there is no epidemiologic evidence that coffee is a significant risk factor for any cancer in humans who consume it. Similarly, although smokeless tobacco contains trace levels of carcinogens, the cancer risks among smokeless users are so low that they are barely measurable with modern epidemiologic methods.

Timerlake and Zell represent that Lee and Hamling observed “excess risk” for oropharyngeal cancer among smokeless tobacco users, but this is perplexing. As I noted in August, Lee and Hamling found no risk related to smokeless tobacco after adjustment for smoking and alcohol, two risk factors acknowledged by Timberlake and Zell.

In some sections Timberlake and Zell get on the anti-industry train, which may be attractive to anti-tobacco extremists but may not be entirely accurate. For example, they suggest that Philip Morris had a crystal ball as early as 1984 regarding the benefits of smokeless tobacco. This is just short of nonsense, because until 2005, none of the major cigarette manufacturers had ANY stake in smokeless tobacco. Prior to that, cigarette and smokeless manufacturers were absolute competitors, representing a lost opportunity for tobacco control advocates who failed to focus on the most harmful products (cigarettes and other combustible tobacco products).

Timberlake and Zell also appear to agree with the anti-industry complaint that it is “more interested in the dual use of tobacco products, rather than tobacco substitution.” It is true that some ads promote smokeless use during “times when you can’t smoke.” But the industry has been forced into a marketing corner so tight that it doesn’t have any other choice. With the idiotic warning present on smokeless products since 1986 (This product is not a safe alternative to cigarettes), a marketing campaign focusing on substitution would be a ticket to self-destruction. It is depressing to think that FDA regulation is likely to make a science-based switch-to-smokeless pitch even less likely.

I have been critical, but there is much to recommend Timberlake and Zell’s commentary. For the most part, they provide a balanced discussion of key issues, which is absent in many other published articles. With respect to the Lee-Hamling study, they correctly conclude that “the overwhelmingly null (i.e., zero) associations with cancer in this high quality analysis are provocative, if not compelling.” Regarding the gateway issue (the idea that smokeless tobacco use leads to smoking, especially among children), their interpretation is on target: “even if a gateway effect to smoking exists, which is doubtful, only a minority of smokeless-tobacco users would be affected.” They address the role of human papillomaviruses, another commonly forgotten risk factor in oral and pharynx cancer. Finally, they recognize that FDA regulation “may not be the sole determinant of harm reduction’s fate in the USA,” and they “anticipate that much of the debate will shift from the discussion of epidemiologic data to the discussion of the marketing, health communication and economics of smokeless tobacco.” When that happens, it will be long overdue.

Friday, October 23, 2009

Nonsense from the American Cancer Society

Last week, the New York City Council voted to ban all flavored tobacco products. While the ban excludes menthol cigarettes, it effectively prohibits many smokeless tobacco products that are vastly safer alternatives to cigarettes. This action means smokers who wish to quit without abstaining from nicotine will have fewer options available. That’s perfectly acceptable to tobacco prohibitionists, who claim that the law will prevent smoking by children, even though adolescent smokers overwhelmingly prefer unflavored cigarettes (see my post on flavored products, here).

On October 16, Jeff Stier, associate director of the American Council on Science and Health, wrote a commentary in the New York Post that was justifiably critical of the ban. Stier observed that smokeless tobacco and e-cigarettes “are noncombustible, eliminating almost all smoking risks. They could be a lifesaver; the only reason to crack down is the ideology of the public-health movement, which has decided that anything that has tobacco in it, or even looks like a cigarette, must be illegal, even for sale to adult smokers trying to stop smoking.” Stier concluded that these types of “government actions will do nothing to protect kids. The only effect is to promote the most dangerous form of tobacco use, smoking cigarettes.” Stier’s comments reflect ACSH’s position as a relentless opponent of smoking, but a strong supporter of tobacco harm reduction.

On October 22, the American Cancer Society responded to Stier with a letter to the Post from Clare Bradley, Chief Medical Officer of the Eastern Division. What Dr. Bradley said was pure nonsense.

Dr. Bradley claims that “using snus does not eliminate the risk of lung cancer. Smokers who use smokeless tobacco as a supplemental source of nicotine in an effort to quit smoking actually increase their risk of lung cancer.” Is it possible that a Cancer Society official actually believes that smokeless tobacco increases the risk for lung cancer?

Dr. Bradley’s prescription for smokers desperate to quit: “The best way to quit smoking is not to start.” She tells smokers who may not be able to accomplish that task that “nicotine-replacement therapy [NRT], when paired with a program to help change behavior, is a proven cessation method.”

What is “proven” about NRT is that it works for only 7% of smokers who try it.

By opposing tobacco harm reduction, the American Cancer Society is working against the health and welfare of smokers.

Monday, October 19, 2009

Misinformation from the American Dental Association

On October 9, the American Dental Association submitted a letter to the Food and Drug Administration in response to a federal register notice requesting public input on the role of the FDA in tobacco regulation. In the letter, available on the website, the ADA uses pseudo-scientific language to advocate for prohibition of all tobacco products, including smokeless tobacco. Following are some of the letter’s most absurd statements.

1. “We also ask that you begin your work by regulating industry assertions that smokeless tobacco is a healthier (or less harmful) alternative to cigarette smoking.”

While the ADA refers to “industry assertions” about the relative safety of various tobacco products, it ignores the growing number of independent health assessments from academia, public health organizations and other non-industry sources. The British Royal College of Physicians, the American Council on Science and Health and the American Association of Public Health Physicians have concluded that smokeless tobacco use is associated with a tiny fraction of the health risks of smoking.

The task of regulating “industry assertions” was intensively covered in the bill granting FDA regulatory control over tobacco. In fact, the agency was empowered to restrict any action that could “be reasonably expected” to result in “consumers believing” that an alternative tobacco product may have some health benefit vis a vis cigarettes. That’s not just regular commercial speech (e.g., advertisements), but ANY speech, and it’s one reason that several tobacco companies are suing in federal court to block this part of the law.

2. “Smokeless tobacco is not a healthy alternative to cigarette smoking; both products pose health risks. Compared with cigarettes, smokeless tobacco products are less likely to cause lung cancer but they are associated with oral (mouth) and pharyngeal (throat) cancers, as well as cancers of the stomach and pancreas (5,6,7,8).”

No one is suggesting that smokeless tobacco is a “healthy” alternative. The ADA is inappropriately manipulating the legitimate message of tobacco harm reduction.

At least the ADA admits that smokeless tobacco is “less likely” to cause lung cancer. In fact, the most comprehensive study of smokeless tobacco and cancer (previously discussed in this blog) revealed NO risk for lung cancer. Apparently, the ADA doesn’t consider the elimination of 125,500 deaths from lung cancer to be a sufficient public health gain to offset what it believes are risks from other cancers. That meta-analysis also proves that the ADA is wrong on the other cancers as well.

Note that three of the four numbered references supporting the ADA’s statements about other cancers were from the 1990s, when many experts mistakenly believed that smokeless products weren’t much safer than cigarettes. Either the ADA only reviewed selective scientific literature prior to 2000, or the organization chose to ignore irrefutable evidence supporting tobacco harm reduction. The fact is: If all U.S. smokers had instead used smokeless tobacco, cancers now attributable to smoking would plummet to around 1% of their current numbers.

3. “Researchers have found that adolescent boys who use smokeless tobacco products are highly likely to become cigarette smokers within four years (14).”

This is the ADA’s major rationale for its allegation that smokeless tobacco is a “gateway” to cigarette smoking. The reference is to a study by Scott Tomar, a staunch opponent of tobacco harm reduction at the University of Florida. Tomar’s theory has been disproven by Kozlowski and colleagues in published articles available here, here and here. These studies carefully examine datasets in order to determine whether ST or cigarettes were used first. They concluded that ST use plays no significant role in smoking initiation. The vast majority of smokers never used ST, and two-thirds of ST users either never smoked, or they smoked prior to using ST. That makes two-thirds of ST users ineligible to even be considered as gateway users.

It is not surprising that boys who use ST are more likely to become smokers, since experimentation with one tobacco product is closely linked to other similar behaviors. But opponents of harm reduction are deliberately confusing association with causation. Smoking among teenagers is also associated with alcohol use, drug use, risky driving, risky sex, bad grades and behavior problems, but it doesn’t cause them.

4. “That is one among many reasons former U.S. Surgeon General Richard H. Carmona classified the smokeless tobacco alternative as a ‘public health myth.’”

I am astounded that the ADA is still quoting the 2003 Congressional testimony of former Surgeon General Richard Carmona; he has virtually no credibility on this topic. I also testified at that hearing, and I was stunned by Carmona’s uneducated and completely inaccurate statements.

In his testimony, Carmona stated: “There is no significant scientific evidence that suggests smokeless tobacco is a safer alternative to cigarettes.” Carmona ignored decades of published research and the prestigious British Royal College of Physicians, who had reported a year earlier that smokeless tobacco products are “on the order of 10 to 1,000 times less hazardous than smoking”.

Carmona also testified that he wanted to ban tobacco products. Asked if he “would support banning or abolishing all tobacco products,” Carmona responded, “I would at this point, yes.” This marked the first time a Surgeon General had called for outright prohibition, and he sent would-be supporters running from the Hill. Even the Campaign for Tobacco-Free Kids, which has shown no interest in helping inveterate adult smokers, couldn’t support Carmona. Its spokesman commented that “We would all like to see a tobacco-free world…we can’t just take away their tobacco.” Bush administration officials responded quickly. “That is not the policy of the administration,” commented White House spokesman Scott McClellan, saying that Carmona’s comments represented only his views as a doctor.

The American Dental Association’s prohibitionist policy towards tobacco use is a disservice to dentists and their smoking patients; it denies them life-saving information about effective and vastly safer smokeless alternatives.

Friday, October 9, 2009

More Good News on Teen Smoking: Rates At or Near Record Lows

Last week I discussed my recently published study of smokeless tobacco use among adult men in the U.S. But what about tobacco use among children? It’s an important question. Earlier this year, when Congress gave the FDA regulatory authority over tobacco products, Chris Dodd (D- CT) told the Senate that the bill was “necessary…to protect our children and the public health from deadly tobacco products.”

Readers already know that smokeless tobacco doesn’t even come close to falling into the “deadly” category. In fact, the health risks (cancer, heart and circulatory disorders and all other tobacco-related illnesses) of long-term smokeless tobacco use are so small that they are barely measurable using modern epidemiologic methods.

Still, American media dwell on references to tobacco use among children, giving the impression that it is an escalating crisis. As Senator Blanche Lincoln (D- AR) put it, the FDA bill “would implement important marketing restrictions on tobacco products and especially on the marketing practices that have been shown to increase tobacco use among our Nation's young people.”

Let’s look at data behind those “increases” in tobacco use.

The title for this post was borrowed from a press release dated December 11, 2008 by Monitoring the Future, an authoritative source for information about tobacco use among children. MTF is a long-term survey-based study of the behaviors, attitudes and values of American high school students. It has been collecting information on smoking and smokeless tobacco use among grade 12 students since 1975. MTF, like other youth surveys, counts any child who has used a tobacco product within the past 30 days as a current user. Prevalence estimates using this definition are not understated; they tend to be higher than those using the adult definition, which counts only people using tobacco “every day or some days.”

Let’s start with 1998, the year of the Master Settlement Agreement, in which seven tobacco companies (including UST, the nation’s largest smokeless manufacturer) agreed to change the way tobacco products were marketed and pay the states an estimated $206 billion. Tobacco manufacturers agreed not to “take any action, directly or indirectly, to target Youth within any Settling State in the advertising, promotion or marketing of Tobacco Products, or take any action the primary purpose of which is to initiate, maintain or increase the incidence of Youth smoking within any Settling State.” We’ll end with 2008, the most recent year for which MTF data is available.

According to MTF, 8.8% of 12th graders were users of smokeless tobacco in the past 30 days (15.6% percent of boys and 1.5% of girls) in 1998. Ten years later, only 6.5% were current users (11.8% of boys and 1.0% of girls), a decline of 26%.

Smoking rates were also declining during this period. In 1998, 35.1% of 12th graders smoked cigarettes (36.3% of boys and 33.3% of girls). By 2008 the prevalence of smoking was 20.4% (21.5% for boys and 19.1% for girls). This means that smoking among high school seniors declined by 42% in the decade after the MSA.

It is informative to compare the 2008 rates of current smoking (20.4%) and smokeless tobacco use (6.5%) with usage rates for two other popular teenage drugs, alcohol and marijuana. A whopping 43% of 12th graders used alcohol, and 28% had been binge drinking; 19.4% of them had used marijuana, almost the same percentage as smoking.

Last year over four out of ten 12th graders reported drinking and two-thirds of drinkers had binged, putting them at immediate and potentially life-threatening risk for alcohol poisoning, motor vehicle and other accidents. In comparison, the cigarette smoking rate was about the same as that for smoking marijuana, and smokeless tobacco use was far lower.

Tobacco use among children is a relatively small problem, and shrinking virtually every year. More importantly, the issue of teen tobacco use is entirely irrelevant to tobacco harm reduction. Society has a genuine interest in stopping tobacco initiation among children. But it is disingenuous for tobacco prohibitionists to label every attempt to provide vastly safer smokeless substitutes to adult inveterate smokers as an attack on children. If prohibitionists have specific evidence that tobacco manufacturers are marketing to children, they should contact the appropriate state attorney general. Many states have an expedited process for policing and enforcing MSA provisions about targeting children. Otherwise, these allegations represent nothing more than hollow and specious diatribes.

Tobacco harm reduction isn’t a children’s issue. The 8 million Americans who will die from a smoking-related illness in the next 20 years are not children. They are adults who are at least 35 years old. Preventing youth access to tobacco is vitally important, but the issue should not be twisted to condemn cigarette-using parents and grandparents to premature death.

Friday, October 2, 2009

Smokeless Tobacco Use Among Men in the U.S., 2000 and 2005

Epidemiologist Philip Cole and I recently completed a study of smokeless tobacco (ST) users in the United States in 2000 and 2005, based on data from National Health Interview Surveys (NHIS), which are also used by the Centers for Disease Control and Prevention to estimate how many Americans smoke. Our manuscript was published in the Journal of Oral Pathology and Medicine.

Overall, we found that the percentage of American men who use ST is a low but stable 4%. Almost all ST users are white, about half are 25-44 years old, and the majority have up to a high school education. Eight out of ten ST users live in the South or the Midwest. Over 50% of ST users lived in small metropolitan and rural areas, while only 2% lived in metro areas with populations of 5+ million.

There was some good news: of the 4.1 million ST users in 2000, 1.1 million were former smokers. Only 120,000 of them had quit smoking by switching to ST; the other 980,000 had used other methods. However, at some point, these former smokers apparently made the decision that they wanted to remain smoke-free without abstaining entirely from nicotine and tobacco, so they became ST users. By 2005, the number of ST users who were former smokers had grown to 1.4 million. 

Although over a million ST users are former smokers, we also found that there were about three million smokers who were former ST users. This is the bad news, because these men have gone from very low risk ST to high risk cigarettes. This reflects the fact that most American smokers are not aware of the large difference in risk between ST use and smoking. For example, a 2003 survey found that while 80% of American smokers were aware of ST products, only 11% correctly believe that they are less hazardous than cigarettes. Another survey found that 82% of American smokers incorrectly believe that chewing tobacco is just as likely to cause cancer as is smoking cigarettes. A 2007 study of adult smokers in Australia, Canada, the UK and the U.S. found that only 13% correctly believed that ST is less hazardous than cigarettes.

In 2005, there were 1.4 million American men who were dual users of both cigarettes and ST products. These men consumed nicotine both from cigarettes and from ST, and the latter clearly resulted in lower consumption of the former. In both 2000 and 2005, every-day smokers who also used ST every day consumed significantly fewer cigarettes on average than exclusive smokers (13 cigarettes per day vs. 20 cigarettes). If these dual users knew that ST products were only 1% as hazardous as cigarettes, it is possible that many would have chosen to use only ST.

Many media reports have noted the sharp increases in sales of moist snuff over recent years. Our study revealed that increased snuff use among men between 2000 and 2005 is due in large part to a decline in the use of chewing tobacco, a long-term trend that has been apparent since the mid 1980s. These changes for chewing tobacco and snuff are in line with a report from the U.S. Department of Agriculture Economic Research Service showing that consumption of chewing tobacco in the U.S. decreased 20% from 49.4 million pounds in 2000, to 39.2 million pounds in 2005. In contrast, moist snuff consumption increased 28% over the same period, from 65.9 million to 84.5 million pounds.

Our study provides important information about American ST users, and it reveals that a large proportion of ST users are concurrent or former smokers. These findings should inform the growing discussion among health and policy experts about how ST can serve as a less hazardous cigarette substitute for inveterate smokers.