First, an apology is in order for taking so long to respond to the online discussion surrounding the review by Foulds et al. [1] and the opinion piece by Bates et al. [2]. As we had promised in our earlier reply to Foulds et al. (19 December 2003) and have been reminded by Bates, we are belatedly responding to the specific points raised by Foulds et al. in their e-letter dated 5 December 2003:
First, an apology is in order for taking so long to respond to the online discussion surrounding the review by Foulds et al. [1] and the opinion piece by Bates et al. [2]. As we had promised in our earlier reply to Foulds et al. (19 December 2003) and have been reminded by Bates, we are belatedly responding to the specific points raised by Foulds et al. in their e-letter dated 5 December 2003:
1. “Misrepresentation of our review.” Our commentary did not misrepresent the conclusions reached by Foulds et al. [1]. We cited their direct quote that snus had “...a direct effect on the changes in male smoking and health” and made the observation that their review added little additional evidence to support that conclusion beyond the spotty evidence cited by Bates et al. (and those two papers had several co-authors in common). Yes, we read their 11 journal pages, 8 figures, 2 table, and 66 references, as well as the 8 journal pages Tobacco Control generously devoted to Bates et al. [2]. No one in the mainstream scientific community questions the underlying premise that exclusive use of snus conveys lower risks for death and disease than does exclusive cigarette smoking. The primary question is whether snus was responsible for the decline in smoking in Sweden and related disease patterns. In support of that hypothesis, Foulds et al. cite sales data from Swedish Match, trend data for tobacco use among men and women age 18–70 years that was unadjusted for age, and cross-sectional data from two northern Swedish counties. That evidence for the role of snus in improving public health does, in fact, provide little additional evidence to what was cited by Bates et al. Foulds et al. make much of the sex differences in use of tobacco products in Sweden to support their hypothesis, yet their reliance on crude (unadjusted) patterns actually masks recent trends in tobacco usage in Sweden and undermines their conclusions. In reality, true age-adjusted smoking initiation rates and cessation rates for males and females in Sweden are essentially equal [3].
2. “Selective reporting of findings”. Foulds et al. acknowledge that they omitted several studies because they were from a part of the country where snus usage was low, claiming that “(b)asing conclusions about snus use in Sweden on a study based exclusively in Malmo is like basing conclusions on smoking and smokeless use in the USA on studies in Utah.” Fair enough, although Foulds et al. had fewer concerns with drawing conclusions about the role of snus in Sweden as a whole based on patterns in northern Sweden.
We stand corrected on our statement that “between 1981 and 2001 daily smoking declined more rapidly for 15-16 year old girls (23% to 16%) than boys (13% to 10%), snus use remained rare among girls, and the sex difference in smoking prevalence decreased.” As the figure presented by Foulds et al. in their electronic letter indicates, the rate of decline in smoking among 15–16-year-olds was about the same for boys and girls. However, that pattern, coupled with a high and increasing level of snus usage among adolescent males in Sweden and very low levels of usage among adolescent girls, provides little support for the conclusion reached by Ramstrom and Foulds [4], two of the authors of the 2003 review paper, that use of snus in Sweden is “associated with a reduced risk of becoming a daily smoker.” If that were truly a causal association, we would expect the initiation rate to be declining more rapidly among boys than among girls due to the much greater growth is snus usage among boys, but it is not. Although there was a 10-fold difference in snus usage between 15–16 year-old boys and girls (20% vs. 2%), smoking initiation exhibited a rather constant and much more modest 3–6 percentage point difference during that time period.
Foulds et al. did not respond in their e-letter to broader national trends in Sweden for young males and females that we mentioned in our commentary. We present here more recent data for 16–24-year-olds in Sweden, the age range during which nearly all smoking initiation occurs [3]:
Figure 1. Trends in proportion of persons age 16–24 who used snuff daily or currently smoked (daily or occasionally), by sex. Sweden, 1988–1989 to 2004–2005. Data from Statistics Sweden ULF Surveys.
Secular trends in tobacco use among adolescents and young adults in Sweden (or Norway and the United States, for that matter) do not support a preventive effect of smokeless tobacco use for cigarette smoking. Official national data from Statistics Sweden indicate that daily snuff use among 16-24 year-olds has increased over the past 15 years, from 23.0% in 1988–1989 to 26.5% in 2005 among males and from 0.6% to 3.9% among females (Figure 1). Current smoking (i.e., daily or occasional) in that age group exhibited a flat trend line for males during that time period and a declining trend line for females over the same time period. In 2004–2005, 33.4% of males and 30.2% of females aged 16–24 years in Sweden were current smokers. However, the prevalence of daily smoking was lower for males (9.3%) than for females (13.3%) in that age group. The secular patterns in tobacco use among Swedes aged 16–24 years suggest that snuff may have served as a partial substitute for smoking among males, but had a negligible effect, if any, on smoking initiation rates for either sex.
3. “Tomar et al’s errors in critical appraisal of health effects of snus”. We stand by the original comments regarding the interpretation of the studies by Lewin et al. [5] and Schildt et al. [6]. In the study by Lewin et al., there was an elevated risk for head and neck cancers among an important subgroup (lifetime non-smokers); Foulds et al. only cite the non-significant multivariate relative risk estimate, ignoring that subgroup analysis or the obvious colinearity that occurs in multivariate modeling when nearly all snus users also have a history of smoking. [Since that time that study was published, its lead author, Freddi Lewin, has gone on to a career with Swedish Match]. In contrast, Foulds et al. chose to report only the univariate analyses in Schildt et al., when the multivariate analysis found that neither smoking, alcohol consumption, nor snus were associated with oral cancer. We may be “out on a limb” regarding the carcinogenicity of snus, but we appeared to be joined on that limb by the International Agency for Research on Cancer [7] and the European Commission’s Scientific Committee on Emerging and Newly Identified Health Risks [8].
4. “Birth-cohort patterns relating smoking and snus use.” The birth cohort data presented by Foulds et al. do not support a role for snus in smoking cessation or refute our contention that most snus uptake occurred among young people because they present no data on snus usage. All birth cohorts of men and women experienced declines in daily smoking during that 17-year period; for most birth cohorts the difference between men and women was 2–7 percentage points. Differences were larger for older adults (8–11 percentage points), but women aged 50 years and older began the cohort study with much lower prevalence of smoking. Non-daily smoking remains unreported, even though it accounts for a large proportion of current smoking in Sweden. Most smoking cessation trials would not consider reduction from daily smoking to less than daily smoking as cessation, but perhaps the authors’ clinics and trials use different criteria. The primary point is that evidence such as Figure 1 in the review by Foulds et al., which presents trend data from Swedish Match on consumption of snus and cigarettes, or the cohort data on smoking they posted in their e-letter cannot determine whether the groups taking up snus are necessarily the same ones driving the decline in cigarette consumption; we continue to contend that they largely are not.
5. “Is the sex difference in smoking prevalence due to fewer women in the smoke-free workplace?” We acknowledge that our hypothesis was speculative and lacked direct supporting evidence. However, in their e-letter, Foulds et al. stated: “One thing that doesn’t seem to fit with that is the data on the older age groups presented in the table above. Those aged 50+ in 1980–1 in that (sic) data would mostly have retired from the workforce by 1996–7 and so might be less affected by workplace smoking bans. However, despite that, the sex-difference in cessation is actually stronger in that age group than any other.” That conclusion is not necessarily true; the prevalence of smoking was substantially higher among men age 50 or older than among same-aged women, men were more likely than women to be lost to follow-up by the end of the study, and a greater proportion of men (9.2%) than women (6.2%) died between the second interview and the time of the third follow-up interview [9]. Some of that “sex-difference in cessation” was very likely to have been differential mortality between older men and women, driven heavily by higher smoking-attributable mortality rates among older men. One sure way to quit smoking is to die.
6. “Use of snus as a smoking cessation aid”. Foulds et al. claim that we tried to “brush this important piece of evidence (of snus as a smoking cessation aid) under the carpet.” In fact, in our commentary we stated, “…the large majority of men (71%) and women (97%) who quit smoking did not use snus at their last quit attempt, with modest effectiveness for snus as a cessation strategy in that observational study. That is hardly compelling evidence for snus as "an important explanation" for the decline in smoking in Sweden.” We did not claim that no smokers in Sweden quit smoking by using snus, but we do maintain that the role of snus in reducing smoking has been substantially overstated. When half of the adult population (women) has never used a purported smoking cessation method but still achieved a greater prevalence of complete smoking cessation than the half that has widely adopted that method, it suggests that there are other, more important factors that explain the decline in smoking in Sweden.
7. “This is about Sweden, not the USA.” While that may be true, USA remains the world’s largest market for commercial moist snuff products and reviews such as those by Foulds et al. and an opinion piece such as that of Bates et al. can have significant effects on U.S. tobacco policy, its tobacco industry, and the usage of tobacco products. A great deal has happened since those papers were published six years ago. Nearly the entire moist snuff market in the USA is now controlled by cigarette manufacturers, who are developing and test-marketing new smokeless tobacco products at a furious pace. New products include Marlboro Snus, Camel Snus, and Camel Dissolvables that include Camel Orbs, Strips and Sticks. Those products are largely being positioned as complements to cigarette smoking, not substitutes, and we are likely to see a growth in dual product usage [10]. The primary target audiences in test marketing appear to be young people, not middle-age smokers looking to reduce their risks from smoking. Those companies also continue to heavily promote their traditional moist snuff products to young males, as evidenced by a 12-page advertising insert the January 2009 issue of Playboy magazine.
It remains to be seen whether snus or more traditional U.S. types of moist snuff will be adopted by smokers as substitutes for cigarettes, but so far they have not gained much traction [11]. While it is true that we may have a relatively U.S.-centric focus, we do note that nearly all U.S. states have achieved a lower prevalence of smoking than has Sweden. Even using the more stringent definition of daily smoking among persons age 15 years or older, about one-half of U.S. states have levels of smoking equal to or lower than Sweden's, with relatively little use of moist snuff despite its widespread availability.
8. “Both snus and Swedish tobacco control deserve some of the credit”. We obviously have a different interpretation of the situation in Sweden. Our skepticism and concerns are fueled, in part, by the lack of an evident public health benefit in neighboring Norway, which has seen a skyrocketing prevalence of snus usage among young males with no apparent impact on smoking initiation or cessation rates [3].
Disclosures
Scott Tomar is currently serving as an expert witness for plaintiffs in product liability law suits brought against a smokeless tobacco manufacturer and against a cigarette manufacturer.
Greg Connolly has no conflicts to disclose.
Scott L. Tomar
University of Florida College of Dentistry
Greg N. Connolly
Harvard School of Public Health
References
[1] Foulds J, Ramstrom L, Burke M, Fagerstrom K. Effect of smokeless tobacco (snus) on smoking and public health in Sweden. Tob Control. 2003;12(4):349-59.
[2] Bates C, Fagerstrom K, Jarvis MJ, Kunze M, McNeill A, Ramstrom L. European Union policy on smokeless tobacco: a statement in favour of evidence based regulation for public health. Tob Control. 2003;12(4):360-7.
[3] Tomar SL. Epidemiologic perspectives on smokeless tobacco marketing and population harm. Am J Prev Med. 2007;33(6 Suppl):S387-97.
[4] Ramstrom LM, Foulds J. Role of snus in initiation and cessation of tobacco smoking in Sweden. Tob Control. 2006;15(3):210-4.
[5] Lewin F, Norell SE, Johansson H, Gustavsson P, Wennerberg J, Biorklund A, et al. Smoking tobacco, oral snuff, and alcohol in the etiology of squamous cell carcinoma of the head and neck: a population-based case-referent study in Sweden. Cancer. 1998;82(7):1367-75.
[6] Schildt EB, Eriksson M, Hardell L, Magnuson A. Oral snuff, smoking habits and alcohol consumption in relation to oral cancer in a Swedish case-control study. Int J Cancer. 1998;77(3):341-6.
[7] International Agency for Research on C. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Vol. 89. Smokeless Tobacco and Related Nitrosamines. Lyon, France: IARC; 2007.
[8] Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR). Health Effects of Smokeless Tobacco Products. Brussels: European Commission, Health & Consumer Protection Directorate-General; 2008.
[9] Rasmussen F, Tynelius P, Kark M. Importance of smoking habits for longitudinal and age-matched changes in body mass index: a cohort study of Swedish men and women. Prev Med. 2003;37(1):1-9.
[10] Carpenter CM, Connolly GN, Ayo-Yusuf OA, Wayne GF. Developing smokeless tobacco products for smokers: an examination of tobacco industry documents. Tob Control. 2009;18(1):54-9.
[11] Zhu SH, Wang JB, Hartman A, Zhuang Y, Gamst A, Gibson JT, et al. Quitting Cigarettes Completely or Switching to Smokeless: Do U.S. Data Replicate the Swedish Results? Tob Control. 2009 Jan 23.
The authors quote a study by Boffetta et al to support the idea that
second-hand smoking causes disease. The Boffetta study does not support
that claim. Boffetta et al found no significant association between lung
cancer and passive smoking from spouse or workplace. They did find a
significant association with childhood exposure: those so exposed were
less likely to develop lung cancer.
The results of Boffetta et al are...
The authors quote a study by Boffetta et al to support the idea that
second-hand smoking causes disease. The Boffetta study does not support
that claim. Boffetta et al found no significant association between lung
cancer and passive smoking from spouse or workplace. They did find a
significant association with childhood exposure: those so exposed were
less likely to develop lung cancer.
The results of Boffetta et al are the reverse of what your authors claim.
Rodu is correct in stating that because the U.S. population is so
large, even a small percentage of cigarette smokers switching to smokeless
would mean many thousands of people [1]. However, he has done only half
the math- the other half is that exclusive smokeless users also switch to
cigarettes. In fact, it is easy to see from Table 2 in Zhu et al. that the
number switching from smokeless to cigarettes is much greater th...
Rodu is correct in stating that because the U.S. population is so
large, even a small percentage of cigarette smokers switching to smokeless
would mean many thousands of people [1]. However, he has done only half
the math- the other half is that exclusive smokeless users also switch to
cigarettes. In fact, it is easy to see from Table 2 in Zhu et al. that the
number switching from smokeless to cigarettes is much greater than the
number of smokers switching to smokeless [2]. The reason is that the rate
of switching from smokeless to cigarettes is more than 10 times higher
than the rate of switching from cigarettes to smokeless. One can use the
CPS 2002-2003 longitudinal sample with the proper population weights and
find that 120,266 people switched from smokeless to cigarettes, whereas
only 53,850 switched from cigarettes to smokeless. Someone else could use
these numbers to suggest that if more people use smokeless, more will use
cigarettes (although that is not the interpretation in Zhu et al.). That
is why it is important not to selectively choose numbers from Zhu et al.
and ignore the larger context [3].
Bergen and Phillips dismiss our empirical results as “not interesting
or useful to know” [4], and then they reiterate the well known arguments
for harm reduction. It is true that our results do not support Bergen and
Phillips’ position. Our paper strives to address pertinent arguments from
both sides of the harm reduction debate. After examining possible
explanations (socio-cultural, price, and product differences) for the
difference between the Swedish results and those that we found in the
U.S., we raise a cautionary note in our conclusion. Readers can judge for
themselves whether our paper is an anti-harm reduction opinion piece or a
careful empirical analysis. Interested readers with no access to the PDF
file for our paper can request a copy by sending an email to
szhu@ucsd.edu.
Conflict of Interest: None to declare
1. Rodu B. Evidence from Zhu et al. that American smokers have
switched to smokeless tobacco. Tob Control eLetter published online
February 20, 2009.
http://tobaccocontrol.bmj.com/cgi/eletters/tc.2008.028209v1#2853
2. Zhu S-H, Wang JB, Hartman A, Zhuang Y, Gamst A, Gibson T, et al.
Quitting cigarettes completely or switching to smokeless: Do U.S. data
replicate the Swedish results? Tob Control. Published Online First: 23
January 2009. doi:10.1136/tc.2008.028209
3. Zhu, S-H. Gamst, A. Response to Nitzkin and Rodu. Tob Control
eLetter published online February 11, 2009.
http://tobaccocontrol.bmj.com/cgi/eletters/tc.2008.028209v1#2837
4. Bergen P, Phillips CV. Response to Zhu et al. Tob Control eLetter
published online February 20, 2009.
http://tobaccocontrol.bmj.com/cgi/eletters/tc.2008.028209v1#2862
I thought I would revisit this debate some five years on,
only to find that the promised response (19 December
2003) has not yet been done.
None of the facts have changed much - those that wish
to intervene to prevent smokers choosing tobacco
products that are many times less hazardous still have
the upper hand - not in argument or evidence, but in
dominant public health approach and (in Europe) in the
most...
I thought I would revisit this debate some five years on,
only to find that the promised response (19 December
2003) has not yet been done.
None of the facts have changed much - those that wish
to intervene to prevent smokers choosing tobacco
products that are many times less hazardous still have
the upper hand - not in argument or evidence, but in
dominant public health approach and (in Europe) in the
most extraordinary and perverse legislation.
They might not like the to be labelled appropriately with
the blunt but accurate epithet "quit or die", but that is
the price of taking a position so strongly at odds with
evidence and ethics.
Come on.... it's never too late to put the record straight
and defend your work... or admit you were wrong. I
suspect this contribution will still be on the internet in
100 years time.
The authors of this paper (1), the responders (3), and most everyone
else agree that smoking is high risk, and that the use of smokeless
tobacco is fairly low risk. In any other area, the obvious conclusion
would be to encourage smokers to switch to the lower risk alternative.
However, what follows instead is a strange and yet quite common
argument that because many smokers might not switch, this alternative...
The authors of this paper (1), the responders (3), and most everyone
else agree that smoking is high risk, and that the use of smokeless
tobacco is fairly low risk. In any other area, the obvious conclusion
would be to encourage smokers to switch to the lower risk alternative.
However, what follows instead is a strange and yet quite common
argument that because many smokers might not switch, this alternative
should not be promoted. Whether or not most people will actually use a
low-risk alternative has never been a necessary precondition for promoting
or introducing it. Effectively, the authors suggest that because tobacco
harm reduction currently only saves the lives of a few thousand American
smokers per year, it should not be encouraged.
But this study actually tells us nothing about how many more might be
saved. Zhu et al. argue that their paper adds needed empirical data to
the discussion, but in fact they have merely measured something that is
not interesting or useful to know, and have confirmed something that no
one would ever doubt: They discovered that when a population of smokers
does not know that there is a low-risk alternative, then it is likely that
few of them will switch to it. Presumably no one would fail to predict
that, and reporting it says nothing about the potential benefits of
promoting harm reduction.
The authors acknowledge that smokers are unaware of the comparative
risks of tobacco use, and to their credit, point out that this shortfall
is something that the public health community must still address.
However, the authors mislead somewhat by stating that a reason that
switching may not have occurred at higher rates might be due to the fact
that despite its general availability, smokeless tobacco has not been
promoted as a safer alternative, when it is more the case that smokeless
tobacco has been actively discouraged as an alternative for smokers. Yes,
smokers can buy smokeless tobacco instead, but they do not know there is
good reason to do so. The lack of knowledge is the result of a concerted
(and successful) disinformation campaign by anti-tobacco extremists to
convince people that there are no low-risk nicotine products. Whatever
the present paper's empirical findings about historical switching rates,
such findings tell us almost nothing about how many smokers would switch
if they knew the truth.
If someone was interested in producing actual useful empirical
information, rather than just contributing to anti-harm-reduction
rhetoric, the most useful experiment would be to education a population
about the comparative risk and then observe how many smokers make the
switch. If few switched, then the authors' claims would actually be
supported. (Though their policy conclusions would still not be supported:
It would still be ethically mandated, as well as beneficial to some
extent, to tell smokers the truth about alternatives and encourage them to
switch, even if most of them chose not to do so.)
Perhaps the only interesting question that arises from this analysis
is why Swedish smokers switched to smokeless tobacco. Though a much
larger portion of Swedes know the truth than do Americans, many still
incorrectly think the risks from snus are similar to those from smoking.
Part of the explanation for the popularity of smokeless tobacco is
certainly cultural (or, put another way, an historical accident, an
economic "path dependence" resulting from social phenomena that trace back
about four decades). But part of the explanation is that, despite the
widespread lack of knowledge, Swedes are not being actively bombarded by
so much disinformation that it drowns out the truth. An American who
tries to learn the truth must learn to ignore the disinformation coming
from the U.S. national government, other government entities, and most
major self-styled health organizations, including some that are
respectable sources of advice in other areas (4), and sort through to the
rare accurate information that is available (e.g., 5, 6,7). (Nitzkin and
Rodu address this point well (2)). Moreover, an American who learns the
truth in spite of the disinformation and then wants to tell others needs
to then convince the others that most of the authorities they normally
trust are lying, making it quite difficult to spread the truth once it is
learned.
Despite being largely an historical accident, the Swedish experience
with tobacco harm reduction is still a great public health triumph. Zhu
et al. admit that tobacco harm reduction seems effective in Sweden but are
loathe to generalize or to suggest that we should even try to pursue such
triumph elsewhere. Extending their reasoning, consider this: In 1984, in
the United States roughly 14% of individuals used seatbelts (8), which is
less than half the prevalence in Sweden more than a decade earlier (9).
The general knowledge about the usefulness of seatbelts was similar in the
two countries, so there was clearly some cultural difference that resulted
in Americans adopting the restraints at a lower rate. Following Zhu et
al.'s logic, we should have just conceded that Americans are culturally
uninterested in using seatbelts, and that the Swedish success could not be
generalized.
Fortunately for the tens of thousands of Americans who have been
saved by seatbelts over the last few decades, in public health (in
contrast to anti-tobacco activism), we generally see success at reducing
harm as something to pursue and emulate rather than to dismiss as too
foreign to work.
Conflict of Interest
The authors' research is partially supported by an unrestricted
(completely hands-off) grant to the University of Alberta from U.S.
Smokeless Tobacco Company. Dr. Phillips has consulted for U.S. Smokeless
Tobacco Company in the context of product liability litigation. Dr.
Phillips is also a member of British American Tobacco's External Science
Panel that deals with developing reduced harm products.
References
1. Zhu S-H, Wang JB, Hartman A, Zhuang Y, Gamst A, Gibson JT et al.
Quitting cigarettes completely or switching to smokeless: do U.S. data
replicate the Swedish results? Tob Control; in press.
2. Zhu et al. Response to Nitzkin & Rodu's comments. Tob
Contol eLetter published online February 11, 2009.
3. Nitzkin JL, Rodu B. Promoting snus will save lives in the USA.
Tob Control eLetter published online February 6, 2009.
4. Phillips C, Wang C & Guenzel B. You might as well smoke:
the misleading and harmful public message about smokeless tobacco. 2005.
BMC Public Health 5:31.
5. Phillips C. Tobaccoharmreduction.org. (At:
http://www.tobaccoharmreduction.org)
6. Rodu B & Godshall WT. 2006. Tobacco harm reduction: an
alternative cessation strategy for inveterate smokers. Harm Reduction
Journal 3:37.
7. Royal College of Physicians. 2007. Harm reduction in nicotine
addiction: Helping people who can't quit. (Available at:
http://www.rcplondon.ac.uk/pubs/brochure.aspx?e=234)
8. Presidential Initiative for Increasing Seat Belt Use Nationwide:
Recommendations from the Secretary of Transportation. April 16, 1997.
http://www.nhtsa.dot.gov/people/injury/airbags/Archive-
04/PresBelt/fullreport.html
9. Phaner G & Hane M. 1979. Seat Belts: Opinion Effects of Law
Induced Use. Journal of Applied Psychology 64(2):205-212.
Zhu et al. reported that 0.3% of men who were exclusive current
smokers in 2002 became smokeless tobacco users at follow-up in 2003 (1).
Similarly, they reported that 1.7% of men who were former smokers of one
year or less duration and 0.3% of men who were former smokers for a longer
time were smokeless tobacco users in 2003.
These percentages are quite small, prompting the first author to
issue a statement in...
Zhu et al. reported that 0.3% of men who were exclusive current
smokers in 2002 became smokeless tobacco users at follow-up in 2003 (1).
Similarly, they reported that 1.7% of men who were former smokers of one
year or less duration and 0.3% of men who were former smokers for a longer
time were smokeless tobacco users in 2003.
These percentages are quite small, prompting the first author to
issue a statement in a press release that the research confirms that the
effects of smokeless tobacco use on smoking among Swedish men are unique
to Sweden (2). However, the study did not provide population estimates
for the American percentages.
Using SPSS statistical software with Complex Samples (Version 15.0
for Windows), I developed U.S. population estimates from the 2002 NHIS for
the number of male exclusive current and former smokers in that year, from
which I estimated the number who had switched to smokeless tobacco in 2003
as follows:
From exclusive current smokers in 2002: 70,416
From former smokers (<= 1 year): 52,058
From former smokers (> 1 year): 68,165
Total 190,639
Some might believe that 190,000 current or former smokers who became
smokeless tobacco users in this one-year period is an insignificant
number. But it is consistent with the results of a recent study using the
2000 National Health Interview Survey (3), in which 261,000 American men
had used smokeless tobacco to quit smoking. In that study switching to ST
compared very favorably with pharmaceutical nicotine, despite the fact
that few smokers know that the switch provides almost all of the health
benefits of complete tobacco abstinence. Taken together, these results
are proof of the concept that smokeless tobacco is a viable cessation
option for smokers in the U.S.
As long as American smokers are misinformed about the comparative
risks of ST and cigarettes, most will not consider trying to switch, or
will do so only reluctantly. A social and public health environment that
honestly informs smokers about comparative risks would provide many more
smokers with the opportunity to lead longer and healthier lives.
Conflict of Interest
Dr. Rodu is supported by unrestricted grants from smokeless tobacco
manufacturers (US Smokeless Tobacco Company and Swedish Match AB) to the
University of Louisville. The terms of the grants assure that the
sponsors are unaware of this work, and thus had no scientific input or
other influence with respect to its design, analysis, interpretation or
preparation of the manuscript.
References
1. Zhu S-H, Wang JB, Hartman A, et al. Quitting cigarettes
completely or switching to smokeless tobacco: do U.S. data replicate the
Swedish results. Tob Control 2008; in press.
2. UC San Diego News Center, available at:
http://ucsdnews.ucsd.edu/newsrel/health/01-09SmokelessTobacco.asp
(Accessed February 17, 2009)
3. Rodu B, Phillips CV. Switching to smokeless tobacco as a smoking
cessation method: evidence from the 2000 National Health Interview Survey.
Harm Reduction Journal 5: 18, 2008 (Open Access, available at
http://www.harmreductionjournal.com/content/pdf/1477-7517-5-18.pdf
Nitzkin and Rodu raise several interesting points about harm
reduction and how they would like to see the current FDA bill
(HR1108/S625) be improved [1]. However, the purpose of Zhu et al.’s paper
is not to advocate for or against harm reduction. It is simply to examine
whether current US data replicate the Swedish results [2].
If large numbers of US smokers could be induced to switch to
smokeless tobacco, tha...
Nitzkin and Rodu raise several interesting points about harm
reduction and how they would like to see the current FDA bill
(HR1108/S625) be improved [1]. However, the purpose of Zhu et al.’s paper
is not to advocate for or against harm reduction. It is simply to examine
whether current US data replicate the Swedish results [2].
If large numbers of US smokers could be induced to switch to
smokeless tobacco, that would certainly help to increase the population
smoking cessation rate. However, our study shows that very little
switching has occurred in the US population, unlike the Swedish
population. Smokeless tobacco has been promoted in both countries for a
long time, without a focus on relative risk. In light of these findings,
we sound a cautionary note. Tobacco control policymakers face difficult
choices, and our hope is that these new results might be helpful.
Nitzkin and Rodu’s arguments for the merits of harm reduction are
well known because there has been so much debate on this topic. Some are
convinced of such arguments while others are not [3,4]. Our paper aims to
inject empirical data into what sometime seems like an endless logical
exercise without new information. The debate is often filled with
hypothetical scenarios on how things might work this or that way. Some of
these hypotheses may turn out to be correct. Our paper does not say that
the hypotheses for harm reduction are wrong. It simply says that new
results from the US are quite different from the Swedish results and do
not support the idea that promoting smokeless tobacco necessarily leads to
increased smoking cessation on a population level. We believe that the
field needs more such empirical research.
That research can be misused, however, as in Nitzkin and Rodu’s
extrapolation of our finding that US men quit smokeless tobacco products
at three times the rate of quitting cigarettes. They suggest that this
means that “encouraging American smokers to switch to smokeless products
will increase the number that eventually quit all use of tobacco and
nicotine.” They ignore our larger finding that US smokers are not
switching to smokeless in the first place, and they fail to understand
that the differential quit rates suggest that, mathematically speaking, US
men tend to quit smokeless before quitting cigarettes. Are Nitzkin and
Rodu necessarily wrong, then, in suggesting such a hopeful scenario? We
would not say that. One can easily imagine various scenarios in which
smokeless tobacco helps smokers quit cigarettes or even all forms of
tobacco. But however enticing those scenarios may be, the US data do not
yet support them.
1. Nitzkin JL, Rodu B. Promoting snus will save lives in the USA. Tob
Control eLetter published online February 6, 2009.
2. Zhu S-H, Wang JB, Hartman A, Zhuang Y, Gamst A, Gibson JT et al.
Quitting cigarettes completely or switching to smokeless: do U.S. data
replicate the Swedish results? Tob Control; in press.
3. Rodu B, Godshal WT. Tobacco harm reduction: an alternative
cessation strategy for inveterate smokers. Harm Reduction J 2006;3:37.
Open access, available at:
http://www.harmreductionjournal.com/content/3/1/37 (Accessed February 10,
2009).
4. Tomar SL, Fox BJ, Severson HH. Is smokeless tobacco use an
appropriate public health strategy for reducing societal harm from
cigarette smoking? Int J Environ Res. Pub Health 2009, 6(1), 10-24;
doi:10.3390/ijerph6010010
Zhu, et al., when comparing tobacco-related behaviors in the U.S. and
Sweden concluded that “promoting smokeless tobacco for harm reduction in
countries with ongoing tobacco control programs may not result in any
positive population effect on smoking cessation.” [1]
We believe that this conclusion is too pessimistic.
Promotion of snus in the U.S., as a low-risk alternative for smokers
unable or unwillin...
Zhu, et al., when comparing tobacco-related behaviors in the U.S. and
Sweden concluded that “promoting smokeless tobacco for harm reduction in
countries with ongoing tobacco control programs may not result in any
positive population effect on smoking cessation.” [1]
We believe that this conclusion is too pessimistic.
Promotion of snus in the U.S., as a low-risk alternative for smokers
unable or unwilling to quit has great potential to substantially reduce
tobacco-related illness and death. Snus and selected other smokeless
nicotine delivery products can eliminate all risks from fire, second hand
smoke, all pulmonary disease, most cardiac disease and most cancer
attributable to smoking. These products are up to 1000 times less
hazardous than cigarettes.[2,3] Thus, if large numbers of smokers replace
some or all of their cigarettes with low-risk alternatives, a substantial
reduction in tobacco-related illnesses and death will occur. This will be
true even if large numbers of non-smokers initiate use of these smokeless
products.
Zhu et al. concede that “…in the U.S., smokeless tobacco has not been
promoted as a safer alternative to cigarettes.” But the American
environment is even worse: current federal tobacco policy incorrectly
labels a smokeless tobacco product as “not a safe substitute for
cigarettes,” which has left most Americans – even healthcare professionals
– with the misimpression that smokeless products are as hazardous as
cigarettes.[4,5]
The popularity of “light” and “low tar” cigarettes in the U.S. has
clearly demonstrated that large numbers of American smokers will switch to
products that appear to be of lower risk, if encouraged to do so. While
the implied health claims for “light” and “low tar” cigarettes were
fraudulent, the well established differences in risk between cigarettes
and smokeless tobacco products are not.[6]
One of the more intriguing findings in the Zhu paper is that “men
quit smokeless tobacco products at three times the rate of quitting
cigarettes (38.8% vs. 11.6%, p<0.001).”[1] This raises the possibility
that encouraging American smokers to switch to smokeless products will
increase the number that eventually quit all use of tobacco and nicotine.
Many opposed to such an approach claim that “conventional nicotine-
replacement therapies…have been tested extensively and shown…to be
effective.”[7] Such statements, however, rarely show the quit rates. One
recently published study boasts that nicotine gum more than doubles the
quit rate. The data show 6-month quit rates of 2.1% in controls and 5.9%
in study subjects.[8] The authors fail to mention that the therapy failed
for 94% of study subjects. We need to do much better than that if we are
to achieve substantial reductions in tobacco-related illness and death.
Zhu et al. acknowledge – then gloss over – the fact that the rate of
tobacco-related illness and death are far lower in Sweden, where snus is
popular, than in the U.S., where cigarettes are dominant. Data from the
World Health Organization and the International Agency for Research on
Cancer show that lung cancer rates among both Swedish men and women were
well under half the rates for their American counterparts from 1980 to
2002.[9] But the data reveal another amazing fact: since 1989 lung cancer
among Swedish men has been lower than that among American women. This is
evidence that snus use suppresses smoking, with the important context that
per capita nicotine consumption is nearly identical in both countries.[10]
Furthermore, the Swedish government neither promotes snus for harm
reduction nor vilifies it as “not a safe substitute for cigarettes.”
The time has come for American legislators and public health leaders
to educate smokers as to the differences in risk profiles between
cigarettes and other tobacco products. This will empower smokers who are
unable or unwilling to quit to reduce their risk of tobacco-related
illness, even while locked into their nicotine addiction. The potential
public health benefit is substantial.
Those opposed to such an approach theorize that smokeless tobacco
manufacturers “will inevitably target susceptible adolescents,”[7]
creating users who may then transition to cigarettes. They also point out
that there is no empirical evidence that such a policy (helpful
information to smokers) will generate the projected public health
benefits. Whether or not such a program results in increases in teen
tobacco use will depend entirely on how it is framed and how it is placed
in the context of other tobacco control efforts. As to the projected
public health benefits, there will be no way to know for sure without
implementing the policy, then carefully tracking the results. A national
program in the U.S. that includes helpful health education, effective
regulation, and robust surveillance and research programs should be able
to make the mid-course corrections needed to assure optimal outcomes from
a public health perspective.
A piece of legislation was introduced into the recently concluded
110th U.S. Congress. The bill (HR1108/S625) was known as the “Family
Smoking Prevention and Tobacco Control Act.” Unfortunately, this bill, as
seen by the American Association of Public Health Physicians, is a total
failure with regard to the desired health education. It also fails to
effectively regulate tobacco products and strongly favors currently
marketed cigarettes. We hope it will be possible to amend the bill in the
current Congress so that it will provide the needed health education,
effective regulation, surveillance and research.[11]
The relative safety of snus and the latest generation of alternative
smokeless nicotine delivery products is not a children’s issue. The eight
million Americans who will die from smoking-related illnesses in the next
twenty years are now 35 years of age and older. Preventing youth access
to tobacco is vitally important, but should not be used as an excuse to
condemn smoking parents and grandparents to premature death, especially
within socially and economically disadvantaged sub-populations. If
implemented as an addition to otherwise effective tobacco control
programming, the helpful information to smokers should not significantly
increase the numbers of teens initiating tobacco use.[11]
Conflict of Interest
Dr. Nitzkin has never sought nor secured any financial or other
support from any tobacco-related enterprise. Dr. Rodu is supported by
unrestricted grants from smokeless tobacco manufacturers (US Smokeless
Tobacco Company and Swedish Match AB) to the University of Louisville.
The terms of the grants assure that the sponsors are unaware of this work,
and thus had no scientific input or other influence with respect to its
design, analysis, interpretation or preparation of the manuscript.
References
1. Zhu S-H, Wang JB, Hartman A, et al. Quitting cigarettes
completely or switching to smokeless tobacco: do U.S. data replicate the
Swedish results. Tob Control 2008; in press.
2. Royal College of Physicians of London. Protecting smokers,
saving lives: the case for a tobacco and nicotine authority. London,
England, 2002. Available at:
http://www.rcplondon.ac.uk/pubs/books/protsmokers/index.asp (Accessed
February 5, 2009).
3. Nitzkin JL, Rodu B. The case for harm reduction for control of
tobacco-related illness and death. Resolution and White Paper, Adopted by
the American Association of Public Health Physicians, October 26, 2008.
Open access, available at:
http://www.aaphp.org/special/joelstobac/20081026HarmReductionResolutionAsPassedl.pdf
(Accessed February 5, 2009).
4. O’Connor RJ, Hyland A, Giovono G, et al. Smoker awareness of and
beliefs about supposedly less harmful tobacco products. Am J Prev Med
2005;29:85-90.
5. O’Connor RJ, McNeill A, Borland R, et al. Smokers’ beliefs about
the relative safety of other tobacco products: findings from the ITC
Collaboration. Nicotine Tob Res 2007;9:1033-1042.
6. Rodu B, Godshall WT. Tobacco harm reduction: an alternative
cessation strategy for inveterate smokers. Harm Reduction J 2006;3:37.
Open access, available at:
http://www.harmreductionjournal.com/content/3/1/37 (Accessed February 5,
2009).
8. Shiffman S, Ferguson SG, Strahs KR. Quitting by gradual smoking
reduction using nicotine gum: a randomized controlled trial. Am J Prev
Med 2009;36:96-104.
9. World Health Organization Mortality Database. Accessed through
the Descriptive Epidemiology Group, Biostatistics and Epidemiology
Cluster, International Agency for Research on Cancer, Lyon, France at:
http://www-dep.iarc.fr/
10. Fagerström K. The nicotine market: an attempt to estimate the
nicotine intake from various sources and the total nicotine consumption in
some countries. Nicotine Tob Res 2005;7:343-350.
11. Analysis and Recommendations for Amendment of FDA/Tobacco Bill.
American Association of Public Health Physicians, November 5, 2008. Open
access, available at:
http://www.aaphp.org/special/2009/20081105_AnalRcommendFDATobcBill.pdf
(Accessed February 5, 2009).
A recent article in Tobacco Control 1 reported that 33% of cigarettes
are consumed by smokers who had a current mental disorder. The title,
abstract and discussion of that article stated that this 33% represented
how much “mental disorders contribute to tobacco consumption in New
Zealand.” This statement is misleading for at least two reasons. First,
although 33% of smokers had a current mental disorder, 21% of nonsmok...
A recent article in Tobacco Control 1 reported that 33% of cigarettes
are consumed by smokers who had a current mental disorder. The title,
abstract and discussion of that article stated that this 33% represented
how much “mental disorders contribute to tobacco consumption in New
Zealand.” This statement is misleading for at least two reasons. First,
although 33% of smokers had a current mental disorder, 21% of nonsmokers
also had a current mental disorder; thus, the actual excess that mental
disorders could “contribute” is +12%, not 33%. Second, and more
importantly, neither this study nor the prior literature has consistently
shown that mental disorders per se cause the initiation of smoking, cause
smokers to smoke more or interfere with cessation 2. For example, recent
reviews have concluded that prior alcohol dependence and depression do not
appear to impair smoking cessation 3,4.
Since we cannot randomize smokers to mental illness, we must rely on
associative data. Among the criteria for judging whether an association
is causal 5, the plausibility, replicability, strength of the association,
dose-responsivity of the association, and the consistency with other
knowledge argue for causality. However, data on whether smoking remits
if mental disorders remit, whether the association persists when all
reasonable confounds are considered, evidence of specificity, and temporal
relationship do not strongly argue causality. For example, a) most
mental disorders temporally follow, not precede, smoking, b) those in
remission from a psychiatric disorder have not been shown to stop smoking
and c) smoking is associated with over 20 different mental disorders
suggesting nonspecificity 2. Finally, even if the association was causal,
it is unlikely that mental illness accounts for 100% of the reason these
smokers smoke. If it accounted for only half, then the excess due to
mental disorders would be only +6% (half of +12%). In summary, the
“contribution” of psychiatric co-morbidity to the current prevalence of
smoking is likely much less than the stated 33%.
References
1. Tobias M, Templeton R, Collings S. How much do mental disorders
contribute to New Zealand's tobacco epidemic? Tobacco Control 2008;17:347-
350.
2. Hughes JR. Comorbidity and smoking. Nicotine and Tobacco Research
1999;1:S149-152.
3. Hughes JR, Kalman D. Do smokers with alcohol problems have more
difficulty quitting? Drug Alcohol Depend 2005;82:91-102.
4. Hitsman B, Borrelli B, McChargue DE, Spring B, Niaura R. History
of depression and smoking cessation outcome: A meta-analysis. J Consult
Clin Psychol 2003;71:657-663.
5. Hill AB. The environment and disease: Association or causation?
295-300. 1965.
It is known that smoking increases DHEAS, the precursor of DHEA. The
same should happen because of exposure to secondhand smoke.
DHEA is the active molecule, so increases in DHEAS may indicate that
smoking is reducing DHEA. DHEA is known to be important to normal
pregnancy-associated outcomes.
I suggest the findings of Peppone, et al., may be explained by
reduced DHEA in these women.
First, an apology is in order for taking so long to respond to the online discussion surrounding the review by Foulds et al. [1] and the opinion piece by Bates et al. [2]. As we had promised in our earlier reply to Foulds et al. (19 December 2003) and have been reminded by Bates, we are belatedly responding to the specific points raised by Foulds et al. in their e-letter dated 5 December 2003:
1. “Misrepresentation of...
The authors quote a study by Boffetta et al to support the idea that second-hand smoking causes disease. The Boffetta study does not support that claim. Boffetta et al found no significant association between lung cancer and passive smoking from spouse or workplace. They did find a significant association with childhood exposure: those so exposed were less likely to develop lung cancer. The results of Boffetta et al are...
Rodu is correct in stating that because the U.S. population is so large, even a small percentage of cigarette smokers switching to smokeless would mean many thousands of people [1]. However, he has done only half the math- the other half is that exclusive smokeless users also switch to cigarettes. In fact, it is easy to see from Table 2 in Zhu et al. that the number switching from smokeless to cigarettes is much greater th...
I thought I would revisit this debate some five years on, only to find that the promised response (19 December 2003) has not yet been done.
None of the facts have changed much - those that wish to intervene to prevent smokers choosing tobacco products that are many times less hazardous still have the upper hand - not in argument or evidence, but in dominant public health approach and (in Europe) in the most...
The authors of this paper (1), the responders (3), and most everyone else agree that smoking is high risk, and that the use of smokeless tobacco is fairly low risk. In any other area, the obvious conclusion would be to encourage smokers to switch to the lower risk alternative.
However, what follows instead is a strange and yet quite common argument that because many smokers might not switch, this alternative...
Zhu et al. reported that 0.3% of men who were exclusive current smokers in 2002 became smokeless tobacco users at follow-up in 2003 (1). Similarly, they reported that 1.7% of men who were former smokers of one year or less duration and 0.3% of men who were former smokers for a longer time were smokeless tobacco users in 2003.
These percentages are quite small, prompting the first author to issue a statement in...
Nitzkin and Rodu raise several interesting points about harm reduction and how they would like to see the current FDA bill (HR1108/S625) be improved [1]. However, the purpose of Zhu et al.’s paper is not to advocate for or against harm reduction. It is simply to examine whether current US data replicate the Swedish results [2].
If large numbers of US smokers could be induced to switch to smokeless tobacco, tha...
Zhu, et al., when comparing tobacco-related behaviors in the U.S. and Sweden concluded that “promoting smokeless tobacco for harm reduction in countries with ongoing tobacco control programs may not result in any positive population effect on smoking cessation.” [1]
We believe that this conclusion is too pessimistic.
Promotion of snus in the U.S., as a low-risk alternative for smokers unable or unwillin...
A recent article in Tobacco Control 1 reported that 33% of cigarettes are consumed by smokers who had a current mental disorder. The title, abstract and discussion of that article stated that this 33% represented how much “mental disorders contribute to tobacco consumption in New Zealand.” This statement is misleading for at least two reasons. First, although 33% of smokers had a current mental disorder, 21% of nonsmok...
It is known that smoking increases DHEAS, the precursor of DHEA. The same should happen because of exposure to secondhand smoke.
DHEA is the active molecule, so increases in DHEAS may indicate that smoking is reducing DHEA. DHEA is known to be important to normal pregnancy-associated outcomes.
I suggest the findings of Peppone, et al., may be explained by reduced DHEA in these women.
Pages