Snus use in Sweden: another reply to Tomar.

I have previously discussed the role of snus in reducing smoking in Sweden, and criticized the IARC report’s coverage of this issue. Professor Scott Tomar (a member of the IARC committee) stated (as a comment to a posting criticising the new IARC monograph on smokeless tobacco):
“Using official Swedish data for smoking for 2004 (from the ULF survey conducted by Statistics Sweden), smoking quit rates (or what some call smoking quit ratios, defined as the proportion of ever smokers who are now former smokers), by age group and sex are:Age 16–24Men 13.2%Women 14.6%Age 25–44Men 37.8%Women 38.3%Age 45–64Men 54.5%Women 51.7% “

However, a colleague of mine based in Sweden (Lars Ramstrom), who is very familiar with Swedish surveys on tobacco use, has informed me that these figures on Swedish tobacco statistics are inaccurate in two ways:
1. They provide inaccurate numerical values for “the proportion of ever smokers who are now former smokers”
2. They inaccurately claim that the figures come from “the ULF survey conducted by Statistics Sweden”.

Statistics Sweden generally does not publish any figures on “the proportion of ever smokers who are now former smokers”. The main reason is that their ULF survey uses a questionnaire that does not include enough items to identify the subgroup “former occasional but never daily smokers who are now former smokers”. Since this subgroup must be part of both numerator and denominator of the calculation of such proportions, the ULF data are just unable to provide a basis for such calculations.

For this reason, we believe that the figures provided by Professor Tomar are likely to be inaccurate. However, the proportions in question can be calculated from other surveys that are performed by the Swedish research institute FSI, Research Group for Information and Societal Studies. These surveys are described in the literature (Ramström LM, Foulds J. Role of snus in initiation and cessation of tobacco smoking in Sweden. Tob. Control 2006;15;210-214). Using the same data base as the just mentioned article we get the following data:

Proportion of ever smokers (daily plus non-daily)
who are now former smokers
Age span Men Women
16-79 61% 54%
16-24 49% 42%
25-44 54% 53%
45-64 63% 55%
65-79 75% 68%

Professor Tomar made a point about the “similarity” between males and females quitting based on his original figures.
“Please explain why the quit rates in Sweden are so similar for men and women within each age stratum if snus had such a dramatic effect on cessation?”

In these figures we can see similarity in one age group only, 25-44. In this very age group a large proportion of women are planning or going through pregnancy and are thereby met the very forceful encouragement and treatment for quitting smoking that is very well established in the Swedish maternal health care system. This is a gender-specific condition that explains why this age group shows a different men/women comparison than the others.

The relevant question is rather opposite to the one asked by Professor Tomar:

Why are overall quit rates generally higher in men than in women in Sweden?

The answer is given by the following data picked up from the above mentioned article:
(These data refer to quit rate for daily smoking, while the data above refer to quit rate for all smoking. Therefore the numerical values differ a little)

Proportion of ever daily smokers
who are now former smokers
Men Women
Overall 59% 49%
With a history of daily snus use 72% 71%
Without history of daily snus use 51% 48%

These data illustrate that gender comparisons have to be made between truly comparable subgroups in order to yield meaningful conclusions.

In each one of the two lower lines there are comparisons between men and women who are comparable with respect to snus use. In each case there is no difference.

In each one of the gender columns the two lower lines give gender-specific comparisons indicating the influence of snus use. Both for men and women there are large differences in quit rate according to presence or absence of a history of snus use.

The above observations demonstrates that the overall difference between men and women does not stem from factors related to gender itself but to the fact that snus use, as a cessation promoting factor, is more prevalent among men than among women.

In summary, contrary to Professor Tomar’s thesis, the Swedish statistics on smoking cessation suggest that snus use is having a substantial effect in promoting cessation of smoking among men. Of course this is self evident from the simple fact that 24-30% of male Swedish ex-smokers used snus to quit smoking. My thanks to Lars Ramstrom for providing clarification on the pattern of tobacco use in Sweden.

Incidentally, the issue of snus for smoking cessation was recently debated in the British Medical Journal, at:
http://www.bmj.com/cgi/content/full/336/7640/358

For the record (again), I don’t believe that health professionals should recommend snus to their patients. I believe that we have medicines and counseling that can be effective treatments for addiction to cigarettes (or at least as efficacious as snus) and that these are what we should be recommending to patients. However, I do believe that the public should have accurate information about the relative risks of snus and cigarettes. Currently the public underestimates the risks from cigarettes, relative to snus or nicotine replacement therapy.

Labels: jonathan foulds, nicotine, nicotine nasal spray smoking cessation, smokeless, snus, tobacco

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Snus use in Norway.

Snus is a form of smokeless tobacco that is widely used – primarily by men – in Sweden. It is characterized by being relatively low in toxins but delivers about as much nicotine as a cigarette. It is not harmless (causes gum erosion, and pancreatic cancer) but has been estimated to be about 90% less harmful than smoking cigarettes (no lung cancer, oral cancer, or chest diseases).

In Sweden more men now use snus on a daily basis than smoke, and about a quarter of Swedish men who quit smoking did so by switching to snus. Consequently Sweden is just about the only country in the world in which it is consistent that fewer men smoke than women. As I’ve previously discussed, multinational tobacco companies are now test-marketing their own snus products, including in then US. However, some doubt remains as to whether this product (which is banned in the European Union, Australia and New Zealand) could become popular in another country.

A report has just been published on tobacco use in Norway (which is not a member of the EU), which shows a fairly dramatic increase in snus use among young men.
http://www.shdir.no/publikasjoner/faktahefter/tall_om_tobakk_1973_2006_13509

This report found that in the period 2004-6 10% of men used snus on a daily basis and 7% on an occasional basis (compared to 7% and 6% in 2001-3). However, the proportion of users is much higher in young men, with 17% using daily and 17% occasionally in the 16-24 age group. Overall the proportion of daily snus users among men aged 16-44 has more than quadrupled from 1985 to 2006. It remains to be seen what the effects of this expansion of snus use is on smoking rates and health effects. Figure 24 in the report shows that of 631 men who successfully quit smoking during the period 1990-2006 and were surveyed in 2004-6, 17% quit smoking by using snus – a proportion equal to the number who quit by using the nicotine gum (10%), patch (4%) and Zyban (3%) added together. Most Norwegan male ex-smokers quit without any assistance, and 1% used the national telephone helpline. This suggests that a meaningful proportion of men are quitting smoking by switching to snus in Norway. Clearly no tobacco use is preferable to use of smokeless tobacco, and approved medicines are preferable as smoking cessation aids. But anything that gets people to quit smoking has the potential to reduce the harm to health in then population.

If you are interested in learning more about snus, and the effects it has had on smoking in Sweden, click on this link: http://www.tobaccoprogram.org/staffarticles.htm, scroll down to the papers by Foulds and colleages (2003) on “The Effect of smokeless tobacco (snus) on smoking and public health in Sweden” and the paper by Ramstrom & Foulds (2006). These are both available as pdfs for free from this site.

Labels: nicotine, smokeless, snus, tobacco

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Marlboro Snus: What is it?

Yesterday Philip Morris USA, the tobacco company that has around 50% of the total market for cigarettes in the USA, announced the launch a new product: “Marlboro Snus,” in a test market in the Dallas/Fort Worth area. So what type of product it this?

As this particular brand of snus won’t be launched until August we can’t yet tell much of the details of the product (e.g. how much nicotine it delivers or how much it will cost) so lets talk about what “snus” is generally, and why the biggest cigarette manufacturers in the US are test marketing an entirely different type of product.

Snus (pronounced “snooss”) is the Swedish word for snuff, and is a form of moist ground smokeless tobacco, that is usually sold in “sachet” form – each sachet looking like a small tea-bag. Each sachet is placed in the mouth (usually under the upper or lower lip) for about 30 minutes and the nicotine and tobacco taste is absorbed via the lining of the mouth. The main difference between snus products and other smokeless tobacco already available in the United States, is that snus is produced using a process like pasteurization in which it is heated with steam. This kills most of the microbes that can produce cancer-causing chemicals in tobacco. Traditional smokeless products like Skoal and Copenhagen are not pasteurized but are fermented - a process that facilitates the development of cancer-causing chemicals. So snus does not appear to cause oral cancer. Clearly smokeless products also don’t cause lung cancer or respiratory diseases like emphysema either. That’s not to say that snus is entirely safe. Long term use can cause white patches to appear on the lining of the mouth and erosion of the gum where it is placed, and decades of use may increase risks of pancreatic cancer and cardiovascular disease (e.g. stroke and heart attacks). The nicotine from this product will also harm the unborn baby when used by a pregnant woman. So neither snus nor any other form of smokeless tobacco is recommended for anyone who currently doesn’t smoke. But because the health risks from snus are much lower (about 90% lower) than from smoking this may be a step in the right direction for the smoker who wants to keep using tobacco but wants to avoid most of the health risks.

Other companies are also test marketing snus products in the US. For example, Reynolds are launching Camel Snus, and Swedish Match are marketing “Exalt” in the US. So why are the big tobacco companies starting to test-market this product? The most likely reason is that they are aware that indoor smoking bans are sweeping the country, making it more hassle to be a smoker. They know that for a proportion of smokers the hassle of going in and out of nicotine withdrawal and being blamed for inflicting their smoke on other people makes it just not worth it, and will prompt many smokers to quit each year. I think they see snus as a way to get smokers to use their smokeless product in smoke-free environments, (so avoiding nicotine withdrawal and social stigma) but to continue smoking their cigarette brand in places where it is allowed. Clearly if smokers who would otherwise have quite continue to use both cigarettes and snus, this is a bad outcome for public health.

The use of the brand name “Marlboro” for their snus product suggests that the company may be serious about selling this product, and also suggests an intent to link it to their cigarette brands.

For those interested in quitting smoking, the best advice is to use one or more FDA-approved smoking cessation medications and enrole in counseling with a smoking cessation specialist.

If you are interested in learning more about snus, and the effects it has had on smoking in Sweden, click on this link: http://www.tobaccoprogram.org/staffarticles.htm
, scroll down to the papers by Foulds and colleages (2003) on “The Effect of smokeless tobacco (snus) on smoking and public health in Sweden” and the paper by Ramstrom & Foulds (2006). These are both available as pdfs for free from this site.

Labels: nicotine addiction cigarette smoking tobacco, snus

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