Smokeless tobacco (ST) is that which is used orally and most often comes as chewing tobacco or snuff – a moist ground tobacco. Approximately 90% of the world’s users of smokeless tobacco reside in Southeast Asia but it is used, often from a young age, all around the world.

ST is associated with a number of systemic and oral diseases including cardiovascular disease and oral cancer, though the associations are not nearly as strong as for smoked tobacco. For this reason it has been proposed as a means to assist smokers using a harm-reduction approach, which is contentious and there is guidance for the healthcare sector to help reduce ST use

The aims of this review were to assess the effects of behavioural and pharmacotherapeutic interventions to treat smokeless tobacco (ST) use.

Methods

The authors searched the Cochrane Central Register of Controlled trials (CENTRAL); MEDLINE; EMBASE; and PsycINFO. Additional sources were also searched in early versions of the review: Web of Science, Dissertation Abstracts Online, Scopus, Healthstar, ERIC, National Technical Information Service database, and Current Contents.

Randomised controlled trials and pseudo-randomised controlled trials allocating smokeless tobacco (ST) users to an intervention or control, or to different interventions. Interventions could be pharmacological (i.e. nicotine replacement therapy (NRT), bupropion, varenicline) or behavioural, and could be directed at individual ST users or at groups of users.

Results

Pharmacological interventions

• Bupropion, an antidepressant, has been shown to be effective in helping smokers to quit (Hughes et al 2014) but in this review two studies found no effect on tobacco use quitting.
• Nicotine lozenges did show an improvement in quit rates with a relative risk of 1.36 (95% CI 1.17-1.59). That is, those using lozenges compared to placebo were 36% more likely to give up.
• Nicotine gum and patches did not tend towards a significant benefit over placebo.
• Varenecline, which has also been shown to be beneficial in helping smokers quit was similar in effect to the nicotine lozenges, with a relative risk of abstinence of 1.34 (95% CI 1.08-1.68).

Behavioural interventions

• Behavioural interventions were varied and difficult to summarise here. They included interventions based on the Health Belief Model, Social Learning Theory, Transtheoretical Model of Change, Cognitive Social Learning Theory, Diffusion of Innovations and many more.
• Seven studies selected participants who were already motivated to stop using smokeless tobacco and had a relative risk of abstinence from tobacco of 1.39 (95% CI 1.25-1.55). In those studies that selected anyone to participate the relative risk was only marginally lower at 1.37 (95% CI 1.23-1.53).
• By including telephone support in the intervention the relative risk increased to 1.77 (95% CI 1.57-2.00). When an oral examination was combined with telephone support the relative risk increased to 2.07 (95% CI 1.61-2.66). That is, the likelihood of long term abstinence is doubled.

Conclusions

The authors concluded:

Varenecline, nicotine lozenges and behavioural interventions could help to reduce ST use but confidence in the effectiveness of nicotine lozenges and behavioural interventions is far weaker than for Varenecline.

Comments

This systematic review addresses an important question and has been conducted well. The problem is the included studies were not conducted where the majority of ST users are (they were all conducted in North America or Europe) and so the external validity of the primary studies is limited given the different cultural norms around tobacco use in other parts of the world. We would expect this particularly to impact on the effectiveness of behavioural interventions.

As dentists, we are not able to prescribe Varenecline and, anyway, its prescription may be better managed as part of a specialist smoking cessation service where short term (4 weeks) quit rates are approximately 35% ( West et al 2013) . The UK’s National Institute for Health and Care Excellence (NICE) has produced guidance on how to help Southeast Asian users of smokeless tobacco to quit  and Public Health England guidance for those involved in commissioning and delivering oral health care to help all tobacco users to quit.

Links

Primary paper

Ebbert JO, Elrashidi MY, Stead LF. Interventions for smokeless tobacco use cessation. Cochrane Database of Systematic Reviews 2015, Issue 10. Art. No.: CD004306. DOI: 10.1002/14651858.CD004306.pub5.

Other references

Hughes JR, Stead LF, Hartmann-Boyce J, Cahill K, Lancaster T. Antidepressants for smoking cessation. Cochrane Database Syst Rev. 2014;1:CD000031. doi:10.1002/14651858.CD000031.pub4.

West R, May S, West M, Croghan E, McEwen A. Performance of English stop smoking services in first 10 years: analysis of service monitoring data. BMJ. 2013 Aug 19;347:f4921. doi: 10.1136/bmj.f4921. PubMed PMID: 23963106.