Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-12-06T16:25:07.992Z Has data issue: false hasContentIssue false

Systematic review of Swedish snus for smoking cessation based on primary subject data from randomised clinical trials

Published online by Cambridge University Press:  10 April 2013

L. E. Rutqvist*
Affiliation:
Scientific Affairs Group, Swedish Match AB, Stockholm, Sweden
J. S. Fry
Affiliation:
P. N. Lee Statistics and Computing Ltd, Sutton, Surrey, UK
P. N. Lee
Affiliation:
P. N. Lee Statistics and Computing Ltd, Sutton, Surrey, UK
*
Address for correspondence: Lars Erik Rutqvist, MD, PhD, Swedish Match AB, Maria Skolgata 83, SE-118 85, Stockholm, Sweden. Email: lars-erik.rutqvist@swedishmatch.com

Abstract

Introduction: The ability of Swedish snus to serve as a smoking cessation aid has been documented in several observational, population surveys from Scandinavia, but randomised clinical trials provide more reliable information on efficacy. Aims: To perform a systematic review and meta-analysis of randomised clinical trials of Swedish snus as an aid to smoking cessation. Methods: Literature searches were conducted in MedLine, Cochrane Library, and Embase to identify relevant clinical trials. The primary outcome was defined as biologically confirmed smoking cessation during around six months. Meta-analyses based on primary subject data tested for effect of allocated treatment as well as selected baseline characteristics. Results: There were two relevant clinical trials, one conducted at five sites in the US (n = 250), the other at two sites in Serbia (n = 319). Based on the primary outcome, success was higher in the treated group in both Serbia (5.7% vs 1.9%) and the US (4.0% vs 1.6%). Meta-analysis estimated the relative success rate at 2.83 (95% CI 1.03–7.75), which was of borderline significance (exact p = 0.06, chi-squared p = 0.03). For smoking cessation in the last 4 weeks of each study, rates were 12.4% for snus and 6.6% for placebo (RR 1.86, 95% CI 1.09-3.18). Efficacy of snus was not clearly related to any baseline characteristic. Conclusions: Swedish snus increased quit rates similarly in US and Serbia. These results confirm and extend previous information based on observational population surveys.

Type
Articles
Copyright
Copyright © The Authors 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Royal College of Physicians (ed.). (2002). Protecting smokers, saving lives: the case for a tobacco and nicotine regulatory authority. London: Royal College of Physicians. http://www.rcplondon.ac.uk/pubs/books/protsmokers/ProtSmokers.pdfGoogle Scholar
Breslow, N. E., & Day, N. E. (1980). The analysis of case-control studies. Vol. 1. Statistical methods in cancer research, Davis, W. (Ed.). (IARC Scientific Publication No. 32.) Lyon: IARC.Google Scholar
Conover, W. J. (2003). Practical nonparametric statistics. 3rd edition. Wiley series in probability and mathematical statistics, Bradley, R. A., Hunter, J. S., Kendall, D. G., & Watson, G. S. (Eds.). New York, Chichester, Brisbane, Toronto: John Wiley & Sons.Google Scholar
Fagerström, K., Rutqvist, L., & Hughes, J. (2011). Snus as a smoking cessation aid: a randomized, placebo-controlled trial. Nicotine & Tobacco Research, 14, 306312.CrossRefGoogle Scholar
Fleiss, J. L., & Gross, A. J. (1991). Meta-analysis in epidemiology, with special reference to studies of the association between exposure to environmental tobacco smoke and lung cancer: a critique. Journal of Clinical Epidemiology, 44, 127139.Google Scholar
Foulds, J., Ramström, L., Burke, M., & Fagerström, K. (2003). Effect of smokeless tobacco (snus) on smoking and public health in Sweden. Tobacco Control, 12, 349359.Google Scholar
Fry, J. S., & Lee, P. N. (1991). A stratified Wilcoxon-type test for trend (Letter). Statistics In Medicine, 10, 799800.Google Scholar
Greenland, S., & Robins, J. M. (1985). Estimation of a common effect parameter from sparse follow-up data. Biometrics, 41, 5568.Google Scholar
Heatherton, T.F., Kozlowski, L.T., Frecker, R.C., & Fagerström, K.O. (1991). The Fagerström test for nicotine dependence: a revision of the Fagerström tolerance questionnaire. British Journal of Addiction, 86, 11191127.Google Scholar
Holm, L.-E., Fisker, J., Larsen, B.-I., Puska, P., & Halldórsson, M. (2009). Snus does not save lives: quitting smoking does! Tobacco Control, 18, 250251.Google Scholar
Hughes, J. R., Benowitz, N., Hatsukami, D., Mermelstein, R. J., & Shiffman, S. (2004). Clarification of SRNT workgroup guidelines for measures in clinical trials of smoking cessation therapies. Nicotine & Tobacco Research, 5, 863864.Google Scholar
Hughes, J. R., & Carpenter, M. J. (2006). Does smoking reduction increase future cessation and decrease disease risk? A qualitative review. Nicotine & Tobacco Research, 8, 739749.Google Scholar
Joksic, G., Spasojevic-Tisma, V., Antic, R., Nilsson, R., & Rutqvist, L. E. (2011). Randomized, placebo-controlled, double-blind trial of Swedish snus for smoking reduction and cessation. Harm Reduction Journal, 8, 25.CrossRefGoogle ScholarPubMed
Katz, D., Baptista, J., Azen, S. P., & Pike, M. C. (1978). Obtaining confidence intervals for the risk ratio in cohort studies. Biometrics, 34, 469474.CrossRefGoogle Scholar
Lee, P. N. (2011). Summary of the epidemiological evidence relating snus to health. Regulatory Toxicology and Pharmacology: RTP, 59, 197214.CrossRefGoogle ScholarPubMed
Lee, P. N., & Hamling, J. S. (2009). Systematic review of the relation between smokeless tobacco and cancer in Europe and North America. BMC Medicine, 7, 36.Google Scholar
Liberati, A., Altman, D. G., Tetzlaff, J., Mulrow, C., Gøtzsche, P. C., Ioannidis, J. P. A., Clarke, M., & Moher, D. (2009). The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate healthcare interventions: explanation and elaboration. BMJ, 339, b2700.Google Scholar
Lund, K. E., McNeill, A., & Scheffels, J. (2010). The use of snus for quitting smoking compared with medicinal products. Nicotine & Tobacco Research, 12, 817822.Google Scholar
Pisinger, C., & Godtfredsen, N. S. (2007). Is there a health benefit of reduced tobacco consumption? A systematic review. Nicotine & Tobacco Research, 9, 631646.Google Scholar
Ramström, L. M., & Foulds, J. (2006). Role of snus in initiation and cessation of tobacco smoking in Sweden. Tobacco Control, 15, 210214.Google Scholar
Rodu, B., & Cole, P. (2004). The burden of mortality from smoking: comparing Sweden with other countries in the European Union. European Journal of Epidemiology, 19, 129131.Google Scholar
Rutqvist, L. E., Curvall, M., Hassler, T., Ringberger, T., & Wahlberg, I. (2011). Swedish snus and the GothiaTek® standard. Harm Reduction Journal, 8, 11.CrossRefGoogle ScholarPubMed
Sæterdal, I., Harboe, I., Ringerike, T., & Klemp, M. (2012). Snus som røykeavvenningsmiddel - systematisk litteratursøk med sortering. Notat 2012. Oslo: Nasjonalt kunnskapssenter for helsetjenesten. http://www.kunnskapssenteret.no/PublikasjonerGoogle Scholar
Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR). (2008, (Accessed Oct 2010)). Health effects of smokeless tobacco products. Brussels: European Commission, Health & Consumer Protection Directorate-General. http://ec.europa.eu/health/ph_risk/committees/04_scenihr/docs/scenihr_o_013.pdfGoogle Scholar
Wikström, A.-K., Cnattingius, S., Galanti, M. R., Kieler, H., & Stephansson, O. (2010a). Effect of Swedish snuff (snus) on preterm birth. BJOG: an International Journal of Obstetrics and Gynaecology, 117, 10051010.Google Scholar
Wikström, A. K., Cnattingius, S., & Stephansson, O. (2010b). Maternal use of Swedish snuff (snus) and risk of stillbirth. Epidemiology, 21, 772778.Google Scholar