Randomized, placebo-controlled, double-blind trial of Swedish snus for smoking reduction and cessation

Abstract

BackgroundEpidemiological studies suggest that smokeless tobacco in the form of Swedish snus has been used by many smokers in Scandinavia to quit smoking, but the efficacy of snus has so far not been evaluated in controlled clinical trials.MethodsWe conducted a randomized, double-blind, placebo-controlled, clinical trial aimed at assessing the efficacy of snus to help adult cigarette smokers in Serbia to substantially reduce, and, eventually, completely stop smoking. The study enrolled 319 healthy smokers aged 20-65 years at two occupational health centers in Belgrade, Serbia. Most of them (81%) expressed an interest to quit rather than just reduce their smoking. Study products were used ad libitum throughout the 48-week study period. The main study objective during the first 24 weeks was smoking reduction. The primary end-point was defined as a biologically verified reduction of ≥ 50% in the average number of smoked cigarettes per day during week 21-24 compared to baseline. During week 25-48 participants were actively instructed to stop smoking completely. Outcome measures of biologically verified, complete smoking cessation included 1-week point prevalence rates at clinical visits after 12, 24, 36, and 48 weeks, as well as 4-, 12- and 24-week continued cessation rates at the week 36 and 48 visits.ResultsAt the week 24 visit, the proportion of participants who achieved the protocol definition of a ≥ 50% smoking reduction was similar in the two treatment groups. However, the proportion that reported more extreme reductions (≥ 75%) was statistically significantly higher in the snus group than in the placebo group (p < 0.01). The results for biologically verified complete cessation suggested that participants in the snus group were more likely to quit smoking completely than the controls; the odds ratio (snus versus placebo) for the protocol estimates of cessation varied between 1.9 to 3.4, but these ratios were of borderline significance with p-values ranging from 0.04-0.10. Snus was well tolerated and only 2/158 (1.3%) participants in the snus group discontinued treatment due to an adverse event (in both cases unrelated to snus).ConclusionsSwedish snus could promote smoking cessation among smokers in Serbia, that is, in a cultural setting without traditional use of oral, smokeless tobacco.Trial registrationwww.clinicaltrials.gov, identifier: NCT00601042

A longitudinal, naturalistic study of U.S. smokers' trial and adoption of snus

“…Specifically, individuals instructed to use snus as a means of coping with smoking restrictions reported a reduction in cigarettes per day that was far lower than that reported by those instructed to use snus as a means of smoking reduction (Burris et al, 2014). Furthermore, among smokers who report readiness to quit, snus use shows some efficacy for smoking cessation in randomized clinical trials (Fagerstrom, Rutqvist, & Hughes, 2012; Hatsukami et al, 2015; Joksić, Spasojević-Tišma, Antić, Nilsson, & Rutqvist, 2011; Tønnesen, Mikkelsen, & Bremann, 2008). Consequently, if the tobacco control community chooses to advocate for snus as a means of harm reduction–a topic which is still up for debate (Hatsukami, Ebbert, Feuer, Stepanov, & Hecht, 2007; Hatsukami, Lemmonds, & Tomar, 2004; Levy et al, 2006; O’Connor, 2012; Tomar, 2007)–then messaging around the purpose of snus use must be clear.…”

Snus undermines quit attempts but not abstinence: a randomised clinical trial among US smokers

“…24 Abstinence from cigarettes was nearly identical after 3 months of follow-up (27% vs 25%; independently calculated relative risk=1.1). A separate meta-analysis of only the Fagerström (US) 23 and Joksić (Serbian) 22 RCTs suggested a threefold increase in abstinence in favour of snus. 25 The existing evidence leads to the following inferences: (1) only a small number of randomised trials have tested the impact of snus on smoking behaviour, (2) most studies suggest positive (or sometimes non-significant) effects from snus; no published study has shown negative effects on quitting and (3) all randomised trials, to date, have been abstinence focused, recruiting smokers wanting to quit and providing snus with explicit instructions to do so.…”

“…Abstinence rates were significantly higher at 7 weeks of follow-up (36% vs. 21%; Odds Ratio/OR = 2.1) but did not persist after six months (23% vs. 21%; OR = 1.3). A larger, longer and placebo-controlled study from Serbia found a 3-fold increase in abstinence at 6 months (9.5% vs. 3.7%, Adjusted Odds Ratio/AOR = 2.7), and a nearly 2-fold increase at one year (15.8% vs. 9.3%, AOR = 1.9 [22]. Among smokers wanting to stop smoking, this evidence suggests snus might be an effective substitute for cigarettes.…”

“…Abstinence from cigarettes was nearly identical after 3 months of follow-up (27 vs. 25%; independently calculated Relative Risk = 1.1). A separate meta-analysis of only the Fagerström (US) [23] and Joksić (Serbian) [22] RCTs suggested a three-fold increase in abstinence in favor of snus [25]. …”

“…A larger, longer and placebo-controlled study from Serbia found a threefold increase in abstinence at 6 months (9.5% vs 3.7%, adjusted OR/AOR=2.7), and a nearly twofold increase at 1 year (15.8% vs 9.3%, AOR=1.9). 22 Among smokers wanting to stop smoking, this evidence suggests snus might be an effective substitute for cigarettes. However, no randomised studies have investigated the impact on smoking behaviour of providing snus to smokers in a naturalistic setting among smokers not motivated to quit.…”