Nicotine lozenges and behavioural interventions may help smokeless tobacco users to quit.

DATA SOURCES: Cochrane Central Register of Controlled trials (CENTRAL); Medline; Embase; PsycINFO. Additional sources were also searched for early versions of the review: Web of Science, Dissertation Abstracts Online, Scopus, Healthstar, ERIC, National Technical Information Service database and Current Contents.

STUDY SELECTION: 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 (ie nicotine replacement therapy (NRT), bupropion, varenicline) or behavioural, and could be directed at individual ST users or at groups of users.

DATA EXTRACTION AND SYNTHESIS: Two authors independently extracted data about participants, interventions, outcomes and methodological quality. Any discrepancies in extracted data were resolved by consensus. Synthesis followed standard Cochrane methodology.

RESULTS: Thirty-four trials were included, 32 from the USA, one from Sweden and one from Sweden and Norway. Sixteen of the trials assessed pharmacological interventions and 19 assessed behavioural interventions (two studies did both). Varenicline increased ST abstinence rates (risk ratio 1.34, 95% confidence interval (CI) 1.08-1.68). Bupropion did not show a benefit of treatment. Neither nicotine patch nor nicotine gum increased abstinence. Nicotine lozenges did increase tobacco abstinence (RR 1.36, 95% CI 1.17-1.59). Behvaioural interventions resulted in a RR of 1.39 (95% CI 1.25-1.55) for those already motivated to quit and 1.37 (95% CI 1.23-1.53) for anyone.

CONCLUSIONS: Varenicline, nicotine lozenges and behavioural interventions may help ST users to quit. Confidence in results for nicotine lozenges is limited. Confidence in the size of effect from behavioural interventions is limited because the components of behavioural interventions that contribute to their impact are not clear.