title: Snus undermines quit attempts but not abstinence: a randomised clinical trial among US smokers.
abstract: Observational studies and a few clinical trials suggest that use of low nitrosamine smokeless tobacco (snus) can facilitate smoking cessation. To better understand the real-world impact of snus on smoking behaviour, a large-scale, long-term clinical trial of naturalistic snus use among smokers is needed.
  
  
  
  A nationwide clinical trial compared abstinence outcomes among smokers who were randomised to receive free samples of snus versus not. Participants (N=1236) were recruited throughout the US and assessed for 1 year following a 6-week naturalistic sampling period, with high retention throughout. Primary outcomes included self-reported quit attempts, floating abstinence (any 7-day period of non-smoking) and 7-day point-prevalence abstinence at 6 months and 12 months. Secondary outcomes were changes in smoking, motivation and confidence to quit and adverse events. No tobacco industry support was provided.
  
  
  
  Within snus group, 82% used at least once, and 16% were using regularly at end of sampling period. Compared to control participants, smokers in the snus group were less likely to make any quit attempt (RR=0.83; 95% CI 0.70 to 1.00), and any 24 h quit attempt (RR=0.77; 95% CI 0.63 to 0.95). There were no group differences on any measure of abstinence.
  
  
  
  Provision of snus in a naturalistic context resulted in minimal uptake, and as a whole, undermined quit attempts and did not increase smoking abstinence. Results do not support the unguided, free provision of snus among smokers not motivated to quit as a means to facilitate quit attempts.
  
  
  
  NCT01509586, Results.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina (MUSC), Charleston, South Carolina, USA.|Department of Public Health Sciences, MUSC, Charleston, South Carolina, USA.|Hollings Cancer Center, MUSC, Charleston, South Carolina, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Carpenter
authors.affiliation: Department of Public Health Sciences, MUSC, Charleston, South Carolina, USA.
authors.forename: Amy E
authors.initials: AE
authors.lastname: Wahlquist
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina (MUSC), Charleston, South Carolina, USA.|[Current address] Department of Psychology & Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA.
authors.forename: Jessica L
authors.initials: JL
authors.lastname: Burris
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina (MUSC), Charleston, South Carolina, USA.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Gray
authors.affiliation: Department of Public Health Sciences, MUSC, Charleston, South Carolina, USA.|Hollings Cancer Center, MUSC, Charleston, South Carolina, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Garrett-Mayer
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina (MUSC), Charleston, South Carolina, USA.|Department of Public Health Sciences, MUSC, Charleston, South Carolina, USA.|Hollings Cancer Center, MUSC, Charleston, South Carolina, USA.
authors.forename: K Michael
authors.initials: KM
authors.lastname: Cummings
authors.affiliation: Department of Public Health Sciences, MUSC, Charleston, South Carolina, USA.|Hollings Cancer Center, MUSC, Charleston, South Carolina, USA.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Alberg
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009042:Motivation; D000074285:Smokers / Q000523:psychology / Q000706:statistics & numerical data*; D012907:Smoking / Q000453:epidemiology* / Q000523:psychology; D016540:Smoking Cessation / Q000523:psychology / Q000706:statistics & numerical data*; D013997:Time Factors; D014030:Tobacco, Smokeless; D014481:United States
keywords: Cessation; Harm Reduction; Non-cigarette tobacco products