Examining the Transitions Between Cigarette and Smokeless Tobacco Product Use in the United States Using the 2002-2003 and 2010-2011 Longitudinal Cohorts.

Introduction: Smokeless tobacco (SLT) use in the United States has remained constant or even increased slightly in recent years, whereas smoking has continuously decreased. Characterization of transitions between tobacco products is critical to understand the reasons behind the continuing use of smokeless tobacco.
Methods: Two longitudinal cohorts of Tobacco Use Supplement of the Current Population Survey (TUS-CPS), 2002-2003 (n = 14996) and 2010-2011 (n = 18226), were used to examine transitions between cigarette and SLT use over 1-year periods. Weighted population percentages of four use categories (exclusive cigarette use, exclusive SLT use, dual use, and neither) were calculated for different demographic groups. Transition between use categories and quit rates by product were calculated for each cohort.
Results: Relative to 2002-2003, smoking quit rates of male exclusive smokers significantly increased in 2010-2011 (11.6% vs. 24.4%, p < .0001), but the corresponding SLT use quit rates remained stable (41.3% vs. 40.0%, p = .87). Similar patterns were found in females with smoking quit rates increasing considerably (12.3% vs. 24.2%, p < .0001). Smoking quit rates increased in most sociodemographic groups analyzed. Male SLT use quit rates were significantly lower in SLT exclusive users than in dual users in the 2010-2011 cohort (40.0% vs. 62.2%; p = .04), but smoking quit rates in exclusive smokers and in dual users were roughly equivalent (24.4% vs. 29.5%, p = .68). Conclusions: Although smoking quit rates doubled overall and increased in most sociodemographic groups, SLT quit rates remained constant with little transition between products. Longer-term prospective data examining polytobacco use are needed to better understand transitions between tobacco products. Implications: This study uses two longitudinal surveys to investigate changes in switching behaviors between tobacco products. We found that quit rates of self-reported smoking doubled between 2002-2003 and 2010-2011 in most sociodemographic groups in the United States, whereas in contrast quit rates of self-reported Smokeless Tobacco (SLT) use remained roughly constant. This explains in part the opposing trends of tobacco use by product in the United States, with smoking continuing its decrease, whereas SLT use remains constant. Moreover, smokers were unlikely to switch to other forms of tobacco compared to SLT users. Lastly, smoking cessation for dual users was not significantly different from that of exclusive smokers. Understanding transitions between smoking and SLT use is critical to assess the potential long-term impact of SLT use, and potentially that of other alternative tobacco products, on tobacco-related health outcomes.