Smokers' Understandings of Addiction to Nicotine and Tobacco: A Systematic Review and Interpretive Synthesis of Quantitative and Qualitative Research.

Background: Despite the centrality of addiction in academic accounts of smoking, there is little research on smokers' beliefs about addiction to smoking, and the role of nicotine in tobacco dependence. Smokers' perspectives on nicotine's role in addiction are important given the increasing prevalence of nontobacco nicotine products such as e-cigarettes. We conducted a systematic review of studies investigating smokers' understandings and lay beliefs about addiction to smoking and nicotine.

Method: We searched PubMed, Embase, CINAHL, and PsycINFO for studies investigating lay beliefs about addiction to smoking. Twenty-two quantitative and 24 qualitative studies met inclusion criteria. Critical interpretive synthesis was used to analyze the results.

Results: Very few studies asked about addiction to nicotine. Quantitative studies that asked about addiction to smoking showed that most smokers believe that cigarettes are an addictive product, and that they are addicted to smoking. Across qualitative studies, nicotine was not often mentioned by participants. Addiction to smoking was most often characterized as a feeling of "need" for cigarettes resulting from an interplay between physical, mental, and social processes. Overall, we found that understandings of smoking were more consistent with the biopsychosocial model of addiction than with more recent models that emphasize the biological aspects of addiction.

Conclusion: Researchers should not treat perceptions of addiction to smoking interchangeably with perceptions of addiction to nicotine. More research on lay beliefs about nicotine is required, particularly considering the increasing use of e-cigarettes and their potential for long-term nicotine maintenance for harm reduction.

Implications: Quantitative studies show that most smokers believe that smoking is addictive and that they are addicted. A feeling of "need" for cigarettes was central to qualitative accounts of addiction, but nicotine was not often discussed. Overall, smokers' understandings of addiction reflect a biopsychosocial model rather than a neurobiological one. Given the growing market for e-cigarettes and therapeutic nicotine, more research is required on lay beliefs about nicotine and addiction.