Perceived Comparative Harm of Cigarettes and Electronic Nicotine Delivery Systems

Scientific evidence on the health risks associated with using electronic nicotine delivery systems (ENDS) is rapidly evolving. Perceived harm of ENDS is also changing rapidly. The percentage of US adults, including current smokers, who perceive using ENDS as equally or more harmful than smoking cigarettes increased between 2012 and 2015, with rates stable through 2017.¹ Comparative harm perceptions are important factors associated with smokers’ decisions to use ENDS^2,3 and have implications for population health. This study uses data from late 2018 to assess changes in US adults’ comparative harm perceptions of ENDS and cigarettes after a year characterized by intense public debate and regulatory efforts to restrict youth access to ENDS.

This survey study was approved by the institutional review board at Georgia State University with a waiver of informed consent because the study posed minimal risk to participants, data were deidentified, and the KnowledgePanel⁴ invitation to participate in the study contained some elements of informed consent. We followed the American Association for Public Opinion Research (AAPOR) reporting guideline.

Data were obtained from the Tobacco Products and Risk Perceptions Surveys conducted in August through September 2017 and November through December 2018 by the Georgia State University Tobacco Center of Regulatory Science. The Tobacco Products and Risk Perceptions Survey is an annual cross-sectional survey of a probability sample and representative oversample of preidentified cigarette smokers drawn from KnowledgePanel,⁴ a web panel designed to be representative of noninstitutionalized US adults 18 years and older. In total, 5992 US adults completed the 2017 survey (cumulative response rate, 5.8%) and 5989 US adults completed the 2018 survey (cumulative response rate, 6.0%). Study-specific poststratification weights, based on demographic and geographic distributions from the Current Population Surveys as benchmarks for adjustment, were computed using an iterative proportional fitting procedure adjusting for survey nonresponse. Comparative perceived harm of ENDS vs cigarettes was asked of those aware of ENDS and was measured as follows: “Is using electronic vapor products less harmful, about the same, or more harmful than smoking regular cigarettes?” Response options were much less harmful, less harmful, about the same level of harm, more harmful, much more harmful, and I don’t know. Weighted point estimates and 95% CIs were obtained, and differences between 2017 and 2018 data were assessed by χ² tests of association. Data analyses were conducted using SPSS statistical software Complex Samples module version 25 (IBM). P values were 2-sided, and statistical significance was set at less than .05. Analyses were conducted in May and June 2019.

There were 5357 participants (mean [SD] age, 47.5 [17.1] years; 2660 [49.7%] women) in our 2017 sample and 5445 participants (mean [SD] age, 48.0 [17.2] years; 2849 [52.3%] women) in our 2018 sample. After study-specific poststratification weights were included, the 2017 sample included 51.0% women and the 2018 sample included 50.9% women. Between 2017 and 2018, the percentage of US adults who perceived ENDS to be less harmful than cigarettes decreased (29.3% [95% CI, 27.8%-30.7%] vs 25.8% [95% CI, 24.4%-27.2%]), while there was an increase in the proportion of US adults who perceived ENDS to be more harmful (2.4% [95% CI, 2.0%-2.9%] vs 4.4% [95% CI, 3.9%-5.1%]) or much more harmful (1.9% [95% CI, 1.5%-2.5%] vs 3.7% [95% CI, 3.1%-4.4%]) (Table). Between 2017 and 2018, ENDS were increasingly perceived to be much more harmful among current smokers (1.8% [95% CI, 1.1%-2.9%] vs 4.4% [95% CI, 3.1%-6.4%]) and former smokers (1.0% [95% CI, 0.5%-1.9%] vs 3.5% [95% CI, 2.5%-4.8%]). The percentage of adults perceiving ENDS to be equally as harmful as cigarettes also increased from 36.4% (95% CI, 34.9%-38.0%) to 43.0% (95% CI, 41.5%-44.6%), while the percentage of adults uncertain of the comparative harm decreased from 25.3% (95% CI, 24.0%-26.7%) to 19.3% (95% CI, 18.0%-20.5%).

This survey study including data from late 2018, before the reported lung disease outbreak and deaths associated with vaping of 2019,⁵ found an increase in the proportion of US adults who perceived ENDS to be equally or more harmful than cigarettes. Notably, an increase in perceiving ENDS as much more harmful than cigarettes was observed among cigarette smokers, which may influence their decision to try or switch to ENDS use. The increase in perceived risk of ENDS from 2017 to 2018 may be associated with media coverage⁶ and the political and regulatory response to the rise in youth ENDS use in 2018. Given the recent surge in reported cases of lung illness associated with vaping and the rapidly evolving evidence, the extent of public uncertainty about the comparative harm of ENDS and cigarettes may have increased since 2018. A limitation of this study is that perceived harm of ENDS vs cigarettes was measured by a general question that did not describe specific health risks associated with product use. Perceptions of harm pertaining to specific diseases may differ from overall risk perceptions associated with ENDS use. In addition, these data were collected before the current vaping-related illness outbreak, and any resulting changes in perception are not captured by this study. Continued monitoring of comparative risk perceptions is warranted.

Accepted for Publication: September 23, 2019.

Published: November 20, 2019. doi:10.1001/jamanetworkopen.2019.15680

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2019 Nyman AL et al. JAMA Network Open.

Corresponding Author: Amy L. Nyman, MA, School of Public Health, Georgia State University, PO Box 3995, Atlanta, GA 30302 (anyman@gsu.edu).

Author Contributions: Ms Nyman had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: All authors.

Acquisition, analysis, or interpretation of data: Nyman, Huang, Weaver.

Drafting of the manuscript: Nyman.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Nyman.

Obtained funding: Weaver, Eriksen.

Administrative, technical, or material support: Nyman, Huang, Weaver.

Supervision: Huang, Eriksen.

Conflict of Interest Disclosures: None reported.

Funding/Support: This work was supported by the National Institutes of Health (NIH) National Institute on Drug Abuse and the Food and Drug Administration (FDA) Center for Tobacco Products (grant P50DA036128).

Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Disclaimer: The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH or the FDA.

Additional Contributions: David L. Ashley, PhD (Department of Health Policy and Behavioral Sciences, School of Public Health, Georgia State University), provided helpful manuscript review. Dr Ashley was not compensated for this work.