How Widespread is the Use of E-Cigarettes Among Adults in the United States Who Have Never Smoked? A Tale of Three Studies.

Background: Whilst e-cigarettes are a less harmful means of consuming nicotine than combustible cigarettes, concerns have been expressed about their use by adults who have never smoked (ANS). It is important to quantify the prevalence of e-cigarette use and to understand patterns of use among ANS to effectively guide public health policy and regulatory decisions.

Methods: The prevalence and patterns of e-cigarette use among ANS were estimated drawing upon data from three national studies in the United States; Population Assessment of Tobacco and Health Study (n = 29,780); the Tobacco Product Prevalence Study (n = 6,428); and the National Health Interview Survey (n = 27,651).

Results: An estimated 5.0 million (5.5%) to 18.6 million (11.1%) ANS have tried e-cigarettes and most of this use is experimental. An estimated 1.5 million (1.6%) to 4.8 million (2.9%) ANS currently use e-cigarettes, and current use is primarily infrequent. However, an estimated 0.5 million (0.5%) to 2.2 million (1.3%) ANS use e-cigarettes frequently. Prevalence of e-cigarette use is highest among younger (18-24 years) ANS.

Conclusions: E-cigarettes are intended to be used by adults who are currently smoking combustible cigarettes as a means of quitting combustible cigarette use or substantially reducing the number of cigarettes smoked.Therefore ANS are an unintended user population. The public health impact associated with e-cigarette use by ANS depends on whether these adults are using e-cigarettes to displace combustible cigarette use (harm avoidance) or whether they would otherwise not have initiated nicotine use if e-cigarettes were not available (harm exposure).