Smoking status of e-cigarette users

Half (52.7%^a) of ever users and a majority (64.5%^b) of past 30-day users of e-cigarettes were current smokers, suggesting that dual use of cigarettes and e-cigarettes is high. Approximately one in five ever and past 30-day e-cigarette users were former smokers. One-quarter of ever users and 15.5% of recent users of e-cigarettes had never been a smoker, indicating interest among non-smokers (Figure 12.15; Figure 12.16). There were no differences between males and females in the percentages of ever or past 30-day users who were smokers (49.3%^c vs. 58.0%^d and 64.6%^e vs. 64.3%^f, respectively).^170,171

The percentages of ever and past 30-day e-cigarette users who were current smokers were lowest among youth aged 15-19, increasing with age^{172, 173} (Figure 12.17; Figure 12.18). Among youth aged 15-19, never smokers comprised the majority of ever (71.7%^g) and past 30-day (60.5%^h) e-cigarette users; among young adults aged 20-24, never smokers comprised 48.4%ⁱ and 30.6%^j of ever and recent users, respectively. Never smokers comprised 29.8%^k of ever users aged 25-34, but few recent users in this age group. E-cigarette use among never smokers over age 35 was rare. 

95% confidence intervals for in-text estimates 

a: 52.7 [47.3-58.2]
b: 64.5 [55.4-73.6]
c: 49.3 [42.0-56.6]
d: 58.0 [50.3-65.7]
e: 64.6 [53.4-75.9]
f: 64.3 [48.9-79.8]
g: 71.7 [66.3-77.0]
h: 60.5 [51.4-69.6]
i: 48.4 [43.3-53.5]
j: 30.6 [19.5-41.8]
k: 29.8 [18.7-40.8]