Awareness and use of e-cigarettes among urban residents in China.

INTRODUCTION The long-term health effects of e-cigarettes are uncertain, and data on e-cigarette use among Chinese adults are limited. This study examined the prevalence and correlates of e-cigarette awareness and use among urban residents in China. Data came from the China City Adult Tobacco Survey (CCATS), a city-representative household survey conducted using electronic tablets during 2013-2014 in 14 major Chinese cities. METHODS CCATS used multistage geographically clustered samples with standardized survey protocols and questionnaire to ensure data comparability. Overall, 31151 adults completed the survey, with sample size varying from 1977 to 3838 across cities, and survey response rates ranging from 79.8% to 97.5%. Respondents were considered current e-cigarette users if they self-reported using e-cigarettes 'daily' or 'less than daily' at the time of the survey. Descriptive statistics and multivariate logistic regression were conducted. Assessed correlates included: age, education, quit attempts in past 12 months, cigarettes smoked per day, and monthly expenditures on cigarettes. RESULTS Overall, 46.7% of respondents were aware of e-cigarettes, 2.9% ever used, and 0.8% currently used. Most current e-cigarette users (93.0%) also currently smoked tobacco. Among male current tobacco smokers, adjusted odds ratio (AOR) of current e-cigarette use was higher among those aged 15-29 (AOR=2.5; 95% CI: 1.5-4.3) or 30-49 (AOR=1.9; 95% CI: 1.0-3.4) than those >= 50 years; those who attempted to quit in the past 12 months than those who did not (AOR=4.7; 95% CI: 2.2-10.1); those with a college degree (AOR=3.4; 95% CI: 1.9-6.2) or just finished high school (AOR=2.2; 95% CI: 1.2-4.2) than those who did not finish high school; and those who smoked >= 15 cigarettes per day (AOR=2.8; 95% CI: 1.4-5.6) than those who smoked fewer. CONCLUSIONS These findings reveal that during 2013-2014, many urban Chinese adults were aware of e-cigarettes, while use was relatively low and most current users also smoked tobacco. Continued monitoring of e-cigarettes could help inform public health policy, planning, and practice.