Background:
There is paucity of data regarding e-cigarette use in China. Monitoring e-cigarette use is important given the rapid increase of e-cigarette use in some countries. We investigated the prevalence and determinants of e-cigarette use among Chinese male urban tobacco smokers, as most Chinese urban residents who use e-cigarettes are male smokers (~90%).

Methods:
We analyzed data from China City Adult Tobacco Surveys, which were conducted in 14 major Chinese cities individually in 2013-14 with 15,008 males aged ≥15 years. Current e-cigarette users were defined as persons who reported using e-cigarette daily or less than daily at the time of the survey. We calculated the prevalence of e-cigarette use among male current tobacco smokers. Multivariate logistic regression was used to assess determinants of e-cigarette use, including age, education, quit attempts in the past 12 months, cigarettes smoked per day, and monthly expenditure on cigarettes.

Results:
Among urban male current smokers in China, 3.6% were current e-cigarette users. The likelihood of being current e-cigarette users was significantly higher among: smokers aged 15-29 (OR=2.5) or 30-49 (OR=2.1) years than 50+ years; those who attempted to quit than those who made no attempt (OR=4.5); those with ≥college education than those with ≤high school education (OR=2.6); and those who smoked ≥15 cigarettes per day (OR=2.7) than those who smoked 1-14 cigarettes per day (all p< 0.05).

Conclusions:
Among urban male tobacco smokers in China, current e-cigarette use was higher among those who were younger, had more education, attempted to quit smoking in the past year, and smoked more cigarettes per day. Given that e-cigarettes are not currently regulated and often marketed as healthier alternatives to cigarettes in China, continued monitoring of e-cigarette use is important to inform public health policy, planning, and practice.