Electronic cigarette use in China: Awareness, prevalence and regulation.

E-cigarettes were invented in China, and most of the world's e-cigarettes have been produced in China. However, awareness and use of e-cigarettes in China are lower than in Europe and America. Against the backdrop of the increasing use of e-cigarettes, the supervision of e-cigarettes in China has been almost non-existent.A literature search was carried out in five popular Chinese and English databases. These databases were PubMed, EMBASE, the Cochrane Library, China national knowledge infrastructure (CNKI), and Wan-fang database.Twenty-one studies were identified, and a comprehensive analysis of e-cigarette awareness ratio was conducted for different regions of China and according to gender, age group, and smoking status. We also examined e-cigarette use and associated risk factors, and the relationship between e-cigarette use and smoking cessation. In 2015, the prevalence of 'ever use' and 'current use' of e-cigarettes in China were 3.1% and 0.5%, respectively. The review indicates that the awareness ratio of e-cigarettes was about 66% in Hong Kong, whereas the ratio for Tianjin was lower (43.6%). Online sales were the main channel for selling e-cigarettes to 80% of the users. Awareness of e-cigarettes has been increasing in China. Awareness was higher in men compared to women in all age groups. Nevertheless, e-cigarette use in China was lower than in developed countries. E-cigarette users were more likely to try to quit smoking, but the relationship between e-cigarette use and smoking cessation is still unclear. Governance is necessary for e-cigarette use and marketing effort.This study investigated the awareness and use of e-cigarettes in China and the existing regulations for e-cigarette use and marketing. The lack of regulations for e-cigarette use and the unrestricted practice encourage the increase in adoption of e-cigarettes and misconceptions of the benefits of using e-cigarettes. Hence, it is crucial that the government of China prioritize the establishment and implementation of regulations for e-cigarette use and marketing.