This is the first article published on the status of youth smoking since the implementation of smoke-free legislation in Shenzhen. In the past, Shenzhen's tobacco control efforts were primarily aimed at addressing the adult tobacco epidemic, on the basis of which numerous studies have been conducted [16–18]. Developing sustained and well-established monitoring strategies can contribute to creating effective policies and measures for adolescents that can significantly reduce adolescent smoking rates.
According to our study, the overall current smoking rate among adolescents was 2.3% in Shenzhen, with boys (3.4%) significantly higher than girls (1.0%). There was a positive correlation between adolescent current smoking and their age, with the lowest rates in groups younger than or equal to age 13 (0.7%) and the highest rates in groups older than age 16 (4.7%). The current smoking rate also varies greatly by school type, with the highest in VSHS at 4.1%, the lowest in JSH at 1.0%, and SHS at 2.7%. The overall current smoking rate was virtually unchanged from the 2012 Shenzhen Youth Tobacco Survey, 2.8% compared to 2.3% [14]. Compared with the 2019 GYTS China survey [13], the overall prevalence of the current smoking rate of adolescents in 2019 was significantly decreased, (2.3% vs 5.9%), with similar patterns in boys currently smoking rates (3.4% vs 9.6%), but little change in current smoking rates among girls (1.0% vs 1.9%). This indicates the need to develop gender-specific tobacco control strategies to prevent female adolescents from smoke initiation, and to assist cessation of smoking female adolescents in the future. And then, our results showed that current smoking rates were both lower in JHS, SHS, and VSHS than in the China GYTS 2019 survey [13], 1.0% vs 3.9%, 2.7% vs 5.6% and 4.1% vs 14.7%, respectively. Moreover, the current smoking rate is lower than in other studies conducted in countries and cities in China. For example, the 2019 National Youth Tobacco Survey (NYTS) [19]showed that 5.1% of boys and 3.4% of girls smoked in the last 30 days, and a cross-sectional survey conducted by Lin zhu et al.[20] suggested that the current smoking rate among adolescents was 4.26% in Fujian Province in 2019. This may be related to the implementation of Shenzhen's 2019 comprehensive smoking control regulations, which is considered to be one of the strictest related laws in China.
In this study, we determined the predictors of current adolescent smoking. Adolescents who were boys or older than aged 16 years were more likely to present smoking status, which is consistent with the findings of Meng Wang et al. for middle and high school students in Zhejiang Province in 2012[21]. Additionally, misconceptions about smoking were positively associated with the risk of smoking among adolescents[22, 23]. Adolescents who perceived smoking as more attractive (OR = 2.094, 95%CI:1.266–3.464) and comfortable in social environments (OR = 4.140, 95%CI:2.583–6.633) were at higher risk of using cigarettes and easier to accept e-cigarettes or other tobacco products[24, 25]. In particular, parents, teachers, and peers contribute strongly to adolescent smoking[26]. Either one (OR = 1.634, 95%CI:1.099–2.428) or both parents smoked (OR = 5.348, 95%CI:2.092–13.672) made adolescents more likely to continue smoking. Parental smoking behaviour and tolerant attitudes towards tobacco use are critical to initiating and maintaining smoking among adolescents[27, 28]. Similar to previous studies[29, 30], adolescents surrounded by smoking friends were more likely to smoke at present. Our study also showed that the association between current student smoking and teacher smoking depended on the extent to which teachers' smoking behaviour was seen. There was no relationship between students smoking and occasionally seeing teachers smoking on campus; this risk was only significant when students noticed teachers smoking almost daily or daily. Teachers can play an essential role in shaping the behaviour of young people[31], as they spend most of their time at school, so Shenzhen implemented a city-wide smoke-free school strategy in 2013, which prohibited teachers from smoking in schools. However, smoking teachers undermines or diminishes the authority of smoke-free regulations. Students observing teachers' smoking behaviour may believe no restrictions exist or that existing regulations are more lenient, eventually inducing and sustaining smoking. Previous studies[22, 23, 32] have confirmed that tobacco advertising and promotion exposure is associated with the likelihood of adolescent initiating smoking.
This study demonstrates that the existing tobacco control strategies and measures in Shenzhen are insufficiently effective in discouraging female students from smoking. Future qualitative interviews with female adolescents may be needed to understand the particularities of this group in the area of tobacco control to implement effective and tailored measures. Targeting parents who smoke and developing school-based cessation or prevention programs in the context of smoke-free schools to decrease the number of adolescent smokers in schools, thus significantly reducing the number of smokers based on peer interaction, could be one of the effective ways to address the adolescent tobacco epidemic in the future.