Effectiveness of a text-messaging-based smoking cessation intervention (“Happy Quit”) for smoking cessation in China: A randomized controlled trial

BackgroundChina has the highest global prevalence of cigarette smokers, accounting for more than 40% of the total cigarette consumption in the world. Considering the shortage of smoking cessation services in China, and the acceptability, feasibility, and efficacy of mobile-phone-based text messaging interventions for quitting smoking in other countries, we conducted a mobile-phone-based smoking cessation study in China.Methods and findingsWe conducted a randomized controlled trial in China across 30 cities and provinces from August 17, 2016, to May 27, 2017. Adult smokers aged 18 years and older with the intention to quit smoking were recruited and randomized to a 12-week high-frequency messaging (HFM) or low-frequency messaging (LFM) intervention (“Happy Quit”) or to a control group in a 5:2:3 ratio. The control group received only text messages unrelated to quitting. The primary outcome was biochemically verified continuous smoking abstinence at 24 weeks. Secondary outcomes included (1) self-reported 7-day point prevalence of abstinence (i.e., not even a puff of smoke, for the last 7 days) at 1, 4, 8, 12, 16, 20, and 24 weeks; (2) self-reported continuous abstinence at 4, 12, and 24 weeks; and (3) self-reported average number of cigarettes smoked per day. A total of 1,369 participants received 12 weeks of intervention or control text messages with continued follow-up for 12 weeks. The baseline characteristics of participants among the HFM (n = 674), LFM (n = 284), and control (n = 411) groups were similar. The study sample included 1,295 (94.6%) men; participants had a mean age of 38.1 (SD 9.79) years and smoked an average of 20.1 (SD 9.19) cigarettes per day. We included the participants in an intention-to-treat analysis. Biochemically verified continuous smoking abstinence at 24 weeks occurred in 44/674 participants in the HFM group (6.5%), 17/284 participants in the LFM group (6.0%), and 8/411 participants (1.9%) in the control group; participants in both the HFM (odds ratio [OR] = 3.51, 95% CI 1.64–7.55, p 0.001) and the LFM (OR = 3.21, 95% CI 1.36–7.54], p = 0.002) intervention groups were more likely to quit smoking than those in the control group. However, there was no difference in quit rate between the HFM and LFM interventions. We also found that the 7-day point quit rate from week 1 to week 24 ranged from approximately 10% to more than 26% with the intervention and from less than 4% to nearly 12% without the intervention. Those who continued as smokers in the HFM group smoked 1 to 3 fewer cigarettes per day than those in the LFM group over the 24 weeks of trial. Among study limitations, the participants were able to use other smoking cessation services (although very few participants reported using them), cotinine tests can only detect smoking status for a few days, and the proportion of quitters was small.ConclusionsOur findings demonstrate that a mobile-phone-based text messaging intervention (Happy Quit), with either high- or low-frequency messaging, led to smoking cessation in the present study, albeit in a low proportion of smokers, and can therefore be considered for use in large-scale intervention efforts in China. Mobile-phone-based interventions could be paired with other smoking cessation services for treatment-seeking smokers in China.Trial registrationClinicalTrials.gov NCT02693626.【背景】中国是全球吸烟者患病率最高的国家，卷烟消费量占全球总量的40%以上。鉴于中国戒烟服务（smoking cessation services）存在短缺，且其他国家已证实基于手机短信的戒烟干预（mobile-phone-based text messaging interventions for smoking cessation）具备可接受性、可行性与有效性，本研究在中国开展了一项基于手机短信的戒烟研究。 【方法与结果】本研究于2016年8月17日至2017年5月27日在中国30个省市开展随机对照试验（randomized controlled trial）。招募年满18岁、有戒烟意愿的成年吸烟者，按照5:2:3的比例随机分为12周高频短信干预（HFM）组、低频短信干预（LFM）组（干预项目命名为"Happy Quit"）以及对照组。对照组仅接收与戒烟无关的短信。主要结局指标为24周时经生化验证的持续戒烟（continuous smoking abstinence）率。次要结局指标包括：① 分别在第1、4、8、12、16、20、24周时自我报告的7天时点戒烟率（7-day point prevalence of abstinence，即过去7天完全未吸食任何一口烟）；② 第4、12、24周时自我报告的持续戒烟情况；③ 自我报告的日均吸烟量。最终共有1369名受试者完成12周干预或对照短信干预，并完成了后续12周的随访。高频短信组（n=674）、低频短信组（n=284）与对照组（n=411）受试者的基线特征均衡可比。研究样本中男性占比94.6%（1295/1369），受试者平均年龄为38.1岁（标准差（SD）=9.79），日均吸烟量平均为20.1支（SD=9.19）。本研究采用意向性分析（intention-to-treat analysis）进行统计。24周时经生化验证的持续戒烟率：高频短信组为6.5%（44/674），低频短信组为6.0%（17/284），对照组为1.9%（8/411）；与对照组相比，高频短信组（比值比OR=3.51，95%置信区间CI=1.64~7.55，P=0.001）与低频短信组（OR=3.21，95%CI=1.36~7.54，P=0.002）的戒烟成功率均显著更高。但高频与低频短信干预组的戒烟率无显著差异。研究还发现，干预组第1周至24周的7天时点戒烟率介于约10%至26%以上，对照组则介于不足4%至近12%之间。在整个24周试验期间，高频短信组仍在吸烟的受试者日均吸烟量较低频短信组少1~3支。本研究存在以下局限性：受试者可自行使用其他戒烟服务（尽管报告使用的受试者极少）；可替宁检测（cotinine tests）仅能在数天内检测吸烟状态；最终戒烟者的占比仍较低。 【结论】本研究结果显示，基于手机短信的戒烟干预项目"Happy Quit"，无论采用高频还是低频短信模式，均可显著提升戒烟成功率（尽管整体戒烟比例仍偏低），因此可考虑在中国开展大规模戒烟干预项目。基于手机短信的干预可与其他戒烟服务结合，为中国有戒烟需求的吸烟者提供支持。 【试验注册】ClinicalTrials.gov NCT02693626。