Background

Although many smokers use electronic cigarettes (e-cigarettes) to quit smoking, most continue to smoke while vaping. This dual use might delay cessation and increase toxicant exposure. We aimed to test the efficacy of a self-help intervention designed to help dual users to quit smoking.

Methods

In this three-arm randomised controlled trial we recruited individuals in the USA using Facebook and multimedia advertisements. Included participants were 18 years or older, smoked at least weekly in the preceding year, and vaped at least weekly in the preceding month. We used computer generated randomisation with balanced-permuted blocks (block size 10, with 2-4-4 ratio) to allocate participants to assessment only (ASSESS group), generic smoking cessation self-help booklets (GENERIC group), or booklets targeting dual users (eTARGET group). Individuals in the generic or targeted intervention groups received monthly cessation materials for 18 months, with assessments every 3 months for 24 months. The main outcome was self-reported 7-day point-prevalence smoking abstinence at each assessment point. All randomly allocated participants were included in primary analyses using generalised estimating equations for each of 20 datasets created by multiple imputation. Analysis of the χ²s produced an F test. The trial is registered with ClinicalTrials.gov, NCT02416011, and is now closed.

Findings

Between July 12, 2016, and June 30, 2017, we randomly assigned 2896 dual users (575 to assessment, 1154 to generic intervention, and 1167 to targeted self-help). 7-day point-prevalence smoking abstinence increased from 14% at 3 months to 42% at 24 months (F_7,541·7=67·1, p<0·0001) in the overall sample. Targeted self-help resulted in higher smoking abstinence than did assessment alone throughout the treatment period (F_1,973·8=10·20, p=0·0014 [α=0·017]). The generic intervention group had abstinence rates between those of the assessment and targeted groups, but did not significantly differ from either when adjusted for multiple comparisons (GENERIC vs eTARGET F_1,1102·5=1·79, p=0·18 [α=0·05]; GENERIC vs ASSESS F_1,676·7=4·29, p=0·039 [α=0·025]). Differences between study groups attenuated after the interventions ended.

Interpretation

A targeted self-help intervention with high potential for dissemination could be efficacious in promoting smoking cessation among dual users of combustible cigarettes and e-cigarettes.

Funding

National Institute on Drug Abuse, National Cancer Institute.

中文翻译：

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可燃和电子烟双重使用者的针对性戒烟：一项随机对照试验

背景

尽管许多吸烟者使用电子烟（e-香烟）来戒烟，但大多数人在吸电子烟的同时继续吸烟。这种双重用途可能会延迟戒烟并增加毒物暴露。我们旨在测试旨在帮助双重用户戒烟的自助干预措施的有效性。

方法

在这项三臂随机对照试验中，我们使用 Facebook 和多媒体广告在美国招募了个人。包括的参与者年龄在 18 岁或以上，在前一年至少每周抽一次烟，在前一个月至少每周抽一次电子烟。我们使用带有平衡置换区块（区块大小为 10，比例为 2-4-4）的计算机生成的随机化将参与者分配到仅评估（ASSESS 组）、通用戒烟自助小册子（GENERIC 组）或针对双重用户（eTARGET 组）。通用或目标干预组中的个人在 18 个月内每月收到戒烟材料，在 24 个月内每 3 个月进行一次评估。主要结果是自我报告的每个评估点的 7 天戒烟率。所有随机分配的参与者都包括在主要分析中，使用广义估计方程对通过多重插补创建的 20 个数据集中的每一个进行评估。χ 的分析² s 产生了 F 检验。该试验已在 ClinicalTrials.gov 注册，NCT02416011，现已结束。

发现

2016 年 7 月 12 日至 2017 年 6 月 30 日期间，我们随机分配了 2896 名双重用户（575 名用于评估，1154 名用于一般干预，1167 名用于定向自助）。在整个样本中，7 天戒烟率从 3 个月时的 14% 增加到 24 个月时的 42% ( F _7,541·7 =67·1，p<0·0001)。在整个治疗期间，有针对性的自助比单独评估导致更高的戒烟率（F _1,973·8 =10·20，p=0·0014 [α=0·017]）。通用干预组的戒断率介于评估组和目标组之间，但在进行多重比较调整后与任一组均无显着差异（GENERIC vs eTARGET F _1,1102·5=1·79，p=0·18 [α=0·05]；通用与评估F _1,676·7 =4·29，p=0·039 [α=0·025]）。干预结束后，研究组之间的差异减弱。

解释

具有高传播潜力的有针对性的自助干预可能有效促进可燃卷烟和电子烟双重使用者的戒烟。

资金

国家药物滥用研究所，国家癌症研究所。