Introduction

Electronic cigarette (e-cigarette) use among adolescents is associated with increased risk of subsequent cigarette smoking initiation in observational research. However, the existing research was not designed to answer causal questions about whether adolescent e-cigarette users would have initiated cigarette smoking if they had never used e-cigarettes. The current study used a causal inference framework to identify whether male adolescent e-cigarette users were at increased risk of initiating cigarette smoking and smokeless tobacco (SLT) use, compared to similar boys who had never used e-cigarettes.

Methods

Boys from urban and Appalachian Ohio (N = 1220; ages 11–16 years at enrollment) reported use of e-cigarettes, cigarettes, and SLT at baseline and every six months for two years. A propensity score matching design was implemented, matching one e-cigarette user to two similar e-cigarette non-users. This analysis was completed in 25 multiple imputed datasets to account for missing data. Risk ratios (RRs) comparing risk of initiating cigarettes and SLT for e-cigarette users and nonusers were estimated.

Results

Compared to non-users, e-cigarette users were more than twice as likely to later initiate both cigarette smoking (RR = 2.71; 95% CI: 1.89, 3.87) and SLT (RR = 2.42; 95% CI: 1.73, 3.38). They were also more likely to become current (i.e., past 30-day) cigarette smokers (RR = 2.20; 95% CI: 1.33, 3.64) and SLT users (RR = 1.64; 95% CI: 1.01, 2.64).

Conclusions

Adolescent boys who used e-cigarettes had increased risk of later initiating traditional tobacco products when compared to similar boys who had never used e-cigarettes.

中文翻译：

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青少年男孩的电子烟使用与卷烟和无烟烟草使用风险：倾向评分匹配分析

介绍

在观察性研究中，青少年使用电子烟（电子烟）与随后开始吸烟的风险增加有关。然而，现有的研究并非旨在回答有关青少年电子烟使用者如果从未使用过电子烟是否会开始吸烟的因果问题。目前的研究使用因果推理框架来确定与从未使用过电子烟的类似男孩相比，男性青少年电子烟使用者开始吸烟和无烟烟草 (SLT) 使用的风险是否增加。

方法

来自俄亥俄州城市和阿巴拉契亚山脉的男孩（N = 1220；入学时年龄为 11-16 岁）报告在基线和两年内每六个月使用电子烟、香烟和 SLT。实施了倾向得分匹配设计，将一名电子烟用户与两名类似的电子烟非用户进行匹配。该分析是在 25 个多重估算数据集中完成的，以解决缺失数据的问题。比较了电子烟使用者和非使用者开始卷烟和 SLT 的风险的风险比 (RR)。

结果

与非使用者相比，电子烟使用者以后开始吸烟（RR = 2.71；95% CI：1.89, 3.87）和 SLT（RR = 2.42；95% CI：1.73, 3.38）的可能性高出两倍以上. 他们也更有可能成为当前（即过去 30 天）吸烟者（RR = 2.20；95% CI：1.33, 3.64）和无烟烟草使用者（RR = 1.64；95% CI：1.01, 2.64）。

结论

与从未使用过电子烟的类似男孩相比，使用电子烟的青少年男孩后来开始使用传统烟草产品的风险增加。