Introduction

An increase in electronic cigarette (EC) use among US youth has raised concerns that their use may increase conventional cigarette smoking.

Methods

Repeated cross-sectional data from two large nationally representative samples of US youth were drawn from the National Youth Tobacco Survey (NYTS) and Monitoring the Future (MTF). Students from grade 6–12 of the NYTS (N = 98,454–132,003) and students from grade 12 of the MTF (N = 17,870–30,981) were included in the analyses. Trends in smoking behavior, intention to smoke in the future and perceived smoking harms among youth who do and do not use ECs were estimated from 2014 to 2020 using weighted multinomial logistic regression and predicted marginal probabilities.

Results

The prevalence for regular smoking decreased among youth who regularly use ECs. For example, among regular EC users, smoking prevalence decreased from 27.8% to 6.7% (−21%; 99.67% CI:[−32.3%, −9.9%]) in the NYTS between 2014 and 2020 and from 31.8% to 10.6% (−21.2%, 99.67% CI:[−35.0%, −7.3%]) in the MTF between 2014 and 2018. Intent to smoke in the future and perceiving smoking as harmless decreased or remained unchanged during the same period. For example, among regular EC users, there was no significant change in intention to smoke next year in the NYTS between 2014 and 2018; intention to smoke in the next 5 years decreased significantly from 30.7% to 11.2% (−19.5%, 99.67% CI:[−37.7%, −1.3%]) in the MTF.

Conclusions

In two national samples of US youth, smoking prevalence declined by a sizeable relative percentage. Intent to smoke in the future and harm perceptions of smoking declined or remained unchanged while EC use increased. Results provide little evidence that EC use has increased conventional cigarette smoking among youth.

中文翻译：

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2014 年至 2020 年期间，美国青少年电子烟使用的增加是否改变了传统的吸烟行为、未来的吸烟意图和感知的吸烟危害？

介绍

美国青少年电子烟 (EC) 使用的增加引起了人们的担忧，即他们的使用可能会增加传统香烟的吸烟率。

方法

来自全国青年烟草调查 (NYTS) 和监测未来 (MTF) 的两个具有全国代表性的大型美国青年样本的重复横断面数据。NYTS 6-12 年级的学生 ( N  = 98,454-132,003) 和 MTF 12 年级的学生 ( N  = 17,870-30,981) 被纳入分析。使用加权多项逻辑回归和预测的边际概率估计了 2014 年至 2020 年间使用和不使用 ECs 的青少年的吸烟行为趋势、未来吸烟意图和感知的吸烟危害。

结果

经常使用电子烟的青少年的经常吸烟率下降。例如，在常规 EC 用户中，2014 年至 2020 年 NYTS 的吸烟流行率从 27.8% 降至 6.7%（-21%；99.67% CI：[-32.3%，-9.9%]），并从 31.8% 降至 10.6% (-21.2%, 99.67% CI:[-35.0%, -7.3%]) 在 2014 年至 2018 年间的 MTF 中。在同一时期，未来吸烟的意图和认为吸烟无害的意愿下降或保持不变。例如，在常规 EC 用户中，2014 年至 2018 年 NYTS 明年的吸烟意向没有显着变化；在 MTF 中，未来 5 年的吸烟意向从 30.7% 显着下降到 11.2%（-19.5%，99.67% CI：[-37.7%，-1.3%]）。

结论

在美国青年的两个全国样本中，吸烟率下降了相当大的相对百分比。未来吸烟的意图和对吸烟危害的看法下降或保持不变，而 EC 的使用增加。结果几乎没有证据表明 EC 的使用增加了年轻人的传统吸烟率。