Association of quarterly prevalence of e-cigarette use with ever regular smoking among young adults in England: a time-series analysis between 2007 and 2018.

Introduction:
This text presents the results of a time-series analysis examining the association between the prevalence of e-cigarette use and ever regular smoking among young adults in England between 2007 and 2018. The study used ARIMAX models and SVAR models to assess the data. The key points section will summarize the study design and major findings, while the main message will highlight the implications of the results.

Key Points:

* The study used ARIMAX and SVAR models to analyze the association between the prevalence of e-cigarette use and ever regular smoking among young adults in England between 2007 and 2018.
* The ARIMAX models found no significant association between e-cigarette use and ever regular smoking prevalence for the entire sample or for the stratified age groups of 16-17 and 18-24.
* The SVAR models found a small positive association between e-cigarette use and ever regular smoking prevalence among 16-17 year-olds, but this association was not significant in the most direct assessment.
* The SVAR models also found no significant association between e-cigarette use and ever regular smoking prevalence for the entire sample or for the 18-24 age group.
* The study attempted to assess the possible evidence for a gateway effect by looking at the association between e-cigarette use and ever regular smoking prevalence as a measure of smoking uptake.
* The study defined ever regular smoking as those using cigarettes either daily or non-daily, consistent with other youth surveys in the United Kingdom.
* The study found that changes in prevalence of e-cigarette use among 16-24 year-olds in England did not appear to be associated with increases in the uptake of smoking in this age group, but small associations cannot be ruled out, particularly for 16-17 year-olds.

Main Message:
The main message of this study is that there is little evidence to suggest that changes in the prevalence of e-cigarette use among young adults in England are associated with increases in the uptake of smoking. While small associations cannot be ruled out, particularly for 16-17 year-olds, the study provides reassurance that the rise in e-cigarette use is not leading to a significant increase in smoking prevalence. These findings can inform regulatory decisions related to e-cigarette use and smoking prevention policies.

Beard E, Brown J, Shahab L. Association of quarterly prevalence of e-cigarette use with ever regular smoking among young adults in England: a time-series analysis between 2007 and 2018. Addiction (Abingdon, England). 2022;117(8):2283-2293. doi:10.1111/add.15838