Article Text
Abstract
Background E-cigarette use remains a controversial topic, yet there is a consensus that use in children and adolescents should be avoided. The extent of e-cigarette use among youth in the UK and the potential for e-cigarettes to be a gateway to cigarette smoking is of particular concern. Multistate transition models can be used to examine the complex relationships between different nicotine-products, however this methodology has yet to be applied to UK youth. The UK provides an important case study for e-cigarette policy as it has relatively high levels of use with comparatively permissive e-cigarette policies. Therefore, this study examined transitions into and out of nicotine-product use in a representative sample of UK youth.
Methods A representative sample of 10,229 participants (10–25 years old) from the UK Household Longitudinal Study (2015–2021) were used. Markov multistate transition probability models were used to examine transitions between four nicotine-product-use states (‘never’, ‘non-current use’, ‘e-cigarette only’ and ‘smoking and dual use’). The likelihood of transitions over time and according to age, sex, ethnicity, and income were estimated.
Results Among participants that had never used nicotine products, most were still non-users a year later (92.9% probability; 95% CI 92.6%, 93.2%); a small proportion transitioned to using e-cigarettes only (4.0%; CI 3.7%, 4.2%); and a small proportion to using cigarettes (2.2%; CI 2.0%, 2.4%). Non-users aged 14–17 years were the most likely to start using a nicotine product. E-cigarette use was less persistent over time than cigarette smoking, with a 59.1% probability (CI 56.9%, 61.0%) of e-cigarette users still using e-cigarettes after one year compared to 73.8% (CI 72.1%, 75.4%) for cigarette smoking. However, there was a 14% probability (CI 13%, 16%) that e-cigarette users went onto smoke cigarettes after one year, rising to 25% (CI 23%, 27%) after three years.
Conclusion This study found that overall transitioning into nicotine-product use was relatively rare. However, if participants did take-up nicotine products, they were more likely to experiment with e-cigarette use than cigarette smoking. E-cigarette use was mostly not persistent over time, although approximately one in four e-cigarette users transitioned to cigarette smoking after three years. These results highlight that greater regulation of e-cigarettes is needed to prevent long-term nicotine product use from becoming established.