Department of Health Promotion and Behavioral Sciences, University of Texas Health Science Center, 7000 Fannin St., Houston, TX 77030, USA.
Department of Statistics, Pennsylvania State University, 413 Thomas Building, University Park, PA 16802-2111, USA.
Nicotine Tob Res. 2023 Feb 9;25(3):438-443. doi: 10.1093/ntr/ntac151.
Cross-sectional surveys found behavioral heterogeneity among dual users of combustible and electronic cigarettes. Yet, prior classification did not reflect dynamic interactions between cigarette and e-cigarette consumption, which may reveal changes in product-specific dependence. The contexts of dual use that could inform intervention were also understudied.
This study conducted secondary analysis on 13 waves of data from 227 dual users who participated in a 2-year observational study. The k-means method for joint trajectories of cigarette and e-cigarette consumption was adopted to identify the subtypes of dual users. The time-varying effect model was used to characterize the subtype-specific trajectories of cigarette and e-cigarette dependence. The subtypes were also compared in terms of use contexts.
The four clusters were identified: light dual users, predominant vapers, heavy dual users, and predominant smokers. Although heavy dual users and predominant smokers both smoked heavily at baseline, by maintaining vaping at the weekly to daily level the heavy dual users were able to considerably reduce cigarette use. Yet, the heavy dual users' drop in cigarette dependence was not as dramatic as their drop in cigarette consumption. Predominant vapers appeared to engage in substitution, as they decreased their smoking and increased their e-cigarette dependence. They were also more likely to live in environments with smoking restrictions and report that their use of e-cigarettes reduced cigarette craving and smoking frequency.
Environmental constraints can drive substitution behavior and the substitution behavior is able to be sustained if people find the substitute to be effective.
This study characterizes subtypes of dual users based on the dynamic interactions between cigarette use and e-cigarette use as well as product-specific trajectories of dependence. The subtypes differ in not only sociodemographic characteristics but also contexts of cigarette and e-cigarette use. Higher motivation to use e-cigarettes to quit smoking and less permissive environment for smoking may promote substitution of cigarettes by e-cigarettes.
横断面调查发现，可燃香烟和电子烟的双重使用者之间存在行为异质性。然而，先前的分类并没有反映香烟和电子烟消费之间的动态相互作用，这可能揭示了产品特异性依赖的变化。双重使用的背景也没有得到充分研究，这些背景可能为干预提供信息。
本研究对 227 名参与为期两年观察性研究的双重使用者的 13 波数据进行了二次分析。采用香烟和电子烟消费联合轨迹的 k-均值方法来识别双重使用者的亚类。采用时变效应模型描述香烟和电子烟依赖的亚类特异性轨迹。还根据使用背景比较了亚类。
确定了四个聚类：轻度双重使用者、主要电子烟使用者、重度双重使用者和主要吸烟者。尽管重度双重使用者和主要吸烟者在基线时都吸烟量很大，但通过保持每周至每天的电子烟使用量，重度双重使用者能够大大减少香烟使用量。然而，重度双重使用者香烟依赖的下降并不像香烟消费的下降那样显著。主要电子烟使用者似乎在进行替代，因为他们减少了吸烟量，增加了电子烟依赖。他们也更有可能生活在有吸烟限制的环境中，并报告说使用电子烟减少了对香烟的渴望和吸烟频率。
环境限制可以推动替代行为，如果人们发现替代品有效，替代行为就可以持续。
本研究根据香烟使用和电子烟使用之间的动态相互作用以及产品特异性依赖的轨迹来描述双重使用者的亚类。亚类不仅在社会人口统计学特征上有所不同，而且在香烟和电子烟使用的背景上也有所不同。使用电子烟戒烟的动机更高，对吸烟的环境限制较少，可能会促进用电子烟替代香烟。
