Center for Tobacco Control Research and Education, University of California San Francisco, San Francisco, CA, United States.
Division of General Internal Medicine, University of California San Francisco, San Francisco, CA, United States.
JMIR Mhealth Uhealth. 2023 Feb 20;11:e40736. doi: 10.2196/40736.
Co-use of tobacco and cannabis is highly prevalent among young US adults. Same-day co-use of tobacco and cannabis (ie, use of both substances on the same day) may increase the extent of use and negative health consequences among young adults. However, much remains unknown about same-day co-use of tobacco and cannabis, in part due to challenges in measuring this complex behavior. Nuanced understanding of tobacco and cannabis co-use in terms of specific products and intensity (ie, quantity of tobacco and cannabis use within a day) is critical to inform prevention and intervention efforts.
We used a daily-diary data collection method via smartphone to capture occurrence of tobacco and cannabis co-use within a day. We examined (1) whether the same route of administration would facilitate co-use of 2 substances on the same day and (2) whether participants would use more tobacco on a day when they use more cannabis.
This smartphone-based study collected 2891 daily assessments from 147 cigarette smokers (aged 18-26 years, n=76, 51.7% female) during 30 consecutive days. Daily assessments measured type (ie, cigarette, cigarillo, or e-cigarette) and intensity (ie, number of cigarettes or cigarillos smoked or number of times vaping e-cigarettes per day) of tobacco use and type (ie, combustible, vaporized, or edible) and intensity (ie, number of times used per day) of cannabis use. We estimated multilevel models to examine day-level associations between types of cannabis use and each type of tobacco use, as well as day-level associations between intensities of using cannabis and tobacco. All models controlled for demographic covariates, day-level alcohol use, and time effects (ie, study day and weekend vs weekday).
Same-day co-use was reported in 989 of the total 2891 daily assessments (34.2%). Co-use of cigarettes and combustible cannabis (885 of the 2891 daily assessments; 30.6%) was most commonly reported. Participants had higher odds of using cigarettes (adjusted odds ratio [AOR] 1.92, 95% CI 1.31-2.81) and cigarillos (AOR 244.29, 95% CI 35.51-1680.62) on days when they used combustible cannabis. Notably, participants had higher odds of using e-cigarettes on days when they used vaporized cannabis (AOR 23.21, 95% CI 8.66-62.24). Participants reported a greater intensity of using cigarettes (AOR 1.35, 95% CI 1.23-1.48), cigarillos (AOR 2.04, 95% CI 1.70-2.46), and e-cigarettes (AOR 1.48, 95% CI 1.16-1.88) on days when they used more cannabis.
Types and intensities of tobacco and cannabis use within a day among young adult smokers were positively correlated, including co-use of vaporized products. Prevention and intervention efforts should address co-use and pay attention to all forms of use and timeframes of co-use (eg, within a day or at the same time), including co-use of e-cigarettes and vaporized cannabis, to reduce negative health outcomes.
在美国年轻成年人中，同时使用烟草和大麻的情况非常普遍。同日同时使用烟草和大麻（即在同一天使用这两种物质）可能会增加年轻人使用的程度和负面健康后果。然而，由于测量这种复杂行为的挑战，人们对同日同时使用烟草和大麻的情况了解甚少。从具体产品和强度（即在一天内使用的烟草和大麻的数量）方面对烟草和大麻共同使用的细微理解，对于为预防和干预工作提供信息至关重要。
我们使用智能手机的日常日记数据收集方法来捕捉一天内烟草和大麻的共同使用情况。我们研究了（1）是否相同的给药途径会促进同一天使用两种物质，以及（2）参与者在使用更多大麻的日子里是否会使用更多的烟草。
这项基于智能手机的研究在 30 天内从 147 名成年吸烟者（年龄 18-26 岁，n=76，51.7%为女性）中收集了 2891 项日常评估。每天的评估测量了烟草使用的类型（即香烟、小雪茄或电子烟）和强度（即每天吸烟或雪茄的数量或电子烟使用的次数）以及大麻使用的类型（即可燃、汽化或可食用）和强度（即每天使用的次数）。我们估计了多层次模型，以检查大麻使用类型与每种烟草使用类型之间的日水平关联，以及大麻和烟草使用强度之间的日水平关联。所有模型均控制了人口统计学协变量、日水平酒精使用情况和时间效应（即研究日和周末与工作日）。
在总共 2891 项日常评估中，有 989 项（34.2%）报告了同日共同使用。最常见的是同时使用香烟和可燃大麻（2891 项日常评估中的 885 项；30.6%）。与使用可燃大麻的日子相比，参与者使用香烟（调整后的优势比[OR]1.92，95%置信区间[CI]1.31-2.81）和小雪茄（OR 244.29，95%CI 35.51-1680.62）的可能性更高。值得注意的是，与使用可燃大麻的日子相比，参与者使用汽化大麻的日子里使用电子烟的可能性更高（OR 23.21，95%CI 8.66-62.24）。参与者报告说，在使用汽化大麻的日子里，他们使用香烟（OR 1.35，95%CI 1.23-1.48）、小雪茄（OR 2.04，95%CI 1.70-2.46）和电子烟（OR 1.48，95%CI 1.16-1.88）的强度更高。
年轻成年吸烟者一天内烟草和大麻使用的类型和强度呈正相关，包括电子烟和汽化大麻的共同使用。预防和干预措施应解决共同使用问题，并注意所有形式的使用和共同使用的时间框架（例如，在一天内或同时），包括电子烟和汽化大麻的共同使用，以减少负面健康后果。
