Assessing the effect of nicotine reduction on ENDS user's addiction and exposures

项目摘要 电子尼古丁输送系统（ENDS或电子烟）的使用已达到流行水平， 美国的年轻人（US）。ENDS会释放出有毒物质，包括尼古丁， 大脑发育，导致依赖性和吸烟开始的风险增加。证据 表明使用ENDS的年轻人可能会加速使用并成为尼古丁依赖者。一些 年轻人中最流行的ENDS（例如含有5%尼古丁液体的JUUL）在一个药筒中提供尼古丁 剂量等于一整包香烟，许多用户不知道这种实质性的接触， 成瘾的相关风险。另一方面，美国食品和药物管理局已考虑减少尼古丁（NR）， 美国食品药品监督管理局（FDA）作为一个重要的战略，以限制烟草制品的成瘾性和使用。 既然FDA根据“推定规则”对ENDS进行了监管，那么可以考虑这样的策略。 新兴烟草产品。然而，我们仍然缺乏证据表明一系列NR水平对 在使用轨迹的不同阶段结束用户。使用临床和分析实验室方法，我们计划比较 在5%的尼古丁ENDS使用者中，部分（3%）或全部（无尼古丁，0%）NR对使用者依赖性的影响， 满意度、临床（例如BP、血氧测定、肺功能、症状）、吸烟行为和毒物暴露。 我们将招募当前ENDS用户（n=120; 21-35岁），用于3X 2X2受试者间交叉实验室 study.由于NR对ENDS使用者的影响可能会因ENDS使用的频率和阶段而异，我们将 研究高频率与低频率使用者的NR效应（使用≥ 20天与< 20天/过去一个月）。因此，3 尼古丁条件（5%、3%、0%）× 2次（术前、术后）是受试者内因素，而使用频率 是受试者之间的因素。我们假设NR将与较低的满意度，退出， 抑制，并打算使用，这样的效果将更明显，在整体相比，部分 NR和之间的高频率用户相比。这些研究旨在回答3个主要的监管问题。 问题：1）NR是一个有希望的监管选择，以减少ENDS成瘾和使用; 2）效果如何 部分NR与总NR对代偿性抽吸和暴露于尼古丁和呼吸道毒物的影响，以及3） 是NR对ENDS使用者在不同使用阶段的影响。结合起来，这些研究将提供直接和 关于NR法规限制ENDS成瘾性和使用的潜力的标准化证据， 帮助预测NR对ENDS使用者暴露于有害毒物的任何潜在副作用。

PROJECT SUMMARY The use of electronic nicotine delivery systems (ENDS or e-cigarettes) has reached epidemic levels among young people in the United States (US). ENDS emit toxic substances, including nicotine that irreversibly affects the developing brain and leads to dependence and increased risk of cigarette smoking initiation. Evidence indicates that young people using ENDS are likely to accelerate use and become nicotine dependent. Some of the most popular ENDS among youth (e.g. JUUL with 5% nicotine liquid) deliver in one cartridge a nicotine dose equal to an entire pack of cigarettes, and many users are unaware of this substantial exposure and the related risk of addiction. On the other hand, nicotine reduction (NR) has been considered by the US Food and Drug Administration (FDA) as an important strategy to limit the addictiveness and use of tobacco products. Now that the FDA regulates ENDS under the “deeming rule”, such a strategy can be considered for these emerging tobacco products. However, we still lack evidence on the expected effects of a range of NR levels on ENDS users at different stages of use trajectory. Using clinical and analytical lab methods we plan to compare among 5% nicotine ENDS users the effect of partial (3%) or total (nicotine-free, 0%) NR on users' dependence, satisfaction, clinical (e.g. BP, oximetry, lung functions, symptoms), puffing behavior, and exposure to toxicants. We will recruit current ENDS users (n=120; 21-35 yrs), for a 3X2X2 within-between subject crossover lab study. Because the effect of NR on ENDS users will likely vary by frequency and stage of ENDS use, we will study NR effects in high vs. low-frequency users (use on ≥ 20 vs. < 20 days/past month). Therefore, the 3 nicotine conditions (5%, 3%, 0%) x 2 times (pre-post) are the within-subject factors, while the frequency of use is the between-subject factor. We hypothesize that NR will be associated with less satisfaction, withdrawal suppression, and intention to use and that such an effect will be more pronounced in total compared to partial NR and among high compared to low-frequency users. The proposed studies aim to answer 3 main regulatory questions: 1) is NR a promising regulatory option to reduce ENDS addictiveness and use; 2) what is the effect of partial vs. total NR on compensatory puffing and exposure to nicotine and respiratory toxicants, and 3) what is the effect of NR on ENDS users at different stages of their use. Combined, these studies will give direct and standardized evidence on the potential of NR regulations to limit the addictiveness and use of ENDS, and to help predict any potential side effects of NR on ENDS users' exposure to harmful toxicants.