Nardone Natalie, Donny Eric C, Hatsukami Dorothy K, Koopmeiners Joseph S, Murphy Sharon E, Strasser Andrew A, Tidey Jennifer W, Vandrey Ryan, Benowitz Neal L
University of California, San Francisco, Department of Medicine, San Francisco, CA, USA.
University of Pittsburgh, Department of Psychology, Pittsburgh, PA, USA.
Addiction. 2016 Dec;111(12):2208-2216. doi: 10.1111/add.13519. Epub 2016 Aug 1.
Clinical trials on the impact and safety of reduced nicotine content cigarettes (RNCs) are ongoing, and an important methodological concern is participant compliance with smoking only RNCs. Our aims were to measure non-compliance biochemically with urine cotinine (COT) and total nicotine equivalents (TNEs), compare with self-reported non-compliance and identify associated covariates.
Secondary analysis of a double-blind, parallel, randomized clinical trial.
Research centers from the United States, enrolling participants from June 2013 to July 2014.
Volunteer sample of 242 participants (55% Caucasian), average age of 41.2 years, smoking at least five cigarettes per day (CPD).
Smoking very low nicotine cigarettes (VLNCs; 0.4 mg nicotine/g tobacco) for 6 weeks.
The primary outcome was biochemically verified non-compliance, measured as thresholds of COT/CPD and TNE/CPD ratios, considering changes in nicotine content from conventional levels to VLNCs, and as an absolute threshold of week 6 TNEs. Self-reported non-compliance was measured via daily phone calls. Key predictors included age, sex, race, menthol preference, nicotine metabolite ratio, time to first cigarette, dependence, CPD, TNEs, tar level and cigarette evaluation.
Estimates of non-compliance with smoking the VLNCs exclusively include: the biochemical ratios (both 78%), the week 6 TNE threshold (76%) and self-report (39%). Of the key covariates, age, dependence and cigarette evaluations of satisfaction were significant; for age, younger participants more likely to be non-compliant [P = 0.01; odds ratio (OR) = 0.98, 95% confidence interval (CI) = 0.96-0.99]. Dependence was associated significantly with self-reported non-compliance (P = 0.01; OR = 1.28, 95% CI = 1.06-1.55). Cigarette evaluations of satisfaction were associated significantly with non-compliance (P = 0.001; OR = 0.71, 95% CI = 0.61-0.82).
Among smokers volunteering to smoke only very low nicotine cigarettes for 6 weeks, non-compliance was common and biochemical assessments detected more cases of non-compliance than self-report. Despite high levels of non-compliance, smokers reduced their intake of nicotine by an average of 60%.
关于降低尼古丁含量香烟（RNCs）的影响及安全性的临床试验正在进行中，一个重要的方法学问题是参与者是否仅吸食RNCs。我们的目的是通过尿可替宁（COT）和总尼古丁当量（TNEs）进行生化测量来评估不依从情况，与自我报告的不依从情况进行比较，并确定相关的协变量。
一项双盲、平行、随机临床试验的二次分析。
来自美国的研究中心，于2013年6月至2014年7月招募参与者。
242名参与者的志愿者样本（55%为白种人），平均年龄41.2岁，每天至少吸食5支香烟（CPD）。
吸食极低尼古丁香烟（VLNCs；每克烟草含0.4毫克尼古丁），持续6周。
主要结局是经生化验证的不依从情况，通过COT/CPD和TNE/CPD比值的阈值来衡量，并考虑尼古丁含量从传统水平到VLNCs的变化，以及第6周TNEs的绝对阈值。自我报告的不依从情况通过每日电话进行测量。关键预测因素包括年龄、性别、种族、薄荷醇偏好、尼古丁代谢物比值、吸第一支烟的时间、烟瘾、CPD、TNEs、焦油水平和香烟评价。
仅吸食VLNCs的不依从情况估计包括：生化比值（均为78%）、第6周TNE阈值（76%）和自我报告（39%）。在关键协变量中，年龄、烟瘾和对香烟满意度评价具有显著意义；就年龄而言，年轻参与者更有可能不依从[P = 0.01；比值比（OR）= 0.98，95%置信区间（CI）= 0.96 - 0.99]。烟瘾与自我报告的不依从情况显著相关（P = 0.01；OR = 1.28，95% CI = 1.06 - 1.55）。对香烟满意度评价与不依从情况显著相关（P = 0.001；OR = 0.71，95% CI = 0.61 - 0.82）。
在自愿仅吸食极低尼古丁香烟6周的吸烟者中，不依从情况很常见，生化评估发现的不依从案例比自我报告更多。尽管不依从情况严重，但吸烟者的尼古丁摄入量平均减少了60%。
