TY - JOUR
T1 - Estimations and predictors of non-compliance in switchers to reduced nicotine content cigarettes
AU - Nardone, Natalie
AU - Donny, Eric C.
AU - Hatsukami, Dorothy K.
AU - Koopmeiners, Joseph S.
AU - Murphy, Sharon E.
AU - Strasser, Andrew A.
AU - Tidey, Jennifer W.
AU - Vandrey, Ryan
AU - Benowitz, Neal L.
N1 - Publisher Copyright:
© 2016 Society for the Study of Addiction
PY - 2016/12/1
Y1 - 2016/12/1
N2 - Background and Aims: 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. Design: Secondary analysis of a double-blind, parallel, randomized clinical trial. Setting: Research centers from the United States, enrolling participants from June 2013 to July 2014. Participants: Volunteer sample of 242 participants (55% Caucasian), average age of 41.2 years, smoking at least five cigarettes per day (CPD). Intervention: Smoking very low nicotine cigarettes (VLNCs; 0.4 mg nicotine/g tobacco) for 6 weeks. Measurements: 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. Findings: 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). Conclusions: 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%.
AB - Background and Aims: 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. Design: Secondary analysis of a double-blind, parallel, randomized clinical trial. Setting: Research centers from the United States, enrolling participants from June 2013 to July 2014. Participants: Volunteer sample of 242 participants (55% Caucasian), average age of 41.2 years, smoking at least five cigarettes per day (CPD). Intervention: Smoking very low nicotine cigarettes (VLNCs; 0.4 mg nicotine/g tobacco) for 6 weeks. Measurements: 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. Findings: 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). Conclusions: 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%.
KW - Biomarkers
KW - cigarette smoking
KW - cotinine
KW - nicotine reduction
KW - reduced nicotine content cigarettes
KW - total nicotine equivalents
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U2 - 10.1111/add.13519
DO - 10.1111/add.13519
M3 - Article
C2 - 27367436
AN - SCOPUS:84979740750
SN - 0965-2140
VL - 111
SP - 2208
EP - 2216
JO - Addiction
JF - Addiction
IS - 12
ER -