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Research on nicotine metabolism has primarily focused on white adults. This study examined associations between nicotine metabolism, tobacco use, and demographic characteristics among Alaska Native adults who smoke cigarettes. Participants (N = 244) were Alaska Native adults who smoked and who provided a plasma sample at baseline (70.1%) or follow-up (29.9%) of a randomized controlled trial of a cardiovascular risk behavior intervention. At baseline, participants self-reported age, sex, Alaska Native heritage, cigarettes per day, time to first cigarette upon wakening, menthol use, perceived difficulty staying quit, tobacco withdrawal symptoms, and past-month tobacco product use, binge drinking, and cannabis use. At 3-, 6-, 12-, and 18-month follow-ups, participants self-reported 7-day point prevalence abstinence from smoking. Height and weight were measured to calculate body mass index (BMI). Participants' nicotine metabolite ratio (NMR), calculated as the ratio of plasma cotinine and trans-3' hydroxycotinine, was log-transformed. The sample (52.0% male, age M = 47.0 years [SD = 13.8], 60.3% of Inupiaq heritage) averaged 12.5 cigarettes per day (SD = 10.5); 64.0% smoked within 30 min of wakening. NMR was not significantly associated with age, sex, Alaska Native heritage, BMI, cigarettes per day, time to first cigarette upon wakening, menthol use, perceived difficulty staying quit, past-month dual tobacco product use, withdrawal symptoms, past-month binge drinking, past-month cannabis use, or abstinence from smoking (all p-values > .050). Characteristics that relate to NMR in Alaska Native adults may differ from those typically identified among white adults. Specifically, results may suggest that Alaska Native adults with slower nicotine metabolism do not titrate their nicotine intake when smoking. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

CYP2A6 activity, phenotyped by the nicotine metabolite ratio (NMR), is a predictor of several smoking behaviors, including cessation and smoking‐related disease risk. The heritability of the NMR is 60–80%, yet weighted genetic risk scores (wGRSs) based on common variants explain only 30–35%. Rare variants (minor allele frequency

Author(s): Beard, Emma; Jackson, Sarah E; Anthenelli, Robert M; Benowitz, Neal L; Aubin, Lisa St; McRae, Thomas; Lawrence, David; Russ, Cristina; Krishen, Alok; Evins, A Eden; West, Robert | Abstract: Background and aimsAnalysed using classical frequentist hypothesis testing with alpha set to 0.05, the Evaluating Adverse Events in a Global Smoking Cessation Study (EAGLES) did not find enough evidence to reject the hypothesis of no difference in neuropsychiatric adverse events (NPSAEs) attributable to varenicline, bupropion, or nicotine patch compared with placebo. This might be because the null hypothesis was true or because the data were insensitive. The present study aimed to test the hypothesis more directly using Bayes factors.DesignEAGLES was a randomised, double-blind, triple-dummy, controlled trial.SettingGlobal (16 countries across five continents), between November 2011 and January 2015.ParticipantsParticipants were smokers with (nn=n4116) and without (nn=n4028) psychiatric disorders.InterventionsVarenicline (1nmg twice daily), bupropion (150nmg twice daily), nicotine patch (21nmg once daily with taper) and matched placebos.MeasurementsThe outcomes included: (i) a composite measure of moderate/severe NPSAEs; and (ii) a composite measure of severe NPSAEs. The relative evidence for there being no difference in NPSAEs versus data insensitivity for the medications was calculated in the full and sub-samples using Bayes factors and corresponding robustness regions.FindingsFor all but two comparisons, Bayes factors were l1/3, indicating moderate to strong evidence for no difference in risk of NPSAEs between active medications and placebo (Bayes factor = 0.02-0.23). In the psychiatric cohort versus placebo, the data were suggestive, but not conclusive of no increase in NPSAEs with varenicline (Bayes factorn=n0.52) and bupropion (Bayes factorn=n0.71). Here, the robustness regions ruled out an≥7% and ≥8% risk increase with varenicline and bupropion, respectively.ConclusionsSecondary analysis of the Evaluating Adverse Events in a Global Smoking Cessation Study trial using Bayes factors provides moderate to strong evidence that use of varenicline, bupropion or nicotine patches for smoking cessation does not increase the risk of neuropsychiatric adverse events relative to use of placebo in smokers without a history of psychiatric disorder. For smokers with a history of psychiatric disorder the evidence also points to no increased risk but with less confidence.

Author(s): Liakoni, Evangelia; Tyndale, Rachel F; Jacob, Peyton; Dempsey, Delia A; Addo, Newton; Benowitz, Neal L | Abstract: ObjectivesTo investigate if the nicotine metabolite ratio (NMR, the ratio of nicotine metabolites 3'-hydroxycotinine/cotinine) is a reliable phenotypic biomarker for nicotine clearance across races, and as a function of differences in the rate of nicotine, cotinine and 3'-hydroxycotinine glucuronidation and UGT genotypes.MethodsParticipants [Caucasians (Whites), African Americans (Blacks) and Asian-Americans (Asians)] received an oral solution of deuterium-labeled nicotine and its metabolite cotinine. Plasma and saliva concentrations of nicotine and cotinine were used to determine oral clearances. Rates of glucuronidation were assessed from urine glucuronide/parent ratios, and UGT2B10 and UGT2B17 genotypes from DNA.ResultsAmong the 227 participants, 96 (42%) were White, 67 (30%) Asian and 64 (28%) Black. Compared to the other two races, Whites had higher nicotine and cotinine total oral clearance, Blacks had lower nicotine and cotinine glucuronidation rates and Asians had lower 3'-hydroxycotinine glucuronidation rates. A strong positive correlation (correlations coefficients 0.77-0.84; P l 0.001) between NMR and nicotine oral clearance was found for all three races, and NMR remained a strong predictor for the nicotine oral clearance while adjusting for race, sex and age. Neither the metabolite glucuronidation ratios nor the UGT genotypes had significant effects on the ability of NMR to predict nicotine oral clearance.ConclusionNMR appears to be a reliable phenotypic biomarker for nicotine clearance across races, glucuronidation phenotypes and genotypes. Racial differences in the relationships between NMR, smoking behaviors and addiction are unlikely to be related to an inadequate estimation of nicotine clearance on the basis of NMR.

The Nicotine Metabolite Ratio (NMR; 3-hydroxycotinine/cotinine), a highly heritable index of nicotine metabolic inactivation by the CYP2A6 enzyme, is associated with numerous smoking behaviors and diseases, as well as unique cessation outcomes. However, the NMR cannot be measured in nonsmokers, former smokers, or intermittent smokers, for example, in evaluating tobacco-related disease risk. Traditional pharmacogenetic groupings based on CYP2A6 * alleles capture a modest portion of NMR variation. We previously created a CYP2A6 weighted genetic risk score (wGRS) for European (EUR)-ancestry populations by incorporating independent signals from genome-wide association studies to capture a larger proportion of NMR variation. However, CYP2A6 genetic architecture is unique to ancestral populations. In this study, we developed and replicated an African-ancestry (AFR) wGRS, which captured 30-35% of the variation in NMR. We demonstrated model robustness against known environmental sources of NMR variation. Furthermore, despite the vast diversity within AFR populations, we showed that the AFR wGRS was consistent between different US geographical regions and unaltered by fine AFR population substructure. The AFR and EUR wGRSs can distinguish slow from normal metabolizers in their respective populations, and were able to reflect unique smoking cessation pharmacotherapy outcomes previously observed for the NMR. Additionally, we evaluated the utility of a cross-ancestry wGRS, and the capacity of EUR, AFR, and cross-ancestry wGRSs to predict the NMR within stratified or admixed AFR-EUR populations. Overall, our findings establish the clinical benefit of applying ancestry-specific wGRSs, demonstrating superiority of the AFR wGRS in AFRs.

Background Cigarette smoking is associated with an increased risk of developing ARDS. However, whether changes in smoking patterns or processes of care impact this relationship is unclear. Research Question Are changes in smoking and resuscitation patterns associated with changes in the relationship between smoking and ARDS? Study Design and Methods We conducted a prospective cohort study of critically injured adults with blunt trauma from 2005 to 2015. Plasma cotinine, a tobacco biomarker, was measured to categorize patients by smoking status. We used regression to assess the relationship between smoking, resuscitation practices, and ARDS over time. Results In the overall cohort, active (OR, 1.9; 95% CI, 1.0-3.5; P = .046) and passive (OR, 2.6; 95% CI, 1.4-4.8; P = .002) smoking were associated with an increased risk of developing ARDS in multivariate analyses. In contrast to the dose-response relationship in patients enrolled from 2005 to 2008, passive cigarette smoke exposure was associated with the highest risk of developing ARDS in patients enrolled from 2009 to 2015, suggesting a threshold effect. Packed RBC (pRBC) and fresh frozen plasma (FFP) transfusions were associated with an increased risk of developing ARDS, particularly in active smokers (pRBC: OR, 5.6; P Interpretation Despite changes in resuscitation and smoking patterns, cigarette smoking remains associated with an increased risk of developing ARDS. However, this relationship changed over time, with passive smokers at particularly increased risk of developing ARDS in later years, which may be related to changes in smoking patterns or transfusion practices over time. These findings highlight the need for additional mechanistic and epidemiologic studies of the effects of low levels of cigarette smoke exposure on lung health.

ObjectiveIn an urban adolescent population, we evaluated sources of exposure to secondhand smoke exposure (SHS), examined differences in exposure by race/ethnicity, age and sex, and determined the relationship between exposure source(s) and the biomarkers cotinine and NNAL.MethodsParticipants were recruited from a public hospital-based outpatient clinic in San Francisco, CA, USA.ResultsOf a sample of N=298 adolescents screened, 235 were biologically confirmed to be exposed to tobacco smoke. Of those, N=16 were active smokers and N=219 were exposed to SHS; 91 (39%) were heavily SHS exposed (median cotinine=0.76 ng/mL) and 128 (54%) had light SHS exposure (median cotinine=0.11 ng/mL). Within those SHS exposed, the most common source of exposure was in a public area. No significant racial/ethnic differences were found, although African American adolescents were more likely to live in a home that allowed smoking. Older adolescents were more likely to be exposed across several difference sources, and females more likely to be exposed in a car and in public areas. Past 7-day exposure in the home, in a car, and current blunt use were significantly related to biomarkers of exposure.ConclusionsUrban adolescents are exposed to SHS across a variety of sources. Although exposure in a public area is most common, exposure in the home and in cars significantly influences tobacco biomarker levels. Interventions to reduce exposure would have the greatest impact in this population if they focused on reducing exposure in the home and in cars. History of blunt use is a strong determinant of tobacco exposure.

Background Nicotine, the pharmacologically active substance in both tobacco and many electronic cigarette (e-cigarette) liquids, is responsible for the addiction that sustains cigarette smoking. With 8 million deaths worldwide annually, smoking remains one of the major causes of disability and premature death. However, nicotine also plays an important role in smoking cessation strategies. Objectives The aim of this study was to develop a comprehensive, whole-body, physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) model of nicotine and its major metabolite cotinine, covering various routes of nicotine administration, and to simulate nicotine brain tissue concentrations after the use of combustible cigarettes, e-cigarettes, nicotine gums, and nicotine patches. Methods A parent–metabolite, PBPK/PD model of nicotine for a non-smoking and a smoking population was developed using 91 plasma and brain tissue concentration–time profiles and 11 heart rate profiles. Among others, cytochrome P450 (CYP) 2A6 and 2B6 enzymes were implemented, including kinetics for CYP2A6 poor metabolizers. Results The model is able to precisely describe and predict both nicotine plasma and brain tissue concentrations, cotinine plasma concentrations, and heart rate profiles. 100% of the predicted area under the concentration–time curve (AUC) and maximum concentration (Cmax) values meet the twofold acceptance criterion with overall geometric mean fold errors of 1.12 and 1.15, respectively. The administration of combustible cigarettes, e-cigarettes, nicotine patches, and nicotine gums was successfully implemented in the model and used to identify differences in steady-state nicotine brain tissue concentration patterns. Conclusions Our PBPK/PD model may be helpful in further investigations of nicotine dependence and smoking cessation strategies. As the model represents the first nicotine PBPK/PD model predicting nicotine concentration and heart rate profiles after the use of e-cigarettes, it could also contribute to a better understanding of the recent increase in youth e-cigarette use. Electronic supplementary material The online version of this article (10.1007/s40262-020-00880-4) contains supplementary material, which is available to authorized users.

The most important tobacco-specific nitrosamine found in cigarette smoke and formed in ageing smoke after cigarettes are extinguished is 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). It is formed from nitrosation of nicotine, under particular conditions both in indoor and outdoor environments. NNK has been classified as a potent lung carcinogen which is expected to be found primarily in the particle-phase and to be stable in particulate matter. In this study tests have been carried out to show that a bisulfate-treated filter is more efficient than an untreated filter to collect both nicotine and NNK, and that the latter is stable in outdoor particulate matter. To characterize NNK in the outdoor environment, airborne samples were collected from 11 cities in USA, UK, Hong Kong and Malta with characteristics varying from low to high population densities and from urban to suburban to rural, and with desert characteristics and distinct climates. It has been shown that airborne particle + gas phase nicotine and particle-phase NNK behave in a linearly correlated manner. A seasonal analysis was carried out on a subset of data available from five sites in California, where the load of NNK in PM10 is driven by long range transport of the air masses passing over densely populated cities. In the winter season, the load of NNK in PM is higher than in summer in a statistically significant manner. The contamination of PM with NNK shows variability, but is observed at all sites. This paper highlights the potential risk of chronic exposure to NNK in particulate matter by the inhalation pathway.

Background As of March 2019, JUUL electronic cigarettes are the most popular e-cigarette on the U.S. market, but little is known of nicotine exposure and dependence on JUUL and user experience. Methods JUUL users participated in a community-based study involving questionnaires, saliva collection and a qualitative interview. Results Fifteen participants were enrolled (80% male, 53% White) and had an average age of 29.8 (standard deviation = 10) years. Daily exposure to nicotine assessed via salivary cotinine was similar to those reported for other e-cigarette and tobacco cigarette users in general. The majority reported low to moderate nicotine dependence. Qualitative interview themes included: the importance of social networks in adoption and use of the product; device features such as small size and vapor cloud reinforced product use; the product provided satisfaction compared to a tobacco cigarette; and a perceived sense of addiction to the product. Conclusions JUUL e-cigarettes expose users to levels of nicotine similar to other e-cigarettes but may be more satisfying due to unique device features. JUUL may be quite acceptable to tobacco cigarette smokers who are seeking to quit. However, it holds addictive potential and can reinforce long-term nicotine use.

Author(s): Weinstein, John R; Diaz-Artiga, Anaite; Benowitz, Neal; Thompson, Lisa M | Abstract: BackgroundHousehold air pollution from solid fuels is a leading risk factor for morbidity and mortality worldwide. Pregnant women's exposure to polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs), two components of solid-fuel smoke, is associated with adverse birth outcomes. Even with improved solid-fuel stoves, exposure to PAHs and VOCs remains high. Therefore, cleaner cooking fuels need to be prioritized.ObjectiveWe aimed to quantify exposure reduction to PAHs and VOCs among pregnant women in rural Guatemala with a liquefied petroleum gas (LPG) stove intervention.Materials and methodsUrine from pregnant women (N = 50) was collected twice: at l20 weeks gestation, when women cooked exclusively with wood, and 6-8 weeks after receiving an LPG stove. Metabolites of four PAHs and eight VOCs were analyzed. Concurrent with urine collection, personal 48-h PM2.5 exposure was measured.ResultsWomen cooking exclusively with wood were exposed to high levels of particulate matter (PM2.5), which was reduced by 57% with the LPG stove. Urinary concentrations of total PAH metabolites (-37%), PMA (benzene metabolite; -49%), and CNEMA (acrylonitrile metabolite; -51%) were reduced. However, recent use of a wood-fired sauna bath led to large increases in excretion of urinary toxicant metabolites (+66-135%).ConclusionsThis is the first study to report PAH and VOC reductions from an LPG stove intervention introduced during pregnancy. However, other sources of air pollution minimized the gains seen from using an LPG stove. Thus, all sources of air pollution must be addressed in concert to reduce exposures to levels that protect health.

Introduction Approximately the same percentage of male high school students in the United States currently uses conventional smokeless tobacco as smokes cigarettes, resulting in toxin exposure. Methods This study assessed tobacco product use (smokeless, combustible, and electronic cigarettes) and nicotine and carcinogen exposures in a sample of 594 male rural high school baseball players—a population traditionally at risk for smokeless tobacco use. Salivary specimens were assayed for cotinine (a biomarker of nicotine exposure) and urine specimens for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL, a biomarker of the carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) using liquid chromatography–tandem mass spectrometry. Results The prevalence of past 30-day use of any tobacco product was 29%. Past 7-day smokeless tobacco use (prevalence: 13%) was associated with the highest levels of cotinine and NNAL observed in the sample, whether smokeless tobacco was used exclusively (geometric means: cotinine 11.1 ng/mL; NNAL 31.9 pg/mg-creatinine) or in combination with combustible products (geometric means: cotinine 31.6 ng/mL; NNAL 50.0 pg/mg creatinine). Cotinine and NNAL levels were incrementally higher in each increasing category of smokeless tobacco use frequency. However, observed levels were lower than previously reported for adults, likely reflecting less smokeless use per day among adolescents. Conclusions Based on these biomarker observations, adolescents who use conventional smokeless tobacco products are exposed to substantial levels of nicotine and NNK. Although exposed to lower levels than adult smokeless users, the findings are concerning given the young age of the sample and tendency for smokeless tobacco users to increase use intensity over time. Implications This study demonstrates that adolescents using smokeless tobacco are exposed to levels of nicotine and NNK that increase with use frequency and that exceed exposures among peers using other tobacco products. Youth smokeless tobacco use in the United States has not declined along with youth smoking prevalence, giving greater importance to this health concern. To reduce youth (and adult) exposures, needed actions include effective smokeless tobacco use prevention, potentially in combination with reducing the levels of harmful and potentially harmful chemicals in smokeless tobacco products currently popular among adolescents.

Aims To review cytisine's history of use, pre-clinical evidence, clinical pharmacokinetics, efficacy, adverse reactions (ARs) and safety for smoking cessation. Methods A synoptic review of the use of cytisine as a smoking cessation medication, mechanism of action, pharmacokinetics and safety. Relevant literature on data included in these sections were identified through a search of 11 databases with additional literature obtained from reports and monographs. Three databases (PubMed, EMBASE and www.elibrary.ru) were systematically searched for studies published from 2012 to August 2018 in any language to provide an updated meta-analysis of cytisine's efficacy and ARs for smoking cessation compared with placebo. We pooled the relative risks (RR) of abstinence in the efficacy analysis and RR of ARs, either reported by the authors or calculated from the reports. Results Cytisine has been in use since 1964 and is currently marketed in 18 countries. Systemic bioavailability from oral ingestion is high and clearance is primarily renal, with minimal or no metabolism. Brain uptake in animal models is moderate. The plasma half-life averages 4.8 hours. Eight studies were included for meta-analysis of efficacy. With heterogeneous results, the overall RR versus placebo of successful continuous abstinence at the longest follow-up was 1.74 [95% confidence interval (CI) = 1.38-2.19]. Nausea, vomiting, dyspepsia, upper abdominal pain and dry mouth that were mild or moderate were the most common ARs, with RR versus placebo 1.10 (95% CI = 0.95-1.28). The cost of cytisine in eastern and central Europe is several-fold less than that of other smoking cessation medications. Conclusions Cytisine is a low-cost medication found to increase the likelihood of smoking cessation. The most frequently reported ARs of cytisine involve gastrointestinal symptoms that are mostly reported as either mild or moderate in severity.

Background Electronic cigarettes (e-cigarettes) have drastically changed the nicotine and tobacco product landscape. However, their potential public health impact is still unclear. A reliable and valid measure of e-cigarette dependence would likely advance assessment and prognostication of the public health impact of e-cigarettes. The aim of this research was to examine the internal consistency, structure, and validity of three e-cigarette dependence scales. Methods Adult dual users (smokers who also vape, N = 256) enrolled in an observational cohort study (45.1% women, 70.7% white). At baseline, participants completed the e-cigarette Fagerström Test of Cigarette Dependence (e-FTCD), the e-cigarette Wisconsin Inventory of Smoking Dependence Motives (e-WISDM), and the Penn State Electronic Cigarette Dependence Index (PS-ECDI). All participants provided a urine sample for cotinine analysis and reported e-cigarette use at 1 year. Results The e-WISDM subscales had the highest internal consistency (α = .81–.96), then the PS-ECDI (α = .74) and e-FTCD (α = .51). A single-factor structure for the e-FTCD and an 11-factor structure for the e-WISDM were supported, but the PS-ECDI did not have a single-factor structure. All three e-cigarette dependence scales were highly correlated with validation criteria including continued e-cigarette use at 1 year, but not with e-liquid nicotine concentration or cotinine. Conclusions The e-WISDM and PS-ECDI had stronger internal consistency than did the e-FTCD, despite the e-FTCD’s single-factor structure, but all 3 measures appear to be valid measures of e-cigarette dependence as suggested by their significant relations with self-perceived addiction, heavy use, early use after overnight deprivation, and continued use over time. Implications This research provides empirical support for three e-cigarette dependence measures: the e-FTCD, the PS-ECDI, and the e-WISDM among dual users of e-cigarettes and combustible cigarettes. The PS-ECDI and e-WISDM are more reliable, but all three measures were strongly correlated with key dependence constructs such as heavy use and continued use over time.

Introduction Accurate measurement of nicotine exposure from cigarette smoke is important in studying disease risk and level of dependence. Urine total nicotine equivalents, the molar sum of nicotine and six metabolites (NE7), accounts for more than 90% of a nicotine dose and is independent of individual metabolic differences. However, measuring NE7 is technically difficult and costly. We compared NE7, the gold standard of nicotine intake, with different combinations of fewer urinary nicotine metabolites. We also examined the impact of individual differences in nicotine metabolic rate, sex, and race on strength of association with NE7. Methods Urine samples from 796 daily smokers, who participated across five clinical studies, were assayed for nicotine and/or metabolites. Associations with NE7 were assessed by regression and Bland–Altman analyses. Results Overall, the molar sum of urine [cotinine + 3′-hydroxycotinine (3HC)] (NE2) and [nicotine + cotinine + 3HC] (NE3) were strongly correlated with NE7 (r = .97 and .99, respectively). However, in slow metabolizers NE2 was less predictive of NE7, whereas NE3 was equally robust. Urine total cotinine was also strongly correlated with NE7 (r = .87). Conclusions Urine NE3 is a robust biomarker of daily nicotine intake, independently of individual metabolic differences, whereas NE2 is less accurate in slow metabolizers. Our findings inform the selection of more rigorous and cost-effective measures to assess nicotine exposure in tobacco research studies. Implications The molar sum of urine total nicotine, cotinine and 3HC (NE3) is a robust biomarker of daily nicotine intake, independently of individual metabolic differences, and performs as well as measuring seven nicotine metabolites (NE7). The sum of cotinine and 3HC (NE2) is less accurate in slow metabolizers. Our findings inform the selection of more rigorous and cost-effective measures to assess nicotine exposure in tobacco research studies.

Background Black-white differences in smoking abstinence are not well understood. This trial sought to confirm previously reported differences in quitting between blacks and whites and to identify factors underlying this difference. Methods During enrollment, 224 black and 225 white low-income smokers were stratified on race and within race on age and sex to ensure balance on these factors known to impact abstinence. The intervention included varenicline for 12 weeks and six guideline-based smoking cessation counseling sessions. The primary endpoint was cotinine-verified 7-day point prevalence smoking abstinence at week 26. A priori socioeconomic, smoking, treatment process (eg, treatment utilization, side effects, withdrawal relief), psychosocial, and biological factors were assessed to investigate race differences in abstinence. Unadjusted odds ratios (OR) were used to compare abstinence between blacks and whites. Adjusted odds ratios from logistic regression models were used to examine predictors of abstinence. All statistical tests were two-sided. Results Blacks were less likely to achieve abstinence at week 26 (14.3% vs 24.4%, OR = 0.51, 95% confidence interval [CI] = 0.32 to 0.83, P = .007). Utilizing best subsets logistic regression, five factors associated with race jointly predicted abstinence: home ownership (yes/no, OR = 3.03, 95% CI = 1.72 to 5.35, P Conclusions The race difference in abstinence was fully explained by lack of home ownership, lower income, greater neighborhood problems, higher baseline cotinine, and higher visit completion, which were disproportionately represented among blacks. Findings illuminate factors that make it harder for blacks in the United States to quit smoking relative to whites and provide important areas for future studies to reduce tobacco-related health disparities.

Background Electronic hookah (e‐hookah) vaping has increased in popularity among youth, who endorse unsubstantiated claims that flavored aerosol is detoxified as it passes through water. However, e‐hookahs deliver nicotine by creating an aerosol of fine and ultrafine particles and other oxidants that may reduce the bioavailability of nitric oxide and impair endothelial function secondary to formation of oxygen‐derived free radicals. Methods and Results We examined the acute effects of e‐hookah vaping on endothelial function, and the extent to which increased oxidative stress contributes to the vaping‐induced vascular impairment. Twenty‐six healthy young adult habitual hookah smokers were invited to vape a 30‐minute e‐hookah session to evaluate the impact on endothelial function measured by brachial artery flow‐mediated dilation (FMD). To test for oxidative stress mediation, plasma total antioxidant capacity levels were measured and the effect of e‐hookah vaping on FMD was examined before and after intravenous infusion of the antioxidant ascorbic acid (n=11). Plasma nicotine and exhaled carbon monoxide levels were measured before and after the vaping session. Measurements were performed before and after sham‐vaping control experiments (n=10). E‐hookah vaping, which increased plasma nicotine (+4.93±0.92 ng/mL, P P =0.479), increased mean arterial pressure (11±1 mm Hg, P P P P =0.002). All parameters were unchanged during sham studies. Conclusions E‐hookah vaping has adverse effects on vascular function, likely mediated by oxidative stress, which overtime could accelerate development and progression of cardiovascular disease. Registration URL: https://ClinicalTrials.gov . Unique identifier: NCT03690427.

ObjectiveIt is unclear why Black smokers in the United States have elevated risk of some tobacco-related diseases compared to White smokers. One possible causal mechanism is differential intake of tobacco toxicants, but results across studies are inconsistent. Thus, we examined racial differences in biomarkers of toxic volatile organic compounds (VOCs) present in tobacco smoke.MethodWe analyzed baseline data collected from 182 Black and 184 White adult smokers who participated in a randomized clinical trial in 2013-2014 at 10 sites across the United States. We examined differences in urinary levels of ten VOC metabolites, total nicotine equivalents (TNE), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), controlling for covariates such as cigarettes per day (CPD), as well as differences in VOCs per TNE to assess the extent to which tobacco exposure, and not metabolic factors, accounted for racial differences.ResultsConcentration of metabolites of acrolein, acrylonitrile, ethylene oxide, and methylating agents were significantly higher in Blacks compared to Whites when controlled for covariates. Other than the metabolite of methylating agents, VOCs per TNE did not differ between Blacks and Whites. Concentrations of TNE/CPD and VOCs/CPD were significantly higher in Blacks. Menthol did not contribute to racial differences in VOC levels.ConclusionsFor a given level of CPD, Black smokers likely take in higher levels of acrolein, acrylonitrile, and ethylene oxide than White smokers. Our findings are consistent with Blacks taking in more nicotine and toxicants per cigarette smoked, which may explain their elevated disease risk relative to other racial groups.

Electronic nicotine delivery systems (ENDS) such as e-cigarettes and heated tobacco products are novel battery-operated devices that deliver nicotine without combustion of tobacco. Because cigarette smoking is sustained by nicotine addiction and the toxic combustion products are mainly responsible for the harmful effects of smoking, ENDS could be used to promote smoking cessation while exposing users to lower levels of toxicants compared with conventional cigarettes. The currently available evidence from clinical and observational studies indicates a potential role of e-cigarettes as smoking cessation aids, although many continue to use e-cigarettes long after quitting smoking. Nicotine and toxicant delivery vary considerably by device and depend on the characteristics of the e-liquid formulation. Because smokers tend to titrate their nicotine intake to maintain their desired pharmacologic effects, device and liquid characteristics need to be considered when using ENDS as an aid to quit smoking. Factors potentially limiting their use are the currently still unknown long-term safety of these products and concerns regarding widespread use among youth. Implications of clinical pharmacology data on ENDS for the cigarette endgame and regulation by the U.S. Food and Drug administration are discussed.

Nicotine is inactivated by the polymorphic CYP2A6 enzyme to cotinine and then to 3′hydroxycotinine. The Nicotine Metabolite Ratio (NMR; 3′hydroxycotinine/cotinine) is a heritable nicotine metabolism biomarker, varies with sex and ancestry, and influences smoking cessation and disease risk. We conducted sex-stratified genome-wide association studies of the NMR in European American (EA) and African American (AA) smokers (NCT01314001, NCT00666978). In EA females (n = 389) and males (n = 541), one significant (P CYP2A6 (intronic), for C vs. T: females: beta = 0.67, P = 7.5e−22, 21.8% variation explained; males: beta = 0.75, P = 1.2e−37, 26.1% variation explained). In AA females (n = 503) and males (n = 352), the top variant was found on chromosome 19 but differed by sex (females: rs11878604, CYP2A6 (~ 16 kb 3′), for C vs. T: beta = − 0.71, P = 6.6e−26, 16.2% variation explained; males: rs3865454, CYP2A6 (~ 7 kb 3′), for G vs. T: beta = 0.64, P = 1.9e−19, 18.9% variation explained). In AA females, a significant region was found on chromosome 12 (top variant: rs12425845: P = 5.0e−9, TMEM132C (~ 1 Mb 5′), 6.1% variation explained) which was not significant in AA males. In AA males, significant regions were found on chromosomes 6 (top variant: rs9379805: P = 4.8e−9, SLC17A2 (~ 8 kb 5′), 8.0% variation explained) and 16 (top variant: rs77368288: P = 3.5e−8, ZNF469 (~ 92 kb 5′), 7.1% variation explained) which were not significant in AA females. Further investigation of these associations outside of chromosome 19 is required, as they did not replicate. Understanding how sex and ancestry influence nicotine metabolism genetics may improve personalized approaches for smoking cessation and risk prediction for tobacco-related diseases.

Key Points Question What is the effect of using nicotine salt pod system (NSPS) electronic cigarettes (e-cigarettes) for replacing cigarettes (ie, switching) on biomarkers of tobacco exposure and potential harm among cigarette smokers? Findings In this randomized clinical trial including 186 African American and Latinx adult smokers, those randomized to the e-cigarette condition maintained their cotinine levels and significantly reduced urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and carbon monoxide levels and respiratory symptoms compared with controls smoking as usual at week 6. Lung function and blood pressure remained unchanged. Meaning This randomized clinical trial found that switching to NSPS e-cigarettes among adult smokers did not increase nicotine exposure and led to short-term reduction in the major pulmonary carcinogen, NNAL, compared with continued smoking., This randomized clinical trial examines biomarkers of carcinogen exposure in African American and Latinx smokers who switch to electronic cigarettes vs smoking as usual., Importance Fourth-generation nicotine salt pod system (NSPS) electronic cigarettes (e-cigarettes) are the leading class of e-cigarettes. They contain high nicotine concentrations, which may facilitate switching among smokers, but could also lead to increased exposure to nicotine and biomarkers of potential harm. African American and Latinx smokers experience significant tobacco-related health disparities. The potential of NSPS e-cigarettes to reduce smoking-related harm among these groups is unknown. Objective To compare the harm reduction potential of NSPS e-cigarette vs combustible cigarettes. Design, Setting, and Participants This unblinded randomized clinical trial compared 6 weeks of e-cigarette use vs cigarettes as usual from to 2018 to 2019 among smokers in the San Diego, California, and Kansas City, Missouri, areas. Participants included African American and Latinx adult combustible cigarette smokers who smoked at least 5 cigarettes/d on at least 25 of the past 30 days for at least 6 months and were interested in switching to e-cigarettes. Data were analyzed from September 18, 2019, to September 4, 2020. Interventions 6 weeks of e-cigarette use in a choice of pod flavors (5% nicotine) along with brief education, training, and action planning to completely switch to e-cigarettes from combustible cigarettes. The control group smoked combustible cigarettes as usual. Main Outcomes and Measures The primary outcome was reduction in urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) concentration at week 6. Secondary outcomes were change in urinary cotinine, expired carbon monoxide (CO), respiratory symptoms, lung function, blood pressure, past 7-day consumption of combustible cigarettes, and switching rates (e-cigarette group only) at weeks 2 and 6. Results This study included 186 participants, including 92 African American participants and 94 Latinx participants. The mean (SD) age was 43.3 (12.5) years, and 75 (40.3%) were women. Participants smoked a mean (SD) of 12.1 (7.2) cigarettes/d on 6.8 (0.6) d/wk at baseline. A total of 125 participants were randomized to the e-cigarette group and 61 were randomized to the control group. At baseline, median (interquartile range) NNAL was 124 (45-197) pg/mL in the e-cigarette group and 88 (58-197) pg/mL in the control group. At week 6, the e-cigarette group had significantly greater reductions in NNAL (relative risk [RR], 0.36 [95% CI, 0.23-0.54]; P

BACKGROUND: Variation in CYP2A6 activity influences tobacco smoking behaviors and smoking-related health outcomes. Plasma Nicotine Metabolite Ratio (NMR) is a robust phenotypic biomarker of CYP2A6 activity and nicotine clearance. In urine, the NMR has been calculated as a ratio of free trans-3’-hydroxycotinine to free cotinine (NMR(F/F)), total trans-3’-hydroxycotinine to free cotinine (NMR(T/F)), or total trans-3’-hydroxycotinine to total cotinine (NMR(T/T)). We evaluated these three urinary NMR versions relative to plasma NMR and nicotine clearance and elucidated mechanisms of discrepancies among them. METHODS: Baseline plasma and urine biomarker data were available from two smoking cessation clinical trials and one nicotine pharmacokinetic study (total N=768). NMRs were compared using Pearson correlations, linear regressions and ANOVA analyses. UGT2B10 and UGT2B17 were genotyped. RESULTS: Urinary NMR(T/F) was the most highly related to plasma NMR (R(2)=0.70, P urinary NMR(T/F) > NMR(F/F) > NMR(T/T) (R(2)=0.41>0.37>0.35>0.25 respectively). CONCLUSION: Urinary NMR(T/F) followed by NMR(F/F) are the best urinary alternatives to plasma NMR or nicotine clearance. NMR(T/T) has the least utility as it is influenced substantially by variation in cotinine glucuronidation. IMPACT: This work highlighted the variation in urinary NMRs, and identified mechanisms for disparities among them, which facilitates their use in predicting smoking-related outcomes.

OBJECTIVE: Evaluate efficacy and safety of varenicline, bupropion, and nicotine replacement therapy (NRT) for smoking cessation in smokers with schizophrenia spectrum disorders in post-hoc analyses of EAGLES data. METHODS: Smokers with a schizophrenia spectrum disorder (n=390) and without a psychiatric illness (controls) (n=4,028) were randomly assigned to varenicline, bupropion, NRT, or placebo for 12 weeks. Outcomes included abstinence rates during treatment and follow-up, number needed to treat (NNT) for abstinence, incidence of neuropsychiatric adverse events, and temporal relationship between neuropsychiatric adverse events and abstinence status. RESULTS: Smokers with schizophrenia smoked more, had greater dependence, and fewer prior trials of cessation pharmacotherapy. At each timepoint, on varenicline, smokers with schizophrenia had significantly greater odds of abstinence than placebo and comparable NNT with controls. Bupropion and NRT increased odds of abstinence, though confidence intervals included one for some comparisons and produced greater NNT in smokers with schizophrenia than controls. No treatment was associated with significantly more neuropsychiatric adverse events than placebo in either cohort. The estimated neuropsychiatric adverse event rate was 5% (95% CI=3.0–7.7) in smokers with schizophrenia and 1% (95% CI=.6–2.1) in controls. Over one-third of neuropsychiatric adverse events occurred during partial or full abstinence, suggesting a multifactorial nature of neuropsychiatric adverse events. CONCLUSIONS: In smokers with schizophrenia, varenicline was associated with significantly higher abstinence rates than NRT, bupropion, and placebo, and had NNT comparable with smokers without psychiatric disorders. A significant proportion of neuropsychiatric adverse events occurred during early abstinence. No treatment significantly increased neuropsychiatric adverse event prevalence.

Introduction We illustrate the differential impact of common analysis approaches to handling urinary creatinine, a measure for urine dilution, on relationships between race, gender, and biomarkers of exposure measured in spot urine. Methods In smokers, spot urine levels of total nicotine equivalents (TNE, sum of total nicotine, total cotinine, and total 3′-hydroxycotinine) and total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) overall and per cigarette were examined. Relationships between race (African Americans [AA] n = 373, Whites n = 758) or gender (males n = 629, females n = 502) and TNE or NNAL were examined using the following approaches to handling creatinine: (1) unadjusted/unstandardized; (2) standardization; (3) adjustment as a covariate. Significance was considered at p < .05 Results Creatinine was higher in AA versus Whites (1.19 vs. 0.96 mg/mL; p < .0001) and in males versus females (1.21 vs. 0.84 mg/mL; p < .0001). Independent of how creatinine was handled, TNE was lower among AA than Whites (TNE ratios AA vs. Whites: 0.67–0.84; p’s < .05). Unadjusted TNE per cigarette was higher among AA versus Whites (ratio 1.12; p = .0411); however, the relationship flipped with standardization (ratio 0.90; p = .0360) and adjustment (ratio 0.95; p = .3165). Regarding gender, unadjusted TNE was higher among males versus females (ratio 1.13; p = .0063), but the relationship flipped with standardization (ratio 0.79; p < .0001) or adjustment (ratio 0.89; p = .0018). Unadjusted TNE per cigarette did not differ across gender (ratio 0.98; p = .6591), but lower levels were found in males versus females with standardization (ratio 0.68; p < .0001) and adjustment (ratio 0.74; p < .0001). NNAL displayed similar patterns. Conclusions Relationships between race, gender, and spot urine levels of biomarkers of exposure can vary greatly based on how creatinine is handled in analyses. Implications Lack of appropriate methods can lead to discrepancies across reports on variability of urinary biomarkers by race and gender. We recommend that for any analyses of biomarkers of exposure measure in spot urine samples across race, gender, or other population subgroups that differ in urinary creatinine levels, sensitivity analyses comparing the different methods for handling urinary creatinine should be conducted. If methods result in discrepant findings, this should be clearly noted and discussed.

Author(s): Harvanko, Arit M; St Helen, Gideon; Nardone, Natalie; Addo, Newton; Benowitz, Neal L | Abstract: Background and aimsRelative pharmacological effects of e-cigarettes and cigarettes during 24nhours of ad-libitum use have not been described. In this study, 24-hour blood plasma nicotine concentrations and 48-hour subjective effects with use of cigarettes and e-cigarettes were measured among dual users.DesignTwo-arm within-subject cross-over design with preferred e-cigarette or cigarette ad-libitum use over 48nhours.SettingHospital research ward in San Francisco, California, USA.ParticipantsThirty-six healthy dual users of e-cigarettes and cigarettes (nn=n8, 25% females).MeasurementsTwenty-four-hour blood plasma nicotine and cotinine concentrations and 48-hour self-reported nicotine withdrawal symptoms and rewarding effects.FindingsAnalyses used analysis of variance (ANOVA)-based mixed models with order of product (e-cigarette or cigarette) and product type (combustible cigarette or type of e-cigarette) as fixed effects, and subject as a repeated effect. During a 24-hour period, e-cigarettes produced lower nicotine exposure than cigarettes for the majority of users, although 25% received more nicotine from e-cigarettes, which was predicted by more frequent e-cigarette use or greater dependence. Compared to cigarette smoking, nicotine exposure for variable-power tank users was similar, while cig-a-like (t(30) n=n2.71, Pn=n0.011, dn=n0.745) and fixed-power tank users (t(30) n=n3.37, Pn=n0.002, dn=n0.993) were exposed to less nicotine. Cigarettes were rated higher than e-cigarettes on some desirable subjective effects (e.g. psychological reward, t(322) n=n7.24 Pnln0.001, dn=n0.432), but withdrawal symptom reduction was comparable. No differences were found between e-cigarette types, but Bayes factors indicate that these measures were insensitive.ConclusionsDuring a 24-hour period in a hospital setting in the United States, nicotine exposure for dual users of e-cigarettes and cigarettes was similar when using cigarettes or variable-power tank devices only but was lower for those using cig-a-like or fixed-power devices only. Despite lower nicotine levels, all types of e-cigarette were effective in preventing withdrawal symptoms. E-cigarettes were rated less rewarding than cigarettes.

School children may be exposed to secondhand smoke (SHS) either at home, in transit or in social gatherings permitting smoking in their presence. Questionnaires about SHS often underestimate prevalence and extent of exposure. A more accurate tool is the use of biomarkers such as cotinine (COT) and trans-3'-hydrocycotinine (3HC) as biomarkers of SHS exposure, alongside 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), a reduction product in the body of the tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), both potent carcinogens. We measured urinary COT, 3HC and total NNAL using sensitive and specific high-performance LC-MS/MS methods. The limit of quantification (LOQ) for each assay were 0.05ng/mL, 0.1ng/mL and 0.25pg/mL respectively. The aim of this study was to evaluate the exposure to SHS of school children (9-11 years), from five public schools in the island of Malta, from questionnaire information about smoking at home and verify it by urinary biomarker data of COT, 3HC and NNAL. These biomarkers were measurable in 99.4%, 95.4% and 98.3% of the participating children respectively. From the children reporting smoking at home, 11% had a history of asthma and had COT, 3HC and NNAL geometric mean concentrations double compared to the non-asthmatic group. In has been confirmed that non-smokers exposed to SHS and THS have a higher NNAL/COT ratio than the group identified as smokers according to specific and defined COT threshold levels (despite the fact that a priori, the entire study group was composed of non-smokers). The implication of high measured levels of urinary NNAL in children should be of concern given its potency. A main effects multifactor ANOVA model was developed and the children's house and school locations and the smoking frequency were statistically significant to predict the levels of the three metabolites. For 3HC only, the status of the employment of the mother was also an important predictor.

Tobacco use is the leading preventable cause of death worldwide and is a major risk factor for cardiovascular disease (CVD). Both prevention of smoking initiation among youth and smoking cessation among established smokers are key for reducing smoking prevalence and the associated negative health consequences. Proven tobacco cessation treatment includes pharmacotherapy and behavioral support, which are most effective when provided together. First-line medications (varenicline, bupropion, and nicotine replacement) are effective and safe for patients with CVD. Clinicians who care for patients with CVD should give as high a priority to treating tobacco use as to managing other CVD risk factors. Broader tobacco control efforts to raise tobacco taxes, adopt smoke-free laws, conduct mass media campaigns, and restrict tobacco marketing enhance clinicians' actions working with individual smokers.

Introduction The availability of electronic cigarettes (e-cigarettes) has profoundly changed the tobacco product landscape. In the United States, almost 6 million adults use both combustible and e-cigarettes (ie, dual users). The goal of this study was to understand how smokers and dual users differ in terms of demographics, cigarette dependence, and exposure to carcinogens. Methods An observational cohort (smokers, n = 166, ≥5 cigarettes/day for 6 months and no e-cigarette use in 3 months; dual users, n = 256, smoked daily for 3 months and used e-cigarettes at least once/week for the past 3 months) completed baseline assessments of demographics, tobacco use, and dependence. They also provided breath samples for carbon monoxide (CO) assay and urine samples for cotinine, 3-hydroxycotinine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) assays. Results Compared to smokers, dual users (mean e-cigarette use = 5.5 days/week [SD = 1.9]) were significantly younger and more likely to be white, have more education, report a history of psychiatric co-morbidity, and smoke fewer cigarettes per day. There were no differences in CO, cotinine, or 3-hydroxycotinine levels; however, dual users had significantly lower levels of NNAL than did smokers. Most smokers and dual users had no plans to quit smoking within the next year; 91% of dual users planned to continue using e-cigarettes for at least the next year. Conclusions In this community sample, dual users are supplementing their smoking with e-cigarette use. Dual users, versus smokers, smoked fewer cigarettes per day and delayed their first cigarette of the day, but did not differ in quitting intentions. Implications This comparison of a community sample of established dual users and exclusive smokers addresses key questions of dependence and health risks of dual use in real-world settings. Dual users were more likely to be white, younger, have more than a high school education and have a psychiatric history. Dual users also smoked significantly fewer cigarettes and had lower levels of NNAL (a carcinogen), but they did not differ from exclusive smokers in CO or cotinine levels, suggesting that they supplemented their nicotine intake via e-cigarettes.

This study investigated the influence of the rate of nicotine metabolism, as indicated by the nicotine metabolite ratio (NMR), on tobacco dependence. We stratified 136 smokers on the basis of saliva NMR as fast (n = 65) and slow (n = 71) metabolizers. Two “loading cigarettes” were smoked after overnight, and a “reward cigarette” was smoked after 6 hours of daytime, abstinence. Blood nicotine concentrations, expired carbon monoxide, withdrawal/craving, and reward questionnaires were collected before/after smoking and during daytime abstinence. Compared with slow metabolizers, fast metabolizers had a shorter nicotine elimination half-life (P < 0.001), lower plasma nicotine concentrations (P < 0.001), and higher withdrawal/craving scores (P < 0.05) for most times during daytime abstinence, indicating that fast metabolizers are likely smoking more to relieve withdrawal symptoms (negative reinforcement). Reward/satisfaction scores were similar in fast and slow metabolizers, suggesting that faster nicotine metabolism, assessed by NMR, is not associated with greater positive reinforcement. CYP2A6 normal (n = 82) and reduced (n = 42) genotype predicted plasma nicotine concentrations but not withdrawal symptoms.

Background: Biomarkers of tobacco exposure have a central role in studies of tobacco use and nicotine intake. The most significant exposure markers are nicotine itself and its metabolites in urine. Therefore, it is important to evaluate the performance of laboratories conducting these biomarker measurements. Methods: This report presents the results from a method performance study involving 11 laboratories from 6 countries that are currently active in this area. Each laboratory assayed blind replicates of seven human urine pools at various concentrations on three separate days. The samples included five pools blended from smoker and nonsmoker urine sources, and two additional blank urine samples fortified with pure nicotine, cotinine, and hydroxycotinine standards. All laboratories used their own methods, and all were based on some form of liquid chromatography/tandem mass spectrometry. Results: Overall, good agreement was found among the laboratories in this study. Intralaboratory precision was good, and in the fortified pools, the mean bias observed was < + 3.5% for nicotine, approximately 1.2% for hydroxycotinine, and less than 1% for cotinine (1 outlier excluded in each case). Both indirect and direct methods for analyzing the glucuronides gave comparable results. Conclusions: This evaluation indicates that the experienced laboratories participating in this study can produce reliable and comparable human urinary nicotine metabolic profiles in samples from people with significant recent exposure to nicotine. Impact: This work supports the reliability and agreement of an international group of established laboratories measuring nicotine and its metabolites in urine in support of nicotine exposure studies. Cancer Epidemiol Biomarkers Prev; 27(9); 1083–90. ©2018 AACR.

Background A non-invasive phenotypic indicator of the rate of nicotine metabolism is nicotine metabolite ratio (NMR) defined as a ratio of two major metabolites of nicotine – trans-3′-hydroxycotinine/cotinine. The rate of nicotine metabolism has important clinical implications for the likelihood of successful quitting with nicotine replacement therapy (NRT). We conducted a study to measure NMR among Polish smokers. Methods In a cross-sectional study of 180 daily cigarette smokers (42% men; average age 34.6 ± 13.0), we collected spot urine samples and measured trans-3′-hydroxycotinine (3-HC) and cotinine levels with LC–MS/MS method. We calculated NMR (molar ratio) and analyzed variations in NMR among groups of smokers. Results In the whole study group, an average NMR was 4.8 (IQR 3.4–7.3). The group of women below 51 years had significantly greater NMR compared to the rest of the population (6.4; IQR 4.1–8.8 vs. 4.3; IQR 2.8–6.4). No differences were found among group ages of male smokers. Conclusions This is a first study to describe variations in nicotine metabolism among Polish smokers. Our findings indicate that young women metabolize nicotine faster than the rest of population. This finding is consistent with the known effects of estrogen to induce CYP2A6 activity. Young women may require higher doses of NRT or non-nicotine medications for most effective smoking cessation treatment.

INTRODUCTION:While adherence to medication in smoking cessation clinical trials is strongly associated with clinical outcome, very few studies have evaluated the validity of pill count as a measure of adherence relative to a biological assay, and evaluated a broad range of correlates of adherence. METHODS:In a smoking cessation clinical trial of varenicline, we compared pill counts collected over 4 different time periods to varenicline salivary levels taken after 2weeks of treatment, as well as evaluated predictors of adherence to varenicline. RESULTS:Using a binary measure of adherence based on salivary varenicline levels, adherence was higher among older, white, and more educated participants. Relative to 3, 7, and 14-day pill count, 12-week pill count was the only significant measure able to discriminate adherence as defined by salivary varenicline levels (assessed by area under the receiver operating characteristic curve; AUC=0.59, p=0.004). Seventy-two percent of participants who indicated adherence on 12-week pill count were classified as adherent based on varenicline saliva levels (sensitivity=0.80; specificity=0.40). There was modest variability in the relationship between 12-week pill count and varenicline levels across race and rate of nicotine metabolism. Lastly, General Estimating Equation models demonstrated that longitudinal changes in withdrawal, craving, negative and positive affect, and side effect count and severity were not related to adherence based on salivary varenicline levels. CONCLUSIONS:These results indicate that 12-week pill count was the best, albeit a relatively weak, measure of varenicline adherence; additional factors associated with treatment adherence need to be identified.

BACKGROUND AND AIMS: The activity of CYP2A6, the major nicotine-inactivating enzyme, is measurable in smokers using the nicotine metabolite ratio (NMR; 3'hydroxycotinine/cotinine). Due to its role in nicotine clearance, the NMR is associated with smoking behaviours and response to pharmacotherapies. The NMR is highly heritable (~80%), and on average lower in African Americans (AA) versus whites. We previously identified several reduce and loss-of-function CYP2A6 variants common in individuals of African descent. Our current aim was to identify novel genetic influences on the NMR in AA smokers using genome-wide approaches. DESIGN: Genome-wide association study (GWAS). SETTING: Multiple sites within Canada and the United States. PARTICIPANTS: AA smokers from two clinical trials: Pharmacogenetics of Nicotine Addiction Treatment (PNAT)-2 (NCT01314001; n = 504) and Kick-it-at-Swope (KIS)-3 (NCT00666978; n = 450). MEASUREMENTS: Genome-wide SNP genotyping, the NMR (phenotype) and population substructure and NMR covariates. FINDINGS: Meta-analysis revealed three independent chromosome 19 signals (rs12459249, rs111645190 and rs185430475) associated with the NMR. The top overall hit, rs12459249 (P = 1.47e-39; beta = 0.59 per C (versus T) allele, SE = 0.045), located ~9.5 kb 3' of CYP2A6, remained genome-wide significant after controlling for the common (~10% in AA) non-functional CYP2A6*17 allele. In contrast, rs111645190 and rs185430475 were not genome-wide significant when controlling for CYP2A6*17. In total, 96 signals associated with the NMR were identified; many were not found in prior NMR GWASs in individuals of European descent. The top hits were also associated with the NMR in a third cohort of AA (KIS2; n = 480). None of the hits were in UGT or OCT2 genes. CONCLUSIONS: Three independent chromosome 19 signals account for ~20% of the variability in the nicotine metabolite ratio in African American smokers. The hits identified may contribute to inter-ethnic variability in nicotine metabolism, smoking behaviours and tobacco-related disease risk.

Non-cigarette other tobacco products (OTP; e.g., cigarillos, little cigars) are typically used in combination with cigarettes, but limited data exists on the tobacco toxicant exposure profiles of dual cigarette-OTP (Cig-OTP) users. This study examined biomarkers of nicotine and carcinogen exposure in cigarette smokers who used or did not use OTP.111 Cig-OTP and 111 cigarette only (Cig Only) users who smoked equivalent cigarettes per day were matched on age (40,=40), race (African American, White), and gender. Participants reported past 7-day daily use of cigarettes and OTP and provided urine for nicotine, cotinine, total nicotine equivalents (TNE) and total NNAL concentrations.Cig-OTP users reported greater past 7-day tobacco use (15.9 versus 13.0 products/day, p0.01) but had significantly lower creatinine-normalized nicotine (606 versus 1301ng/mg), cotinine (1063 versus 2125ng/mg), TNE (28 versus 57 nmol/mg) and NNAL (251 versus 343pg/mg) than Cig Only users (p0.001).Cig-OTP users had lower levels of nicotine and metabolites of a lung carcinogen relative to Cig-Only users, but concentrations of toxicants among Cig-OTP users were still at levels that place smokers at great risk from the detrimental health effects of smoking.Our study finds that nicotine and carcinogen exposure in Cig-OTP users are lower compared to cigarette only users, but still likely to be associated with substantial harm. A better understanding of why toxicant levels may be lower in Cig-OTP is an important area for future study.

Author(s): Taghavi, Taraneh; St Helen, Gideon; Benowitz, Neal L; Tyndale, Rachel F | Abstract: ObjectivesNicotine metabolism rates differ considerably among individuals, even after controlling for variation in the major nicotine-metabolizing enzyme, CYP2A6. In this study, the impact of genetic variation in alternative metabolic enzymes and transporters on nicotine and cotinine (COT) pharmacokinetics and smoking was investigated.MethodsWe examined the impact of UGT2B10, UGT2B17, FMO3, NAT1, and OCT2 variation on pharmacokinetics and smoking (total nicotine equivalents and topography) before and after stratifying by CYP2A6 genotype in 60 African American (AA) smokers who received a simultaneous intravenous infusion of deuterium-labeled nicotine and COT.ResultsVariants in UGT2B10 and UGT2B17 were associated with urinary glucuronidation ratios (glucuronide/free substrate). UGT2B10 rs116294140 was associated with significant alterations in COT and modest alterations in nicotine pharmacokinetics. These alterations, however, were not sufficient to change nicotine intake or topography. Neither UGT2B10 rs61750900, UGT2B17*2, FMO3 rs2266782, nor NAT1 rs13253389 altered nicotine or COT pharmacokinetics among all individuals (n=60) or among individuals with reduced CYP2A6 activity (n=23). The organic cation transporter OCT2 rs316019 significantly increased nicotine and COT Cmax (P=0.005, 0.02, respectively) and decreased nicotine clearance (P=0.05). UGT2B10 rs116294140 had no significant impact on the plasma or urinary trans-3'-hydroxycotinine/COT ratio, commonly used as a biomarker of CYP2A6 activity.ConclusionWe found that polymorphisms in genes other than CYP2A6 represent minor sources of variation in nicotine pharmacokinetics, insufficient to alter smoking in AAs. The change in COT pharmacokinetics with UGT2B10 rs116294140 highlights the UGT2B10 gene as a source of variability in COT as a biomarker of tobacco exposure among AA smokers.

BACKGROUND: Adherence to nicotine patches relates to cessation. This is the first study to examine the validity of self-reported nicotine patch adherence relative to saliva cotinine. METHODS: We used data from 198 clinical trial participants who received 11 weeks of nicotine patches, self-reported patch use, had saliva cotinine 1-week after the start of treatment assessed, and were not smoking when saliva was collected (CO≤6). Self-reported patch adherence was defined as: 3-day (before saliva collection), 7-day (before saliva collection), 3-week use (7 days before, and 14 days after, saliva collection), and 11-week use (7 days before, and 10 weeks after, saliva collection). Analyses, including receiver operating characteristic curves, considered differences in nicotine metabolism. Sensitivity, specificity and positive (PPV) and negative predictive value (NPV) assessed optimal cotinine cut-point for adherence. RESULTS: Self-reported 7-day (r=0.13) and 3-week (r=0.13) patch use marginally correlated with week 1 cotinine (p’s=0.08) but not 3-day or 11-week. Significant area under the curve (AUC) values of 0.67 (95%CI: 0.55–0.79) and 0.72 (95%CI: 0.57–0.88) were found using 7-day self-report for the overall sample and for slow metabolizers (p’s

Introduction Many electronic cigarette manufacturers have begun offering liquids containing “nicotine salts,” which are formed when an acid is mixed in a solution with free-base nicotine. Type of salt could play a significant role in the abuse liability of electronic cigarette liquids. As a first step to understanding nicotine salts, this study sought to identify the types of acids present in 23 commercially available electronic cigarette liquids. Aims and Methods Twenty-three electronic cigarette liquids advertised as containing nicotine salts were purchased for analysis. These liquids were tested for the presence of 11 different organic acids that were deemed likely to be used in a nicotine salt formulation. Liquids were analyzed using a combination of liquid chromatography–mass spectrometry and gas chromatography–mass spectrometry methods, then compared to authentic acid standards for identification. Results Six of the 11 possible acids were identified in the liquids, from most to least common: lactic, benzoic, levulinic, salicyclic, malic, and tartaric acid. Acid(s) could not be identified in one of the liquids. Though most liquids contained only one type, three of the liquids contained multiple acids. Conclusions These data demonstrate that several types of salts/acids are currently being used in electronic cigarette liquids. The type and concentration of salt(s) used in these liquids may differentially alter sensations in the throat and upper airway, and overall pharmacology of the aerosols by altering liquid pH and from flavor and sensory characteristics of the acids themselves. Implications This study demonstrates that at least six different types of acids are being used to create the nicotine salts in electronic cigarette liquids, with the acids lactic, benzoic, and levulinic being the most frequently identified. Identification of these acids can serve as the foundation for future research to determine if type of nicotine salt alters pharmacological and toxicological effects of electronic cigarettes.

RationaleThere is limited understanding regarding how various e-cigarette flavorings may influence the behavior of non-regular e-cigarette users who are regular cigarette smokers.ObjectivesTo assess differences in nicotine delivery, puffing topography, subjective effects, and user satisfaction from different flavored e-liquids.MethodsEighteen daily smokers (average age, 44.1 ± 7.0; 9 males; average CPD, 13.0 ± 5.8) smoked their tobacco cigarettes during an initial visit and returned five times to try an e-cigarette (eGo type) refilled with a nicotine solution (24 mg/ml) of five different flavors: cherry, tobacco, espresso, menthol, and vanilla (randomized order). Assessments at each visit included puffing topography, blood samples for nicotine analysis, and subjective reports of nicotine effects and flavor satisfaction.ResultsVaping different flavors resulted in different levels of plasma nicotine. The flavor producing the highest plasma nicotine concentration (Cmax) was cherry (median 21.2 ng/ml), which was not significantly different than nicotine delivery from a combustible cigarette (29.2 ng/ml, p > .05). Vanilla e-liquid produced the lowest Cmax (9.7 ng/ml), and participants tended to puff less frequently on vanilla compared to tobacco flavor (p = .013). Flavors did not differ significantly in the speed of nicotine delivery (Tmax). During controlled use, puff duration for all flavors was significantly longer than a combustible cigarette (p < 0.05). After controlling for nicotine delivery, significant differences in flavor enjoyment were detected. Menthol flavored e-liquid was rated as more enjoyable than vanilla and tobacco flavored e-liquids (p < 0.05).ConclusionsFlavors tested in this study yielded different patterns of nicotine delivery and led to differences in reduction in smoking urges.Trial registrationClinicalTrials.gov Identifier: #NCT02575885.

Author(s): Peng, Annie R; Swardfager, Walter; Benowitz, Neal L; Ahluwalia, Jasjit S; Lerman, Caryn; Nollen, Nicole L; Tyndale, Rachel F | Abstract: Background and aimsVarenicline effectiveness may be related to the level of adherence, which might be reduced by adverse effects such as nausea. The aim of the study was to test a possible effect of nausea on smoking cessation outcomes mediated by adherence.DesignMediation path analysis.SettingMultiple sites within Canada and the United States.ParticipantsTreatment-seeking smokers receiving varenicline from two smoking cessation clinical trials: Quit2Live (NCT01836276; n = 449) and Pharmacogenetics of Nicotine Addiction Treatment (PNAT) (NCT01314001; n = 421).MeasurementsNausea severity was collected through self-report and adherence was biologically assessed using varenicline concentrations (Quit2Live, plasma sample at week 4; PNAT, saliva sample at week 2). In Quit2Live, the end-points were cotinine-verified abstinence at weeks 4, 12 and 26. In PNAT, the end-points were carbon monoxide-verified abstinence at weeks 2, 12 and 26.FindingsEarly nausea was not directly associated with abstinence [odds ratio (OR) ranging from 0.73-1.28; P ≥ 0.26]. However early nausea was indirectly associated with lower cessation rates at multiple timepoints (ORs ranging from 0.92-0.94; 95% CI between 0.83-0.99) in a relationship mediated by reduced varenicline adherence (assessed by plasma varenicline concentrations) in the primary trial (Quit2Live). This relationship between nausea, adherence and cessation was similar in direction but weaker in effect size (ORs ranging from 0.98-0.99; 95% CI between 0.90-1.03) in a secondary trial (PNAT), where adherence was assessed using salivary varenicline concentrations.ConclusionsThese data suggest that early nausea during varenicline treatment may be indirectly associated with lower likelihood of smoking cessation through reducing varenicline adherence. Differences in robustness between the trials may be due to the different biological matrices (plasma vs. saliva) and/or timing used to assess varenicline adherence. The results of the first study suggest that improved management of early nausea during varenicline treatment may positively impact smoking cessation success through increasing varenicline adherence.

Background Assessing the prevalence and level of exposure (dose) of tobacco and marijuana use is important in studies of harm from use of these substances. We used biochemical analysis of urine to quantitatively assess exposure to nicotine and delta 9-tetrahydrocannabinol (THC) in adolescents receiving medical care in a public hospital Methods Participants were 686 adolescents between 12 and 21 years old seen at Zuckerberg San Francisco General Hospital between 2012 and 2014. Urine samples were assayed using high sensitivity liquid chromatographic assays for cotinine, a major metabolite of nicotine, and 11-nor-9-carboxy-delta 9-THC (THC−COOH), a major metabolite of THC. A commonly used immunoassay screen for THC−COOH was also performed. Results The THC−COOH immunoassay substantially underestimated THC exposure, as measured with the high sensitivity assay. THC use was detected in 25% of participants, with higher prevalence with increasing age and in non-Hispanic blacks. Active tobacco smokers had an 80% prevalence of THC use (odds ratio for cigarette smoking predicting THC use 13.2). Urine cotinine and THC−COOH were significantly correlated (r = 0.60). Conclusions The use of a high sensitivity chromatographic urine assay provides a much more complete picture of adolescent tobacco use compared to a commonly used immunoassay. The immunoassay provides high specificity but moderate sensitivity. We confirm high concordance of tobacco and marijuana use and the high predictive value of cigarette smoking in predicting marijuana use, and provide novel data on the quantitative correlation between level of exposure to nicotine and THC. Quantitative screening of nicotine and THC exposure may enhance our understanding of addiction and harm from single and dual product use.

Comparisons of systemic exposure to toxicants during monitored cigarette smoking, electronic cigarette (e-cigarette) use, and abstention are needed to enhance our understanding of the risks of e-cigarette use (vaping). In a cross-over study, we measured 10 mercapturic acid metabolites of volatile organic compounds (VOCs) in 24-hour urine samples collected from 36 dual users (8 women) of e-cigarettes and cigarettes during 2 days of ad libitum vaping or cigarette-only use, and 2 days of enforced abstention. Concentrations of VOC metabolites were higher during smoking compared with vaping, except for the methylating agents' metabolite. The fold-difference in concentrations when smoking relative to vaping ranged from 1.31 (1.06–1.61; geometric mean, 95% confidence interval; 1,3-butadiene) to 7.09 (5.88–8.54; acrylonitrile). Metabolites of acrylamide [fold difference of 1.21 (1.03–1.43)] and benzene [1.46 (1.13–1.90)] were higher during vaping compared with abstention. The 1,3-butadiene and propylene oxide metabolites were higher in variable-power tank users compared with users of cig-a-likes. E-cigarettes expose users to lower levels of toxic VOCs compared with cigarette smoking, supporting their harm reduction potential among smokers. However, some e-cigarettes expose users to VOCs such as acrylamide, benzene, and propylene oxide, and may pose health risks to nonsmoking users. The results of our study will inform regulators in assessing e-cigarettes with respect to the balance between its potential harm reduction for adult smokers and risk to nonsmoking users.

Background: We examined the nicotine metabolite ratio's (NMR) relationship with smoking intensity, nicotine dependence, and a broad array of biomarkers of exposure and biological effect in commercial cigarette smokers. Methods: Secondary analysis was conducted on two cross-sectional samples of adult, daily smokers from Wave 1 (2013–2014) of the Population Assessment of Tobacco Use and Health (PATH) Study and baseline data from a 2014–2017 randomized clinical trial. Data were restricted to participants of non-Hispanic, white race. The lowest quartile of NMR ( Results: Compared with slow metabolizers, normal/fast metabolizers had greater cigarettes per day and higher levels of total nicotine equivalents, tobacco-specific nitrosamines, volatile organic componds, and polycyclic aromatic hydrocarbons. A novel finding was higher levels of inflammatory biomarkers among normal/fast metabolizers versus slow metabolizers. With NMR modeled as a continuous measure, the associations between NMR and biomarkers of inflammation were not significant. Conclusions: The results are suggestive that normal/fast nicotine metabolizers may be at increased risk for tobacco-related disease due to being heavier smokers, having higher exposure to numerous toxicants and carcinogens, and having higher levels of inflammation when compared with slow metabolizers. Impact: This is the first documentation that NMR is not only associated with smoking exposure but also biomarkers of biological effects that are integral in the development of tobacco-related disease. Results provide support for NMR as a biomarker for understanding a smoker's exposure and potential risk for tobacco-related disease.

BACKGROUND: Pre-treatment factors that increase smokers’ risk of experiencing neuropsychiatric adverse events (NPSAEs) when quitting smoking are unknown. OBJECTIVE: To identify baseline smoker characteristics beyond the history of mental illness that predict which participants were more likely to experience moderate to severe NPSAEs in EAGLES. DESIGN: A prospective correlational cohort study in the context of a multinational, multicenter, double-blind, randomized trial. PARTICIPANTS: Smokers without (N = 3984; NPC)/with (N = 4050; PC) histories of, or current clinically stable, psychiatric disorders including mood (N = 2882; 71%), anxiety (N = 782; 19%), and psychotic (N = 386; 10%) disorders. INTERVENTIONS: Bupropion, 150 mg twice daily, or varenicline, 1 mg twice daily, versus active control (nicotine patch, 21 mg/day with taper) and placebo for 12 weeks with 12-week non-treatment follow-up. MAIN MEASURES: Primary safety outcome was the incidence of a composite measure of moderate/severe NPSAEs. Associations among baseline demographic/clinical characteristics and the primary safety endpoint were analyzed post hoc via generalized linear regression. KEY RESULTS: The incidence of moderate to severe NPSAEs was higher among smokers in the PC (238/4050; 5.9%) than in the NPC (84/3984; 2.1%). Three baseline characteristics predicted increased risk for experiencing clinically significant NPSAEs when quitting regardless of carrying a psychiatric diagnosis: current symptoms of anxiety (for every ~ 4-unit increase in HADS anxiety score, the absolute risk of occurrence of the NPSAE endpoint increased by 1% in both PC and NPC); prior history of suicidal ideation and/or behavior (PC, 4.4% increase; P = 0.001; NPC, 4.1% increase; P = 0.02), and being of White race (versus Black: PC, 2.9% ± 0.9 [SE] increase; P = 0.002; and NPC, 3.4% ± 0.8 [SE] increase; P = 0.001). Among smokers with psychiatric disorders, younger age, female sex, history of substance use disorders, and proxy measures of nicotine dependence or psychiatric illness severity also predicted greater risk. There were no significant interactions between these characteristics and treatment. Smokers with unstable psychiatric disorders or with current, active substance abuse were excluded from the study. CONCLUSIONS: Irrespective of cessation pharmacotherapy use, smokers attempting to quit were more likely to experience moderate to severe NPSAEs if they reported current anxiety or prior suicidal ideation at baseline and were White. In smokers with a psychiatric history, female sex, younger age, and greater severity of nicotine dependence were also predictive. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01456936

Objective The study objective was to identify biobehavioral variables associated with greater intake of nicotine and a tobacco carcinogen among Black light smokers who smoke 1 to 10 cigarettes per day (CPD). Methods We analyzed baseline data collected from 426 Black light smokers enrolled in Kick It at Swope III (KIS III), a smoking cessation trial for Black smokers. We examined differences in concentrations of tobacco biomarkers, including urinary total nicotine equivalents (TNE) and total 4-(methylnitrosamino)-1-(3)pyridyl-1-butanonol (NNAL; a human carcinogen), across gender, age, plasma nicotine metabolite ratio (NMR), CPD, and measures of tobacco dependence, including time to first cigarette (TFC), using ANOVA. Results Tobacco biomarker levels were significantly higher among those who smoked more CPD (6–10 vs 1–5 CPD) and those with greater reported physical dependence on tobacco. Concurrently, those who smoked 1–5 CPD smoked each cigarette more intensely than those who smoked 6–10 CPD. While we found no gender differences overall, among those who smoked 1–5 CPD, women had higher NNAL levels compared to men. The rate of nicotine metabolism, measured by the nicotine metabolite ratio, was not significantly related to TNE or NNAL levels. Conclusion Among Black Light smokers, higher cigarette consumption and greater physical dependence—but not rate of nicotine metabolism, menthol use, or socioeconomic status—were associated with greater toxicant exposure and thus a likely increased risk of tobacco-related diseases. The lack of data on light smokers, and specifically on Blacks, make this observation important given the disproportionate burden of lung cancer in this population.

BackgroundThe changing prevalence and patterns of tobacco use, the advent of novel nicotine delivery devices, and the development of new biomarkers prompted an update of the 2002 Society for Research on Nicotine and Tobacco (SRNT) report on whether and how to apply biomarker verification for tobacco use and abstinence.MethodsThe SRNT Treatment Research Network convened a group of investigators with expertise in tobacco biomarkers to update the recommendations of the 2002 SNRT Biochemical Verification Report.ResultsBiochemical verification of tobacco use and abstinence increases scientific rigor and is recommended in clinical trials of smoking cessation, when feasible. Sources, appropriate biospecimens, cutpoints, time of detection windows and analytic methods for carbon monoxide, cotinine (including over the counter tests), total nicotine equivalents, minor tobacco alkaloids, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol are reviewed, as well as biochemical approaches to distinguishing cigarette smoking from use of electronic nicotine delivery devices (ENDS).ConclusionsRecommendations are provided for whether and how to use biochemical verification of tobacco use and abstinence. Guidelines are provided on which biomarkers to use, which biospecimens to use, optimal cutpoints, time windows to detection, and methodology for biochemical verifications. Use of combinations of biomarkers is recommended for assessment of ENDS use.ImplicationsBiochemical verification increases scientific rigor, but there are drawbacks that need to be assessed to determine whether the benefits of biochemical verification outweigh the costs, including the cost of the assays, the feasibility of sample collection, the ability to draw clear conclusions based on the duration of abstinence, and the variability of the assay within the study population. This paper provides updated recommendations from the 2002 SRNT report on whether and how to use biochemical markers in determining tobacco use and abstinence.

Author(s): Patten, Christi A; Koller, Kathryn R; Flanagan, Christie A; Hiratsuka, Vanessa Y; Hughes, Christine A; Wolfe, Abbie W; Decker, Paul A; Fruth, Kristin; Brockman, Tabetha A; Korpela, Molly; Gamez, Diana; Bronars, Carrie; Murphy, Neil J; Hatsukami, Dorothy; Benowitz, Neal L; Thomas, Timothy K | Abstract: ObjectiveThere is some evidence for biomarker feedback when combined with cessation counseling for reducing smoking in pregnancy. This randomized controlled pilot study evaluated feasibility and potential efficacy of a social-cognitive theory (SCT)-based biomarker feedback intervention among pregnant Alaska Native (AN) smokers.MethodsParticipants were randomly assigned to receive three study calls (10-20 min each): (1) biomarker feedback intervention (n = 30) including personalized cotinine results and feedback on their baby's likely exposure to carcinogen metabolite NNAL, or (2) contact control usual care condition based on the 5As (n = 30). Assessments were conducted at baseline, post-treatment, and delivery.ResultsHigh rates of treatment compliance, study retention, and treatment acceptability were observed in both groups. 7-day point prevalence smoking abstinence rates at delivery verified with urinary cotinine were the same in both study groups (20% intent-to-treat analysis, 26% per-protocol). SCT-based measures did not change differentially from baseline by study group.ConclusionThis trial supports the feasibility and acceptability of providing biomarker feedback within the clinical care delivery system, but the intervention did not promote increased smoking cessation during pregnancy compared to usual care.Practice implicationsEfforts are needed to promote the usual care and to develop alternative biomarker feedback messaging for pregnant AN women.

Author(s): Evins, A Eden; Benowitz, Neal L; West, Robert; Russ, Cristina; McRae, Thomas; Lawrence, David; Krishen, Alok; St Aubin, Lisa; Maravic, Melissa Culhane; Anthenelli, Robert M | Abstract: BACKGROUND:Neuropsychiatric safety and relative efficacy of varenicline, bupropion, and transdermal nicotine patch (NRT) in those with psychiatric disorders are of interest. METHODS:We performed secondary analyses of safety and efficacy outcomes by psychiatric diagnosis in EAGLES (Evaluating Adverse Events in a Global Smoking Cessation Study), a 12-week, randomized, double-blind, triple-dummy, placebo- and active (NRT)-controlled trial of varenicline and bupropion with 12-week follow-up, in a subset population, n = 4092, with a primary psychotic (n = 390), anxiety (n = 792), or mood (n = 2910) disorder. Primary end-point parameters were incidence of prespecified moderate and severe neuropsychiatric adverse events (NPSAEs) and weeks 9 to 12 continuous abstinence rates (9-12CAR). RESULTS:The observed NPSAE incidence across treatments was 5.1% to 6.3% in those with a psychotic disorder, 4.6% to 8.0% in those with an anxiety disorder, and 4.6% to 6.8% in those with a mood disorder. Neither varenicline nor bupropion was associated with significantly increased NPSAEs relative to NRT or placebo in the psychiatric cohort or any psychiatric diagnostic subcohort. There was a significant effect of treatment on 9-12CAR (P l 0.0001) and no significant treatment-by-diagnostic subcohort interaction (P = 0.24). Abstinence rates with varenicline were superior to bupropion, NRT, and placebo, and abstinence with bupropion and NRT was superior to placebo. Within-diagnostic subcohort comparisons of treatment efficacy yielded estimated odds ratios for 9-12CAR versus placebo of greater than 3.00 for varenicline, greater than 1.90 for bupropion, and greater than 1.80 for NRT for all diagnostic groups. CONCLUSIONS:Varenicline, bupropion, and nicotine patch are well tolerated and effective in adults with psychotic, anxiety, and mood disorders. The relative effectiveness of varenicline, bupropion, and NRT versus placebo did not vary across psychiatric diagnoses.

The nicotine metabolite ratio (NMR; 3-hydroxycotinine/cotinine) is an index of CYP2A6 activity. CYP2A6 is responsible for nicotine’s metabolic inactivation and variation in the NMR/CYP2A6 is associated with several smoking behaviors. Our aim was to integrate established alleles and novel genome-wide association studies (GWAS) signals to create a weighted genetic risk score (wGRS) for the CYP2A6 gene for European-ancestry populations. The wGRS was compared with a previous CYP2A6 gene scoring approach designed for an alternative phenotype (C2/N2; cotinine-d2/(nicotine-d2 + cotinine-d2)). CYP2A6 genotypes and the NMR were assessed in European-ancestry participants. The wGRS training set included N = 933 smokers recruited to the Pharmacogenetics of Nicotine Addiction and Treatment clinical trial [NCT01314001]. The replication cohort included N = 196 smokers recruited to the Quit 2 Live clinical trial [NCT01836276]. Comparisons between the two CYP2A6 phenotypes and with fractional clearance were made in a laboratory-based pharmacokinetic study (N = 92 participants). In both the training and replication sets, the wGRS, which included seven CYP2A6 variants, explained 33.8% (P < 0.001) of the variance in NMR, providing improved predictive power to the NMR phenotype when compared with other CYP2A6 gene scoring approaches. NMR and C2/N2 were strongly correlated to nicotine clearance (ρ = 0.70 and ρ = 0.79, respectively; P < 0.001), and to one another (ρ = 0.82; P < 0.001); however reduced function genotypes occurred in slow NMR but throughout C2/N2. The wGRS was able to predict smoking quantity and nicotine intake, to discriminate between NMR slow and normal metabolizers (AUC = 0.79; P < 0.001), and to replicate previous NMR-stratified cessation outcomes showing unique treatment outcomes between metabolizer groups. CLINICAL TRIAL REGISTRATIONS: NCT01314001 and NCT01836276.

Smokers attempting to quit often attribute smoking relapse to negative affect, craving, and other nicotine withdrawal symptoms. In addition, there is evidence that smoking relapse can increase these symptoms, particularly negative affect. To address this issue, we analyzed data from an 11-week smoking cessation clinical trial in which smokers (n = 1,246) were randomized to receive either nicotine replacement therapy (NRT), varenicline, or placebo, combined with behavioral counseling. Using cross-lagged analyses, we examined the temporal bidirectional relationships between self-reported measures of affect, craving, and composite withdrawal symptoms and biochemically verified smoking abstinence. The relative strength of these temporal relationships was examined by comparing the explained variances of the models. The results showed that higher negative affect, craving, and composite withdrawal symptoms increased the likelihood of subsequent smoking relapse, and that smoking relapse led to subsequent increases in these same symptoms. A comparison of the explained variances found symptom predicting subsequent relapse models to be stronger than those where relapse predicted subsequent symptoms. Although the explained variance findings generally support a negative reinforcement conceptualization of nicotine dependence, the bidirectional relationship between symptoms and smoking relapse suggests that struggling with quitting smoking leads to significant negative affect, craving, and other withdrawal symptoms that do not quickly resolve. These findings highlight the importance of addressing specific symptoms within the context of smoking cessation. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The urinary metabolites cyanoethyl mercapturic acid (CEMA) and 3-hydroxypropyl mercapturic acid (3-HPMA) have been widely used as biomarkers of exposure to acrylonitrile and acrolein, respectively, but there are no published data on their consistency over time in the urine of cigarette smokers. We provided, free of charge over a 20 week period, Spectrum NRC600/601 research cigarettes to cigarette smokers in the control arm of a randomized clinical trial of the reduced nicotine cigarette. Urine samples were collected at weeks 4, 8, 12, 16, and 20 and analyzed for CEMA and 3-HPMA, and total nicotine equivalents (TNE) using validated methods. Creatinine-corrected intra-class correlation coefficients for CEMA, 3-HPMA, and TNE were 0.67, 0.46, and 0.68, respectively, indicating good longitudinal consistency for CEMA, while that of 3-HPMA was fair. A strong correlation between CEMA and TNE values was observed. These data support the use of CEMA as a reliable biomarker of tobacco smoke exposure. This is the first report of the longitudinal stability of the biomarkers of acrylonitrile and acrolein exposure in smokers. The data indicate that CEMA, the biomarker of acrylonitrile exposure, is consistent over time in cigarette smokers, supporting its use. While 3-HPMA levels were less stable over time, this biomarker is nevertheless a useful monitor of human acrolein exposure because of its specificity to this toxicant.