650 research outputs found
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The Role of Compensation in Nicotine Reduction.
The available research on switching from normal nicotine to very low nicotine content cigarettes shows minimal evidence of compensatory smoking. Mathematical estimations suggest that substantial compensation after switching to very low nicotine cigarettes would be impossible. It is likely that smokers who are unable to tolerate the extent of proposed nicotine reduction would switch to other sources of nicotine, rather than try to compensate by smoking more very low nicotine content cigarettes more intensely
Influence of menthol on caffeine disposition and pharmacodynamics in healthy female volunteers
Objectives: The present study was undertaken to determine whether a single oral dose of menthol affects the metabolism of caffeine, a cytochrome P 450 1A2 (CYP1A2) substrate, and pharmacological responses to caffeine in people. Methods: Eleven healthy female subjects participated in a randomized, double-blind, two-way crossover study, comparing the kinetics and effects of a single oral dose of caffeine (200 mg) in coffee taken together with a single oral dose of menthol (100 mg) or placebo capsules. Serum caffeine concentrations and cardiovascular and subjective parameters were measured throughout the study. Results: Co-administration of menthol resulted in an increase of caffeine tmax values from 43.6 ± 20.6 min (mean ± SD) to 76.4 ± 28.0 min (P<0.05). The Cmax values of caffeine were lower in the menthol phase than in the placebo phase, but this effect was not statistically significant (P=0.06). (AUG)0-24, (AUC)0-∞, terminal half-life and oral clearance were not affected by menthol. Only nine subjects' cardiovascular data were included in the analysis because of technical problems during the measurements. After caffeine, heart rate decreased in both treatment phases. The maximum decrease in heart rate was less in the menthol phase (-8.9 ± 3.9 beats/min) than in the placebo phase (-13.1 ± 2.1 beats/min) (P = 0.024). There were no statistically significant differences in systolic and diastolic blood pressures between the two treatments. Conclusions: We conclude that a single oral dose of pure menthol (100 mg) delays caffeine absorption and blunts the heart-rate slowing effect of caffeine, but does not affect caffeine metabolism. The possibility that menthol slows the absorption of other drugs should be considered.Dokuz Eylul University Research Foundation (project no: 0909.99.02.16
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Biomarkers of Toxic Exposure and Oxidative Stress Among U.S. Adult Users of Premium Cigar Versus Other Cigar Subtypes: 2013-2019
INTRODUCTION: Cigars are currently the second-highest-used combustible tobacco product among U.S. adults, but knowledge about health effects of premium cigars versus other cigar subtype use is limited.
AIMS AND METHODS: This study analyzed the biospecimen data (n = 31 875) from Waves 1-5 of the Population Assessment of Tobacco and Health Study, collected during 2013-2019. Multivariable generalized estimation equations, accounting for within-person clustering, were conducted to examine differences in urine biomarkers of exposure (BOE) from five classes of harmful and potentially harmful constituents along with a biomarker of oxidative stress (urine 8-isoprostane) among exclusive users of premium cigars versus other exclusive cigar subtypes (ie, non-premium large cigars, cigarillos, and filtered cigars), cigarettes, and non-tobacco users.
RESULTS: In comparison to non-tobacco users, exclusive premium cigar users had higher geometric mean concentrations of the nicotine metabolite cotinine (5.8 vs. 0.5ng/mg, p \u3c .0001), tobacco-specific nitrosamine (TSNA) (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL): 7.8 vs. 1.3pg/mg, p \u3c .0001), and volatile organic compound (VOC) (N-Acetyl-S-(2-cyanoethyl)-L-cysteine (CYMA, acrylonitrile): 4.7 vs. 1.6ng/mg, p \u3c .0001). Exclusive premium cigar users were less likely to be daily users than other tobacco user groups and had comparable BOEs with exclusive non-premium large cigar users but generally lower BOEs than exclusive cigarillo, filtered cigar, and cigarette smokers. Daily exclusive premium cigar users had similar nicotine and TSNA exposure but lower exposure to polycyclic aromatic hydrocarbons and volatile organic compounds than exclusive cigarillo and filtered cigar users.
CONCLUSIONS: Premium cigar use exhibits different exposure to toxicants from other cigar subtype users. Regulations of premium cigars need to formalize product definition and take the population\u27s health effects into consideration.
IMPLICATIONS: This population study provides important information on BOE and potential harm with premium cigar use and its potential health effects. At present, premium cigars appear to pose a relatively low overall population health risk due to low frequency of use. However, future regulation of other tobacco products might change the landscape of premium cigar use and alter the overall health impact
Exposure to Toxicants Associated With Use and Transitions Between Cigarettes, e-Cigarettes, and No Tobacco
Importance: Transitions between e-cigarettes and cigarettes are common among tobacco users, but empirical evidence on the health outcomes of switching tobacco products is scarce.
Objectives: To examine changes in urinary biomarkers between baseline and 1-year follow-up among adult tobacco users switching between e-cigarettes and cigarettes.
Design, Setting, and Participants: This cohort study used data from wave 1 (baseline, September 2013 to December 2014) and wave 2 (1-year follow-up, October 2014 to October 2015) of the Population Assessment of Tobacco and Health Study. A subset of the probability sample of US adults who voluntarily provided biospecimens at 2 waves was analyzed. Participants were divided into 3 mutually exclusive groups at baseline: exclusive cigarette smokers, exclusive e-cigarette users, and dual users. Data analysis was performed in 2021.
Exposures: Harmful and potentially harmful constituents included nicotine metabolites, tobacco-specific nitrosamines (TSNAs; including 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol [NNAL]), metals, polycyclic aromatic hydrocarbons (PAHs), and volatile organic compounds (VOCs).
Main Outcomes and Measures: Within-participant changes in 55 urinary biomarkers of exposure (BOEs) to harmful and potentially harmful constituents were examined using multivariable regression models.
Results: Among 3211 participants (55.6% women, 68.3% White, 13.2% Black, and 11.8% Hispanic) at baseline, 21.9% of exclusive cigarette users, 42.8% of exclusive e-cigarette users, and 62.1% of dual users changed product use at follow-up (all percentages are weighted). There was a significant reduction in urine concentrations of TSNAs, PAHs, and VOCs when users transitioned from exclusive cigarette to exclusive e-cigarette use, with a 92% decrease in NNAL, from a mean of 168.4 pg/mg creatinine (95% CI, 102.3-277.1 pg/mg creatinine) to 12.9 pg/mg creatinine (95% CI, 6.4-25.7 pg/mg creatinine; P \u3c .001). A similar panel of BOEs decreased when dual users transitioned to exclusive e-cigarette use; NNAL levels decreased by 96%, from a mean of 143.4 pg/mg creatinine (95% CI, 86.7-237.0 pg/mg creatinine) to 6.3 pg/mg creatinine (95% CI, 3.5-11.4 pg/mg creatinine; P \u3c .001). Nicotine metabolites, TSNAs, PAHs, and VOCs significantly increased when baseline exclusive e-cigarette users transitioned to exclusive cigarette use or dual use. Switching from exclusive cigarette use to dual use was not associated with significant decreases in BOEs.
Conclusions and Relevance: This national cohort study provides evidence on the potential harm reduction associated with transitioning from exclusive cigarette use or dual use to exclusive e-cigarette use. e-Cigarettes tend to supplement cigarettes through dual use instead of cessation at the population level. Continuous monitoring of BOE at the population level and assessment of BOE change by product transition are warranted, as well as defined adverse health outcomes
Society for Research on Nicotine and Tobacco
The proceedings of the inaugural scientific meeting of the Society for Research on Nicotine and Tobacco (SRNT) are summarized. The primary objective of the meeting was to foster the exchange of information on the effects of nicotine and tobacco use, as well as factors which influence their use, drawing from biological, behavioral and social sciences. Much of this research can be viewed as a tale of two drugs nicotine as a key to an important public health problem, and nicotine as a classical tool of physiological and pharmacological research. A historical overview of research on both drugs is provided first. Public policy alternatives for reducing the prevalence of tobacco use have been derived in part from basic and clinical research results and are briefly outlined. Evidence for genetic determinants on nicotine use and effects is presented using data from twin studies and from molecular genetic research with humans and animals. Consistent with this research, there is evidence of individual differences in pharmacokinetics and effects of nicotine, which could account for differences in smoking behavior and nicotine dependence. Finally, recent developments in the therapeutic uses of nicotine and novel nicotinic agonists with schizophrenia, Alzheimer's disease, Parkinson's disease, Tourette's syndrome and ulcerative colitis are presented. Overall, the research presented at the meeting demonstrated the vast diversity of areas of study involving nicotine and tobacco, as well as the rich opportunities for cross-communication among researchers from different disciplines.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72963/1/j.1360-0443.1996.91112915.x.pd
Comprehensive Parent-Metabolite PBPK/PD Modeling Insights into Nicotine Replacement Therapy Strategies
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 profles and 11 heart rate profles. 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 profles. 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 diferences 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 frst nicotine PBPK/PD model predicting nicotine concentration and heart rate profles
after the use of e-cigarettes, it could also contribute to a better understanding of the recent increase in youth e-cigarette use
Chinese ‘low-tar’ cigarettes do not deliver lower levels of nicotine and carcinogens
BackgroundLow-tar cigarette smoking is gaining popularity in China. The China National Tobacco Corporation (CNTC) promotes low-tar cigarettes as safer than regular cigarettes.MethodsA total of 543 male smokers smoking cigarettes with different tar yields (15 mg, regular cigarettes, 10-13 mg low-tar cigarettes and < 10 mg low-tar cigarettes) were recruited in Shanghai, China, who then completed a questionnaire on smoking behaviour and provided a urine sample for analysis of the nicotine metabolites cotinine and trans-3'-hydroxycotinine. A total of 177 urine samples were selected at random for the analysis of the carcinogens polycyclic aromatic hydrocarbon metabolites (PAHs) (1-hydroxypyrene, naphthols, hydroxyfluorenes and hydroxyphenanthrenes) and the tobacco specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-butanone (NNK) metabolites, 4-(methylnitrosamino)-1-(3-pyridyl)-butanol (NNAL) and NNAL-glucuronide. Values were normalised by creatinine to correct for possible distortions introduced by dilution or concentration of the urine.ResultsSmokers of low-tar cigarettes smoked fewer cigarettes per day (p=0.001) compared to smokers of regular cigarettes. Despite this lower reported consumption, levels of cotinine, trans-3'-hydroxycotinine and PAHs in urine of people smoking low-tar cigarettes were not correlated with nominal tar delivery of the cigarettes they smoked. Urine concentrations of NNAL were higher in smokers of lower tar than higher tar cigarettes.ConclusionsChinese low-tar cigarettes do not deliver lower doses of nicotine and carcinogens than regular cigarettes, therefore it is unlikely that there would be any reduction in harm. CNTC's promotion of low-tar cigarettes as 'less harmful' is a violation of the World Health Organization Framework Convention on Tobacco Control, which China ratified in 2005
Determinantes dos nÃveis de cotinina salivar: um estudo de base populacional no Brasil
OBJECTIVE: A cross-sectional population-based study was conducted to assess, in active smokers, the relationship of number of cigarettes smoked and other characteristics to salivary cotinine concentrations. METHODS: A random sample of active smokers aged 15 years or older was selected using a stepwise cluster sample strategy, in the year 2000 in Rio de Janeiro, Brazil. The study included 401 subjects. Salivary cotinine concentration was determined using gas chromatography with nitrogen-phosphorus detection. A standard questionnaire was used to collect demographic and smoking behavioral data. The relation between the number of cigarettes smoked in the last 24h and cotinine level was examined by means of a nonparametric fitting technique of robust locally weighted regression. RESULTS: Significantly (p;40 ng/mL per cigarette were excluded. CONCLUSIONS: There was found a positive association between self-reporting smoking five minutes after waking up, and inhaling more than ½ the time are consistent and higher cotinine levels. These can be markers of dependence and higher nicotine intake. Salivary cotinine proved to be a useful biomarker of recent smoking and can be used in epidemiological studies and smoking cessation programs.OBJETIVO: Realizou-se um estudo transversal para analisar a relação entre número de cigarros fumados e outras caracterÃsticas com a concentração de cotinina salivar entre fumantes. MÉTODOS: Fumantes ativos de 15 anos ou mais foram selecionados por meio de amostra probabilÃstica em múltiplos estágios no ano 2000, municÃpio do Rio de Janeiro, Brasil. O estudo incluiu 401 fumantes. A concentração de cotinina salivar foi determinada utilizando-se cromatografia gasosa com detector de nitrogênio/fósforo. Coletaram-se informações demográficas e sobre o comportamento tabágico utilizando-se questionário padronizado. A relação entre o número de cigarros fumados nas últimas 24h e o nÃvel de cotinina foi analisada utilizando técnica não paramétrica baseada em regressões robustas locais ponderadas. RESULTADOS: O nÃvel médio ajustado de cotinina foi significativamente (
Directly measured secondhand smoke exposure and COPD health outcomes
BACKGROUND: Although personal cigarette smoking is the most important cause and modulator of chronic obstructive pulmonary disease (COPD), secondhand smoke (SHS) exposure could influence the course of the disease. Despite the importance of this question, the impact of SHS exposure on COPD health outcomes remains unknown. METHODS: We used data from two waves of a population-based multiwave U.S. cohort study of adults with COPD. 77 non-smoking respondents with a diagnosis of COPD completed direct SHS monitoring based on urine cotinine and a personal badge that measures nicotine. We evaluated the longitudinal impact of SHS exposure on validated measures of COPD severity, physical health status, quality of life (QOL), and dyspnea measured at one year follow-up. RESULTS: The highest level of SHS exposure, as measured by urine cotinine, was cross-sectionally associated with poorer COPD severity (mean score increment 4.7 pts; 95% CI 0.6 to 8.9) and dyspnea (1.0 pts; 95% CI 0.4 to 1.7) after controlling for covariates. In longitudinal analysis, the highest level of baseline cotinine was associated with worse COPD severity (4.7 points; 95% CI -0.1 to 9.4; p = 0.054), disease-specific QOL (2.9 pts; -0.16 to 5.9; p = 0.063), and dyspnea (0.9 pts; 95% CI 0.2 to 1.6 pts; p < 0.05), although the confidence intervals did not always exclude the no effect level. CONCLUSION: Directly measured SHS exposure appears to adversely influence health outcomes in COPD, independent of personal smoking. Because SHS is a modifiable risk factor, clinicians should assess SHS exposure in their patients and counsel its avoidance. In public health terms, the effects of SHS exposure on this vulnerable subpopulation provide a further rationale for laws prohibiting public smoking
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