Treatment of tobacco dependence

Anesthesiologists and the Other Pandemic: Tobacco Use

Tobacco use will kill a projected 1 billion people in the 21st century in one of the deadliest pandemics in history. Tobacco use disorder is a disease with a natural history, pathophysiology, and effective treatment options. Anesthesiologists can play a unique role in fighting this pandemic, providing both immediate (reduction in perioperative risk) and long-term (reduction in tobacco-related diseases) benefits to their patients who are its victims. Receiving surgery is one of the most powerful stimuli to quit tobacco. Tobacco treatments that combine counseling and pharmacotherapy (e.g., nicotine replacement therapy) can further increase quit rates and reduce risk of morbidity such as pulmonary and wound-related complications. The perioperative setting provides a great opportunity to implement multimodal perianesthesia tobacco treatment, which combines multiple evidence-based tactics to implement the four core components of consistent ascertainment and documentation of tobacco use, advice to quit, access to pharmacotherapy, and referral to counseling resources.

The Impact of Psychiatric Disorder Diagnosis on Motivation to Quit and Stage of Change Among Patients at a Hospital-Based Outpatient Smoking Cessation Clinic

Smoking is among the greatest international public health concerns, causing excessive levels of preventable premature death, disability, and economic costs. The prevalence of tobacco use among people with psychiatric disorders (PDs) remains persistently high relative to the general population, highlighting the need to improve smoking cessation (SC) strategies in this group. We aimed to assess the associations between having a PD and baseline motivation to quit (MtQ) smoking and Prochaska's stage of change (SoC), two clinically important metrics linked to SC outcomes. Methods: This retrospective chart review included patients who completed a baseline visit at a hospital-based outpatient SC clinic (N = 896). Multivariate hierarchical logistic and linear regression models were developed to assess variables associated with MtQ (importance and confidence in quitting) and SoC, primarily PD category (externalizing, internalizing, externalizing/internalizing, psychotic or no PD) and secondarily, demographics, physical health history, and tobacco use/dependence metrics. Results: The variables negatively associated with MtQ were female sex (p = .011), older age (p = .038), deriving income from social assistance (p < .001), and age at smoking initiation (p = .005), whereas ≥ 1 quit attempt in the past year predicted higher MtQ (p < .0001). Being in the preparative/action SoC (versus the pre-contemplative/contemplative) was associated with income from social assistance (OR 0.39, p = .001), more daily cigarettes smoked (OR 0.98, p = .005) and ≥ 1 past-year quit attempt (OR 1.69, p = .013). Conclusions: Having a PD was not associated with either MtQ or SoC. Deriving income from social assistance predicted lower MtQ and SoC. Having made ≥ 1 quit attempt in the past year was associated with higher MtQ and SoC. Our study suggests that people with PDs are as motivated to quit smoking and ready for change as people without PDs, and smoking cessation efforts should be amplified in this group to address the disproportionately high level of tobacco use, especially because having at least one quit attempt may enhance MtQ and SoC.

Factors associated with tobacco cessation attempts among inpatients in a psychiatric hospital

Introduction

Several effective evidence-based tobacco treatment approaches can optimize cessation attempts; however, little is known about the utilization of such strategies by people with mental illnesses (MI) during their cessation attempts.

Aims

To examine methods used during and factors associated with tobacco cessation attempts among people with MI.

Methods

Self-administered cross-sectional survey data were obtained from 132 tobacco using inpatients from a psychiatric facility in Kentucky, USA.

Results

Our study found ‘cold turkey’ as the most reported method by inpatient tobacco users with MI in their prior cessation attempts regardless of the psychiatric diagnosis category. Multivariate logistic regression found ethnicity (OR 26.1; 95% CI 2.9–237.1), age at 1st smoke (OR 1.1; 95% CI 1.0–1.1), importance to quit (OR 1.2; 95% CI 1.0–1.4), and receipt of brief tobacco treatment interventions (OR 1.1; 95% CI 1.0–1.3) significantly associated with quit attempt in the past year.

Conclusion

Despite the existence of various evidence-based approaches to enhance tobacco cessation among people with MI, ‘cold-turkey’ was the most preferred method in this sample. In addition, this study highlighted ethnicity, importance to quit, age at 1st smoke, and receipt of brief interventions as important factors to consider when tailoring tobacco cessation in this population. Though ethnicity is a non-modifiable factor, an informed provider may intervene skillfully by addressing socio-cultural barriers specific to an ethnic group. Lower ratings on the motivation ruler and early age of smoking initiation could also inform providers when using motivational interviewing and other evidence-based tobacco-cessation approaches.

Impact of a Smoking Cessation Quitline in Vietnam: Evidence Base and Future Directions

Smoking is considered the most critical modifiable factor with regard to lung cancer and remains a public health concern in many countries, including Vietnam, which is among those countries with the highest tobacco consumption rates in the world. This study has examined the impact of national telephone counselling for smoking cessation and has identified the factors associated with the impact of the quitline among male callers in Vietnam. A randomized cross-sectional survey of 469 smokers who sought smoking cessation services via the national quitline was performed from September 2015 to May 2016. The primary outcomes were measured by a self-reported quit rate at the time of assessment, 7 day point prevalence abstinence (PA), 6 month prolonged PA, service satisfaction, and level of motivation. Among the participants, 31.6% were abstinent, and 5.1% of participants successfully stopped smoking and did not need to seek quitline support. Most of the clients were satisfied with the quality of service (88.5%), felt more confident about quitting (74.3%), and took early action via their first quit attempt (81.7%); 18.3% reported a more than 7 day abstinence period at the time of survey. The primary reasons for smoking relapse were surrounding smoking environments (51.6%) and craving symptoms (44.1%). Future smoking cessation efforts should focus on improving the quality of quitline services, client satisfaction, and developing a tailored program and counseling targeting smokers with specific characteristics, especially ones experiencing chronic diseases.

Correlated Factors with Quitting Attempts Among Male Smokers in Vietnam: A QUITLINE-Based Survey

Despite its decreasing prevalence, cigarette smoking remains the second leading cause of preventable death worldwide. In Vietnam, despite recent smoking cessation efforts, the prevalence of tobacco consumption remains high, particularly among males. In this study, we aim to evaluate the self-efficacy in quitting smoking (i.e., quitting confidence), intention to quit, and identifying associated factors among both rural and urban Vietnamese male populations. A cross-sectional study was conducted on 321 patients (52.7% urban and 47.4% rural inhabitants) who utilized QUITLINE services of Bach Mai Hospital (Hanoi, Vietnam). Socio-economic status, smoking history, cigarette usage data, and intent to quit were assessed. Baseline data were correlated with quitting confidence, to identify significant associated factors. The majority (75.9%) of participants were in the planning phase of cessation, yet 90.8% lacked complete confidence in their quitting ability. Older age, fewer cigarettes per day and previous quitting attempts were associated with quitting confidence (p < 0.05) and plans to quit (p < 0.05). Older smokers and previous quitters were more confident in their ability to quit in the near future and more likely to have made plans to quit. Future smoking cessation efforts should focus on improving self-efficacy, particularly among younger and newer smokers.

Effect of Long-term Nicotine Replacement Therapy vs Standard Smoking Cessation for Smokers With Chronic Lung Disease: A Randomized Clinical Trial

IMPORTANCE

Smokers with chronic obstructive pulmonary disease (COPD) have particular difficulty quitting. Long-term nicotine replacement therapy (LT-NRT) might offer a strategy for reducing harm from cigarettes and provide a pathway for later cessation.

OBJECTIVE

To compare the effect of LT-NRT vs standard smoking cessation (SSC) on exposure to cigarette smoke, harm related to smoking, and cessation among smokers with COPD.

DESIGN, SETTING, AND PARTICIPANTS

This unblinded, randomized clinical trial recruited smokers who self-reported a diagnosis of COPD at any level of readiness to quit from May 23, 2014, through November 30, 2015. The 12-month follow-up was completed December 6, 2016. Patients were recruited at a clinical research unit of an academic medical center. Analysis was based on intention to treat and performed from March 8 through November 30, 2017.

INTERVENTIONS

Standard smoking cessation treatment included 10 weeks of NRT and 4 follow-up counseling sessions for those willing to make a quit attempt. Long-term NRT included 12 months of NRT and 6 follow-up counseling sessions regardless of initial willingness to quit. Overall, 198 patients were randomized to SSC, and 197 were included in the primary analysis; 200 patients were randomized to LT-NRT, and 197 were included in the primary analysis.

MAIN OUTCOMES AND MEASURES

The primary outcome was 7-day abstinence verified by carbon monoxide (CO) levels at 12 months. Secondary outcomes included cigarettes smoked per day (CPD), exposure to CO, urinary excretion of 4-methylnitrosamino-1-3-pyridyl-1-butanol (NNAL) (a smoking-related carcinogen), and adverse events.

RESULTS

Among 398 patients who were randomized (59.8% female; mean [SD] age, 56.0 [9.3] years), the mean (SD) CPD was 23.1 (12.3). Twelve-month follow-up was completed by 373 participants (93.7%), and 394 (99.0%) were included in the primary analysis. At 12 months, CO-verified abstinence occurred in 23 of 197 participants (11.7%) in the SSC arm and 24 of 197 (12.2%) in the LT-NRT arm (risk difference, 0.5%; 95% CI, -5.9% to 6.9%). Continuing smokers in the SSC and LT-NRT arms had similar, significantly reduced harms caused by smoking, including cigarette consumption by 12.4 and 14.5 CPD, respectively, exhaled CO level by 5.5 and 7.8 ppm, respectively, and mean urinary NNAL excretion by 21.7% and 23.0%, respectively. In multivariate analyses, continuing smokers with greater adherence to NRT experienced less reduction in NNAL exposure. The frequency of major adverse cardiac events was similar in both groups.

CONCLUSIONS AND RELEVANCE

Similar rates of cessation and similar reductions in exposure to tobacco smoke resulted with LT-NRT and SSC. Among continuing smokers, ongoing use of NRT was not associated with reductions in smoke exposure.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02148445.

Associations Between Secondhand Tobacco Smoke Exposure and Nicotine Dependence and Smoking Cessation Attempts Among Adult Tobacco Users With a Psychiatric Disorder

INTRODUCTION

Secondhand smoke exposure (SHSe) is predictive of greater nicotine dependence (ND) and poor smoking cessation (SC) outcomes. SHSe and its impact on ND and SC attempts in people with psychiatric disorders (PD) remain poorly understood. Hence, the objectives of this study were to (1) quantify SHSe, (2) examine the association of SHSe with ND, and (3) assess the association between SHSe and SC among tobacco users with PD.

METHOD

A cross-sectional survey of 118 tobacco users in an inpatient psychiatric facility was conducted. Data on demographics, tobacco use and SHSe history, motivation to quit smoking, ND, and SC attempts were obtained. Participants' environmental and psychosocial sources of and perceived SHSe were described. Multivariate linear regression analyses were used to examine the associations between SHSe and ND, while logistic regression analyses were used to assess the associations between SHSe and SC.

RESULTS

The primary sources of environmental SHSe were from the car (63.6%) and home (51.7%); primary sources of psychosocial SHSe were close friends (67.8%) and parents/grandparents (65.3%); and mean perceived SHSe was 6.2 ( SD = 3.5). Although perceived SHSe was significantly associated with ND (β = .39, p < .0001) in multivariate analyses, no SHSe variable was associated with SC. However, scores on items measuring motivation to quit smoking were associated with SC attempts.

DISCUSSION

Patients with PD reported high levels of SHSe, which was associated with higher ND. Routine screening for SHSe should be implemented as part of health assessments in this population to address ND treatment options. Moreover, targeted interventions and policies should be considered toward reducing SHSe in this vulnerable population.

Risk Factor Modification Behaviors of Practicing Vascular Surgeons

BACKGROUND

National smoking rates have declined; however, it remains the primary modifiable risk factor for nearly all vascular disease. While vascular surgeons have the availability to treat patients via medical or surgical/endovascular means, involvement in risk factor modification may be lacking. This study seeks to understand vascular surgeons' involvement in tobacco cessation and risk factor modification and to determine if practice variables had any effect on provision of these services to vascular surgery patients.

METHODS

Anonymous electronic surveys examining tobacco cessation and risk factor modification were sent to the Vascular & Endovascular Surgery Society members (n = 633). Influence of time from training, practice type (dichotomized into academic and nonacademic vascular surgeons), hospital size, region, and workload was assessed, and data were analyzed by univariate contingency tables.

RESULTS

A total of 149 (24%) surveys were completed. While the majority of respondents ask patient's smoking status (97%), assess willingness to quit (84%), and advise patients to quit (95%), only 34% prescribe medications to assist in cessation, 7% see patients in tobacco cessation follow-up, and 3% verify cessation with cotinine levels or carbon monoxide monitoring. Surgeons who prescribed medications for cessation are more likely to assess patient's willingness to quit, prescribe/advise nicotine replacement, or prescribe initial statin or other lipid-lowering medications. There was no difference in perceived education received during training in risk factor modification, but only 26% of respondents thought they were well trained. Comparing academic to private practice vascular surgeons, there was no difference in cessation techniques used; however, academic surgeons were less likely to perform endovascular procedures for claudication in patients who continued to smoke (29% vs. 46%, P = 0.03) and more likely to prescribe an initial antihyperlipid medication (65% vs. 39%, P = 0.0018).

CONCLUSIONS

Tobacco dependence remains a critical issue for vascular surgery patients; however, there is wide variation in cessation techniques used. The majority of vascular surgeons are not well versed in cessation techniques and risk factor modification, and thus, efforts should be made to provide this education in vascular surgery training programs.

A Retrospective Analysis of the Outcomes of Smoking Cessation Pharmacotherapy Among Persons With Mental Health and Substance Use Disorders

OBJECTIVES

It is common practice to individualize smoking cessation pharmacotherapy based on clinical judgment and patient response. However, little has been documented about the use and outcomes of smoking cessation pharmacotherapy in real-world settings. This study examines factors associated with using smoking cessation pharmacotherapy and related outcomes among smokers with psychiatric and/or substance use disorders who completed an intensive tobacco treatment program within mental health and addiction services settings in Vancouver, Canada.

METHODS

A retrospective analysis was used to examine combined program participation data (N = 889) from two tobacco treatment programs (i.e., the Tobacco Dependence Clinic and the Butt Out group) between September 2007 and July 2013. Changes in smoking cessation pharmacotherapy from the initial to final treatment and seven-day point prevalence of smoking abstinence (verified by expired carbon monoxide) were assessed at the end of treatment.

RESULTS

During treatment, 60% of participants remained on the initial pharmacotherapy plan, 30% received adjunctive treatment, and 10% had treatment plans that were switched. Those whose pharmacotherapy was switched had higher cigarette consumption and nicotine dependence at baseline and were less likely to have a psychiatric disorder history. When comparing between pharmacotherapy groups, individuals who switched medications were less likely to achieve abstinence at the end of treatment as compared to those whose medication treatment plans remained the same or who received adjunctive treatment (unchanged = 36.8%, adjunctive = 38.1% vs. switched = 20.9%, χ² = 9.59, df = 2, p = .008). In multivariate regression analysis, switching pharmacotherapy was associated with lower smoking cessation (OR = .33, 95% CI [.17, .63]) and significantly mediated the effectiveness of pharmacotherapy. As there were differences in medication switching rates at the clinical level, there were limitations in assessing the impact of mental illness or substance use disorder variables.

CONCLUSIONS

At least 40% of individuals may have their smoking cessation pharmacotherapy plan changed during treatment. Switching pharmacotherapy may indicate a subgroup of smokers characterized by greater challenges in smoking cessation. Our findings may enhance algorithms for using smoking cessation pharmacotherapy in clinical practice and provide directions for future research in treating tobacco use disorder among individuals with mental health and substance use disorders.

Smoking Behaviors and Medical Co-Morbidities in Patients With Mental Illnesses

Correlations among smoking behaviors and co-morbid medical illnesses were examined among 982 smokers with mental illnesses enrolled in a smoking cessation program within Mental Health and Addictions Services in Vancouver, Canada. Significant correlates among individuals with psychotic disorders included associations between a history of emphysema/chronic obstructive pulmonary (COPD) disease and cigarettes smoked per day (r's=.35, p≤.01), Confidence in quitting (r's=-.33, p≤.01), and nicotine dependence (r's=.32, p≤.01). Study findings may have implications for the development of integrated medical-psychiatric treatment delivery models that include comprehensive tobacco cessation programs tailored toward people with mental illnesses.

The safety of treatments for tobacco use disorder

INTRODUCTION

Tobacco continues to be a leading cause of preventable morbidity and mortality in the world. First-line pharmacotherapies for the treatment of tobacco use disorder include nicotine replacement therapy, bupropion sustained-release (SR), and varenicline. We provide an overview of current evidence on the safety of first-line pharmacotherapies for the treatment of tobacco use disorder.

AREAS COVERED

Randomized clinical trials published in English up to July 2015 were identified and reviewed through searches of PUBMED using the terms nicotine replacement therapy, bupropion SR, varenicline, smoking, and tobacco cessation.

EXPERT OPINION

Nicotine replacement has few contraindications and side effects and can be recommended to almost all tobacco users. Bupropion SR should be used with caution in patients with bipolar disorder or liver or kidney disease, and alternative treatments should be considered for patients with a history of seizures or who are at risk for seizures. The only contraindication for varenicline is an allergy to the medication, and nausea is the most common side effect. Varenicline can be used safely in patients with cardiovascular disease. Varenicline can be used in patients with stable psychiatric disease and safety can be ensured through close clinical monitoring.

Nicotine and the adolescent brain

Adolescence encompasses a sensitive developmental period of enhanced clinical vulnerability to nicotine, tobacco, and e-cigarettes. While there are sociocultural influences, data at preclinical and clinical levels indicate that this adolescent sensitivity has strong neurobiological underpinnings. Although definitions of adolescence vary, the hallmark of this period is a profound reorganization of brain regions necessary for mature cognitive and executive function, working memory, reward processing, emotional regulation, and motivated behavior. Regulating critical facets of brain maturation are nicotinic acetylcholine receptors (nAChRs). However, perturbations of cholinergic systems during this time with nicotine, via tobacco or e-cigarettes, have unique consequences on adolescent development. In this review, we highlight recent clinical and preclinical data examining the adolescent brain's distinct neurobiology and unique sensitivity to nicotine. First, we discuss what defines adolescence before reviewing normative structural and neurochemical alterations that persist until early adulthood, with an emphasis on dopaminergic systems. We review how acute exposure to nicotine impacts brain development and how drug responses differ from those seen in adults. Finally, we discuss the persistent alterations in neuronal signaling and cognitive function that result from chronic nicotine exposure, while highlighting a low dose, semi-chronic exposure paradigm that may better model adolescent tobacco use. We argue that nicotine exposure, increasingly occurring as a result of e-cigarette use, may induce epigenetic changes that sensitize the brain to other drugs and prime it for future substance abuse.

Emerging drugs for the treatment of tobacco dependence: 2014 update

INTRODUCTION

Tobacco dependence remains a global epidemic and the largest preventable cause of morbidity and mortality around the world. Smoking cessation has benefits at all ages but remains challenging for several reasons, among which are the complexities of nicotine addiction and limitations of available pharmacotherapies.

AREAS COVERED

This review summarizes current and emerging pharmacotherapies for the treatment of tobacco dependence, including first- and second-line recommended agents. Medications with alternative primary indications that have been investigated as potential treatments for tobacco dependence are also discussed. Articles reviewed were obtained through searches of PubMed, Ovid MEDLINE, ClinicalTrials.gov and the Pharmaprojects database.

EXPERT OPINION

Current evidence suggests that the two most effective pharmacotherapies to treat tobacco dependence are varenicline and combination nicotine replacement therapy. Alternative agents investigated demonstrate mixed rates of success in achieving long-term abstinence from smoking. No single pharmacotherapy will serve as a universally successful treatment given the complex underpinnings of tobacco dependence and individuality of smokers. The ultimate goal of tobacco research with respect to pharmacotherapeutic development continues to be providing clinicians with an armamentarium of drugs to choose from allowing for tailoring of treatment for smokers.

Hypnotherapy is more effective than nicotine replacement therapy for smoking cessation: results of a randomized controlled trial

BACKGROUND

The efficacy of pharmacotherapy for smoking cessation is well documented. However, due to relapse rates and side effects, hypnotherapy is gaining attention as an alternative treatment option. The aim of this one-center randomized study was to compare the efficacy of hypnotherapy alone, as well as hypnotherapy with nicotine replacement therapy (NRT), to conventional NRT in patients hospitalized with a cardiac or pulmonary illness.

METHODS

We evaluated self-reported and biochemically verified 7-day prevalence smoking abstinence rates at 12 and 26 weeks post-hospitalization. Patients (n=164) were randomized into one of three counseling-based treatment groups: NRT for 30 days (NRT; n=41), a 90-min hypnotherapy session (H; n=39), and NRT with hypnotherapy (HNRT; n=37). Treatment groups were compared to a "self-quit" group of 35 patients who refused intervention.

RESULTS

Hypnotherapy patients were more likely than NRT patients to be nonsmokers at 12 weeks (43.9% vs. 28.2%; p=0.14) and 26 weeks after hospitalization (36.6% vs. 18.0%; p=0.06). Smoking abstinence rates in the HNRT group were similar to the H group. There was no difference in smoking abstinence rates at 26 weeks between "self quit" and participants in any of the treatment groups. In multivariable regression analysis adjusting for diagnosis and demographic characteristics, H and HNRT were over three times more likely than NRT participants to abstain at 26-weeks post-discharge (RR=3.6; p=0.03 and RR=3.2; p=0.04, respectively).

CONCLUSION

Hypnotherapy is more effective than NRT in improving smoking abstinence in patients hospitalized for a smoking-related illness, and could be an asset to post-discharge smoking cessation programs.

Smoking cessation outcomes and predictors among individuals with co-occurring substance use and/or psychiatric disorders

OBJECTIVE

Individuals with substance use and psychiatric disorders have a high prevalence of tobacco use disorders and are disproportionately affected by tobacco-related morbidity and mortality. However, it is unclear how having co-occurring disorders affects tobacco cessation. Our aim was to examine smoking cessation outcomes and relevant predictors of smoking cessation among smokers with substance use and/or psychiatric disorders.

METHODS

Data from medical records of 674 participants in a tobacco treatment program within mental health and addictions services in Vancouver, Canada, were analyzed. The 26-week treatment program included an 8-week structured behavioral counseling group, an 18-week support group, and 26 weeks of no-cost pharmacotherapy. Information on demographics, tobacco use and history, type of pharmacotherapy received, nicotine dependence, importance of and confidence in quitting smoking, expired carbon monoxide level, substance use and psychiatric disorder history, and total program visits were gathered.

RESULTS

Approximately 67% (n = 449) of participants had co-occurring substance use and psychiatric disorders, while 20% (n = 136) had substance use disorder only, 10% (n = 67) had psychiatric disorder only, and 3% (n = 22) had tobacco dependence only. Rates of tobacco cessation (i.e., 7-day point prevalence of abstinence verified by expired carbon monoxide of ≤8 ppm) by group in the 522 people who completed treatment were as follows: 38.2% for those with co-occurring disorders, 47.1% for those with tobacco dependence only, 47.1% for those with substance use disorder only, and 41.8% for those with psychiatric disorder only. Length of treatment was a significant predictor of smoking cessation for those with co-occurring disorders and substance use disorder only. In the final stratified multivariate analysis, for individuals with co-occurring disorders, having an opiate use disorder (as compared to an alcohol use disorder) and higher nicotine dependence scores at baseline were predictive of poor cessation outcomes, while greater length of treatment was predictive of successful smoking cessation.

CONCLUSIONS

Tobacco cessation treatment for individuals with co-occurring substance use and psychiatric disorders is likely to be as effective as for smokers with either disorder alone. Treatment duration predicts success among these smokers so strategies to enhance engagement and retention are needed.

A preliminary study suggests that nicotine and prefrontal dopamine affect cortico-striatal areas in smokers with performance feedback

Nicotine and tonic dopamine (DA) levels [as inferred by catechol-O-methyl tranferase (COMT) Val158Met genotype] interact to affect prefrontal processing. Prefrontal cortical areas are involved in response to performance feedback, which is impaired in smokers. We investigated whether there is a nicotine × COMT genotype interaction in brain circuitry during performance feedback of a reward task. We scanned 23 healthy smokers (10 Val/Val homozygotes, 13 Met allele carriers) during two fMRI sessions while subjects were wearing a nicotine or placebo patch. A significant nicotine × COMT genotype interaction for BOLD signal during performance feedback in cortico-striatal areas was seen. Activation in these areas during the nicotine patch condition was greater in Val/Val homozygotes and reduced in Met allele carriers. During negative performance feedback, the change in activation in error detection areas such as anterior cingulate cortex (ACC)/superior frontal gyrus on nicotine compared to placebo was greater in Val/Val homozygotes compared to Met allele carriers. With transdermal nicotine administration, Val/Val homozygotes showed greater activation with performance feedback in the dorsal striatum, area associated with habitual responding. In response to negative feedback, Val/Val homozygotes had greater activation in error detection areas, including the ACC, suggesting increased sensitivity to loss with nicotine exposure. Although these results are preliminary due to small sample size, they suggest a possible neurobiological mechanism underlying the clinical observation that Val/Val homozygotes, presumably with elevated COMT activity compared to Met allele carriers and therefore reduced prefrontal DA levels, have poorer outcomes with nicotine replacement therapy.

A combination of buprenorphine and naltrexone blocks compulsive cocaine intake in rodents without producing dependence

Buprenorphine, a synthetic opioid that acts at both μ and κ opioid receptors, can decrease cocaine use in individuals with opioid addiction. However, the potent agonist action of buprenorphine at μ opioid receptors raises its potential for creating opioid dependence in non-opioid-dependent cocaine abusers. Here, we tested the hypothesis that a combination of buprenorphine and naltrexone (a potent μ opioid antagonist with weaker δ and κ antagonist properties) could block compulsive cocaine self-administration without producing opioid dependence. The effects of buprenorphine and various doses of naltrexone on cocaine self-administration were assessed in rats that self-administered cocaine under conditions of either short access (noncompulsive cocaine seeking) or extended access (compulsive cocaine seeking). Buprenorphine alone reproducibly decreased cocaine self-administration. Although this buprenorphine-alone effect was blocked in a dose-dependent manner by naltrexone in both the short-access and the extended-access groups, the combination of the lowest dose of naltrexone with buprenorphine blocked cocaine self-administration in the extended-access group but not in the short-access group. Rats given this low dose of naltrexone with buprenorphine did not exhibit the physical opioid withdrawal syndrome seen in rats treated with buprenorphine alone, and naltrexone at this dose did not block κ agonist-induced analgesia. The results suggest that the combination of buprenorphine and naltrexone at an appropriate dosage decreases compulsive cocaine self-administration with minimal liability to produce opioid dependence and may be useful as a treatment for cocaine addiction.

Sex differences in nicotine dependence among addictions clients accessing a smoking cessation programme in Vancouver, British Columbia, Canada

Most individuals in drug treatment programmes use tobacco and are dependent on nicotine. For 323 participants (65% men, mean age = 49.3 years) with a history of substance use disorder (SUD) and/or psychiatric disorders (PD) enrolled in a tobacco dependence clinic programme, we compared baseline characteristics among women and men and examined factors associated with nicotine dependence (ND). Individuals with mood, anxiety and psychotic disorders were more likely to be female, whereas men were more likely to be characterized by alcohol, cocaine and marijuana use, older age, older age at smoking initiation and higher confidence in quitting smoking scores. In stratified multivariate analyses, among women, history of an anxiety disorder and a greater number of cigarettes smoked per day were associated with higher ND scores; among men, a greater number of cigarettes smoked per day and higher confidence in quitting scores were associated with higher ND scores. Given the differences in smoking, SUD and PD histories between women and men accessing addiction treatment, and differential associations with ND, it is important to further explore factors that may enhance tailored treatments and inform future studies examining biological and psychosocial factors for tobacco use in SUD and PD treatment populations.

Pretreatment lifestyle behaviors as survival predictors for patients with nasopharyngeal carcinoma

BACKGROUND

Lifestyle behaviors have been widely reported to influence the survival of patients with head and neck cancer. However, the relationship between pretreatment lifestyle behaviors and survival among patients with nasopharyngeal carcinoma (NPC) is unclear.

METHODS

A prospective cohort study was designed to determine the relationship between lifestyle behaviors and survival in 1,533 NPC patients recruited from October 2005 to October 2007. Pretreatment lifestyle behaviors (such as body-mass index [BMI], smoking, alcohol, diet) of the patients were investigated. Univariate and multivariate proportional-hazards models were used to assess the impact of lifestyle behaviors on patient survival.

RESULTS

Smoking was a predictor of survival; both current smokers (hazard ratio [HR] = 1.88; 95% CI, 1.33 to 2.65) and heavy smokers (≥ 25 Pack-years; HR = 1.84; 95% CI, 1.30 to 2.60) showed associations with poor survival. Higher BMI was significantly associated with a lower risk of death (P(trend) = 0.002). Compared with under/normal-weight patients (BMI less than 22.99 kg/m(2)), the multivariate HR for survival was 0.66 (95% CI, 0.48 to 0.90) and 0.47 (95% CI, 0.23 to 0.97) for overweight and obese patients, respectively. No alcohol intake and high fruit intake were associated with favorable survival in the univariate analysis but lost significance in the multivariate model.

CONCLUSION

Our findings indicate that pretreatment lifestyle behaviors, especially smoking status and BMI, as easily available data, provide prognostic value for survival in NPC patients.

Smoking Cessation Among Persons With Co-Occurring Substance Use Disorder and Mental Illness

Aims:A history of either a substance use disorder (SUD) or psychiatric disorder (PD) is associated with tobacco use. However, there is limited information available on tobacco dependence treatment outcomes among individuals with co-occurring SUD and PD.Methods:Data from 202 participants enrolled in a tobacco dependence treatment program in an outpatient clinic setting were analysed.Findings:In multivariate analysis, having a history of SUD only (OR =.11, 95% CI = .02–.76) and having a co-occurring SUD and PD (OR = .13, 95% CI = .02–.81), as compared to having neither, were significant predictors of a lower likelihood of achieving smoking abstinence.Conclusions:A history of SUD and PD is an important predictor of poor smoking cessation outcomes; however, using more intensive, tailored approaches to tobacco dependence treatment appears to be promising. Future studies may need to further address the nature of tobacco dependence treatment in settings were PDs and other SUDs are managed in order to achieve optimal outcomes.

Sex differences in smoking cessation outcomes of a tailored program for individuals with substance use disorders and mental illness

Tobacco use is highly prevalent among individuals with a history of substance use disorders (SUD) and/or mental illness (MI). Despite evidence of differences in smoking cessation (SC) outcomes between women and men, few studies have formally evaluated sex differences among SUD and/or MI populations. For 258 participants (62% male, mean age=48.6 years) with an SUD and/or MI enrolled in a tobacco dependence clinic (TDC) program, we examined SC outcomes and compared men's and women's predictors of end-of-treatment abstinence. Individuals with an MI, social support for quitting, and a greater number of visits to the TDC program were more likely to be female; whereas males were characterized by having an SUD, older age, smoking a greater number of cigarettes per day, and having higher confidence in quitting smoking. In the intent-to-treat analysis, end-of-treatment smoking cessation was 32.2% (females=35.4% vs males=30.2, χ(2)=0.74, df=1, p=.390). Among females, baseline expired carbon monoxide (CO) level and a greater number of visits to the program were significantly predictive of SC; among males, having a history of alcohol, heroin and other opioids, and marijuana use were predictive of unsuccessful SC, whereas baseline expired CO level and a greater number of visits to the program were predictive of SC. These factors may be important in the design of enhanced tailored treatments and development of future SC programs for individuals with SUD and MI.

Zebrafish for the study of the biological effects of nicotine

INTRODUCTION

Zebrafish are emerging as a powerful animal model for studying the molecular and physiological effects of nicotine exposure. The zebrafish have many advantageous physical characteristics, including small size, high fecundity rates, and externally developing transparent embryos. When combined with a battery of molecular-genetic tools and behavioral assays, these attributes enable studies to be conducted that are not practical using traditional animal models.

METHODS

We reviewed the literature on the application of the zebrafish model as a preclinical model to study the biological effects of nicotine exposure.

RESULTS

The identified studies used zebrafish to examine the effects of nicotine exposure on early development, addiction, anxiety, and learning. The methods used included green fluorescent protein-labeled proteins to track in vivo nicotine-altered neuron development, nicotine-conditioned place preference, and locomotive sensitization linked with high-throughput molecular and genetic screens and behavioral models of learning and stress response to nicotine. Data are presented on the complete homology of all known human neural nicotinic acetylcholine receptors in zebrafish and on the biological similarity of human and zebrafish dopaminergic signaling.

CONCLUSIONS

Tobacco dependence remains a major health problem worldwide. Further understanding of the molecular effects of nicotine exposure and genetic contributions to dependence may lead to improvement in patient treatment strategies. While there are limitations to the use of zebrafish as a preclinical model, it should provide a valuable tool to complement existing model systems. The reviewed studies demonstrate the enormous opportunity zebrafish have to advance the science of nicotine and tobacco research.

The tobacco-dependence clinic: intensive tobacco-dependence treatment in an addiction services outpatient setting

We present outcomes from an intensive tobacco-dependence treatment program for addiction services clients at three different sites. Data from 202 participants were analyzed. For individuals who completed the program, the abstinence rate was 43%. Not having a primary substance use history and a lower carbon monoxide (CO) level at intake predicted abstinence; whereas being female, the particular site of intervention, receiving both nicotine replacement therapy (NRT) and oral medication, and having a lower CO level at baseline predicted program completion. Drug treatment clients can successfully quit smoking at rates similar to the general population when given access to intensive tobacco-dependence treatment. 

Clinical utility of varenicline for smokers with medical and psychiatric comorbidity

Chronic obstructive pulmonary disease (COPD) is a costly and deadly disease afflicting an estimated 210 million people and accounting for 5% of all global deaths. Exposure to cigarette smoke is the greatest risk factor for COPD in the developed world. Smoking cessation improves respiratory symptoms and lung function and reduces mortality among patients with COPD. Cigarette smokers with COPD and other co-morbid conditions such as cardiovascular disease and psychiatric illnesses should receive comprehensive tobacco treatment interventions incorporating efficacious pharmacotherapies. Varenicline, an α₄β₂ nicotinic acetylcholine receptor partial agonist, is the newest and most effective drug currently available to promote smoking cessation. In conjunction with behavioral interventions and clinical monitoring for potential side effects, varenicline offers great hope for reducing smoking-attributable death and disability.

Smoking cessation pharmacotherapy

Cigarette smoking remains an important risk factor for premature cardiovascular disease and its many complications. There are clear benefits from treating tobacco dependence on the rate of clinical outcomes. In addition to behavioral therapies, various pharmacologic strategies have been developed to help achieve this goal. First-line therapies include nicotine replacement, bupropion and varenicline, a partial nicotine antagonist. Second-line treatments include clonidine and nortriptyline. Additional treatment strategies with less proven efficacy include monoamine oxidase inhibitors, selective serotonin reuptake inhibitors, opioid receptor antagonists, bromocriptine, anti-anxiety drugs, nicotinic receptor antagonists (e.g. mecamylamine) and glucose tablets. Various approaches under investigation include inhibitors of the hepatic P450 enzyme (e.g. methoxsalen), cannabinoid-1 receptor antagonists (e.g. rimonabant), and nicotine vaccines.

Emerging drugs for the treatment of tobacco dependence

BACKGROUND

Tobacco use is a worldwide epidemic expected to cause 10 million annual deaths by 2020 globally. Newer pharmacotherapy increases the specificity of tobacco dependence treatment by affecting receptors mediating nicotine effects.

OBJECTIVE

To review current and emerging pharmacotherapy for the treatment of tobacco use.

METHODS

Articles retrieved with searches conducted through PubMed, Pharmaprojects database, Datamonitor, the Internet, and the author's personal files.

RESULTS/CONCLUSIONS

Traditional drug therapy for tobacco dependence has treated tobacco dependence by replacing nicotine or mediating nicotine withdrawal and craving through neurotransmitter modulation. Varenicline, an alpha4beta2 nAChR partial agonist, is an emerging drug therapy that modifies tobacco use behavior by acting directly on nicotine receptors in the reward centers of the central nervous system. Available data suggests that varenicline is the most effective pharmacotherapy currently available. Drug development in the area of tobacco dependence is desperately needed in order to further decrease the death and disability associated with tobacco use.