Nicotine replacement therapy

Behavioural support and nicotine replacement therapy for smokeless tobacco cessation in Bangladesh, India and Pakistan: A pilot randomized controlled trial

BACKGROUND AND AIMS

Smokeless tobacco (ST) use in South Asia is high, yet interventions to support its cessation are lacking. We tested the feasibility of delivering interventions for ST cessation in South Asia.

DESIGN

We used a 2 × 2 factorial design, pilot randomized controlled trial with a duration of 26 weeks, including baseline and follow-up (6, 12 and 26 weeks) assessments.

SETTING

Two primary health-care facilities each in Dhaka (Bangladesh) and Karachi (Pakistan) and a walk-in cancer screening clinic in Noida (India) took part.

PARTICIPANTS

Adult daily ST users willing to make a quit attempt within 30 days. Of 392 screened, 264 participants [mean age: 35 years, standard deviation = 12.5, 140 (53%) male] were recruited between December 2020 and December 2021; 132 from Bangladesh, 44 from India and 88 from Pakistan.

INTERVENTIONS

Participants were randomized to one of three treatment options [8-week support through nicotine replacement therapy (NRT, n = 66), a behavioural intervention for smokeless tobacco cessation in adults (BISCA, n = 66) or their combination (n = 66)] or the control condition of very brief advice (VBA) to quit (n = 66).

MEASUREMENTS

Recruitment and retention, data completeness and feasibility of intervention delivery were evaluated. Biochemically verified abstinence from tobacco, using salivary cotinine, was measured at 26 weeks.

FINDINGS

Retention rates were 94.7% at 6 weeks, dropping to 89.4% at 26 weeks. Attendance in BISCA pre-quit (100%) and quit sessions (86.3%) was high, but lower in post-quit sessions (65.9%), with variability among countries. Adherence to NRT also varied (45.5% Bangladesh, 90% India). Data completion for key variables exceeded 93% among time-points, except at 26 weeks for questions on nicotine dependence (90%), urges (89%) and saliva samples (62.7%). Among follow-up time-points, self-reported abstinence was generally higher among participants receiving BISCA and/or NRT. At 26 weeks, biochemically verified abstinence was observed among 16 (12.1%) participants receiving BISCA and 13 (9.8%) participants receiving NRT.

CONCLUSIONS

This multi-country pilot randomized controlled trial of tobacco cessation among adult smokeless tobacco users in South Asia demonstrated the ability to recruit and retain participants and report abstinence, suggesting that a future definitive smokeless tobacco cessation trial is viable.

Extraction and Purification of Nicotine from Tobacco Rhizomes by Supercritical CO2

Currently, in the ongoing development of the tobacco industry, a large amount of tobacco rhizomes is discarded as waste. These wastes are usually disposed of through incineration or burial. However, these tobacco wastes still have some economic value. High-purity nicotine has a promising market outlook as the primary raw material for electronic cigarette liquid. Nicotine is not only found in tobacco leaves but also in the rhizomes of tobacco plants. This study presents a method for treating tobacco waste and extracting high-purity nicotine from it. After mixing the raw material powder and entrainer in specific ratios, as much of the nicotine in tobacco roots can be extracted as possible using supercritical carbon dioxide extraction. The effects of temperature, the ratio of the entrainer, and the volume fraction of ethanol in the entrainer on the nicotine yield in supercritical fluid extraction (SFE) at 25 MPa for 120 min were discussed. By using 90% ethanol (a raw material mass-to-volume ratio of 1:5) as the entrainer, we obtained the highest nicotine yield of 0.49% at 65 °C. Meanwhile, the purity of the crude extract was 61.71%, and after purification, it increased to 97.57%. In this way, we can not only obtain nicotine with market value but also further reduce the harm to the environment caused by tobacco waste disposal.

Behavioural support and nicotine replacement therapy for smokeless tobacco cessation: protocol for a pilot randomised-controlled multi-country trial

BACKGROUND

Smokeless tobacco (ST) is consumed globally by more than 350 million people, with approximately 85% of all users based in South and Southeast Asia. In this region, ST products are cheap and easily accessible. Evidence-based interventions to people quit ST use are lacking. This study aims to test the feasibility of conducting a future definitive trial of ST cessation, using a culturally adapted behavioural intervention, and/or nicotine replacement therapy (NRT) in three South Asian countries.

METHODS

We will conduct a factorial design, randomised-controlled pilot trial in Bangladesh, India and Pakistan. Daily ST users will be recruited from primary health care settings in Dhaka, Noida and Karachi. Participants will be individually randomised to receive intervention A (4 or 6 mg NRT chewing gum for 8-weeks), intervention B (BISCA: face-to-face behavioural support for ST cessation), a combination of interventions A and B or usual care (Very Brief Advice - VBA). The participants will provide demographic and ST use related data at baseline, and at 6, 12 and 26 weeks of follow-up. Salivary cotinine samples will be collected at baseline and 26 weeks. The analyses will undertake an assessment of the feasibility of recruitment, randomisation, data collection and participant retention, as well as the feasibility of intervention delivery. We will also identify potential cessation outcomes to inform the main trial, understand the implementation, context and mechanisms of impact through a process evaluation and, thirdly, establish health resource use and impact on the quality of life through health economic data.

DISCUSSION

The widespread and continued use of ST products in South Asia is consistent with a high rate of associated diseases and negative impact on the quality of life. The identification of feasible, effective and cost-effective interventions for ST is necessary to inform national and regional efforts to reduce ST use at the population level. The findings of this pilot trial will inform the development of larger trials for ST cessation among South Asian users, with relevance to wider regions and populations having high rates of ST use.

TRIAL REGISTRATION

ISRCTN identifier 65109397.

A Time-to-Event Model Relating Integrated Craving to Risk of Smoking Relapse Across Different Nicotine Replacement Therapy Formulations

Smoking increases the risk of cancer and other diseases, causing an estimated 7 million deaths per year. Nicotine replacement therapy (NRT) reduces craving for smoking, therefore, increasing an individual's probability to remain abstinent. In this work, we for the first time quantitatively described the relationship between craving and smoking abstinence, using retrospectively collected data from 19 studies, including 3 NRT formulations (inhaler, mouth spray, and patch) and a combination of inhaler and patch. Smokers motivated to quit were included in the NRT or placebo arms. Integrated craving (i.e., craving over a period of time) was assessed with 4-category, 5-category, or 100-mm visual analogue scale. The bounded integer model was used to assess latent craving from all scales. A time-to-event model linked predicted integrated craving to the hazard of smoking relapse. Available data included 9,323 adult subjects, observed for 3 weeks up to 2 years. At the study end, 9% (11% for NRT and 5% for placebo), on average, remained abstinent according to the protocol definition. A Gompertz-Makeham hazard best described the data, with a hazard of smoking relapse decreasing over time. Latent integrated craving was positively related to the hazard of smoking relapse, through a sigmoidal maximum effect function. For the same craving, being on NRT was found to reduce the hazard of relapse by an additional 30% compared with placebo. This work confirmed that low craving is associated with a high probability of remaining smoking abstinent and that NRT, in addition to reducing craving, increases the probability of remaining smoking abstinent.

Relating Nicotine Plasma Concentration to Momentary Craving Across Four Nicotine Replacement Therapy Formulations

Tobacco use is a major health concern. To assist smoking cessation, nicotine replacement therapy (NRT) is used to reduce nicotine craving. We quantitatively described the relationship between nicotine pharmacokinetics (PKs) from NRTs and momentary craving, linking two different pharmacodynamic (PD) scales for measuring craving. The dataset comprised retrospective data from 17 clinical studies and included 1,077 adult smokers with 39,802 craving observations from four formulations: lozenge, gum, mouth spray, and patch. A PK/PD model was developed that linked individual predicted nicotine concentrations with the categorical and visual analogue PD scales through a joint bounded integer model. A maximum effect model, accounting for acute tolerance development, successfully related nicotine concentrations to momentary craving. Results showed that all formulations were similarly effective in reducing craving, albeit with a fourfold lower potency for the patch. Women were found to have a higher maximal effect of nicotine to reduce craving, compared with men.

Correlates of the Use of Different Tobacco Cessation Methods by Smokers and Smokeless Tobacco Users According to Their Socio-Demographic Characteristics: Global Adult Tobacco Survey (GATS) India 2009-10

BACKGROUND

Tobacco control has two aspects. One involves preventing non-tobacco users from using tobacco and the second involves tobacco cessation (quitting) by existing tobacco users. There are various methods of tobacco cessation. Pharmacotherapy [e.g., nicotine replacement therapy (NRT) and medications such as bupropion] and behavioral counselling are some of the internationally approved methods of tobacco cessation.

OBJECTIVE

This paper intends to study how age, gender, residence (rural/urban), education, and occupation influence the use of various tobacco cessation methods by smokers and smokeless tobacco users.

MATERIALS AND METHODS

The study was a cross-sectional secondary data analysis of the Global Adult Tobacco Survey (GATS) India 2009-2010. There were 3725 smokers and 6354 smokeless tobacco users included in the study who made attempts to quit in the 12 months prior to the survey by use of different cessation methods (NRT, drugs such as bupropion, counselling, and other methods).

RESULTS

A significant association was demonstrated between increasing educational attainment and use of cessation methods for all the methods among smokers. Being employed (Govt. or non-Govt.) was positively associated with the use of NRT as a cessation method by smokers. Students and homemakers had higher odds of using pharmacotherapy methods among smokers. A significant association was demonstrated for the gender and age of tobacco users with the use of counselling as a cessation method among smokeless tobacco users.

CONCLUSION

The findings of this study have important implications for tobacco cessation service providers in view of supporting their decision of choosing a particular tobacco cessation method for tobacco users according to certain kinds of sociodemographic characteristics.

Neurobiological Bases of Cue- and Nicotine-induced Reinstatement of Nicotine Seeking: Implications for the Development of Smoking Cessation Medications

A better understanding of the neurobiological factors that contribute to relapse to smoking is needed for the development of efficacious smoking cessation medications. Reinstatement procedures allow the preclinical assessment of several factors that contribute to relapse in humans, including re-exposure to nicotine via tobacco smoking and the presentation of stimuli that were previously associated with nicotine administration (i.e., conditioned stimuli). This review provides an integrated discussion of the results of animal studies that used reinstatement procedures to assess the efficacy of pharmacologically targeting various neurotransmitter systems in attenuating the cue- and nicotine-induced reinstatement of nicotine seeking. The results of these animal studies have increased our understanding of the neurobiological processes that mediate the conditioned effects of stimuli that trigger reinstatement to nicotine seeking. Thus, these findings provide important insights into the neurobiological substrates that modulate relapse to tobacco smoking in humans and the ongoing search for novel efficacious smoking cessation medications.

Involvement of neuronal β2 subunit-containing nicotinic acetylcholine receptors in nicotine reward and withdrawal: implications for pharmacotherapies

WHAT IS KNOWN AND OBJECTIVE

Tobacco smoking remains a major health problem. Nicotine binds to nicotinic acetylcholine receptors (nAChRs), which can cause addiction and withdrawal symptoms upon cessation of nicotine administration. Pharmacotherapies for nicotine addiction target brain alterations that underlie withdrawal symptoms. This review will delineate the involvement of the β2 subunit of neuronal nAChRs in nicotine reward and in generating withdrawal symptoms to better understand the efficacy of smoking cessation pharmacotherapies.

COMMENT

Chronic nicotine desensitizes and upregulates β2 subunit-containing nAChRs, and the prolonged upregulation of receptors may underlie symptoms of withdrawal. Experimental research has demonstrated that the β2 subunit of neuronal nAChRs is necessary for generating nicotine reward and withdrawal symptoms.

WHAT IS NEW AND CONCLUSION

Smoking cessation pharmacotherapies act on β2 subunit-containing nAChRs to reduce nicotine reward and withdrawal symptom severity.

A computational hypothesis for allostasis: delineation of substance dependence, conventional therapies, and alternative treatments

The allostatic theory of drug abuse describes the brain's reward system alterations as substance misuse progresses. Neural adaptations arising from the reward system itself and from the antireward system provide the subject with functional stability, while affecting the person's mood. We propose a computational hypothesis describing how a virtual subject's drug consumption, cognitive substrate, and mood interface with reward and antireward systems. Reward system adaptations are assumed interrelated with the ongoing neural activity defining behavior toward drug intake, including activity in the nucleus accumbens, ventral tegmental area, and prefrontal cortex (PFC). Antireward system adaptations are assumed to mutually connect with higher-order cognitive processes occurring within PFC, orbitofrontal cortex, and anterior cingulate cortex. The subject's mood estimation is a provisional function of reward components. The presented knowledge repository model incorporates pharmacokinetic, pharmacodynamic, neuropsychological, cognitive, and behavioral components. Patterns of tobacco smoking exemplify the framework's predictive properties: escalation of cigarette consumption, conventional treatments similar to nicotine patches, and alternative medical practices comparable to meditation. The primary outcomes include an estimate of the virtual subject's mood and the daily account of drug intakes. The main limitation of this study resides in the 21 time-dependent processes which partially describe the complex phenomena of drug addiction and involve a large number of parameters which may underconstrain the framework. Our model predicts that reward system adaptations account for mood stabilization, whereas antireward system adaptations delineate mood improvement and reduction in drug consumption. This investigation provides formal arguments encouraging current rehabilitation therapies to include meditation-like practices along with pharmaceutical drugs and behavioral counseling.

Evaluation of Rhodiola rosea L. extract on affective and physical signs of nicotine withdrawal in mice

The aim of the present study was to investigate the effects of a Rhodiola rosea L. extract on the prevention of the development of nicotine dependence and for the reduction of abstinence suffering following nicotine cessation in mice. Dependence was induced in mice by subcutaneous injections of nicotine (2 mg/kg, 4 times/day) for eight days. Spontaneous abstinence syndrome was evaluated 20 h after the last nicotine administration, by analysis of withdrawal signs, as affective (anxiety-like behaviour) and physical (somatic signs and locomotor activity). Rhodiola rosea L. extract was administered orally during nicotine treatment (10, 15 and 20 mg/kg) or during nicotine withdrawal (20 mg/kg). Results show that both affective and somatic signs (head shaking, paw tremors, body tremors, ptosis, jumping, piloerection and chewing) induced by nicotine withdrawal are abolished by administration of Rhodiola rosea L. extract in a dose-dependent fashion, during both nicotine exposure and nicotine cessation. In conclusion, our data encourage additional studies to define the use of R. rosea L. as a therapeutic approach in the treatment of smoking cessation.

Management of cardiovascular disease in renal transplant recipients

Cardiovascular disease is a major cause of graft loss and the leading cause of death in renal transplant recipients. Although there are robust data on the frequency of risk factors and their contributions to cardiovascular disease in this population, few trials have demonstrated the benefit of modifying these risk factors to reduce cardiovascular events. Nevertheless, it is widely accepted that the clinical acumen filtered through the best available studies in the general population be used to treat individual renal transplant recipients given their high cardiovascular mortality. Transplant task forces and the Kidney Disease Outcomes Quality Initiative have created guidelines for this purpose. This review examines the data available for prevention and treatment of major risk factors contributing to cardiovascular disease in renal transplant recipients. The contribution of immunosuppressive agents to each risk factor and the evidence to support lifestyle modification as well as drug therapy are examined. Reducing cardiovascular risk factors requires an integrative approach that is best accomplished by a team of health care professionals. It creates a significant challenge but one that must be met if allograft survival is to improve.

Comparison of Nicotine Pharmacokinetics in Healthy Japanese Male Smokers Following Application of the Transdermal Nicotine Patch and Cigarette Smoking

Transdermal nicotine patch (TNP) contains approximately 16.6 and 24.9 mg of nicotine per 20 and 30 cm2 (TNP-20 and TNP-30). The aims of the study are to investigate linearity of nicotine pharmacokinetics after single application of different strengths of TNP and to directly compare plasma nicotine concentrations with those during cigarette smoking. Twelve healthy Japanese male smokers were randomly allocated to 1 of 2 cohorts consisting of 6 subjects each. Cohort 1 subjects received 1 sheet of TNP-20 (TNP-20x1) in period 1, and 2 sheets of TNP-20 (TNP-20x2) in period 3. Cohort 2 subjects were received 1 sheet of TNP-30 (TNP-30x1) in period 2, and smoked a total of 12 cigarettes at 1 h intervals in period 4. Each TNP was applied to the upper arm for 16 h. After TNP-20x1 or TNP-20x2 treatment in cohort 1, the amount of nicotine delivered from TNP (Dose) was proportional to surface area of TNP. Cmax and AUC of nicotine increased with the surface area (Dose), and tmax, t(1/2), CL/F and percentage of dose excreted in urine were almost the same between both treatments. These suggest the linear pharmacokinetics of nicotine in proportion to the surface area and Dose following single application of TNP in identical subjects. In cohort 2, the plasma nicotine concentrations after TNP-30x1 treatment were approximately half those just before each smoking.

Investigations using immunization to attenuate the psychoactive effects of nicotine

Despite the enormous health risks, people continue to smoke and use tobacco primarily as a result of nicotine addiction. As part of our immunopharmacotherapy research, the effects of active and passive immunizations on acute nicotine-induced locomotor activity in rats were investigated. To this end, rats were immunized with either a NIC-KLH immunoconjugate vaccine designed to elicit an antinicotine immune response, or were administered an antinicotine monoclonal antibody, NIC9D9, prior to a series of nicotine challenges and testing sessions. Vaccinated rats showed a 45% decrease in locomotor activity compared to a 16% decrease in controls. Passive immunization with NIC9D9 resulted in a 66.9% decrease in locomotor activity versus a 3.4% decrease in controls. Consistent with the behavioral data, much less nicotine was found in the brains of immunized rats. The results support the potential clinical value of immunopharmacotherapy for nicotine addiction in the context of tobacco cessation programs.

A two-dimensional imaging biosensor to monitor enhanced brain glutamate release stimulated by nicotine

In this study, we have imaged and monitored real-time release of neurotransmitter glutamate from mouse brain slices stimulated by nicotine and physiological salts using a newly developed two-dimensional (2D) imaging biosensor. Nicotine, the addictive substance contained in cigarettes and other tobacco baring products, affects human body through interactions with both central and peripheral nervous system receptors and exists in various concentrations in body organs including the brain. The 2D imaging biosensor, designed for sensitive glutamate monitoring, is prepared through the use of a flat silica plate that is covalently attached with an enzyme, glutamate dehydrogenase (GDH). The 2D imaging biosensor can spatially resolve glutamate release and has a detection limit of 40 nM in detecting glutamate release from glutaminergic neurons in the brain slices. Using this biosensor, we have shown that the administration of nicotine (50 nM) on the brain slice stimulates repetitive glutamate release. To the best of our knowledge, this is the first time that a biosensor was used to define the vital role of nicotine in glutamate release. Physiological salts such as KCl and CaCl(2) have also been used to characterize the biosensor in measuring glutamate release. It is found in this study that nicotine stimulation is much more potent than physiological salts. The real-time detection of newly released glutamate from mouse brain slices clearly demonstrates the feasibility of the two-dimensional glutamate biosensor for real-time monitoring of dynamic glutamate release from living specimen.

Pharmacologic treatment of chronic obstructive pulmonary disease: past, present, and future

Pharmacologic treatment of chronic obstructive pulmonary disease (COPD) has evolved considerably during the past several decades. Initial treatment of the disease was accomplished primarily through antibiotics, mucolytic agents, and nonselective sympathomimetic agents. Up-to-date treatment guidelines stratified according to strength of evidence are published in the National Heart, Lung, and Blood Institute-World Health Organization workshop report on the Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease. Current drug therapy for stable COPD focuses primarily on bronchodilation through inhaled beta2-agonists and anticholinergic agents, immunization, and elimination of smoking as a risk factor. Although many pharmacologic agents are available to treat COPD, no drug has demonstrated effectiveness in halting progression of the disease. Rather, the goal of drug therapy at this time is to maintain control of symptoms and prevent COPD exacerbations. Compared with asthma, research into treatment for COPD has been minimal. However, a long-acting anticholinergic agent, tiotropium, has received approval status by the United States Food and Drug Administration. The drug has been shown to improve spirometric parameters, quality of life, and utilization of health care resources. In addition, several new targets for the treatment of COPD are being studied, and a few agents, including some that theoretically may slow functional decline in patients with COPD, are in development.

Rehabilitation unit staff attitudes toward substance abuse: changes and similarities between 1985 and 20011,21No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or any organization with which the authors are associated.2Reprints are not available

OBJECTIVES

(1) To assess the attitudes of the members of an inpatient rehabilitation unit team toward their unit's substance abuse and tobacco use policies, and (2) to compare the findings with those of a survey 16 years earlier.

DESIGN

An anonymous repeated assessment of staff attitudes and behaviors.

SETTING

A 47-bed inpatient rehabilitation unit.

PARTICIPANTS

Rehabilitation unit nurses, occupational and physical therapists, psychologists, physicians, social workers, and speech pathologists.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Change in response with time.

RESULTS

Seventy percent (89/128) of the staff members completed the survey. Seventy-two percent believed that they were "familiar or very familiar" with the unit's substance abuse policy and 51% were "concerned" or "very concerned" about their patients' alcohol and drug use. Nineteen percent reported complaints about the policy from their patients and 8% reported complaints from family members. Support for a uniform substance abuse policy remained high: 96% supported a uniform policy in both 1985 and 2001. However, only 15% believed that staff drug abuse education was adequate and only 45% believed that the current policy was "adequate" or "very adequate." (Corresponding responses in 1985 were 20% and 50%, respectively.) All but 1 respondent considered tobacco use an addiction, but only 48% believed that their patients were routinely assessed for its use.

CONCLUSION

Support for a uniform substance abuse policy remains strong. Although most team members support the policy, they believe that their education about substance abuse is inadequate. Staff members almost unanimously accept tobacco use as an addiction, but they believe that assessment and intervention efforts are poor.

Correlation and predictive performances of saliva and plasma nicotine concentration on tobacco withdrawal-induced craving

AIMS

To investigate whether saliva is a useful alternative to plasma for routine monitoring of nicotine and evaluate the predictive performances of saliva and plasma concentration on craving estimated by a Tiffany Questionnaire on Smoking Urge-Brief Form.

METHODS

Thirteen healthy smokers were enrolled in a randomized, two period, crossover trial. Linear and power models were evaluated to predict the plasma nicotine concentrations from the saliva measurements, whereas a population PK/PD indirect response model was used to predict craving using either saliva or plasma nicotine concentration as the independent variable.

RESULTS

The results of the analysis revealed that the power model was preferred over the linear one. The bias on the predicted plasma concentrations was of 0.47 ng ml-1 with a 95% confidence interval of [-0.57, 1.52] and a precision of 5.68 ng ml-1. The placebo effect model was initially fitted to data, then the indirect response approach (with inhibition in k(in)) was used to model the craving scores using plasma and saliva nicotine concentrations as independent variables. The two indirect response PK/PD models based on saliva and plasma nicotine concentrations, adequately described the onset, extent, and duration of craving. The maximal inhibition I(max) was 0.722 and 1 for saliva and plasma concentrations while the estimated nicotine concentrations giving 50% of the maximal inhibition were 269 ng ml-1 and 24.3 ng ml-1 for saliva and plasma, respectively.

CONCLUSIONS

A good correlation between plasma and saliva nicotine concentrations has been found using a power model. Comparable values of bias and precision on the model-predicted craving indicate that plasma and saliva concentration can equally well be used to predict the onset of tobacco withdrawal induced craving. Analysis of saliva definitely offers a potentially more attractive way to assess nicotine concentration values, as samples can be collected easily and noninvasively. In addition, saliva sampling avoids the pain and discomfort involved in venepuncture. In studies that assess psychological measures, such as subjective mood, blood collection could present a possible confounding factor because of the anxiety and pain that accompanies it. For these reasons saliva can reasonably be considered as the ideal sampling site for all clinical studies conducted for the evaluation of the potential activity of drugs on nicotine deprivation symptoms.

Stopping smoking: a prospective, randomized, double-blind study comparing nortriptyline to placebo

OBJECTIVE

The administration of antidepressant drugs was shown to positively affect the rate of smoking cessation. This study evaluates the efficacy of nortriptyline in an antismoking program.

METHODS

A possible randomized double-blind study that included 144 patients who were randomized to receive nortriptyline, 75 mg/d (68 patients), or placebo (76 patients), during 6 consecutive weeks. All patients attended behavioral group orientation for 5 weeks. The rate of success, complications, adherence to the regime, and factors of pretreatment prognosis were evaluated (multivariate analysis).

RESULTS

The groups were balanced in relation to the characteristics of the patients on entering the study. Patients receiving nortriptyline showed significantly higher cessation rate (55.9%) compared to the group receiving placebo (23.3%; p < 0.001). In a univariate analysis on prognosis factors influencing the rate of cessation in our study, the Fagerström test results (p = 0.005) and nortriptyline (p < 0.001) were identified. Logistic regression showed that a Fagerström test score of < 7 (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.47 to 6.7; p = 0.003) and nortriptyline use (OR, 4.1; 95% CI, 2 to 8.3; p < 0.001) were independent factors impacting the rate of success for smoking cessation. No significant complications were observed in the nortriptyline group.

CONCLUSION

This study showed that nortriptyline significantly increases the smoking cessation rate in chronic smokers, as compared to the placebo group, without any significant side effects.

Smoking cessation: a role for every practitioner

Despite the long-term efforts of governments and health professionals, smoking is still the single most important public health problem in the UK today. The addictiveness of nicotine means that very few unsupported attempts to quit are successful. This article provides an overview of the public health implications of smoking in the UK, the benefits of stopping smoking, and examines what community nurses can do to help and support people who want to quit.

Substance abuse attitudes and policies in US rehabilitation training programs: a comparison of 1985 and 2000

OBJECTIVE

To assess and compare the attitudes, beliefs, and policies of physical medicine and rehabilitation (PM&R) training programs toward substance abuse and tobacco use over the last 15 years.

DESIGN

A blinded questionnaire was sent to all US rehabilitation medicine training program directors. Results were compared with a survey conducted in 1985.

SETTING

US PM&R residency training programs with inpatient rehabilitation training.

PARTICIPANTS

Training directors or their designated agents.

INTERVENTION

A 35-item questionnaire was mailed between November 1999 and April 2000 to the 81 US training programs identified by the American Board of Physical Medicine and Rehabilitation as having rehabilitation training programs with inpatient rehabilitation units. Responses were pooled by our Survey Research Center to preserve anonymity. Training programs that did not respond received additional mailings and telephone calls to improve the response rate.

MAIN OUTCOME MEASURES

Chi-square analysis to assess changes in responses with time.

RESULTS

Forty-six of the 79 (58%) eligible training programs responded (1 program had merged, 1 did not provide inpatient rehabilitation). Programs were located in cities ranging from less than 100,000 (n = 2) to greater than a million inhabitants (n = 18). Eighty percent (37/46) of the respondents were "concerned or very concerned" about their patients' alcohol and drug use, and 69% routinely assessed patients for alcohol and drug use compared with only 25% in 1985 (P <.00001). Almost all respondents (43/46) supported written guidelines to prohibit alcohol and drug use by patients in the rehabilitation unit. Eighty-three percent had a prohibition policy, and 72% had written guidelines. Both of those rates represent increases from the 1985 response rates of 65% and 45%, respectively. Ambivalence persisted about appropriate treatment programs for persons with disabilities: in 1985, 51% of the respondents agreed that a person with a disability could be treated appropriately in a substance abuse program designed for persons without a disability; in 2000, the percentage had increased to 64%. All respondents believed that tobacco use is an addiction, but only 25% of their units offered tobacco cessation services to patients on their rehabilitation unit.

CONCLUSION

The survey results are encouraging. Since 1985, not only have substance abuse issues been recognized, but also systemic institutionalized approaches (eg, regular screening, written guidelines) have increased markedly. Tobacco is now uniformly accepted as an addiction, but screening and access to cessation programs are similar to that available for alcohol and drug treatment programs 15 years ago.

Nicotine dependence: studies with a laboratory model

Simple, rapid preclinical models of nicotine physical dependence and abstinence syndrome are needed to identify underlying neurobiological mechanisms and screen potential therapies. One such model induces dependence by 7 days of continuous subcutaneous nicotine infusion in the rat. Abstinence is initiated through termination of infusion or injection of nicotinic antagonist drugs. The result is an abstinence syndrome involving a pattern of behaviors somewhat resembling opiate abstinence in the rat as well as weight gain and depressed locomotor activity. The model has met a number of validity criteria and its essential features have been replicated in several laboratories. Several research groups have modified or extended the model by measuring emotional/motivational changes associated with nicotine abstinence such as conditioned aversion, intracranial self-stimulation (ICSS) thresholds and the startle response. Dependence models have been used to identify neurobiological systems that contribute to nicotine dependence, particularly endogenous opiate systems and the mesolimbic dopamine pathway. It is hypothesized that these different systems contribute to different behavioral aspects of nicotine abstinence syndrome. Increasingly used as a preclinical screening tool, the model has proved sensitive to various abstinence-alleviating therapeutic approaches, including some with already demonstrated clinical effectiveness.

Zyban: an effective treatment for nicotine addiction

Recent research has identified nicotine as a powerfully addictive substance. This article outlines how the new non-nicotine smoking cessation drug, Zyban, can help people to break the cycle of addiction and stop smoking.

The opioid antagonist naltrexone inhibits activity and alters expression of alpha7 and alpha4beta2 nicotinic receptors in hippocampal neurons: implications for smoking cessation programs

This study was designed to investigate whether naltrexone, an opioid antagonist that has been evaluated clinically as a co-adjuvant in smoking cessation programs, affects function and expression of neuronal nicotinic receptors (nAChRs). Whole-cell current recordings from rat hippocampal neurons in culture and in slices demonstrated that alpha7 nAChRs can be inhibited non-competitively by naltrexone (IC(50) approximately 25 microM). The voltage dependence of the effect suggested that naltrexone acts as an open-channel blocker of alpha7 nAChRs. Naltrexone also inhibited activation of alpha4beta2 nAChRs in hippocampal neurons; however its IC(50) was higher ( approximately 141 microM). At a concentration as high as 300 microM (which is sufficient to block by 100% and 70% the activity of alpha7 and alpha4beta2 nAChRs, respectively), naltrexone had no effect on kainate and AMPA receptors, blocked by no more than 20% the activity of NMDA and glycine receptors, and reduced by 35% the activity of GABA(A) receptors. A 3-day exposure of cultured hippocampal neurons to naltrexone (30 microM) or nicotine (10 microM, a concentration that fully desensitized alpha7 nAChRs) resulted in a 2-fold increase in the average amplitude of alpha7 nAChR-subserved currents. Naltrexone did not augment the maximal up-regulation of alpha7 nAChRs induced by nicotine, indicating that both drugs act via a common mechanism. In addition to increasing alpha7 nAChRs-mediated responses per neuron, nicotine increased the number of neurons expressing functional non-alpha7 nAChRs (probably alpha4beta2 nAChRs); this effect was blocked by naltrexone (0.3 and 30 microM). Therefore, naltrexone may affect dependence on cigarette smoking by differentially altering function and expression of alpha7 and alpha4beta2 nAChRs in the central nervous system.

Neuronal nicotinic receptors in synaptic functions in humans and rats: physiological and clinical relevance

The present report describes the participation of nicotinic receptors (nAChRs) in controlling the excitability of local neuronal circuitries in the rat hippocampus and in the human cerebral cortex. The patch-clamp technique was used to record responses triggered by the non-selective agonist ACh and the alpha7-nAChR-selective agonist choline in interneurons of human cerebral cortical and rat hippocampal slices. Evidence is provided that functional alpha7- and alpha4beta2-like nAChRs are present on somatodendritic and/or preterminal/terminal regions of interneurons in the CA1 field of the rat hippocampus and in the human cerebral cortex and that activation of the different nAChR subtypes present in the preterminal/terminal areas of the interneurons triggers the tetrodotoxin-sensitive release of GABA. Modulation by nAChRs of GABAergic transmission, which can result either in inhibition or disinhibition of pyramidal neurons, depends both on the receptor subtype present in the interneurons and on the agonist acting upon these receptors. Not only do alpha7 nAChRs desensitize faster than alpha4beta2 nAChRs, but also alpha7 nAChR desensitization induced by ACh lasts longer than that induced by choline. These mechanisms, which appear to be retained across species, might explain the involvement of nAChRs in cognitive functions and in such neurological disorders as Alzheimer's disease and schizophrenia.