Bupropion for Smoking Cessation

Obesity

Obesity is a common condition and a major cause of morbidity and mortality. Fortunately, weight loss treatment can reduce obesity-related complications. This review summarizes the evidence-based strategies physicians can employ to identify, prevent, and treat obesity, including best practices to diagnose and counsel patients, to assess and address the burden of weight-related disease including weight stigma, to address secondary causes of weight gain, and to help patients set individualized and realistic weight loss goals and an effective treatment plan. Effective treatments include lifestyle modification and adjunctive therapies such as antiobesity medications and metabolic and bariatric surgery.

The Role of Twice-Daily N-acetylcysteine (NAC) 2400 mg in Smoking Cessation: A Randomized, Placebo-Controlled Trial in Indonesia

INTRODUCTION

 Tobacco smoking remains a health concern, especially in developing countries. Nicotine is significantly linked to many cancers and even second-hand exposure. Hence, smoking can increase the risk of lung and heart disease. This makes quitting smoking important and challenging. Success tends to rise by achieving abstinence with assisted pharmacology. These treatments aim to reduce symptoms of nicotine withdrawal. This is a preclinical trial on glutamate modulator in N-acetylcysteine (NAC) as a new potential treatment for smoking cessation. It is based on the administration of NAC related to elevated levels of dopamine in the central nervous system to accomplish successful smoking cessation.

AIM

This study evaluated the efficacy and tolerability of NAC for smoking cessation. The primary outcome was abstinence rate and the secondary outcomes of the study were to assess carbon monoxide exhalation value (COexh), the withdrawal symptoms, craving score, safety, and tolerability associated with the administration of NAC.

METHODS

This is a randomized clinical trial. Eligible smokers were treated with NAC 2400 mg twice daily (BID) or placebo to obtain a potential effective abstinence rate. Subjects recruited from the smoking cessation clinic were screened for eligibility and were randomized to either the NAC or placebo group. The trial consisted of a four-week treatment phase and participants were evaluated each week with a brief counseling. Intention to treat data analysis was performed from 2018 to 2019. Smoking cessation status was verified by measuring the amount of carbon monoxide exhaled and by documenting their smoking habits. Adverse events (AEs) have also been observed on each visit.

RESULTS

A total of 90 male smokers with a mean (SD) age of 38.7 (11) years were randomized into two groups to receive NAC (n=45) and placebo (n=45). The primary outcome revealed that the abstinence rate was significantly higher for the NAC group than the placebo group (37.7% vs 6.6%; p=0.02). These findings were supported by data comparison between the NAC group and placebo group of COexh (ppm) (9.59 ±7.4 vs 13,4 ±6.1; p=0.04) and cigarette consumption/week (10 vs 46; p <0.001), which were statistically significant. Comparison of withdrawal with the Minnesota Nicotine Withdrawal Score between the NAC group and the placebo group showed lower values (8 (1-31) vs 11 (0-43); p=0.178), respectively, even though not statistically significant. Compared to the placebo group, the craving score (6 (2-29) vs 12 (6-31); p=0.04) in the NAC group was significantly lower. The most common adverse event was mild gastrointestinal effects (28.9%) and arthralgia (2.2%). No serious adverse events were detected.

CONCLUSIONS

 Despite a small sample size, the data demonstrate the potential benefits of NAC that may help elevate abstinence rates and promote successful smoking cessation pharmacotherapy. Comprehensive treatment combining pharmacologic therapy and counseling increases smoking cessation success rates. It is essential to conduct a randomized multicenter study with a large population to support a sustained abstinence rate using NAC.

New medications development for smoking cessation

Diseases associated with nicotine dependence in the form of habitual tobacco use are a major cause of premature death in the United States. The majority of tobacco smokers will relapse within the first month of attempted abstinence. Smoking cessation agents increase the likelihood that smokers can achieve long-term abstinence. Nevertheless, currently available smoking cessation agents have limited utility and fail to prevent relapse in the majority of smokers. Pharmacotherapy is therefore an effective strategy to aid smoking cessation efforts but considerable risk of relapse persists even when the most efficacious medications currently available are used. The past decade has seen major breakthroughs in our understanding of the molecular, cellular, and systems-level actions of nicotine in the brain that contribute to the development and maintenance of habitual tobacco use. In parallel, large-scale human genetics studies have revealed allelic variants that influence vulnerability to tobacco use disorder. These advances have revealed targets for the development of novel smoking cessation agents. Here, we summarize current efforts to develop smoking cessation therapeutics and highlight opportunities for future efforts.

Antidepressants for smoking cessation

BACKGROUND

The pharmacological profiles and mechanisms of antidepressants are varied. However, there are common reasons why they might help people to stop smoking tobacco: nicotine withdrawal can produce short-term low mood that antidepressants may relieve; and some antidepressants may have a specific effect on neural pathways or receptors that underlie nicotine addiction.

OBJECTIVES

To assess the evidence for the efficacy, harms, and tolerability of medications with antidepressant properties in assisting long-term tobacco smoking cessation in people who smoke cigarettes.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialised Register, most recently on 29 April 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in people who smoked, comparing antidepressant medications with placebo or no pharmacological treatment, an alternative pharmacotherapy, or the same medication used differently. We excluded trials with fewer than six months of follow-up from efficacy analyses. We included trials with any follow-up length for our analyses of harms.

DATA COLLECTION AND ANALYSIS

We extracted data and assessed risk of bias using standard Cochrane methods. Our primary outcome measure was smoking cessation after at least six months' follow-up. We used the most rigorous definition of abstinence available in each trial, and biochemically validated rates if available. Our secondary outcomes were harms and tolerance outcomes, including adverse events (AEs), serious adverse events (SAEs), psychiatric AEs, seizures, overdoses, suicide attempts, death by suicide, all-cause mortality, and trial dropouts due to treatment. We carried out meta-analyses where appropriate.

MAIN RESULTS

We included a total of 124 studies (48,832 participants) in this review, with 10 new studies added to this update version. Most studies recruited adults from the community or from smoking cessation clinics; four studies focused on adolescents (with participants between 12 and 21 years old). We judged 34 studies to be at high risk of bias; however, restricting analyses only to studies at low or unclear risk of bias did not change clinical interpretation of the results.  There was high-certainty evidence that bupropion increased smoking cessation rates when compared to placebo or no pharmacological treatment (RR 1.60, 95% CI 1.49 to 1.72; I2 = 16%; 50 studies, 18,577 participants). There was moderate-certainty evidence that a combination of bupropion and varenicline may have resulted in superior quit rates to varenicline alone (RR 1.21, 95% CI 0.95 to 1.55; I2 = 15%; 3 studies, 1057 participants). However, there was insufficient evidence to establish whether a combination of bupropion and nicotine replacement therapy (NRT) resulted in superior quit rates to NRT alone (RR 1.17, 95% CI 0.95 to 1.44; I2 = 43%; 15 studies, 4117 participants; low-certainty evidence). There was moderate-certainty evidence that participants taking bupropion were more likely to report SAEs than those taking placebo or no pharmacological treatment. However, results were imprecise and the CI also encompassed no difference (RR 1.16, 95% CI 0.90 to 1.48; I2 = 0%; 23 studies, 10,958 participants). Results were also imprecise when comparing SAEs between people randomised to a combination of bupropion and NRT versus NRT alone (RR 1.52, 95% CI 0.26 to 8.89; I2 = 0%; 4 studies, 657 participants) and randomised to bupropion plus varenicline versus varenicline alone (RR 1.23, 95% CI 0.63 to 2.42; I2 = 0%; 5 studies, 1268 participants). In both cases, we judged evidence to be of low certainty. There was high-certainty evidence that bupropion resulted in more trial dropouts due to AEs than placebo or no pharmacological treatment (RR 1.44, 95% CI 1.27 to 1.65; I2 = 2%; 25 studies, 12,346 participants). However, there was insufficient evidence that bupropion combined with NRT versus NRT alone (RR 1.67, 95% CI 0.95 to 2.92; I2 = 0%; 3 studies, 737 participants) or bupropion combined with varenicline versus varenicline alone (RR 0.80, 95% CI 0.45 to 1.45; I2 = 0%; 4 studies, 1230 participants) had an impact on the number of dropouts due to treatment. In both cases, imprecision was substantial (we judged the evidence to be of low certainty for both comparisons). Bupropion resulted in inferior smoking cessation rates to varenicline (RR 0.73, 95% CI 0.67 to 0.80; I2 = 0%; 9 studies, 7564 participants), and to combination NRT (RR 0.74, 95% CI 0.55 to 0.98; I2 = 0%; 2 studies; 720 participants). However, there was no clear evidence of a difference in efficacy between bupropion and single-form NRT (RR 1.03, 95% CI 0.93 to 1.13; I2 = 0%; 10 studies, 7613 participants). We also found evidence that nortriptyline aided smoking cessation when compared with placebo (RR 2.03, 95% CI 1.48 to 2.78; I2 = 16%; 6 studies, 975 participants), and some evidence that bupropion resulted in superior quit rates to nortriptyline (RR 1.30, 95% CI 0.93 to 1.82; I2 = 0%; 3 studies, 417 participants), although this result was subject to imprecision. Findings were sparse and inconsistent as to whether antidepressants, primarily bupropion and nortriptyline, had a particular benefit for people with current or previous depression.

AUTHORS' CONCLUSIONS

There is high-certainty evidence that bupropion can aid long-term smoking cessation. However, bupropion may increase SAEs (moderate-certainty evidence when compared to placebo/no pharmacological treatment). There is high-certainty evidence that people taking bupropion are more likely to discontinue treatment compared with people receiving placebo or no pharmacological treatment. Nortriptyline also appears to have a beneficial effect on smoking quit rates relative to placebo, although bupropion may be more effective. Evidence also suggests that bupropion may be as successful as single-form NRT in helping people to quit smoking, but less effective than combination NRT and varenicline. In most cases, a paucity of data made it difficult to draw conclusions regarding harms and tolerability. Further studies investigating the efficacy of bupropion versus placebo are unlikely to change our interpretation of the effect, providing no clear justification for pursuing bupropion for smoking cessation over other licensed smoking cessation treatments; namely, NRT and varenicline. However, it is important that future studies of antidepressants for smoking cessation measure and report on harms and tolerability.

Smoking cessation medicines and e-cigarettes: a systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

Cigarette smoking is one of the leading causes of early death. Varenicline [Champix (UK), Pfizer Europe MA EEIG, Brussels, Belgium; or Chantix (USA), Pfizer Inc., Mission, KS, USA], bupropion (Zyban; GlaxoSmithKline, Brentford, UK) and nicotine replacement therapy are licensed aids for quitting smoking in the UK. Although not licensed, e-cigarettes may also be used in English smoking cessation services. Concerns have been raised about the safety of these medicines and e-cigarettes.

OBJECTIVES

To determine the clinical effectiveness, safety and cost-effectiveness of smoking cessation medicines and e-cigarettes.

DESIGN

Systematic reviews, network meta-analyses and cost-effectiveness analysis informed by the network meta-analysis results.

SETTING

Primary care practices, hospitals, clinics, universities, workplaces, nursing or residential homes.

PARTICIPANTS

Smokers aged ≥ 18 years of all ethnicities using UK-licensed smoking cessation therapies and/or e-cigarettes.

INTERVENTIONS

Varenicline, bupropion and nicotine replacement therapy as monotherapies and in combination treatments at standard, low or high dose, combination nicotine replacement therapy and e-cigarette monotherapies.

MAIN OUTCOME MEASURES

Effectiveness - continuous or sustained abstinence. Safety - serious adverse events, major adverse cardiovascular events and major adverse neuropsychiatric events.

DATA SOURCES

Ten databases, reference lists of relevant research articles and previous reviews. Searches were performed from inception until 16 March 2017 and updated on 19 February 2019.

REVIEW METHODS

Three reviewers screened the search results. Data were extracted and risk of bias was assessed by one reviewer and checked by the other reviewers. Network meta-analyses were conducted for effectiveness and safety outcomes. Cost-effectiveness was evaluated using an amended version of the Benefits of Smoking Cessation on Outcomes model.

RESULTS

Most monotherapies and combination treatments were more effective than placebo at achieving sustained abstinence. Varenicline standard plus nicotine replacement therapy standard (odds ratio 5.75, 95% credible interval 2.27 to 14.90) was ranked first for sustained abstinence, followed by e-cigarette low (odds ratio 3.22, 95% credible interval 0.97 to 12.60), although these estimates have high uncertainty. We found effect modification for counselling and dependence, with a higher proportion of smokers who received counselling achieving sustained abstinence than those who did not receive counselling, and higher odds of sustained abstinence among participants with higher average dependence scores. We found that bupropion standard increased odds of serious adverse events compared with placebo (odds ratio 1.27, 95% credible interval 1.04 to 1.58). There were no differences between interventions in terms of major adverse cardiovascular events. There was evidence of increased odds of major adverse neuropsychiatric events for smokers randomised to varenicline standard compared with those randomised to bupropion standard (odds ratio 1.43, 95% credible interval 1.02 to 2.09). There was a high level of uncertainty about the most cost-effective intervention, although all were cost-effective compared with nicotine replacement therapy low at the £20,000 per quality-adjusted life-year threshold. E-cigarette low appeared to be most cost-effective in the base case, followed by varenicline standard plus nicotine replacement therapy standard. When the impact of major adverse neuropsychiatric events was excluded, varenicline standard plus nicotine replacement therapy standard was most cost-effective, followed by varenicline low plus nicotine replacement therapy standard. When limited to licensed interventions in the UK, nicotine replacement therapy standard was most cost-effective, followed by varenicline standard.

LIMITATIONS

Comparisons between active interventions were informed almost exclusively by indirect evidence. Findings were imprecise because of the small numbers of adverse events identified.

CONCLUSIONS

Combined therapies of medicines are among the most clinically effective, safe and cost-effective treatment options for smokers. Although the combined therapy of nicotine replacement therapy and varenicline at standard doses was the most effective treatment, this is currently unlicensed for use in the UK.

FUTURE WORK

Researchers should examine the use of these treatments alongside counselling and continue investigating the long-term effectiveness and safety of e-cigarettes for smoking cessation compared with active interventions such as nicotine replacement therapy.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016041302.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 59. See the NIHR Journals Library website for further project information.

Interventions for preventing weight gain after smoking cessation

BACKGROUND

Most people who stop smoking gain weight. This can discourage some people from making a quit attempt and risks offsetting some, but not all, of the health advantages of quitting. Interventions to prevent weight gain could improve health outcomes, but there is a concern that they may undermine quitting.

OBJECTIVES

To systematically review the effects of: (1) interventions targeting post-cessation weight gain on weight change and smoking cessation (referred to as 'Part 1') and (2) interventions designed to aid smoking cessation that plausibly affect post-cessation weight gain (referred to as 'Part 2').

SEARCH METHODS

Part 1 - We searched the Cochrane Tobacco Addiction Group's Specialized Register and CENTRAL; latest search 16 October 2020. Part 2 - We searched included studies in the following 'parent' Cochrane reviews: nicotine replacement therapy (NRT), antidepressants, nicotine receptor partial agonists, e-cigarettes, and exercise interventions for smoking cessation published in Issue 10, 2020 of the Cochrane Library. We updated register searches for the review of nicotine receptor partial agonists.

SELECTION CRITERIA

Part 1 - trials of interventions that targeted post-cessation weight gain and had measured weight at any follow-up point or smoking cessation, or both, six or more months after quit day. Part 2 - trials included in the selected parent Cochrane reviews reporting weight change at any time point.

DATA COLLECTION AND ANALYSIS

Screening and data extraction followed standard Cochrane methods. Change in weight was expressed as difference in weight change from baseline to follow-up between trial arms and was reported only in people abstinent from smoking. Abstinence from smoking was expressed as a risk ratio (RR). Where appropriate, we performed meta-analysis using the inverse variance method for weight, and Mantel-Haenszel method for smoking.

MAIN RESULTS

Part 1: We include 37 completed studies; 21 are new to this update. We judged five studies to be at low risk of bias, 17 to be at unclear risk and the remainder at high risk.  An intermittent very low calorie diet (VLCD) comprising full meal replacement provided free of charge and accompanied by intensive dietitian support significantly reduced weight gain at end of treatment compared with education on how to avoid weight gain (mean difference (MD) -3.70 kg, 95% confidence interval (CI) -4.82 to -2.58; 1 study, 121 participants), but there was no evidence of benefit at 12 months (MD -1.30 kg, 95% CI -3.49 to 0.89; 1 study, 62 participants). The VLCD increased the chances of abstinence at 12 months (RR 1.73, 95% CI 1.10 to 2.73; 1 study, 287 participants). However, a second study  found that no-one completed the VLCD intervention or achieved abstinence. Interventions aimed at increasing acceptance of weight gain reported mixed effects at end of treatment, 6 months and 12 months with confidence intervals including both increases and decreases in weight gain compared with no advice or health education. Due to high heterogeneity, we did not combine the data. These interventions increased quit rates at 6 months (RR 1.42, 95% CI 1.03 to 1.96; 4 studies, 619 participants; I² = 21%), but there was no evidence at 12 months (RR 1.25, 95% CI 0.76 to 2.06; 2 studies, 496 participants; I² = 26%). Some pharmacological interventions tested for limiting post-cessation weight gain (PCWG) reduced weight gain at the end of treatment (dexfenfluramine, phenylpropanolamine, naltrexone). The effects of ephedrine and caffeine combined, lorcaserin, and chromium were too imprecise to give useful estimates of treatment effects. There was very low-certainty evidence that personalized weight management support reduced weight gain at end of treatment (MD -1.11 kg, 95% CI -1.93 to -0.29; 3 studies, 121 participants; I² = 0%), but no evidence in the longer-term 12 months (MD -0.44 kg, 95% CI -2.34 to 1.46; 4 studies, 530 participants; I² = 41%). There was low to very low-certainty evidence that detailed weight management education without personalized assessment, planning and feedback did not reduce weight gain and may have reduced smoking cessation rates (12 months: MD -0.21 kg, 95% CI -2.28 to 1.86; 2 studies, 61 participants; I² = 0%; RR for smoking cessation 0.66, 95% CI 0.48 to 0.90; 2 studies, 522 participants; I² = 0%). Part 2: We include 83 completed studies, 27 of which are new to this update. There was low certainty that exercise interventions led to minimal or no weight reduction compared with standard care at end of treatment (MD -0.25 kg, 95% CI -0.78 to 0.29; 4 studies, 404 participants; I² = 0%). However, weight was reduced at 12 months (MD -2.07 kg, 95% CI -3.78 to -0.36; 3 studies, 182 participants; I² = 0%). Both bupropion and fluoxetine limited weight gain at end of treatment (bupropion MD -1.01 kg, 95% CI -1.35 to -0.67; 10 studies, 1098 participants; I² = 3%); (fluoxetine MD -1.01 kg, 95% CI -1.49 to -0.53; 2 studies, 144 participants; I² = 38%; low- and very low-certainty evidence, respectively). There was no evidence of benefit at 12 months for bupropion, but estimates were imprecise (bupropion MD -0.26 kg, 95% CI -1.31 to 0.78; 7 studies, 471 participants; I² = 0%). No studies of fluoxetine provided data at 12 months. There was moderate-certainty that NRT reduced weight at end of treatment (MD -0.52 kg, 95% CI -0.99 to -0.05; 21 studies, 2784 participants; I² = 81%) and moderate-certainty that the effect may be similar at 12 months (MD -0.37 kg, 95% CI -0.86 to 0.11; 17 studies, 1463 participants; I² = 0%), although the estimates are too imprecise to assess long-term benefit. There was mixed evidence of the effect of varenicline on weight, with high-certainty evidence that weight change was very modestly lower at the end of treatment (MD -0.23 kg, 95% CI -0.53 to 0.06; 14 studies, 2566 participants; I² = 32%); a low-certainty estimate gave an imprecise estimate of higher weight at 12 months (MD 1.05 kg, 95% CI -0.58 to 2.69; 3 studies, 237 participants; I² = 0%).

AUTHORS' CONCLUSIONS

Overall, there is no intervention for which there is moderate certainty of a clinically useful effect on long-term weight gain. There is also no moderate- or high-certainty evidence that interventions designed to limit weight gain reduce the chances of people achieving abstinence from smoking.

Dynamic associations between anxiety, depression, and tobacco use in older adults: Results from The Irish Longitudinal Study on Ageing

Evidence supports moderate-to-large reductions in anxiety, depression, and perceived stress after smoking cessation; however, much of the available evidence has focused on young adults. Therefore, this study quantified associations between smoking and smoking cessation on prevalent and incident generalised anxiety disorder (GAD) and major depression (MDD) in a nationally representative sample of Irish older adults. Participants (n = 6201) were community dwelling adults aged ≥50 years resident in Ireland. Smoking status and self-reported doctor diagnosis of anxiety or depression prior to baseline were assessed at baseline (i.e., Wave 2). At baseline and 2-, 4-, and 6-year follow-up (i.e., Waves 3-5), GAD and MDD were assessed by the Composite International Diagnostic Interview Short-Form. Logistic regression quantified cross-sectional and prospective associations (odds ratios (ORs) and 95% confidence intervals (95%CIs)) between smoking status and mental health. Prevalence and incidence of GAD was 9.1% (n = 566) and 2.8% (n = 148), respectively. Prevalence and incidence of depression was 11.1% (n = 686) and 6.4% (n = 342), respectively. Following full adjustment, current smokers had higher odds of prevalent GAD (OR = 1.729, 1.332-2.449; p < 0.001) and MDD (OR = 1.967, 1.548-2.499; p < 0.001) than non-smokers. Former smokers had higher odds of prevalent GAD than non-smokers (OR = 1.276, 1.008-1.616; p < 0.001). Current smokers did not have higher odds of incident MDD (OR = 1.399, 0.984-1.990; p = 0.065) or GAD than non-smokers (1.039, 0.624-1.730; p = 0.881). Findings may have important implications for interventions designed to curb tobacco abuse, which tend to be less successful among those with anxiety and depression.

[Smoking cessation in asthmatic patients and its impact]

INTRODUCTION

The prevalence of smoking in asthmatic patients is similar to, or even higher than in the general population.

OBJECTIVES

This systematic review addresses (1) the effects of smoking on asthma, (2) smoking cessation strategies in asthmatic patients, and (3) the consequences of smoking cessation for people with asthma.

RESULTS

Active or passive smoking can promote the development of asthma. The few studies on smoking cessation in asthma confirm the efficacy of validated smoking cessation strategies in these patients (nicotine replacement therapy, varenicline, bupropion, cognitive and behavioural therapies). Smoking cessation in parents with asthmatic children is essential and is based on the same strategies. Electronic cigarettes may be a useful help to quit smoking in some patients. Smoking cessation is beneficial in asthmatic smokers and associated with (1) a reduction of asthma symptoms, acute exacerbations, bronchial hyperresponsiveness, and bronchial inflammation, (2) decreased use of rescue medications and in doses of inhaled corticosteroids, (3) improved asthma control, quality of life, and lung function.

CONCLUSION

In asthmatic patients, it is essential to assess smoking status and health professionals must assist them to quit smoking.

Antidepressants for smoking cessation

BACKGROUND

Whilst the pharmacological profiles and mechanisms of antidepressants are varied, there are common reasons why they might help people to stop smoking tobacco. Firstly, nicotine withdrawal may produce depressive symptoms and antidepressants may relieve these. Additionally, some antidepressants may have a specific effect on neural pathways or receptors that underlie nicotine addiction.

OBJECTIVES

To assess the evidence for the efficacy, safety and tolerability of medications with antidepressant properties in assisting long-term tobacco smoking cessation in people who smoke cigarettes.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Specialized Register, which includes reports of trials indexed in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO, clinicaltrials.gov, the ICTRP, and other reviews and meeting abstracts, in May 2019.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that recruited smokers, and compared antidepressant medications with placebo or no treatment, an alternative pharmacotherapy, or the same medication used in a different way. We excluded trials with less than six months follow-up from efficacy analyses. We included trials with any follow-up length in safety analyses.

DATA COLLECTION AND ANALYSIS

We extracted data and assessed risk of bias using standard Cochrane methods. We also used GRADE to assess the certainty of the evidence. The primary outcome measure was smoking cessation after at least six months follow-up, expressed as a risk ratio (RR) and 95% confidence intervals (CIs). We used the most rigorous definition of abstinence available in each trial, and biochemically validated rates if available. Where appropriate, we performed meta-analysis using a fixed-effect model. Similarly, we presented incidence of safety and tolerance outcomes, including adverse events (AEs), serious adverse events (SAEs), psychiatric AEs, seizures, overdoses, suicide attempts, death by suicide, all-cause mortality, and trial dropout due to drug, as RRs (95% CIs).

MAIN RESULTS

We included 115 studies (33 new to this update) in this review; most recruited adult participants from the community or from smoking cessation clinics. We judged 28 of the studies to be at high risk of bias; however, restricting analyses only to studies at low or unclear risk did not change clinical interpretation of the results. There was high-certainty evidence that bupropion increased long-term smoking cessation rates (RR 1.64, 95% CI 1.52 to 1.77; I² = 15%; 45 studies, 17,866 participants). There was insufficient evidence to establish whether participants taking bupropion were more likely to report SAEs compared to those taking placebo. Results were imprecise and CIs encompassed no difference (RR 1.16, 95% CI 0.90 to 1.48; I² = 0%; 21 studies, 10,625 participants; moderate-certainty evidence, downgraded one level due to imprecision). We found high-certainty evidence that use of bupropion resulted in more trial dropouts due to adverse events of the drug than placebo (RR 1.37, 95% CI 1.21 to 1.56; I² = 19%; 25 studies, 12,340 participants). Participants randomized to bupropion were also more likely to report psychiatric AEs compared with those randomized to placebo (RR 1.25, 95% CI 1.15 to 1.37; I² = 15%; 6 studies, 4439 participants). We also looked at the safety and efficacy of bupropion when combined with other non-antidepressant smoking cessation therapies. There was insufficient evidence to establish whether combination bupropion and nicotine replacement therapy (NRT) resulted in superior quit rates to NRT alone (RR 1.19, 95% CI 0.94 to 1.51; I² = 52%; 12 studies, 3487 participants), or whether combination bupropion and varenicline resulted in superior quit rates to varenicline alone (RR 1.21, 95% CI 0.95 to 1.55; I² = 15%; 3 studies, 1057 participants). We judged the certainty of evidence to be low and moderate, respectively; in both cases due to imprecision, and also due to inconsistency in the former. Safety data were sparse for these comparisons, making it difficult to draw clear conclusions. A meta-analysis of six studies provided evidence that bupropion resulted in inferior smoking cessation rates to varenicline (RR 0.71, 95% CI 0.64 to 0.79; I² = 0%; 6 studies, 6286 participants), whilst there was no evidence of a difference in efficacy between bupropion and NRT (RR 0.99, 95% CI 0.91 to 1.09; I² = 18%; 10 studies, 8230 participants). We also found some evidence that nortriptyline aided smoking cessation when compared with placebo (RR 2.03, 95% CI 1.48 to 2.78; I² = 16%; 6 studies, 975 participants), whilst there was insufficient evidence to determine whether bupropion or nortriptyline were more effective when compared with one another (RR 1.30 (favouring bupropion), 95% CI 0.93 to 1.82; I² = 0%; 3 studies, 417 participants). There was no evidence that any of the other antidepressants tested (including St John's Wort, selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase inhibitors (MAOIs)) had a beneficial effect on smoking cessation. Findings were sparse and inconsistent as to whether antidepressants, primarily bupropion and nortriptyline, had a particular benefit for people with current or previous depression.

AUTHORS' CONCLUSIONS

There is high-certainty evidence that bupropion can aid long-term smoking cessation. However, bupropion also increases the number of adverse events, including psychiatric AEs, and there is high-certainty evidence that people taking bupropion are more likely to discontinue treatment compared with placebo. However, there is no clear evidence to suggest whether people taking bupropion experience more or fewer SAEs than those taking placebo (moderate certainty). Nortriptyline also appears to have a beneficial effect on smoking quit rates relative to placebo. Evidence suggests that bupropion may be as successful as NRT and nortriptyline in helping people to quit smoking, but that it is less effective than varenicline. There is insufficient evidence to determine whether the other antidepressants tested, such as SSRIs, aid smoking cessation, and when looking at safety and tolerance outcomes, in most cases, paucity of data made it difficult to draw conclusions. Due to the high-certainty evidence, further studies investigating the efficacy of bupropion versus placebo are unlikely to change our interpretation of the effect, providing no clear justification for pursuing bupropion for smoking cessation over front-line smoking cessation aids already available. However, it is important that where studies of antidepressants for smoking cessation are carried out they measure and report safety and tolerability clearly.

Off-label uses of drugs for depression

The prescription of drugs for depression is rising rapidly. One of the reasons for this trend is their many off-label uses. Up to one third of all prescriptions are for non-indicated use, which in addition to drug repurposing includes different dosing or duration than those recommended. In this review, we elaborate on what antidepressants can treat besides depression. The five classes of drugs for depression are introduced, and their mechanisms of action and serious side effects are described. The most common off-label uses of antidepressants are discussed, with a special focus on treating eating disorders, sleep problems, smoking cessation and managing chronic pain. Depression is often a comorbidity when antidepressants are chosen as therapy, but good therapeutic effects have been observed for other conditions also when depression is not involved. Finally, a new type of antidepressant developed from the hallucinogenic "party drug" ketamine is briefly introduced. This recent development suggests that antidepressants will keep playing a central role in medicine for years to come.

Why are Antidepressant Drugs Effective Smoking Cessation Aids?

BACKGROUND

Before the advent of varenicline, antidepressant drugs were reported to exhibit better clinical efficacy than nicotine replacement therapy as smoking cessation aids. The most studied is bupropion, a clinically-effective antidepressant, the first to be marketed throughout Europe for smoking cessation. Since depression and tobacco smoking have a high incidence of cooccurrence, this would implicate an underlying link between these two conditions. If this correlation can be confirmed, then by treating one condition the related state would also be treated.

OBJECTIVES

This review article will evaluate the various theories relating to the use of antidepressant drugs as smoking cessation aids and the underlying mechanisms link tobacco smoking and depression to explain the action of antidepressants in smoking cessation. One plausible theory of self-medication which proposes that people take nicotine to treat their own depressive symptoms and the affective withdrawal symptoms seen with abstinence from the drug. If the depression can instead be treated with antidepressants, then they may stop smoking altogether. Another theory is that the neurobiological pathways underlying smoking and depression may be similar. By targeting the pathways of depression in the brain, antidepressants would also treat the pathways affected by smoking and ease nicotine cravings and withdrawal. The role of genetic variation predisposing an individual to depression and initiation of tobacco smoking has also been discussed as a potential link between the two conditions. Such variation could either occur within the neurobiological pathways involved in both disorders or it could lead to an individual being depressed and selfmedicating with nicotine.

Combination Therapies for Smoking Cessation: A Hierarchical Bayesian Meta-Analysis

CONTEXT

Treatment guidelines recommend the use of combination therapies for smoking cessation, particularly behavioral therapy (BT) as an adjunct to pharmacotherapy. However, these guidelines rely on previous reviews with important limitations. This study's objective was to evaluate the efficacy of combination therapies compared with monotherapies, using the most rigorous data available.

EVIDENCE ACQUISITION

A systematic review and meta-analysis of RCTs of pharmacotherapies, BTs, or both were conducted. The Cochrane Library, Embase, PsycINFO, and PubMed databases were systematically searched from inception to July 2015. Inclusion was restricted to RCTs reporting biochemically validated abstinence at 12 months. Direct and indirect comparisons were made in 2015 between therapies using hierarchical Bayesian models.

EVIDENCE SYNTHESIS

The search identified 123 RCTs meeting inclusion criteria (60,774 participants), and data from 115 (57,851 participants) were meta-analyzed. Varenicline with BT increased abstinence more than other combinations of a pharmacotherapy with BT (varenicline versus bupropion: OR=1.56, 95% credible interval [CrI]=1.07, 2.34; varenicline versus nicotine patch: OR=1.65, 95% CrI=1.10, 2.51; varenicline versus short-acting nicotine-replacement therapies: OR=1.68, 95% CrI=1.15, 2.53). Adding BT to any pharmacotherapy compared with pharmacotherapy alone was inconclusive, owing to wide CrIs (OR=1.17, CrI=0.60, 2.12). Nicotine patch with short-acting nicotine-replacement therapy appears safe and increases abstinence versus nicotine-replacement monotherapy (OR=1.63, CrI=1.06, 3.03). Data are limited concerning other pharmacotherapy combinations and their safety and tolerability.

CONCLUSIONS

Evidence suggests that combination therapy benefits may be less than previously thought. Combined with BT, varenicline increases abstinence more than other pharmacotherapy with BT combinations.

Combination treatment with varenicline and bupropion in an adaptive smoking cessation paradigm

OBJECTIVE

The authors assessed the efficacy and safety of combination treatment with varenicline and sustained-release bupropion for smokers who, based on an assessment of initial smoking reduction prior to the quit date, were deemed unlikely to achieve abstinence using nicotine patch treatment.

METHOD

In a randomized, double-blind, parallel-group adaptive treatment trial, the authors identified 222 cigarette smokers who failed to show a reduction of more than 50% in smoking after 1 week of nicotine patch treatment. Smokers were randomly assigned to receive 12 weeks of varenicline plus bupropion or varenicline plus placebo. The primary outcome measure was continuous smoking abstinence at weeks 8-11 after the target quit date.

RESULTS

Both treatments were well tolerated. Participants who received the combination treatment had a significantly higher abstinence rate than those who received varenicline plus placebo (39.8% compared with 25.9%; odds ratio=1.89; 95% CI=1.07, 3.35). Combination treatment had a significantly greater effect on abstinence rate in male smokers (odds ratio=4.26; 95% CI=1.73, 10.49) than in female smokers (odds ratio=0.94; 95% CI=0.43, 2.05). It also had a significantly greater effect in highly nicotine-dependent smokers (odds ratio=3.51, 95% CI=1.64, 7.51) than in smokers with lower levels of dependence (odds ratio=0.71, 95% CI=0.28, 1.80).

CONCLUSIONS

Among smokers who did not show a sufficient initial response to prequit nicotine patch treatment, combination treatment with varenicline and bupropion proved more efficacious than varenicline alone for male smokers and for smokers with a high degree of nicotine dependence.

Association between cigarette smoking history and mortality in 36,446 health examinees in Korea

BACKGROUND

It is well known that smoking is a preventable factor for all-cause mortality; however, it is still questionable how many years after smoking cessation that people will have reduced risk for mortality, in particular in those with a high interest in their own health. We aimed to examine the association between time since quitting smoking and total mortality among past-smokers relative to current smokers.

MATERIALS AND METHODS

We enrolled 36,446 health examinees that voluntarily taken with diverse health check-up packages of high cost burden in 1995-2003 and followed them till death by 2004. The history of cigarette smoking consumption was collected using a self-administrative questionnaire at the first visit time. Mortality risk by smoking cessation years was analyzed using Cox's proportional hazard model.

RESULTS

Compared to non-smokers, male smokers over 15 pack-years had higher risk for total mortality (HR=1.49, 95%CI 1.02-2.18). The mortality risk in female smokers with same pack-years was more pronounced than that in male smokers (HR=2.83, 95%CI 1.17-7.04) despite a small number of cases. Compared to current smokers, a decrease of total mortality was observed among those who ceased smoking, and inverse dose-response was found with years after cessation: RR 0.98 (95%CI, 0.64-1.41) (<2 yrs), 0.60 (95%CI, 0.43-0.83) (3-9 yrs), and 0.58 (95%CI, 0.43-0.79) (≥10 yrs).

CONCLUSIONS

A reduced risk of total mortality was observed after 3 years of smoking cessation. Our findings suggest that at least 3 years of smoking cessation may contribute to reduce premature mortality among Asian men.

Clinical strategies to enhance the efficacy of nicotine replacement therapy for smoking cessation: a review of the literature

A number of smoking cessation pharmacotherapies have led to increases in quitting and thus to significant benefits to public health. Among existing medications, nicotine replacement therapy (NRT) has been available the longest, has the largest literature base in support, and is the only option for over-the-counter access. While the short-term efficacy of NRT is well documented in clinical trials, long-term abstinence rates associated with using NRT are modest, as most smokers will relapse. This literature review examines emerging clinical strategies to improve NRT efficacy. After an initial overview of NRT and its FDA-approved indications for use, we review randomized trials in which clinical delivery of NRT was manipulated and tested, in an attempt to enhance efficacy, through (1) duration of use (pre-quit and extended use), (2) amount of use (high-dose and combination NRT), (3) tailoring to specific smoker groups (genotype and phenotype), or (4) use of NRT for novel purposes (relapse prevention, temporary abstinence, cessation induction). Outcomes vary within and across topic area, and we highlight areas that offer stronger promise. Combination NRT likely represents the most promising strategy moving forward; other clinical strategies offer conflicting evidence but deserve further testing (pre-quit NRT or tailored treatment) or offer potential utility but are in need of further, direct tests. Some areas, though based on a limited set of studies, do not offer great promise (high-dose and extended treatment NRT). We conclude with a brief discussion of emergent NRT products (e.g., oral nicotine spray, among others), which may ultimately offer greater efficacy than current formulations. In order to further lower the prevalence of smoking, novel strategies designed to optimize NRT efficacy are needed.

Bupropion: pharmacology and therapeutic applications

A total of 17 years after its introduction, bupropion remains a safe and effective antidepressant, suitable for first-line use. Bupropion undergoes metabolic transformation to an active metabolite, 4-hydroxybupropion, through hepatic cytochrome P450-2B6 (CYP2B6) and has inhibitory effects on cytochrome P450-2D6 (CYP2D6), thus raising concern for clinically-relevant drug interactions. Common side effects are nervousness and insomnia. Nausea appears slightly less common than with the SSRI drugs and sexual dysfunction is probably the least of any antidepressant. Bupropion is relatively safe in overdose with seizures being the predominant concern. The mechanism of action of bupropion is still uncertain but may be related to inhibition of presynaptic dopamine and norepinephrine reuptake transporters. The activity of vesicular monoamine transporter-2, the transporter pumping dopamine, norepinephrine and serotonin from the cytosol into presynaptic vesicles, is increased by bupropion and may be a component of its mechanism of action. Bupropion is approved for use in major depression and seasonal affective disorder and has demonstrated comparable efficacy to other antidepressants in clinical trials. Bupropion is also useful in augmenting a partial response to selective serotonin reuptake inhibitor antidepressants, although bupropion should not be combined with monoamine oxidase inhibitors. It may be less likely to provoke mania than antidepressants with prominent serotonergic effects. Bupropion is effective in helping people quit tobacco smoking. Anecdotal reports indicate bupropion may lower inflammatory mediators such as tumor necrosis factor-alpha, may lower fatigue in cancer and may help reduce concentration problems.

Antidepressants for smoking cessation

BACKGROUND

There are at least three reasons to believe antidepressants might help in smoking cessation. Firstly, nicotine withdrawal may produce depressive symptoms or precipitate a major depressive episode and antidepressants may relieve these. Secondly, nicotine may have antidepressant effects that maintain smoking, and antidepressants may substitute for this effect. Finally, some antidepressants may have a specific effect on neural pathways (e.g. inhibiting monoamine oxidase) or receptors (e.g. blockade of nicotinic-cholinergic receptors) underlying nicotine addiction.

OBJECTIVES

The aim of this review is to assess the effect and safety of antidepressant medications to aid long-term smoking cessation. The medications include bupropion; doxepin; fluoxetine; imipramine; lazabemide; moclobemide; nortriptyline; paroxetine; S-Adenosyl-L-Methionine (SAMe); selegiline; sertraline; St. John's wort; tryptophan; venlafaxine; and zimeledine.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialised Register which includes reports of trials indexed in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and PsycINFO, and other reviews and meeting abstracts, in July 2013.

SELECTION CRITERIA

We considered randomized trials comparing antidepressant medications to placebo or an alternative pharmacotherapy for smoking cessation. We also included trials comparing different doses, using pharmacotherapy to prevent relapse or re-initiate smoking cessation or to help smokers reduce cigarette consumption. We excluded trials with less than six months follow-up.

DATA COLLECTION AND ANALYSIS

We extracted data and assessed risk of bias using standard methodological procedures expected by the Cochrane Collaboration.The main outcome measure was abstinence from smoking after at least six months follow-up in patients smoking at baseline, expressed as a risk ratio (RR). We used the most rigorous definition of abstinence available in each trial, and biochemically validated rates if available. Where appropriate, we performed meta-analysis using a fixed-effect model.

MAIN RESULTS

Twenty-four new trials were identified since the 2009 update, bringing the total number of included trials to 90. There were 65 trials of bupropion and ten trials of nortriptyline, with the majority at low or unclear risk of bias. There was high quality evidence that, when used as the sole pharmacotherapy, bupropion significantly increased long-term cessation (44 trials, N = 13,728, risk ratio [RR] 1.62, 95% confidence interval [CI] 1.49 to 1.76). There was moderate quality evidence, limited by a relatively small number of trials and participants, that nortriptyline also significantly increased long-term cessation when used as the sole pharmacotherapy (six trials, N = 975, RR 2.03, 95% CI 1.48 to 2.78). There is insufficient evidence that adding bupropion (12 trials, N = 3487, RR 1.9, 95% CI 0.94 to 1.51) or nortriptyline (4 trials, N = 1644, RR 1.21, 95% CI 0.94 to 1.55) to nicotine replacement therapy (NRT) provides an additional long-term benefit. Based on a limited amount of data from direct comparisons, bupropion and nortriptyline appear to be equally effective and of similar efficacy to NRT (bupropion versus nortriptyline 3 trials, N = 417, RR 1.30, 95% CI 0.93 to 1.82; bupropion versus NRT 8 trials, N = 4096, RR 0.96, 95% CI 0.85 to 1.09; no direct comparisons between nortriptyline and NRT). Pooled results from four trials comparing bupropion to varenicline showed significantly lower quitting with bupropion than with varenicline (N = 1810, RR 0.68, 95% CI 0.56 to 0.83). Meta-analyses did not detect a significant increase in the rate of serious adverse events amongst participants taking bupropion, though the confidence interval only narrowly missed statistical significance (33 trials, N = 9631, RR 1.30, 95% CI 1.00 to 1.69). There is a risk of about 1 in 1000 of seizures associated with bupropion use. Bupropion has been associated with suicide risk, but whether this is causal is unclear. Nortriptyline has the potential for serious side-effects, but none have been seen in the few small trials for smoking cessation.There was no evidence of a significant effect for selective serotonin reuptake inhibitors on their own (RR 0.93, 95% CI 0.71 to 1.22, N = 1594; 2 trials fluoxetine, 1 paroxetine, 1 sertraline) or as an adjunct to NRT (3 trials of fluoxetine, N = 466, RR 0.70, 95% CI 0.64 to 1.82). Significant effects were also not detected for monoamine oxidase inhibitors (RR 1.29, 95% CI 0.93 to 1.79, N = 827; 1 trial moclobemide, 5 selegiline), the atypical antidepressant venlafaxine (1 trial, N = 147, RR 1.22, 95% CI 0.64 to 2.32), the herbal therapy St John's wort (hypericum) (2 trials, N = 261, RR 0.81, 95% CI 0.26 to 2.53), or the dietary supplement SAMe (1 trial, N = 120, RR 0.70, 95% CI 0.24 to 2.07).

AUTHORS' CONCLUSIONS

The antidepressants bupropion and nortriptyline aid long-term smoking cessation. Adverse events with either medication appear to rarely be serious or lead to stopping medication. Evidence suggests that the mode of action of bupropion and nortriptyline is independent of their antidepressant effect and that they are of similar efficacy to nicotine replacement. Evidence also suggests that bupropion is less effective than varenicline, but further research is needed to confirm this finding. Evidence suggests that neither selective serotonin reuptake inhibitors (e.g. fluoxetine) nor monoamine oxidase inhibitors aid cessation.

Adapting smoking cessation treatment according to initial response to precessation nicotine patch

OBJECTIVE The authors evaluated an adaptive smoking cessation treatment strategy in which nicotine patch treatment was initiated before a quit date, and then, depending on initial therapeutic response, either the nicotine patch was continued or alternative pharmacotherapies were provided. METHOD The study was a double-blind, parallel-arm adaptive treatment trial. A total of 606 cigarette smokers started open-label nicotine patch treatment 2 weeks before the quit date. Those whose ad lib smoking did not decrease by &gt;50% after 1 week were randomly assigned to one of three double-blind treatments: nicotine patch alone (control condition); "rescue" treatment with bupropion augmentation of the patch; or rescue treatment with varenicline alone. Participants whose precessation smoking decreased &gt;50% but who lapsed after the quit date were also randomly assigned to the two rescue treatments or to nicotine patch alone. Logistic regression analyses compared each rescue treatment against the control condition in terms of abstinence at the end of treatment (weeks 8-11) and at 6 months. RESULTS Smokers who did not respond adequately to precessation nicotine patch benefited from bupropion augmentation; abstinence rates at end of treatment were 16% with nicotine patch alone and 28% with bupropion augmentation (odds ratio=2.04, 95% CI=1.03-4.01). Switching to varenicline produced less robust effects, but point abstinence at 6 months was 6.6% with the patch alone and 16.5% with a switch to varenicline (odds ratio=2.80, 95% CI=1.11-7.06). Postquit adaptive changes in treatment had no significant effects on any abstinence outcome. CONCLUSIONS It is possible to rescue a significant portion of smokers who would have failed to achieve abstinence if left on nicotine patch alone by identifying these smokers before their quit date and implementing adaptive changes in treatment.

Weight gain in smokers after quitting cigarettes: meta-analysis

OBJECTIVE

To describe weight gain and its variation in smokers who achieve prolonged abstinence for up to 12 months and who quit without treatment or use drugs to assist cessation.

DESIGN

Meta-analysis.

DATA SOURCES

We searched the Central Register of Controlled Trials (CENTRAL) and trials listed in Cochrane reviews of smoking cessation interventions (nicotine replacement therapy, nicotinic partial agonists, antidepressants, and exercise) for randomised trials of first line treatments (nicotine replacement therapy, bupropion, and varenicline) and exercise that reported weight change. We also searched CENTRAL for trials of interventions for weight gain after cessation.

REVIEW METHODS

Trials were included if they recorded weight change from baseline to follow-up in abstinent smokers. We used a random effects inverse variance model to calculate the mean and 95% confidence intervals and the mean of the standard deviation for weight change from baseline to one, two, three, six, and 12 months after quitting. We explored subgroup differences using random effects meta-regression.

RESULTS

62 studies were included. In untreated quitters, mean weight gain was 1.12 kg (95% confidence interval 0.76 to 1.47), 2.26 kg (1.98 to 2.54), 2.85 kg (2.42 to 3.28), 4.23 kg (3.69 to 4.77), and 4.67 kg (3.96 to 5.38) at one, two, three, six, and 12 months after quitting, respectively. Using the means and weighted standard deviations, we calculated that at 12 months after cessation, 16%, 37%, 34%, and 13% of untreated quitters lost weight, and gained less than 5 kg, gained 5-10 kg, and gained more than 10 kg, respectively. Estimates of weight gain were similar for people using different pharmacotherapies to support cessation. Estimates were also similar between people especially concerned about weight gain and those not concerned.

CONCLUSION

Smoking cessation is associated with a mean increase of 4-5 kg in body weight after 12 months of abstinence, and most weight gain occurs within three months of quitting. Variation in weight change is large, with about 16% of quitters losing weight and 13% gaining more than 10 kg.

Interventions for preventing weight gain after smoking cessation

BACKGROUND

Most people who stop smoking gain weight. There are some interventions that have been designed to reduce weight gain when stopping smoking. Some smoking cessation interventions may also limit weight gain although their effect on weight has not been reviewed.

OBJECTIVES

To systematically review the effect of: (1) Interventions targeting post-cessation weight gain on weight change and smoking cessation.(2) Interventions designed to aid smoking cessation that may also plausibly affect weight on post-cessation weight change.

SEARCH METHODS

Part 1 - We searched the Cochrane Tobacco Addiction Group's Specialized Register and CENTRAL in September 2011.Part 2 - In addition we searched the included studies in the following "parent" Cochrane reviews: nicotine replacement therapy (NRT), antidepressants, nicotine receptor partial agonists, cannabinoid type 1 receptor antagonists and exercise interventions for smoking cessation published in Issue 9, 2011 of the Cochrane Library.

SELECTION CRITERIA

Part 1 - We included trials of interventions that were targeted at post-cessation weight gain and had measured weight at any follow up point and/or smoking cessation six or more months after quit day.Part 2 - We included trials that had been included in the selected parent Cochrane reviews if they had reported weight gain at any time point.

DATA COLLECTION AND ANALYSIS

We extracted data on baseline characteristics of the study population, intervention, outcome and study quality. Change in weight was expressed as difference in weight change from baseline to follow up between trial arms and was reported in abstinent smokers only. Abstinence from smoking was expressed as a risk ratio (RR). We used the most rigorous definition of abstinence available in each trial. Where appropriate, we performed meta-analysis using the inverse variance method for weight and Mantel-Haenszel method for smoking using a fixed-effect model.

MAIN RESULTS

Part 1: Some pharmacological interventions tested for limiting post cessation weight gain (PCWG) resulted in a significant reduction in WG at the end of treatment (dexfenfluramine (Mean difference (MD) -2.50 kg, 95% confidence interval (CI) -2.98 to -2.02, 1 study), phenylpropanolamine (MD -0.50 kg, 95% CI -0.80 to -0.20, N=3), naltrexone (MD -0.78 kg, 95% CI -1.52 to -0.05, N=2). There was no evidence that treatment reduced weight at 6 or 12 months (m). No pharmacological intervention significantly affected smoking cessation rates.Weight management education only was associated with no reduction in PCWG at end of treatment (6 or 12m). However these interventions significantly reduced abstinence at 12m (Risk ratio (RR) 0.66, 95% CI 0.48 to 0.90, N=2). Personalised weight management support reduced PCWG at 12m (MD -2.58 kg, 95% CI -5.11 to -0.05, N=2) and was not associated with a significant reduction of abstinence at 12m (RR 0.74, 95% CI 0.39 to 1.43, N=2). A very low calorie diet (VLCD) significantly reduced PCWG at end of treatment (MD -3.70 kg, 95% CI -4.82 to -2.58, N=1), but not significantly so at 12m (MD -1.30 kg, 95% CI -3.49 to 0.89, N=1). The VLCD increased chances of abstinence at 12m (RR 1.73, 95% CI 1.10 to 2.73, N=1). There was no evidence that cognitive behavioural therapy to allay concern about weight gain (CBT) reduced PCWG, but there was some evidence of increased PCWG at 6m (MD 0.74, 95% CI 0.24 to 1.24). It was associated with improved abstinence at 6m (RR 1.83, 95% CI 1.07 to 3.13, N=2) but not at 12m (RR 1.25, 95% CI 0.83 to 1.86, N=2). However, there was significant statistical heterogeneity.Part 2: We found no evidence that exercise interventions significantly reduced PCWG at end of treatment (MD -0.25 kg, 95% CI -0.78 to 0.29, N=4) however a significant reduction was found at 12m (MD -2.07 kg, 95% CI -3.78 to -0.36, N=3).Both bupropion and fluoxetine limited PCWG at the end of treatment (bupropion MD -1.12 kg, 95% CI -1.47 to -0.77, N=7) (fluoxetine MD -0.99 kg, 95% CI -1.36 to -0.61, N=2). There was no evidence that the effect persisted at 6m (bupropion MD -0.58 kg, 95% CI -2.16 to 1.00, N=4), (fluoxetine MD -0.01 kg, 95% CI -1.11 to 1.10, N=2) or 12m (bupropion MD -0.38 kg, 95% CI -2.00 to 1.24, N=4). There were no data on WG at 12m for fluoxetine.Overall, treatment with NRT attenuated PCWG at the end of treatment (MD -0.69 kg, 95% CI -0.88 to -0.51, N=19), with no strong evidence that the effect differed for the different forms of NRT. There was evidence of significant statistical heterogeneity caused by one study which reported a 4.3 kg reduction in PCWG due to NRT. With this study removed, the difference in weight change at end of treatment was -0.45 kg (95% CI -0.66 to -0.27, N=18). There was no evidence of an effect on PCWG at 12m (MD -0.42 kg, 95% CI -0.92 to 0.08, N=15).We found evidence that varenicline significantly reduced PCWG at end of treatment (MD -0.41 kg, 95% CI -0.63 to -0.19, N=11), but this effect was not maintained at 6 or 12m. Three studies compared the effect of bupropion to varenicline. Participants taking bupropion gained significantly less weight at the end of treatment (-0.51 kg (95% CI -0.93 to -0.09 kg), N=3). Direct comparison showed no significant difference in PCWG between varenicline and NRT.

AUTHORS' CONCLUSIONS

Although some pharmacotherapies tested to limit PCWG show evidence of short-term success, other problems with them and the lack of data on long-term efficacy limits their use. Weight management education only, is not effective and may reduce abstinence. Personalised weight management support may be effective and not reduce abstinence, but there are too few data to be sure. One study showed a VLCD increased abstinence but did not prevent WG in the longer term. CBT to accept WG did not limit PCWG and may not promote abstinence in the long term. Exercise interventions significantly reduced weight in the long term, but not the short term. More studies are needed to clarify whether this is an effect of treatment or a chance finding. Bupropion, fluoxetine, NRT and varenicline reduce PCWG while using the medication. Although this effect was not maintained one year after stopping smoking, the evidence is insufficient to exclude a modest long-term effect. The data are not sufficient to make strong clinical recommendations for effective programmes to prevent weight gain after cessation.

Incremental efficacy of adding bupropion to the nicotine patch for smoking cessation in smokers with a recent history of alcohol dependence: results from a randomized, double-blind, placebo-controlled study

AIMS

The primary aim of this study was to compare the efficacy of smoking cessation treatment using a combination of nicotine patch and bupropion vs. nicotine patch and placebo bupropion. A secondary aim was to investigate whether the efficacy of bupropion is moderated by belief about whether one is receiving active or placebo medication.

METHODS

Participants were recruited from a residential substance abuse treatment program and the community. We randomly assigned 148 smokers with between 2 and 12 months of alcohol abstinence to nicotine patch plus bupropion or nicotine patch plus placebo. All participants also received seven counseling sessions.

RESULTS

At follow up, differences between medication conditions were not significant. Seven-day point prevalence quit rates in the patch plus bupropion vs. patch plus placebo conditions at week 24 were 6% and 11%, respectively. Differences between groups on prolonged abstinence and time to first smoking lapse were also not significant. However, among participants who received bupropion, those who accurately "guessed" that they were receiving bupropion were more likely to remain abstinent than those who incorrectly believed they were receiving placebo.

CONCLUSIONS

Findings do not support combining nicotine patch and bupropion for smoking cessation in this population. However, findings support previous studies suggesting the importance of assessing the blind in smoking cessation studies and its possible moderating effect on medication efficacy. Future directions for enhancing smoking cessation outcome in these smokers include investigations of intensive behavioral and pharmacological interventions, including studies of potential interactions between individual genetic differences and medication efficacy.

Effect of bupropion treatment on brain activation induced by cigarette-related cues in smokers

CONTEXT

Nicotine-dependent smokers exhibit craving and brain activation in the prefrontal and limbic regions when presented with cigarette-related cues. Bupropion hydrochloride treatment reduces cue-induced craving in cigarette smokers; however, the mechanism by which bupropion exerts this effect has not yet been described.

OBJECTIVE

To assess changes in regional brain activation in response to cigarette-related cues from before to after treatment with bupropion (vs placebo).

DESIGN

Randomized, double-blind, before-after controlled trial.

SETTING

Academic brain imaging center.

PARTICIPANTS

Thirty nicotine-dependent smokers (paid volunteers).

INTERVENTIONS

Participants were randomly assigned to receive 8 weeks of treatment with either bupropion or a matching placebo pill (double-blind).

MAIN OUTCOME MEASURES

Subjective cigarette craving ratings and regional brain activations (blood oxygen level-dependent response) in response to viewing cue videos.

RESULTS

Bupropion-treated participants reported less craving and exhibited reduced activation in the left ventral striatum, right medial orbitofrontal cortex, and bilateral anterior cingulate cortex from before to after treatment when actively resisting craving compared with placebo-treated participants. When resisting craving, reduction in self-reported craving correlated with reduced regional brain activation in the bilateral medial orbitofrontal and left anterior cingulate cortices in all participants.

CONCLUSIONS

Treatment with bupropion is associated with improved ability to resist cue-induced craving and a reduction in cue-induced activation of limbic and prefrontal brain regions, while a reduction in craving, regardless of treatment type, is associated with reduced activation in prefrontal brain regions.

Smoking-induced change in intrasynaptic dopamine concentration: effect of treatment for Tobacco Dependence

The aim of this study was to determine whether standard treatments for Tobacco Dependence affect smoking-induced changes in intrasynaptic dopamine (DA) concentration. Forty-three otherwise healthy adult cigarette smokers (10 to 40 cigarettes per day) were treated with either practical group counseling (PGC) psychotherapy (n=14), bupropion HCl (n=14), or matching pill placebo (n=15) (random assignment) for 8 weeks. Before and after treatment, each subject underwent a bolus-plus-continuous-infusion (11)C-raclopride positron emission tomography (PET) scanning session, during which he or she smoked a regular cigarette. The PET scanning outcome measure of interest was percent change in smoking-induced (11)C-raclopride binding potential (BP(ND)) in the ventral caudate/nucleus accumbens (VCD/NAc), as an indirect measure of DA release. Although the entire study sample had a smaller mean smoking-induced reduction in VCD/NAc BP(ND) after treatment (compared to before treatment), this change was highly correlated with smaller total cigarette puff volumes (and not other treatment variables). These data indicate that smoking-induced DA release is dose-dependent, and is not significantly affected by reductions in daily smoking levels or treatment type.

Do point prevalence and prolonged abstinence measures produce similar results in smoking cessation studies? A systematic review

INTRODUCTION

Many smoking cessation trials report either prolonged abstinence (PA) rates (i.e., not smoking since a quit date, with or without a grace period) or point prevalence (PP) abstinence rates (i.e., no smoking one or more days prior to the follow-up), but how these two relate is unclear.

METHODS

We located 28 pharmacotherapy trials that provided 76 within-study comparisons of PA versus PP. The first two authors independently coded all trials.

RESULTS

The two measures were highly correlated (r = .88) and PA averaged 0.74 that of PP. Equations for converting PP to PA and vice versa produced estimations that, in 90% of cases, were within 4%-5% of actual PP or PA values. The odds ratio and the relative risk for active versus control were identical when PA and PP were used; however, the difference in proportion abstinent for active versus control was somewhat less when PA was used than when PP was used (8% vs. 10%).

DISCUSSION

We conclude that PA and PP are closely related and can be interconverted with moderate accuracy. They also produce similar effect sizes when odds ratio and relative risk are used as effect sizes. When absolute difference in percent abstinent is used as an effect size, PA produces a smaller effect size than PP. We believe trials should continue to report both PA and PP outcomes to enhance comparisons across studies.

An open-label study of naltrexone and bupropion combination therapy for smoking cessation in overweight and obese subjects

A combination of sustained release (SR) naltrexone (32 mg/day) and bupropion SR (360 mg/day) plus behavioral counseling was evaluated for the treatment of smoking cessation and mitigation of nicotine withdrawal and weight gain. Thirty overweight or obese nicotine-dependent subjects were enrolled in a 24-week, open-label study; 85% and 63% completed 12 and 2 4weeks, respectively. The target quit date was Week 4. Week 4-12 continuous abstinence rate was 48%, 78% of subjects achieved CO < or = 10 ppm, serum cotinine decreased from 185 to 48 microg/L, and tobacco use decreased from 129 to 14 cigarettes/week. Similar results were seen at Week 24. Body weight was essentially unchanged (Week 12: -0.1%; Week 24: +0.4%). Except for a transient significant increase 1 week after the target quit date (p<0.05), nicotine withdrawal scores did not change. The most common adverse events were nausea, insomnia, and constipation. These tended to be transient and mild or moderate in severity. In overweight or obese smokers, naltrexone/bupropion combination therapy with behavioral counseling was associated with decreased nicotine use, limited nicotine withdrawal symptoms, and no significant weight gain.

Efficacy of pharmacotherapies for short-term smoking abstinance: a systematic review and meta-analysis

BACKGROUND

Smoking cessation has important immediate health benefits. The comparative short-term effectiveness of smoking cessation interventions is not well known. We aimed to determine the relative effectiveness of nicotine replacement therapy (NRT), bupropion and varenicline at 4 weeks post-target quit date.

METHODS

We searched 10 electronic medical databases (inception to October 2008). We selected randomized clinical trials [RCTs] evaluating interventions for our primary outcome of abstinence from smoking at at-least 4 weeks post-target quit date, with biochemical confirmation. We conducted random-effects odds ratio (OR) meta-analysis and meta-regression. We compared treatment effects across interventions using head-to-head trials and calculated indirect comparisons.

RESULTS

We combined a total of 101 trials evaluating delivery of NRT versus inert controls at approximately 4 weeks post-target quit date (total n = 31,321). The pooled overall OR is OR 2.05 (95% Confidence Interval [CI], 1.89-2.23, P =< 0.0001). We pooled data from 31 bupropion trials contributing a total n of 11,118 participants and found a pooled OR of 2.25 (95% CI, 1.94-2.62, P =< 0.0001). We evaluated 9 varenicline trials compared to placebo. Our pooled estimate for cessation at 4 weeks post-target quit date found a pooled OR of 3.16 (95% CI, 2.55-3.91, P =< 0.0001). Two trials evaluated head to head comparisons of varenicline and bupropion and found a pooled estimate of OR 1.86 (95% CI, 1.49-2.33, P =< 0.0001 at 4 weeks post-target quit date. Indirect comparisons were: NRT and bupropion, OR, 1.09, 95% CI, 0.93-1.31, P = 0.28; varenicline and NRT, OR 1.56, 95% CI, 1.23-1.96, P = 0.0002; and, varenicline and bupropion, OR 1.40, 95% CI, 1.08-1.85, P = 0.01.

CONCLUSION

Pharmacotherapeutic interventions are effective for increasing smoking abstinence rates in the short-term.

Beliefs and attitudes about bupropion: implications for medication adherence and smoking cessation treatment

Beliefs about medication are associated with treatment adherence and outcome. This is a secondary analysis of the role of beliefs and attitudes about bupropion in treatment adherence and smoking cessation outcomes using data from a smoking cessation trial of open-label sustained-release (SR) bupropion therapy reported previously (Toll et al., 2007). Positive beliefs and attitudes were positively correlated with intentions, desire, confidence, and motivation to quit smoking; expectation of quitting success; perceived benefits of quitting; and perceived disadvantages of smoking. Positive beliefs were also associated with greater medication adherence, an increased likelihood of completing treatment and being continuously abstinent, and a delayed latency to smoking lapse. These findings provide preliminary support that positive beliefs and attitudes about bupropion are associated with positive attitudes toward quitting, better treatment adherence, and potentially better treatment response.

Tobacco dependence and withdrawal: science base, challenges and opportunities for pharmacotherapy

Several pharmacotherapies for tobacco dependence and withdrawal have been approved by the Food and Drug Administration to aid smoking cessation. These medicines double to triple the odds of cessation compared to placebo, with the diversity in chemical entity (e.g., nicotine, varenicline, bupropion) and route (e.g., nicotine gum and transdermal patch) providing options for people who find a given medication unacceptable or ineffective. Treatments in development include vaccines, combinations of existing products, and new indications, such as reduced tobacco use and exposure. These therapies have been developed on the foundation of research on the neuropharmacology of tobacco dependence and withdrawal. Ongoing research is expected to contribute to more efficacious use of existing therapies and the development of new approaches. This article addresses these developments as well as the challenges to medication development. Challenges include understanding the population-based and individual differences in the vulnerability to dependence and responsiveness to various treatment options, which could contribute to effective treatment to patient matching. Research on the CNS effects of administration and withdrawal of nicotine and other tobacco product constituents is expanding, providing the basis for more effective therapeutic approaches and new medications development. Additionally, whereas medications are approved on the basis of standardized assessments of efficacy and safety in clinical trials, the public health impact of medications depends also on their appeal to smokers and their effectiveness in actual use settings. Research on more effective medication use along with policies that support improved access and utilization are vital to conquering the tobacco epidemic.

Sustained-release bupropion for hospital-based smoking cessation: a randomized trial

INTRODUCTION

Bupropion is a first-line pharmacological aid for smoking cessation; however, no clinical trials have been conducted in a general population of hospitalized smokers.

METHODS

We enrolled 85 smokers in a hospital-based randomized smoking cessation trial conducted at the San Francisco Veterans Affairs Medical Center. A total of 42 participants received a 7-week course of sustained-release bupropion and 43 participants received placebo. All participants received cognitive-behavioral counseling. We screened 14,997 patients, of whom 25% were current smokers. Of the 536 smokers who met the entry criteria, 451 opted not to enroll. We determined on-medication, end-of-medication, 3-month, and 6-month smoking cessation rates.

RESULTS

At the end of 7 weeks of drug treatment, self-reported quit rates were equivalent in the bupropion and placebo arms, 37% versus 33%, respectively (p = .82). The validated quit rates for the bupropion and placebo groups were 27% versus 29%, respectively (p = 1.00). At 6 months, the self-reported quit rates were 29% in the bupropion group and 41% in the placebo group (p = .36). In a comparison of 6-month quit rates, validated either by salivary cotinine or by spousal proxy, we found nonsignificantly higher quit rates in the placebo group than in the bupropion group, 31% versus 15% (p = .12).

DISCUSSION

The addition of sustained-release bupropion to counseling did not increase quit rates, but the study was underpowered. Because of the secular trend toward shorter hospital stays, recruitment was very difficult, raising questions regarding the feasibility of future hospital-based smoking cessation trials and interventions.

Macrovascular Complications of Diabetes Mellitus

Adults with diabetes mellitus frequently develop macrovascular complications. Vascular disease is a frequent cause of morbidity and mortality among patients with diabetes. Diabetes and vascular diseases remain among the most common causes of death in the United States. A number of clinical trials and practice guidelines have been published addressing the management of macrovascular complications. The cornerstone of preventing or delaying the progression of macrovascular complications of diabetes is aggressive management of hypertension and cholesterol. Angiotensin-converting enzyme inhibitors have proven effective in managing hypertension and avoiding other complications of diabetes. The body of evidence for angiotensin receptor blockers is growing in this area as well. Statins have been repeatedly proven to be the first-line agents in the management of dyslipidemia. Lifestyle modification strategies and antiplatelet therapy also remain essential. This review will focus on the role of newer diagnostic techniques, clinical trial evidence, and appropriate pharmacotherapy for macrovascular complications of diabetes.

Interventions for preventing weight gain after smoking cessation

BACKGROUND

Most people who stop smoking gain weight, on average about 7 kg in the long term. There are some interventions that have been specifically designed to tackle smoking cessation whilst also limiting weight gain. Many smoking cessation pharmacotherapies and other interventions may also limit weight gain.

OBJECTIVES

This review is divided into two parts. (1) Interventions designed specifically to aid smoking cessation and limit post-cessation weight gain (2) Interventions designed to aid smoking cessation that may also plausibly have an effect on weight

SEARCH STRATEGY

Part 1: We searched the Cochrane Tobacco Addiction Group's Specialized Register which includes trials indexed in MEDLINE, EMBASE, SciSearch and PsycINFO, and other reviews and conference abstracts. Part 2: We searched the included studies of Cochrane smoking cessation reviews of nicotine replacement therapy, antidepressants, nicotine receptor partial agonists, cannabinoid type 1 receptor antagonists (rimonabant), and exercise interventions, published in Issue 4, 2008 of The Cochrane Library.

SELECTION CRITERIA

Part 1: We included trials of interventions designed specifically to address both smoking cessation and post-cessation weight gain that had measured weight at any follow-up point and/or smoking six months or more after quitting.Part 2: We included trials from the selected Cochrane reviews that could plausibly modify post-cessation weight gain if they had reported weight gain by trial arm at end of treatment or later.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate on smoking and weight for part 1 trials, and on weight only for part 2. Abstinence from smoking is expressed as a risk ratio (RR), using the most rigorous definition of abstinence available in each trial, and biochemically validated rates if available. The outcome is expressed as the difference in weight change between trial arms from baseline. Where appropriate, we performed meta-analysis using the Mantel-Haenszel method for smoking and inverse variance for weight using a fixed-effect model.

MAIN RESULTS

We found evidence that pharmacological interventions aimed at reducing post-cessation weight gain resulted in a significant reduction in weight gain at the end of treatment (dexfenfluramine (-2.50kg [-2.98kg to -2.02kg], fluoxetine (-0.80kg [-1.27kg to -0.33kg], phenylpropanolamine (PPA) (-0.50kg [-0.80kg to -0.20kg], naltrexone (-0.76kg [-1.51kg to -0.01kg])). No evidence of maintenance of the treatment effect was found at six or 12 months.Among the behavioural interventions, only weight control advice was associated with no reduction in weight gain and with a possible reduction in abstinence. Individualized programmes were associated with reduced weight gain at end of treatment and at 12 months (-2.58kg [-5.11kg to -0.05kg]), and with no effect on abstinence (RR 0.74 [0.39 to 1.43]). Very low calorie diets (-1.30kg (-3.49kg to 0.89kg] at 12 months) and cognitive behavioural therapy (CBT) (-5.20kg (-9.28kg to -1.12kg] at 12 months) were both associated with improved abstinence and reduced weight gain at end of treatment and at long-term follow up.Both bupropion (300mg/day) and fluoxetine (30mg and 60mg/day combined) were found to limit post-cessation weight gain at the end of treatment (-0.76kg [-1.17kg to -0.35kg] I(2)=48%) and -1.30kg [-1.91kg to -0.69kg]) respectively. There was no evidence that the weight reducing effect of bupropion was dose-dependent. The effect of bupropion at one year was smaller and confidence intervals included no effect (-0.38kg [-2.001kg to 1.24kg]).We found no evidence that exercise interventions significantly reduced post-cessation weight gain at end of treatment but evidence for an effect at 12 months (-2.07kg [-3.78kg, -0.36kg]).Treatment with NRT resulted in attenuation of post-cessation weight gain (-0.45kg [-0.70kg, -0.20kg]) at the end of treatment, with no evidence that the effect differed for different forms of NRT. The estimated weight gain reduction was similar at 12 months (-0.42kg [-0.92kg, 0.08kg]) but the confidence intervals included no effect.There were no relevant data on the effect of rimonabant on weight gain.We found no evidence that varenicline significantly reduced post-cessation weight gain at end of treatment and no follow-up data are currently available. One study randomizing successful quitters to 12 more weeks of active treatment showed weight to be reduced by 0.71kg (-1.04kg to -0.38kg). In three studies, participants taking bupropion gained significantly less weight at the end of treatment than those on varenicline (-0.51kg [-0.93kg to -0.09kg]).

AUTHORS' CONCLUSIONS

Behavioural interventions of general advice only are not effective and may reduce abstinence. Individualized interventions, very low calorie diets, and CBT may be effective and not reduce abstinence. Exercise interventions are not associated with reduced weight gain at end of treatment, but may be associated with worthwhile reductions in weight gain in the long term, Bupropion, fluoxetine, nicotine replacement therapy, and probably varenicline all reduced weight gain while being used. Although this effect was not maintained one year after quitting for bupropion, fluoxetine, and nicotine replacement, the evidence is insufficient to exclude a modest long-term effect. The data are not sufficient to make strong clinical recommendations for effective programmes.

Risk factors for treatment failure in smokers: relationship to alcohol use and to lifetime history of an alcohol use disorder

Little is known about the impact of alcohol involvement on smoking cessation relapse or possible mechanisms for these associations. We addressed these issues using data from a randomized clinical trial of two types of framed messages (gain vs. loss) in conjunction with open label sustained-release (SR) bupropion (Toll et al., 2007) (N = 249). Participants were categorized according to whether or not they were diagnosed with a lifetime alcohol use disorder (AUD; i.e., current or past alcohol abuse or past alcohol dependence) and according to three levels of alcohol use: abstinence, moderate, or hazardous use. Alcohol use categories were established for drinking at baseline, during the 6-week treatment period and through 12 weeks post-quit. There were few significant differences by baseline alcohol use level or AUD history for a series of predictors of smoking cessation failure (e.g., depressive symptoms). During treatment and follow-up, the probability of any smoking on heavy drinking days was significantly higher than the probability of smoking on moderate drinking or abstinent days. AUD history did not predict smoking cessation relapse in any analysis, nor were any alcohol usexAUD history interactions significant. Moderate alcohol users and, to a lesser extent, abstainers from alcohol at baseline were less likely than hazardous drinkers to have relapsed at 12 weeks post-quit. Based on these findings, it appears that risk of any smoking and of relapse was associated primarily with heavy drinking days and a hazardous pattern of use respectively, rather than with moderate drinking.

The impact of perceived treatment assignment on smoking cessation outcomes among African-American smokers

BACKGROUND

The double-blind placebo-controlled design is commonly considered the gold standard in research methodology; however, subject expectation bias could subvert blinding.

OBJECTIVE

The primary aim of this study was to examine the impact of expectation bias. Specifically, we examined perceived treatment assignment on smoking cessation outcome rates among participants enrolled in a clinical trial of bupropion (150 mg SR, BID).

DESIGN

Analyses were conducted on data collected during "Kick It at Swope," a double-blind, placebo-controlled, randomized trial of 600 African-American smokers. Chi-square and multiple logistic regression analyses were used to examine the impact of perception of assignment on treatment effect and cotinine-verified smoking abstinence rates.

PARTICIPANTS

Participants were predominantly middle-aged (mean 44.7, SD 11.2), African-American women (68.6%), who smoked 19 CPD (SD = 8.1). Most had completed at least a high school education or GED (51.6%), and 55% had a monthly family income <$1,800.

MEASUREMENTS

At week 6 (end of treatment) and week 26 (end of study), participants were asked to report their perceived treatment group assignment. Self-reported abstinence (weeks 6 and 26) was confirmed using CO and cotinine biochemical verification.

RESULTS

After adjusting for actual treatment assignment, age and baseline cotinine, participants who perceived being assigned to bupropion vs. placebo were more likely to be abstinent at weeks 6 (OR = 2.07, 95% CI: 1.29 to 3.33, p = 0.002) and 26 (OR = 1.85, 95% CI: 1.05 to 3.24, p = 0.032).

CONCLUSIONS

Results support previous research that expectation bias associated with judgment of treatment assignment is a strong predictor of outcome and confirms this relationship in a smoking cessation trial using bupropion SR among African-American smokers.

Influence of Neuronal Nicotinic Receptors over Nicotine Addiction and Withdrawal

Cigarette smoking represents an enormous, global public health threat. Nearly five million premature deaths during a single year are attributable to smoking. Despite the resounding message of risks associated with smoking and numerous public health initiatives, cigarette smoking remains the most common preventable cause of disease in the United States. Fortunately, even in an adult smoker, smoking cessation can reverse many of the potential harmful effects. The symptoms associated with nicotine withdrawal represent the major obstacle to smoking cessation. This minireview examines the roles of various nicotinic receptors in the mechanisms of nicotine dependence, discusses the potential role of the habenula-interpeduncular nucleus axis in nicotine withdrawal, and highlights nicotinic receptors containing the β4 subunit as a potential pharmacological target for smoking cessation strategies.

Tobacco addiction

Tobacco use is associated with 5 million deaths per year worldwide and is regarded as one of the leading causes of premature death. Comprehensive programmes for tobacco control can substantially reduce the frequency of tobacco use. An important component of a comprehensive programme is the provision of treatment for tobacco addiction. Treatment involves targeting several aspects of addiction including the underlying neurobiology and behavioural processes. Furthermore, building an infrastructure in health systems that encourages and helps with cessation, as well as expansion of the accessibility of treatments, is necessary. Although pharmacological and behavioural treatments are effective in improving cessation success, the rate of relapse to smoking remains high, emphasising the strong addictive nature of nicotine. The future of treatment resides in improvement in patient matching to treatment, combination or novel drugs, and viewing nicotine addiction as a chronic disorder that might need long-term treatment.

Which is the best primary medication for long-term smoking cessation--nicotine replacement therapy, bupropion or varenicline?

Nicotine chewing gum has been available since 1982, when it was shown to increase smoking cessation rates by approximately 1.5- to 2-fold after 12 months. Despite the introduction of many other preparations of nicotine (sublingual, lozenge, transdermal, nasal spray and inhaler) and numerous other clinical trials, there has been no major improvement in effectiveness for smoking cessation, just an increase in the choice of how the nicotine replacement therapy (NRT) is administered. Smoking cessation rates with NRT are similar in subjects with serious chest and cardiovascular disorders. There is no evidence that intensive counselling improves the smoking cessation rates with NRT over standard counselling. The first major alternative to NRT introduced for smoking cessation was bupropion, an inhibitor of the neuronal uptake of noradrenaline and dopamine. Bupropion is effective for smoking cessation, and effectiveness is improved by a moderate level of counselling. A long-term direct comparison of bupropion with transdermal nicotine showed than bupropion was more effective than nicotine. Despite this, NRT remains the standard treatment for smoking cessation in many countries. An exciting new development for the treatment of smoking cessation is varenicline, a partial agonist at nicotinic alpha4beta2 receptors. A direct comparison of varenicline with bupropion has shown that varenicline is as least as good as and probably more effective than bupropion for smoking cessation. At present, the number of subjects who have used varenicline in clinical trial is relatively small, and probably does not allow assessment of any rare serious adverse effects. Thus, it may be premature to recommend varenicline for smoking cessation in preference to bupropion.

Cost effectiveness analysis of smoking cessation interventions

OBJECTIVE

To identify which smoking cessation interventions provide the most efficient use of health care resources at a population level.

METHODS

Effectiveness data were obtained from a review of the international literature. Costs and effects of smoking cessation interventions were estimated from the perspective of the Australian Government. Treatment costs and effects were modelled using incremental cost-effectiveness ratios. Assumptions regarding effectiveness, resource use and costs were tested by sensitivity analysis.

RESULTS

From the population perspective, telephone counselling appeared to be the most cost-effective intervention. Adding proactive forms of telephone counselling increased the effectiveness of pharmacotherapies at a low incremental cost and, therefore, this could be a highly cost-effective strategy. Bupropion appeared to be more cost effective than nicotine replacement therapy (NRT). Combined bupropion and NRT did not appear to be cost effective.

CONCLUSIONS

General practitioners should be encouraged to refer patients to telephone quit lines and if prescribing pharmacotherapy consider the addition of telephone counselling.

IMPLICATIONS

The results support greater investment in proactive forms of telephone counselling and more formal integration of pharmacotherapies with proactive telephone counselling services as cost-effective strategies for reducing population-level smoking rates.

Bupropion and cognitive-behavioral treatment for depression in smoking cessation

This study is a randomized, double-blind, placebo-controlled clinical trial examining the effects of an intensive cognitive-behavioral mood management treatment (CBTD) and of bupropion, both singularly and in combination, on smoking cessation in adult smokers. As an extension of our previous work, we planned to examine the synergistic effects of CBTD and bupropion on smoking cessation outcomes in general and among smokers with depression vulnerability factors. Participants were 524 smokers (47.5% female, M (age) = 44.27 years) who were randomized to one of four 12-week treatments: (a) standard, cognitive-behavioral smoking cessation treatment (ST) plus bupropion (BUP), (b) ST plus placebo (PLAC), (c) standard cessation treatment combined with cognitive-behavioral treatment for depression (CBTD) plus BUP, and (d) CBTD plus PLAC. Follow-up assessments were conducted 2, 6, and 12 months after treatment, and self-reported abstinence was verified biochemically. Consistent with previous studies, bupropion, in comparison with placebo, resulted in better smoking outcomes in both intensive group treatments. Adding CBTD to standard intensive group treatment did not result in improved smoking cessation outcomes. In addition, neither CBTD nor bupropion, either alone or in combination, was differentially effective for smokers with single-past-episode major depressive disorder (MDD), recurrent MDD, or elevated depressive symptoms. However, findings with regard to recurrent MDD and elevated depressive symptoms should be interpreted with caution given the low rate of recurrent MDD and the low level of depressive symptoms in our sample. An a priori test of treatment effects in smokers with these depression vulnerability factors is warranted in future clinical trials.

Can the blind see? Participant guess about treatment arm assignment may influence outcome in a clinical trial of bupropion for smoking cessation

In a placebo-controlled bupropion smoking cessation trial, we examined blind integrity, the link between blind integrity and quit rates, and whether side effects and changes in nicotine withdrawal symptoms or mood were mechanisms through which blind integrity is threatened. At a 12-month follow-up, 498 participants indicated whether they thought they received bupropion, placebo, or were not sure. Potential mediators of treatment effects on treatment arm guess (i.e., side effects, withdrawal, and mood) were measured during treatment, and 7-day point prevalence cessation was assessed at the end of treatment (EOT) and at 6 and 12 months after quit date. Overall, 55% of participants guessed their randomization correctly. Compared to guessing not sure, participants who guessed they were taking bupropion were more than twice as likely to have been randomized to bupropion. Similarly, participants who guessed placebo were twice as likely to have been randomized to placebo. Treatment arm guess was associated with quit rates. Including treatment arm guess with actual treatment arm in models of quit rates significantly reduced the odds ratio for bupropion efficacy at the EOT and at 6 and 12 months after quit date. There was no evidence for mediation. In bupropion smoking cessation trials, blind failure may occur and participant guess about treatment arm assignment is associated with quit rates.

Pharmacological approaches to smoking cessation

Smoking, the most prominent nongenetic factor contributing to mortality, remains the major public health problem throughout the world. There are nearly 1.1 billion users of nicotine and tobacco products worldwide while approximately one third to half of them will die from smoking-related disease. The habit of smoking is mainly propelled by nicotine, a strongly addictive substance, to which the vast majority of smokers fall victim. Except for the general and specific support and counseling strategies there are now effective treatments for nicotine addiction. Two types of pharmacological therapies have been approved and are now licensed for smoking cessation. The first therapy consists of nicotine replacement, substituting the nicotine from cigarettes with safer nicotine formulations. The second therapy is bupropion, an antidepressant of the aminoketone class, which has been demonstrated to be effective in smoking cessation. However, although some cigarette smokers are able to quit, many are not, and standard medications to assist smoking cessation are ineffective. Several agents used for other indications (e.g. neurological diseases, depression, alcoholism) might be used to treat this subgroup. In conclusion, new more effective drugs are needed in order to fight the panepidemic of smoking globally.

Alcohol history and smoking cessation in nicotine replacement therapy, bupropion sustained release and varenicline trials: a review

AIMS

We conducted a review of published reports of smoking cessation pharmacotherapy trials in order to address the following: (i) the generalizability of findings to smokers with a history of alcohol problems; (ii) the extent to which alcohol use affects smoking cessation overall and the efficacy of pharmacotherapy specifically and (iii) the effect of smoking cessation on alcohol use.

METHODS

We located published reports of nicotine replacement therapy (NRT), bupropion sustained release (SR) and varenicline clinical trials using an approach based on prior Cochrane reviews. The reports were searched for alcohol-related inclusion/exclusion criteria and for findings related to alcohol.

RESULTS

The present review included 212 published reports from 149 trials. Alcohol-related exclusion criteria appeared frequently (41.6% of trials)--45/125 NRT trials (36%), 15/22 bupropion SR trials (68.2%) and 3/3 varenicline trials--and most commonly involved exclusion of participants with either current or recent alcohol problems. Most studies failed to provide any baseline alcohol-related characteristics. Eleven trials reported on the relationship between alcohol history and likelihood of smoking cessation. In the majority of these studies, smokers with a past history of alcohol problems were not at a disadvantage, although contrary findings exist. Only two studies examined the potential influence of smoking cessation on alcohol use.

CONCLUSIONS

Smokers with alcohol problems, particularly those with current or recent problems, are underrepresented in studies of approved pharmacotherapy for smoking cessation. Future trials should assess alcohol use at baseline and during treatment and examine reciprocal influences between alcohol consumption and smoking cessation.

Non-Nicotinic Therapies for Smoking Cessation

Cigarette smoking is the primary cause of numerous preventable diseases; as such, the goals of smoking cessation are both to reduce health risks and to improve the quality of life. Currently, the first-line smoking cessation therapies include nicotine replacement products and bupropion. The nicotinic receptor partial agonist varenicline has recently been approved by the FDA for smoking cessation. A newer product currently under development and seeking approval by the FDA are nicotine vaccines. Clonidine and nortriptyline have demonstrated some efficacy but side effects may limit their use to second-line therapeutic products. Other therapeutic drugs that are under development include rimonabant, mecamylamine, monoamine oxidase inhibitors, and dopamine receptor D3 antagonists. Inhibitors of nicotine metabolism are also promising candidates for smoking reduction and cessation. In conclusion, promising new therapeutic products are emerging and they will provide smokers additional options to assist in achieving smoking cessation.

Antidepressants for smoking cessation

BACKGROUND

There are at least two theoretical reasons to believe antidepressants might help in smoking cessation. Nicotine withdrawal may produce depressive symptoms or precipitate a major depressive episode and antidepressants may relieve these. Nicotine may have antidepressant effects that maintain smoking, and antidepressants may substitute for this effect. Alternatively, some antidepressants may have a specific effect on neural pathways underlying nicotine addiction, (e.g. blocking nicotine receptors) independent of their antidepressant effects.

OBJECTIVES

The aim of this review is to assess the effect of antidepressant medications in aiding long-term smoking cessation. The medications include bupropion; doxepin; fluoxetine; imipramine; moclobemide; nortriptyline; paroxetine; sertraline, tryptophan and venlafaxine.

SEARCH STRATEGY

We searched the Cochrane Tobacco Addiction Group trials register which includes trials indexed in MEDLINE, EMBASE, SciSearch and PsycINFO, and other reviews and meeting abstracts, in September 2006.

SELECTION CRITERIA

We considered randomized trials comparing antidepressant medications to placebo or an alternative pharmacotherapy for smoking cessation. We also included trials comparing different doses, using pharmacotherapy to prevent relapse or re-initiate smoking cessation or to help smokers reduce cigarette consumption. We excluded trials with less than six months follow up.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate on the type of study population, the nature of the pharmacotherapy, the outcome measures, method of randomization, and completeness of follow up. The main outcome measure was abstinence from smoking after at least six months follow up in patients smoking at baseline, expressed as an odds ratio (OR). We used the most rigorous definition of abstinence available in each trial, and biochemically validated rates if available. Where appropriate, we performed meta-analysis using a fixed-effect model.

MAIN RESULTS

Seventeen new trials were identified since the last update in 2004 bringing the total number of included trials to 53. There were 40 trials of bupropion and eight trials of nortriptyline. When used as the sole pharmacotherapy, bupropion (31 trials, odds ratio [OR] 1.94, 95% confidence interval [CI] 1.72 to 2.19) and nortriptyline (four trials, OR 2.34, 95% CI 1.61 to 3.41) both doubled the odds of cessation. There is insufficient evidence that adding bupropion or nortriptyline to nicotine replacement therapy provides an additional long-term benefit. Three trials of extended therapy with bupropion to prevent relapse after initial cessation did not find evidence of a significant long-term benefit. From the available data bupropion and nortriptyline appear to be equally effective and of similar efficacy to nicotine replacement therapy. Pooling three trials comparing bupropion to varenicline showed a lower odds of quitting with bupropion (OR 0.60, 95% CI 0.46 to 0.78). There is a risk of about 1 in 1000 of seizures associated with bupropion use. Concerns that bupropion may increase suicide risk are currently unproven. Nortriptyline has the potential for serious side-effects, but none have been seen in the few small trials for smoking cessation. There were six trials of selective serotonin reuptake inhibitors; four of fluoxetine, one of sertraline and one of paroxetine. None of these detected significant long-term effects, and there was no evidence of a significant benefit when results were pooled. There was one trial of the monoamine oxidase inhibitor moclobemide, and one of the atypical antidepressant venlafaxine. Neither of these detected a significant long-term benefit.

AUTHORS' CONCLUSIONS

The antidepressants bupropion and nortriptyline aid long-term smoking cessation but selective serotonin reuptake inhibitors (e.g. fluoxetine) do not. Evidence suggests that the mode of action of bupropion and nortriptyline is independent of their antidepressant effect and that they are of similar efficacy to nicotine replacement. Adverse events with both medications are rarely serious or lead to stopping medication.

Effectiveness of smoking cessation therapies: a systematic review and meta-analysis

Background

Smoking remains the leading preventable cause of premature deaths. Several pharmacological interventions now exist to aid smokers in cessation. These include Nicotine Replacement Therapy [NRT], bupropion, and varenicline. We aimed to assess their relative efficacy in smoking cessation by conducting a systematic review and meta-analysis.

Methods

We searched 10 electronic medical databases (inception to Sept. 2006) and bibliographies of published reviews. We selected randomized controlled trials [RCTs] evaluating interventions for smoking cessation at 1 year, through chemical confirmation. Our primary endpoint was smoking cessation at 1 year. Secondary endpoints included short-term smoking cessation (~3 months) and adverse events. We conducted random-effects meta-analysis and meta-regression. We compared treatment effects across interventions using head-to-head trials and when these did not exist, we calculated indirect comparisons.

Results

We identified 70 trials of NRT versus control at 1 year, Odds Ratio [OR] 1.71, 95% Confidence Interval [CI], 1.55–1.88, P =< 0.0001). This was consistent when examining all placebo-controlled trials (49 RCTs, OR 1.78, 95% CI, 1.60–1.99), NRT gum (OR 1.60, 95% CI, 1.37–1.86) or patch (OR 1.63, 95% CI, 1.41–1.89). NRT also reduced smoking at 3 months (OR 1.98, 95% CI, 1.77–2.21). Bupropion trials were superior to controls at 1 year (12 RCTs, OR1.56, 95% CI, 1.10–2.21, P = 0.01) and at 3 months (OR 2.13, 95% CI, 1.72–2.64). Two RCTs evaluated the superiority of bupropion versus NRT at 1 year (OR 1.14, 95% CI, 0.20–6.42).

Varenicline was superior to placebo at 1 year (4 RCTs, OR 2.96, 95% CI, 2.12–4.12, P =< 0.0001) and also at approximately 3 months (OR 3.75, 95% CI, 2.65–5.30). Three RCTs evaluated the effectiveness of varenicline versus bupropion at 1 year (OR 1.58, 95% CI, 1.22–2.05) and at approximately 3 months (OR 1.61, 95% CI, 1.16–2.21). Using indirect comparisons, varenicline was superior to NRT when compared to placebo controls (OR 1.66, 95% CI 1.17–2.36, P = 0.004) or to all controls at 1 year (OR 1.73, 95% CI 1.22–2.45, P = 0.001). This was also the case for 3-month data. Adverse events were not systematically different across studies.

Conclusion

NRT, bupropion and varenicline all provide therapeutic effects in assisting with smoking cessation. Direct and indirect comparisons identify a hierarchy of effectiveness.

Smoking cessation and depression: current knowledge and future directions

This paper reviews the literature on comorbid smoking and depression. Current models used to explain this co-occurrence are examined, as are treatment options (both psychological and pharmacological). This paper surmises that treatment planning should consider factors that potentially confound treatment efficacy, including the nature of the depressive illness and the patient's smoking profile. Although there is limited research examining the benefits of a stepped-care framework, a tiered treatment format appears to work well, assisting those who require minimal treatment, as well as those who prolonged difficulties. Further research examining a stepped-care framework for smokers at risk of depression is required, as is appropriate training for health practitioners using this model. Further directions for research and practice are also discussed.

Bupropion for the treatment of nicotine withdrawal and craving

Over the past decade, bupropion has become a major pharmacotherapy for smoking cessation in the Western world. Unlike other smoking cessation pharmacotherapies, bupropion is a non-nicotine treatment. Compared with a placebo control, bupropion approximately doubles smoking quit rates. Most smoking cessation pharmacotherapies are thought to work, in part, by reducing nicotine withdrawal and craving. This article reviews preclinical, human laboratory and clinical trial studies of the effect of bupropion on nicotine withdrawal and craving. Preclinical studies demonstrate that in rats undergoing nicotine withdrawal, bupropion can dose-dependently lower changes in brain-reward threshold and somatic signs of nicotine withdrawal. Human laboratory studies have demonstrated that bupropion can alleviate some nicotine withdrawal symptoms, including depressed mood, irritability, difficulty concentrating and increased appetite. Moreover, bupropion has shown some efficacy in alleviating craving to smoke. Clinical trials of bupropion have offered mixed support of its ability to reduce nicotine withdrawal, weight gain during treatment and craving. Strong mediational evidence of bupropion's action through relief of withdrawal and craving in smoking cessation is growing. Greater understanding of the psychological mechanisms of bupropion action will likely be obtained through advances in the conceptualization and measurement of withdrawal and craving. Improvements in the efficacy of bupropion may be achieved through pharmacogenetic studies, with particular emphasis on its metabolites. Ultimately, the efficacy of bupropion may be augmented by combination with other agents that target withdrawal and craving through complementary neurobiological processes.

Pharmacologic interventions for smoking cessation

According to the US Public Health Service, all patients attempting to quit smoking should be encouraged to use one or more effective pharmacotherapy agents for cessation except in the presence of special circumstances. This article provides an overview of the pharmacologic agents for acute and critical care nurses to consider when intervening with tobacco-dependent patients. Medications addressed in this article include (1) first-line agents (nicotine replacement therapy, sustained-release bupropion) that have proven efficacy and are approved by the Food and Drug Administration (FDA) for smoking cessation, (2) second-line agents (nortriptyline, clonidine) that have proven efficacy but no FDA indication for smoking cessation, (3) approaches that use of combination or high-dose therapy, (4) herbal therapies, and (5) emerging therapies that are currently under investigation.

Pharmacotherapy and smoking cessation at a tobacco dependence clinic

BACKGROUND

Tobacco dependence medications are effective, and combinations may offer advantages. This study evaluates abstinence rates among smokers treated in a tobacco specialist clinic with individual and/or group counseling plus combination pharmacotherapy.

METHODS

790 smokers treated at the Tobacco Dependence Clinic in New Jersey from 2001-2003 and contacted 4 weeks after quit-date were studied. Patients received medications and behavioral interventions. Abstinence over the previous 7 days was evaluated at 4 weeks and 6 months. Patients lost to 6-month follow-up were considered still smoking.

RESULTS

Overall, 36% of patients were abstinent at 6 months (20% who used no medications, 37% using one medication, 37% using 2 medications, 42% using 3 medications, and 42% using 4+ medications) (P = 0.017). 27% still used medications at 6 months, and had higher abstinence rates (65%) than those who stopped their medications (27%) (P < 0.001). Number of medications predicted abstinence at 4 weeks [adjusted odds ratios = 2.30 (95% CI; 1.27-4.18) for 1 medication, 4.78 (2.72-8.40) for 2 medications, 5.83 (2.98-11.40) for 3 medications, and 11.80 (4.10-33.95) for 4+ medications]. Increasing age, increasing level of education, longer time after waking to first cigarette, more than 7 clinical contacts, and more medications used were related to higher abstinence at 6 months.

CONCLUSIONS

Smokers attending a specialist tobacco dependence treatment clinic who used more medications and for longer duration had higher abstinence rates.

How does bupropion work as a smoking cessation aid?

Bupropion exhibits reasonable efficacy as a smoking cessation aid, yet its precise mechanisms of action remain unclear. This review evaluates the mechanism of action of bupropion by considering the clinical evidence in combination with results from pre-clinical experiments in vivo and in vitro. Bupropion is a weak inhibitor of dopamine and noradrenaline reuptake, and has also been shown to antagonise nicotinic acetylcholine receptor function. It is extensively metabolized in humans, its major metabolites reaching levels higher than those of bupropion itself. These metabolites share many of the pharmacological properties of bupropion, so they may play an important role in its clinical activity, yet they have been neglected in investigations into bupropion action. This review led to several conclusions: (1) the principal mode of bupropion action is upon the withdrawal symptoms following smoking cessation; (2) during withdrawal, bupropion may attenuate symptoms by mimicking nicotinic effects on dopamine and noradrenaline; (3) its ability to antagonize nicotinic receptors may prevent relapse by attenuating the reinforcing properties of nicotine, but probably cannot acutely reduce smoking; and (4) further exploration of bupropion metabolites and its role in withdrawal and relapse, within more appropriate animal models, could be crucial in the determination of the precise mechanisms by which bupropion exerts its activity in smoking cessation. Greater elucidation of the exact mechanisms of action of bupropion could lead to the development of new drugs even more beneficial in promoting smoking abstinence.