Nicotine patch therapy based on smoking rate followed by bupropion for prevention of relapse to smoking

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.

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.

Relapse prevention interventions for smoking cessation

BACKGROUND

A number of treatments can help smokers make a successful quit attempt, but many initially successful quitters relapse over time. Several interventions have been proposed to help prevent relapse.

OBJECTIVES

To assess whether specific interventions for relapse prevention reduce the proportion of recent quitters who return to smoking.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group trials register, clinicaltrials.gov, and the ICTRP in May 2019 for studies mentioning relapse prevention or maintenance in their title, abstracts, or keywords.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of relapse prevention interventions with a minimum follow-up of six months. We included smokers who quit on their own, were undergoing enforced abstinence, or were participating in treatment programmes. We included studies that compared relapse prevention interventions with a no intervention control, or that compared a cessation programme with additional relapse prevention components with a cessation programme alone.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 81 studies (69,094 participants), five of which are new to this update. We judged 22 studies to be at high risk of bias, 53 to be at unclear risk of bias, and six studies to be at low risk of bias. Fifty studies included abstainers, and 30 studies helped people to quit and then tested treatments to prevent relapse. Twenty-eight studies focused on special populations who were abstinent because of pregnancy (19 studies), hospital admission (six studies), or military service (three studies). Most studies used behavioural interventions that tried to teach people skills to cope with the urge to smoke, or followed up with additional support. Some studies tested extended pharmacotherapy. We focused on results from those studies that randomised abstainers, as these are the best test of relapse prevention interventions. Of the 12 analyses we conducted in abstainers, three pharmacotherapy analyses showed benefits of the intervention: extended varenicline in assisted abstainers (2 studies, n = 1297, risk ratio (RR) 1.23, 95% confidence interval (CI) 1.08 to 1.41, I² = 82%; moderate-certainty evidence), rimonabant in assisted abstainers (1 study, RR 1.29, 95% CI 1.08 to 1.55), and nicotine replacement therapy (NRT) in unaided abstainers (2 studies, n = 2261, RR 1.24, 95% Cl 1.04 to 1.47, I² = 56%). The remainder of analyses of pharmacotherapies in abstainers had wide confidence intervals consistent with both no effect and a statistically significant effect in favour of the intervention. These included NRT in hospital inpatients (2 studies, n = 1078, RR 1.23, 95% CI 0.94 to 1.60, I² = 0%), NRT in assisted abstainers (2 studies, n = 553, RR 1.04, 95% CI 0.77 to 1.40, I² = 0%; low-certainty evidence), extended bupropion in assisted abstainers (6 studies, n = 1697, RR 1.15, 95% CI 0.98 to 1.35, I² = 0%; moderate-certainty evidence), and bupropion plus NRT (2 studies, n = 243, RR 1.18, 95% CI 0.75 to 1.87, I² = 66%; low-certainty evidence). Analyses of behavioural interventions in abstainers did not detect an effect. These included studies in abstinent pregnant and postpartum women at the end of pregnancy (8 studies, n = 1523, RR 1.05, 95% CI 0.99 to 1.11, I² = 0%) and at postpartum follow-up (15 studies, n = 4606, RR 1.02, 95% CI 0.94 to 1.09, I² = 3%), studies in hospital inpatients (5 studies, n = 1385, RR 1.10, 95% CI 0.82 to 1.47, I² = 58%), and studies in assisted abstainers (11 studies, n = 5523, RR 0.98, 95% CI 0.87 to 1.11, I² = 52%; moderate-certainty evidence) and unaided abstainers (5 studies, n = 3561, RR 1.06, 95% CI 0.96 to 1.16, I² = 1%) from the general population.

AUTHORS' CONCLUSIONS

Behavioural interventions that teach people to recognise situations that are high risk for relapse along with strategies to cope with them provided no worthwhile benefit in preventing relapse in assisted abstainers, although unexplained statistical heterogeneity means we are only moderately certain of this. In people who have successfully quit smoking using pharmacotherapy, there were mixed results regarding extending pharmacotherapy for longer than is standard. Extended treatment with varenicline helped to prevent relapse; evidence for the effect estimate was of moderate certainty, limited by unexplained statistical heterogeneity. Moderate-certainty evidence, limited by imprecision, did not detect a benefit from extended treatment with bupropion, though confidence intervals mean we could not rule out a clinically important benefit at this stage. Low-certainty evidence, limited by imprecision, did not show a benefit of extended treatment with nicotine replacement therapy in preventing relapse in assisted abstainers. More research is needed in this area, especially as the evidence for extended nicotine replacement therapy in unassisted abstainers did suggest a benefit.

Relapse prevention interventions for smoking cessation

BACKGROUND

A number of treatments can help smokers make a successful quit attempt, but many initially successful quitters relapse over time. Several interventions have been proposed to help prevent relapse.

OBJECTIVES

To assess whether specific interventions for relapse prevention reduce the proportion of recent quitters who return to smoking.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group trials register, clinicaltrials.gov, and the ICTRP in February 2018 for studies mentioning relapse prevention or maintenance in their title, abstracts, or keywords.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of relapse prevention interventions with a minimum follow-up of six months. We included smokers who quit on their own, were undergoing enforced abstinence, or were participating in treatment programmes. We included studies that compared relapse prevention interventions with a no intervention control, or that compared a cessation programme with additional relapse prevention components with a cessation programme alone.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 77 studies (67,285 participants), 15 of which are new to this update. We judged 21 studies to be at high risk of bias, 51 to be at unclear risk of bias, and five studies to be at low risk of bias. Forty-eight studies included abstainers, and 29 studies helped people to quit and then tested treatments to prevent relapse. Twenty-six studies focused on special populations who were abstinent because of pregnancy (18 studies), hospital admission (five studies), or military service (three studies). Most studies used behavioural interventions that tried to teach people skills to cope with the urge to smoke, or followed up with additional support. Some studies tested extended pharmacotherapy.We focused on results from those studies that randomised abstainers, as these are the best test of relapse prevention interventions. Of the 12 analyses we conducted in abstainers, three pharmacotherapy analyses showed benefits of the intervention: extended varenicline in assisted abstainers (2 studies, n = 1297, risk ratio (RR) 1.23, 95% confidence interval (CI) 1.08 to 1.41, I² = 82%; moderate certainty evidence), rimonabant in assisted abstainers (1 study, RR 1.29, 95% CI 1.08 to 1.55), and nicotine replacement therapy (NRT) in unaided abstainers (2 studies, n = 2261, RR 1.24, 95% Cl 1.04 to 1.47, I² = 56%). The remainder of analyses of pharmacotherapies in abstainers had wide confidence intervals consistent with both no effect and a statistically significant effect in favour of the intervention. These included NRT in hospital inpatients (2 studies, n = 1078, RR 1.23, 95% CI 0.94 to 1.60, I² = 0%), NRT in assisted abstainers (2 studies, n = 553, RR 1.04, 95% CI 0.77 to 1.40, I² = 0%; low certainty evidence), extended bupropion in assisted abstainers (6 studies, n = 1697, RR 1.15, 95% CI 0.98 to 1.35, I² = 0%; moderate certainty evidence), and bupropion plus NRT (2 studies, n = 243, RR 1.18, 95% CI 0.75 to 1.87, I² = 66%; low certainty evidence). Analyses of behavioural interventions in abstainers did not detect an effect. These included studies in abstinent pregnant and postpartum women at end of pregnancy (8 studies, n = 1523, RR 1.05, 95% CI 0.99 to 1.11, I² = 0%) and at postpartum follow-up (15 studies, n = 4606, RR 1.02, 95% CI 0.94 to 1.09, I² = 3%), studies in hospital inpatients (4 studies, n = 1300, RR 0.95, 95% CI 0.81 to 1.11, I² = 0%), and studies in assisted abstainers (10 studies, n = 5408, RR 0.99, 95% CI 0.87 to 1.13, I² = 56%; moderate certainty evidence) and unaided abstainers (5 studies, n = 3561, RR 1.06, 95% CI 0.96 to 1.16, I² = 1%) from the general population.

AUTHORS' CONCLUSIONS

Behavioural interventions that teach people to recognise situations that are high risk for relapse along with strategies to cope with them provided no worthwhile benefit in preventing relapse in assisted abstainers, although unexplained statistical heterogeneity means we are only moderately certain of this. In people who have successfully quit smoking using pharmacotherapy, there were mixed results regarding extending pharmacotherapy for longer than is standard. Extended treatment with varenicline helped to prevent relapse; evidence for the effect estimate was of moderate certainty, limited by unexplained statistical heterogeneity. Moderate-certainty evidence, limited by imprecision, did not detect a benefit from extended treatment with bupropion, though confidence intervals mean we could not rule out a clinically important benefit at this stage. Low-certainty evidence, limited by imprecision, did not show a benefit of extended treatment with nicotine replacement therapy in preventing relapse in assisted abstainers. More research is needed in this area, especially as the evidence for extended nicotine replacement therapy in unassisted abstainers did suggest a benefit.

Nicotine replacement therapy versus control for smoking cessation

BACKGROUND

Nicotine replacement therapy (NRT) aims to temporarily replace much of the nicotine from cigarettes to reduce motivation to smoke and nicotine withdrawal symptoms, thus easing the transition from cigarette smoking to complete abstinence.

OBJECTIVES

To determine the effectiveness and safety of nicotine replacement therapy (NRT), including gum, transdermal patch, intranasal spray and inhaled and oral preparations, for achieving long-term smoking cessation, compared to placebo or 'no NRT' interventions.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group trials register for papers mentioning 'NRT' or any type of nicotine replacement therapy in the title, abstract or keywords. Date of most recent search is July 2017.

SELECTION CRITERIA

Randomized trials in people motivated to quit which compared NRT to placebo or to no treatment. We excluded trials that did not report cessation rates, and those with follow-up of less than six months, except for those in pregnancy (where less than six months, these were excluded from the main analysis). We recorded adverse events from included and excluded studies that compared NRT with placebo. Studies comparing different types, durations, and doses of NRT, and studies comparing NRT to other pharmacotherapies, are covered in separate reviews.

DATA COLLECTION AND ANALYSIS

Screening, data extraction and 'Risk of bias' assessment followed standard Cochrane methods. The main outcome measure was abstinence from smoking after at least six months of follow-up. We used the most rigorous definition of abstinence for each trial, and biochemically validated rates if available. We calculated the risk ratio (RR) for each study. Where appropriate, we performed meta-analysis using a Mantel-Haenszel fixed-effect model.

MAIN RESULTS

We identified 136 studies; 133 with 64,640 participants contributed to the primary comparison between any type of NRT and a placebo or non-NRT control group. The majority of studies were conducted in adults and had similar numbers of men and women. People enrolled in the studies typically smoked at least 15 cigarettes a day at the start of the studies. We judged the evidence to be of high quality; we judged most studies to be at high or unclear risk of bias but restricting the analysis to only those studies at low risk of bias did not significantly alter the result. The RR of abstinence for any form of NRT relative to control was 1.55 (95% confidence interval (CI) 1.49 to 1.61). The pooled RRs for each type were 1.49 (95% CI 1.40 to 1.60, 56 trials, 22,581 participants) for nicotine gum; 1.64 (95% CI 1.53 to 1.75, 51 trials, 25,754 participants) for nicotine patch; 1.52 (95% CI 1.32 to 1.74, 8 trials, 4439 participants) for oral tablets/lozenges; 1.90 (95% CI 1.36 to 2.67, 4 trials, 976 participants) for nicotine inhalator; and 2.02 (95% CI 1.49 to 2.73, 4 trials, 887 participants) for nicotine nasal spray. The effects were largely independent of the definition of abstinence, the intensity of additional support provided or the setting in which the NRT was offered. A subset of six trials conducted in pregnant women found a statistically significant benefit of NRT on abstinence close to the time of delivery (RR 1.32, 95% CI 1.04 to 1.69; 2129 participants); in the four trials that followed up participants post-partum the result was no longer statistically significant (RR 1.29, 95% CI 0.90 to 1.86; 1675 participants). Adverse events from using NRT were related to the type of product, and include skin irritation from patches and irritation to the inside of the mouth from gum and tablets. Attempts to quantitatively synthesize the incidence of various adverse effects were hindered by extensive variation in reporting the nature, timing and duration of symptoms. The odds ratio (OR) of chest pains or palpitations for any form of NRT relative to control was 1.88 (95% CI 1.37 to 2.57, 15 included and excluded trials, 11,074 participants). However, chest pains and palpitations were rare in both groups and serious adverse events were extremely rare.

AUTHORS' CONCLUSIONS

There is high-quality evidence that all of the licensed forms of NRT (gum, transdermal patch, nasal spray, inhalator and sublingual tablets/lozenges) can help people who make a quit attempt to increase their chances of successfully stopping smoking. NRTs increase the rate of quitting by 50% to 60%, regardless of setting, and further research is very unlikely to change our confidence in the estimate of the effect. The relative effectiveness of NRT appears to be largely independent of the intensity of additional support provided to the individual. Provision of more intense levels of support, although beneficial in facilitating the likelihood of quitting, is not essential to the success of NRT. NRT often causes minor irritation of the site through which it is administered, and in rare cases can cause non-ischaemic chest pain and palpitations.

Extended treatment for cigarette smoking cessation: a randomized control trial

AIM

To test the potential benefit of extending cognitive-behavioral therapy (CBT) relative to not extending CBT on long-term abstinence from smoking.

DESIGN

Two-group parallel randomized controlled trial. Patients were randomized to receive non-extended CBT (n = 111) or extended CBT (n = 112) following a 26-week open-label treatment.

SETTING

Community clinic in the United States.

PARTICIPANTS

A total of 219 smokers (mean age: 43 years; mean cigarettes/day: 18).

INTERVENTION

All participants received 10 weeks of combined CBT + bupropion sustained release (bupropion SR) + nicotine patch and were continued on CBT and either no medications if abstinent, continued bupropion + nicotine replacement therapy (NRT) if increased craving or depression scores, or varenicline if still smoking at 10 weeks. Half the participants were randomized at 26 weeks to extended CBT (E-CBT) to week 48 and half to non-extended CBT (no additional CBT sessions).

MEASUREMENTS

The primary outcome was expired CO-confirmed, 7-day point-prevalence (PP) at 52- and 104-week follow-up. Analyses were based on intention-to-treat.

FINDINGS

PP abstinence rates at the 52-week follow-up were comparable across non-extended CBT (40%) and E-CBT (39%) groups [odds ratio (OR) = 0.99; 95% confidence interval (CI) = 0.55, 1.78]. A similar pattern was observed across non-extended CBT (39%) and E-CBT (33%) groups at the 104-week follow-up (OR = 0.79; 95% CI= 0.44, 1.40).

CONCLUSION

Prolonging cognitive-behavioral therapy from 26 to 48 weeks does not appear to improve long-term abstinence from smoking.

Withdrawal exposure with withdrawal regulation training for smoking cessation: a randomized controlled pilot trial

INTRODUCTION

Although withdrawal processes form a key motivational basis for cigarette use, smoking cessation treatments appear to exert only modest effects on withdrawal. One treatment option for further reducing withdrawal severity would be to provide smokers with withdrawal regulation training. The objective of this study was to pilot a smoking cessation intervention comprising withdrawal exposure with withdrawal regulation training.

METHODS

Adult smokers (N=80) were randomized to one of two conditions: 1) Withdrawal Exposure with Withdrawal Regulation Training (WT), which included the development and application of individualized withdrawal regulation strategies over four separate sessions that spanned the first four hours of abstinence; 2) or Relaxation Control (RC) training, which controlled for the therapeutic contact of WT. All sessions occurred before the quit date, after which differential treatment was discontinued and all participants received brief counseling, nicotine replacement therapy, and self-help literature. Biochemically-confirmed (CO≤3) seven-day point-prevalence abstinence was assessed at Months 2 and 3 after end-of-treatment.

RESULTS

Treatment completion and ratings of credibility and efficacy were high and equivalent across conditions. 22.2% of participants in the WT condition were abstinent at both time points, whereas 0% and 4.2% of participants in the RC condition were abstinent at Months 2 and 3 (Month 3 OR=6.5 [0.73, 59.19]). In-session withdrawal ratings suggested WT improved regulation of withdrawal symptoms, which were in turn associated with abstinence.

CONCLUSIONS

This small pilot study suggests that WT promotes abstinence by enhancing withdrawal regulation. Results warrant further investigation of this innovative treatment approach.

A randomized trial of concurrent smoking-cessation and substance use disorder treatment in stimulant-dependent smokers

OBJECTIVE

To evaluate the impact of concurrent treatments for substance use disorder and nicotine-dependence for stimulant-dependent patients.

METHOD

A randomized, 10-week trial with follow-up at 3 and 6 months after smoking quit date conducted at 12 substance use disorder treatment programs between February 2010 and July 2012. Adults meeting DSM-IV-TR criteria for cocaine and/or methamphetamine dependence and interested in quitting smoking were randomized to treatment as usual (n = 271) or treatment as usual with smoking-cessation treatment (n = 267). All participants received treatment as usual for substance use disorder treatment. Participants assigned to treatment as usual with concurrent smoking-cessation treatment received weekly individual smoking cessation counseling and extended-release bupropion (300 mg/d) during weeks 1-10. During post-quit treatment (weeks 4-10), participants assigned to treatment as usual with smoking-cessation treatment received a nicotine inhaler and contingency management for smoking abstinence. Weekly proportion of stimulant-abstinent participants during the treatment phase, as assessed by urine drug screens and self-report, was the primary outcome. Secondary measures included other substance/nicotine use outcomes and treatment attendance.

RESULTS

There were no significant treatment effects on stimulant-use outcomes, as measured by the primary outcome and stimulant-free days, on drug-abstinence, or on attendance. Participants assigned to treatment as usual with smoking-cessation treatment, relative to those assigned to treatment as usual, had significantly better outcomes for drug-free days at 6-month follow-up (χ(2)(1) = 4.09, P <.05), with a decrease in drug-free days from baseline of -1.3% in treatment as usual with smoking-cessation treatment and of -7.6% in treatment as usual. Participants receiving treatment as usual with smoking-cessation treatment, relative to those receiving treatment as usual, had significantly better outcomes on smoking point-prevalence abstinence (25.5% vs 2.2%; χ(2)(1) = 44.69, P < .001; OR =18.2).

CONCLUSIONS

These results suggest that providing smoking-cessation treatment to illicit stimulant-dependent patients in outpatient substance use disorder treatment will not worsen, and may enhance, abstinence from nonnicotine substance use.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01077024.

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.

Nicotinic receptor antagonists as treatments for nicotine abuse

Despite the proven efficacy of current pharmacotherapies for tobacco dependence, relapse rates continue to be high, indicating that novel medications are needed. Currently, several smoking cessation agents are available, including varenicline (Chantix®), bupropion (Zyban®), and cytisine (Tabex®). Varenicline and cytisine are partial agonists at the α4β2* nicotinic acetylcholine receptor (nAChR). Bupropion is an antidepressant but is also an antagonist at α3β2* ganglionic nAChRs. The rewarding effects of nicotine are mediated, in part, by nicotine-evoked dopamine (DA) release leading to sensitization, which is associated with repeated nicotine administration and nicotine addiction. Receptor antagonists that selectivity target central nAChR subtypes mediating nicotine-evoked DA release should have efficacy as tobacco use cessation agents with the therapeutic advantage of a limited side-effect profile. While α-conotoxin MII (α-CtxMII)-insensitive nAChRs (e.g., α4β2*) contribute to nicotine-evoked DA release, these nAChRs are widely distributed in the brain, and inhibition of these receptors may lead to nonselective and untoward effects. In contrast, α-CtxMII-sensitive nAChRs mediating nicotine-evoked DA release offer an advantage as targets for smoking cessation, due to their more restricted localization primarily to dopaminergic neurons. Small drug-like molecules that are selective antagonists at α-CtxMII-sensitive nAChR subtypes that contain α6 and β2 subunits have now been identified. Early research identified a variety of quaternary ammonium analogs that were potent and selective antagonists at nAChRs mediating nicotine-evoked DA release. More recent data have shown that novel, nonquaternary bis-1,2,5,6-tetrahydropyridine analogs potently inhibit (IC50<1nM) nicotine-evoked DA release in vitro by acting as antagonists at α-CtxMII-sensitive nAChR subtypes; these compounds also decrease NIC self-administration in rats.

Achieving smoking abstinence is associated with decreased cocaine use in cocaine-dependent patients receiving smoking-cessation treatment

BACKGROUND

Past research suggests that a significant relationship exists between cigarette smoking and illicit-stimulant abuse. The present study evaluated the association between achieving smoking abstinence in response to smoking-cessation treatment (SCT) and illicit-stimulant abstinence in cocaine- and/or methamphetamine-dependent participants.

METHODS

Secondary analysis of a randomized, 10-week trial conducted at 12 substance use disorder (SUD) treatment programs. Two hundred and sixty seven adults, meeting DSM-IV-TR criteria for cocaine and/or methamphetamine-dependence and interested in quitting smoking were randomized to SUD treatment as usual plus SCT consisting of weekly individual smoking cessation counseling, extended-release (XL) bupropion (300 mg/day), nicotine inhaler, and contingency management for smoking abstinence. Illicit-stimulant-abstinence was measured by self-report and urine drug screens. Smoking abstinence was assessed via self-report and carbon monoxide levels.

RESULTS

A significant effect was found for the cocaine-dependent subsample (N=147) in which participants who stopped smoking were abstinent for illicit stimulants an average of 78.2% of the post-smoking-quit weeks (weeks 4-10) relative to 63.6% in participants who continued smoking (X(2)(1)=8.55, p<.01, d=0.36). No significant effects were found for the sample as a whole (N=249) or for the methamphetamine-dependent subsample (N=102).

CONCLUSIONS

The present results suggest that cocaine-dependent patients achieving smoking abstinence in response to SCT might evidence not only improved smoking outcomes but improved cocaine-use outcomes as well. Future research to replicate this finding appears warranted.

A tale of two stimulants: mentholated cigarettes may play a role in cocaine, but not methamphetamine, dependence

BACKGROUND

Research suggests that mentholated cigarettes may play a role in cocaine dependence. The purpose of the present study was to expand upon the research on mentholated cigarettes and cocaine dependence and to evaluate the role of mentholated cigarettes in methamphetamine dependence.

METHODS

Secondary analysis of a multisite, randomized trial evaluating the impact of smoking-cessation treatment in stimulant-dependent outpatients (N=538). Participants' reasons for concurrent use of cigarettes and illicit stimulants were assessed via self-report. Stimulant-abstinence was measured by self-report and urine drug screens. Smoking cessation was assessed via self-report and carbon monoxide levels.

RESULTS

Of the 301 cocaine-dependent participants, 201 (67%) were menthol and 100 (33%) were non-menthol cigarette smokers. Cocaine-dependent participants who smoked menthol, compared to non-menthol, cigarettes were significantly more likely to report that cigarettes prolong their cocaine high (X(2)(1)=16.3, p<.0001, OR=3.58 [95% CI: 1.88-6.79]) and were less likely to be stimulant abstinent during active treatment (W=3.6, p<0.001, d=.39 [95% CI: 0.16-0.62]), at 3-month follow-up (X(2)(1)=14.4, p<0.001, OR=.32 [95% CI: 0.17-0.58]), and at 6-month follow-up (X(2)(1)=4.6, p=0.03, OR=.53 [95% CI: 0.29-0.95]). No parallel differences were found between menthol and non-menthol methamphetamine-dependent smokers. The prevalence of Caucasian menthol smokers was significantly greater in the cocaine-dependent participants (37.2%) than in the methamphetamine-dependent participants (17.61%), (X(2)(1)=14.4, p<.001, OR=2.77 [95% CI:1.62-4.73]). Smoking cessation was not significantly associated with cigarette type for either cocaine- or methamphetamine-dependent participants.

CONCLUSIONS

The present results suggest that mentholated cigarettes play a role in cocaine, but not methamphetamine, dependence.

Relapse prevention interventions for smoking cessation

BACKGROUND

A number of treatments can help smokers make a successful quit attempt, but many initially successful quitters relapse over time. Several interventions have been proposed to help prevent relapse.

OBJECTIVES

To assess whether specific interventions for relapse prevention reduce the proportion of recent quitters who return to smoking.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group trials register in May 2013 for studies mentioning relapse prevention or maintenance in title, abstracts or keywords.

SELECTION CRITERIA

Randomized or quasi-randomized controlled trials of relapse prevention interventions with a minimum follow-up of six months. We included smokers who quit on their own, were undergoing enforced abstinence, or were participating in treatment programmes. We included trials that compared relapse prevention interventions with a no intervention control, or that compared a cessation programme with additional relapse prevention components with a cessation programme alone.

DATA COLLECTION AND ANALYSIS

Studies were screened and data extracted by one review author, and checked by a second. Disagreements were resolved by discussion or by referral to a third review author.

MAIN RESULTS

Sixty-three studies met inclusion criteria but were heterogeneous in terms of populations and interventions. We considered 41 studies that randomly assigned abstainers separately from studies that randomly assigned participants before their quit date.Upon looking at studies of behavioural interventions that randomly assigned abstainers, we detected no benefit of brief and 'skills-based' relapse prevention methods for women who had quit smoking because of pregnancy, or for smokers undergoing a period of enforced abstinence during hospitalisation or military training. We also failed to detect significant effects of behavioural interventions in trials in unselected groups of smokers who had quit on their own or through a formal programme. Amongst trials randomly assigning smokers before their quit date and evaluating the effects of additional relapse prevention components, we found no evidence of benefit of behavioural interventions or combined behavioural and pharmacotherapeutic interventions in any subgroup. Overall, providing training in skills thought to be needed for relapse avoidance did not reduce relapse, but most studies did not use experimental designs best suited to the task and had limited power to detect expected small differences between interventions. For pharmacological interventions, extended treatment with varenicline significantly reduced relapse in one trial (risk ratio (RR) 1.18, 95% confidence interval (CI) 1.03 to 1.36). Pooling of six studies of extended treatment with bupropion failed to detect a significant effect (RR 1.15, 95% CI 0.98 to 1.35). Two small trials of oral nicotine replacement treatment (NRT) failed to detect an effect, but treatment compliance was low, and in two other trials of oral NRT in which short-term abstainers were randomly assigned, a significant effect of intervention was noted.

AUTHORS' CONCLUSIONS

At the moment, there is insufficient evidence to support the use of any specific behavioural intervention to help smokers who have successfully quit for a short time to avoid relapse. The verdict is strongest for interventions focused on identifying and resolving tempting situations, as most studies were concerned with these. Little research is available regarding other behavioural approaches.Extended treatment with varenicline may prevent relapse. Extended treatment with bupropion is unlikely to have a clinically important effect. Studies of extended treatment with nicotine replacement are needed.

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.

Interventions to address chronic disease and HIV: strategies to promote smoking cessation among HIV-infected individuals

Tobacco use, especially cigarette smoking, is higher than average in persons living with HIV/AIDS (PLWHA). The Public Health Service Clinical Practice Guideline for Treating Tobacco Use and Dependence states that, during every medical encounter, all smokers should be offered smoking cessation counseling, along with approved medications. The Guideline also recognizes PLWHA as a priority population, given the scarcity of research on effective cessation treatments in this group. The scant evidence suggests that conventional treatments, though worthwhile, are not as successful as might be hoped for. The reasons for this are not entirely clear, but may have to do with the complex array of medical and psychosocial factors that complicate their lives. Clinicians should consider re-treatment strategies for those patients who encounter difficulty when quitting smoking with conventional approaches, switching or augmenting treatments as needed to minimize adverse experiences, and to maximize tolerability, adherence, and cessation outcomes.

Nicotine replacement therapy for smoking cessation

BACKGROUND

The aim of nicotine replacement therapy (NRT) is to temporarily replace much of the nicotine from cigarettes to reduce motivation to smoke and nicotine withdrawal symptoms, thus easing the transition from cigarette smoking to complete abstinence.

OBJECTIVES

The aims of this review were: To determine the effect of NRT compared to placebo in aiding smoking cessation, and to consider whether there is a difference in effect for the different forms of NRT (chewing gum, transdermal patches, oral and nasal sprays, inhalers and tablets/lozenges) in achieving abstinence from cigarettes. To determine whether the effect is influenced by the dosage, form and timing of use of NRT; the intensity of additional advice and support offered to the smoker; or the clinical setting in which the smoker is recruited and treated. To determine whether combinations of NRT are more likely to lead to successful quitting than one type alone. To determine whether NRT is more or less likely to lead to successful quitting compared to other pharmacotherapies.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group trials register for papers mentioning 'NRT' or any type of nicotine replacement therapy in the title, abstract or keywords. Date of most recent search July 2012.

SELECTION CRITERIA

Randomized trials in which NRT was compared to placebo or to no treatment, or where different doses of NRT were compared. We excluded trials which did not report cessation rates, and those with follow-up of less than six months.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate on the type of participants, the dose, duration and form of nicotine therapy, the outcome measures, method of randomization, and completeness of follow-up. The main outcome measure was abstinence from smoking after at least six months of follow-up. We used the most rigorous definition of abstinence for each trial, and biochemically validated rates if available. We calculated the risk ratio (RR) for each study. Where appropriate, we performed meta-analysis using a Mantel-Haenszel fixed-effect model.

MAIN RESULTS

We identified 150 trials; 117 with over 50,000 participants contributed to the primary comparison between any type of NRT and a placebo or non-NRT control group. The risk ratio (RR) of abstinence for any form of NRT relative to control was 1.60 (95% confidence interval [CI] 1.53 to 1.68). The pooled RRs for each type were 1.49 (95% CI 1.40 to 1.60, 55 trials) for nicotine gum; 1.64 (95% CI 1.52 to 1.78, 43 trials) for nicotine patch; 1.95 (95% CI 1.61 to 2.36, 6 trials) for oral tablets/lozenges; 1.90 (95% CI 1.36 to 2.67, 4 trials) for nicotine inhaler; and 2.02 (95% CI 1.49 to 2.73, 4 trials) for nicotine nasal spray. One trial of oral spray had an RR of 2.48 (95% CI 1.24 to 4.94). The effects were largely independent of the duration of therapy, the intensity of additional support provided or the setting in which the NRT was offered. The effect was similar in a small group of studies that aimed to assess use of NRT obtained without a prescription. In highly dependent smokers there was a significant benefit of 4 mg gum compared with 2 mg gum, but weaker evidence of a benefit from higher doses of patch. There was evidence that combining a nicotine patch with a rapid delivery form of NRT was more effective than a single type of NRT (RR 1.34, 95% CI 1.18 to 1.51, 9 trials). The RR for NRT used for a short period prior to the quit date was 1.18 (95% CI 0.98 to 1.40, 8 trials), just missing statistical significance, though the efficacy increased when we pooled only patch trials and when we removed one trial in which confounding was likely. Five studies directly compared NRT to a non-nicotine pharmacotherapy, bupropion; there was no evidence of a difference in efficacy (RR 1.01; 95% CI 0.87 to 1.18). A combination of NRT and bupropion was more effective than bupropion alone (RR 1.24; 95% CI 1.06 to 1.45, 4 trials). Adverse effects from using NRT are related to the type of product, and include skin irritation from patches and irritation to the inside of the mouth from gum and tablets. There is no evidence that NRT increases the risk of heart attacks.

AUTHORS' CONCLUSIONS

All of the commercially available forms of NRT (gum, transdermal patch, nasal spray, inhaler and sublingual tablets/lozenges) can help people who make a quit attempt to increase their chances of successfully stopping smoking. NRTs increase the rate of quitting by 50 to 70%, regardless of setting. The effectiveness of NRT appears to be largely independent of the intensity of additional support provided to the individual. Provision of more intense levels of support, although beneficial in facilitating the likelihood of quitting, is not essential to the success of NRT.

Tobacco dependence counseling in a randomized multisite clinical trial

Pharmacotherapy trials for treating tobacco dependence would benefit from behavioral interventions providing treatment consistent with clinical practice guidelines but not directing participants to treatments not evaluated in the trial. The Smoke Free and Living It© behavioral intervention manual includes participant and interventionist guides and is designed to provide both practical counseling and intra-treatment support. We utilized this intervention manual in a multicenter, randomized clinical trial of smokers with attention deficit hyperactivity disorder. In this study, we evaluated how the interventional manual performed in a "train-the-trainer" model requiring uniform counseling across 6 sites and 15 interventionists. We analyzed the skill-adherence of the interventionists and the intervention-adherence of the participants. The 255 randomized participants completed 9.3±2.8 sessions (mean±SD), with 157 participants (61.6%) completing all 11 of the sessions and 221 (86.7%) completing at least 6 of the 11 sessions. Of the 163 sessions for which the study interventionists were evaluated, 156 (95.7%) were rated as adherent to protocol and "meeting expectations" on at least 6 of 7 established criteria, illustrating that fidelity can be maintained with minimal supervision. The self-help and interventionists guides of the Smoke Free and Living It manual can thus be used to provide behavioral intervention with a high rate of adherence by both the interventionists and the participants. This manual meets the requirements of the United States Public Health Service Clinical Practice Guideline, can be adapted to specific research protocols, and provides a useful option for behavioral intervention during clinical trials for smoking cessation.

Smoking Relapse Prevention Programs and Factors That Predict Abstinence: A Controlled Study Comparing the Efficacy of Workplace Group Counselling and Proactive Phone Counselling

Aims:Most smokers who quit smoking usually relapse. Smoking relapse prevention programs are thus needed and their optimal content and duration should be therefore studied. The present study aimed to compare the efficacy of two relapse prevention programs designed for subjects who reported to be abstinent after a smoking cessation program and to assess predictors of abstinence 9 months later.Participants and design:Two-hundred and seventy-five adults who reported to be abstinent were randomised in two 9-month relapse prevention programs: Workplace Group Counselling Program (WGC) or Proactive Phone Counselling Program (PPC).Measurements:Assessment included questionnaires (Brief Symptom Inventory, BSI; Dutch Eating Behavior Questionnaire, DEBQ; Life Event Scale; sociodemographic and companies' characteristics; and companies' policy toward smoking), and abstinence measurements (self-report, breath carbon monoxide level and urinary cotinine concentration level).Findings:Quit rates at 9 months were respectively 57.5% in the PPC arm and 61.7% in the WGC arm (p= .552). Regression analysis indicated that urinary cotinine concentration level lower than or equal to 317ng/ml was associated with higher rate of abstinence (OR= 4.75, 95% CI = 1.23–18.30,p= .024). Moreover having higher BSI global severity index (OR= .36; 95% CI = .15–.83;p= .017), DEBQ external eating scores (OR= .67; 95% CI = .45–1.00;p= .050) and a free program (OR= .46; 95% CI = .22–.99;p= .048) were associated with lower rate of abstinence.Conclusions:Efficacy was similar for the two programs. This study underlines the need to monitor distress, eating behaviours, lapses and motivation, and to include in future relapse prevention programs specific psychological and/or pharmacological interventions that consider these dimensions.

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.

Design considerations for a study to evaluate the impact of smoking cessation treatment on stimulant use outcomes in stimulant-dependent individuals

Cigarette smoking is prevalent in cocaine/methamphetamine-dependent patients and associated with significant morbidity and mortality, yet, the provision of smoking cessation treatment in conjunction with substance use disorder (SUD) treatment is not standard practice. This is due, in part, to clinician concern that combining smoking cessation treatment with SUD treatment could lead to poorer SUD outcomes. The NIDA Clinical Trials Network is conducting a 10-week, two-group, randomized trial to evaluate the impact of providing smoking cessation treatment (SCT) with SUD treatment as usual (TAU), compared to TAU alone, in smokers who are in outpatient treatment for cocaine or methamphetamine dependence. Approximately 528 participants, recruited from 12 community treatment programs, will be randomized into the trial. The present paper describes key design decisions made during protocol development. The trial is designed to evaluate the relationship between cigarette smoking and stimulant use, which prior research suggests is linked, and should contribute to our understanding of how best to address the co-occurring problems of nicotine dependence and cocaine/methamphetamine-dependence. Unique aspects of the trial include the primary question of interest, which concerns the impact of providing SCT on SUD outcomes rather than on smoking outcomes, and the intensity of the SCT chosen, which includes bupropion, nicotine replacement, and two psychosocial interventions.

Using extended cognitive behavioral treatment and medication to treat dependent smokers

OBJECTIVES

We evaluated smoking-cessation efficacy of an extended course of sustained-release bupropion (bupropion SR) and cognitive-behavioral treatment (CBT).

METHODS

Participants who smoked at least 10 cigarettes per day and who smoked within 30 minutes of arising (n = 406) completed a 12-week smoking-cessation treatment including group counseling, nicotine-replacement therapy, and bupropion SR. Participants were then randomly assigned to 1 of 5 conditions: (1) no further treatment, (2) active bupropion SR for 40 weeks, (3) placebo for 40 weeks, (4) active bupropion SR and 11 sessions of CBT for 40 weeks (A-CBT), or (5) placebo and 11 sessions of CBT for 40 weeks. Participants were assessed at baseline and at weeks 12, 24, 52, 64, and 104.

RESULTS

A-CBT was not superior to the other 3 extended treatments. From weeks 12 through 104, all extended treatment conditions were superior to standard treatment. At weeks 64 and 104, the 2 CBT conditions produced significantly higher abstinence rates than did the other 3 conditions.

CONCLUSIONS

Brief contact with providers can increase abstinence during treatment. CBT may increase long-term abstinence after extended treatment is terminated.

Indolizidine (-)-235B' and related structural analogs: discovery of nicotinic receptor antagonists that inhibit nicotine-evoked [3H]dopamine release

Although several therapeutic agents are available to aid in tobacco smoking cessation, relapse rates continue to be high, warranting the development of alternative pharmacotherapies. Nicotine-evoked dopamine release from its presynaptic terminals in the central nervous system leads to reward which maintains continued tobacco use. The ability of indolizidine (-)-235B' and a sub-library of structurally related analogs to inhibit nicotine-evoked [(3)H]dopamine release from rat striatal slices was determined in the current study. Indolizidine (-)-235B' inhibited nicotine-evoked [(3)H]dopamine release in a concentration-dependent manner (IC(50)=42 nM, I(max)=55%). Compound (-)-237D, the double bond-reduced analog, afforded the greatest inhibitory potency (IC(50)=0.18 nM, I(max)=76%), and was 233-fold more potent than indolizidine (-)-235B'. The des-8-methyl aza-analog of indolizidine (-)-235B', ZZ-272, also inhibited nicotine-evoked [(3)H]dopamine release (IC(50)=413 nM, I(max)=59%). Concomitant exposure to maximally effective concentrations of indolizidine (-)-235B', ZZ-272 or (-)-237D with a maximally effective concentration of α-conotoxin MII, a selective antagonist for α6β2-containing nicotinic receptors, resulted in inhibition of nicotine-evoked [(3)H]dopamine release no greater than that produced by each compound alone. The latter results suggest that indolizidine (-)-235B', (-)-237D, ZZ-272 and α-conotoxin MII inhibit the same α-conotoxin MII-sensitive nicotinic receptor subtypes. Thus, indolizidine (-)-235B' and its analogs act as antagonists of α6β2-nicotinic receptors and constitute a novel structural scaffold for the discovery of pharmacotherapies for smoking cessation.

Impact of attention-deficit/hyperactivity disorder (ADHD) treatment on smoking cessation intervention in ADHD smokers: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

High smoking rates in adults with attention-deficit/hyperactivity disorder (ADHD) and nicotine's amelioration of ADHD suggest that effective ADHD treatment might facilitate abstinence in smokers with ADHD. The present study evaluated if using osmotic-release oral system methylphenidate (OROS-MPH) to treat ADHD enhances response to smoking cessation treatment in smokers with ADHD.

METHOD

A randomized, double-blind, placebo-controlled, 11-week trial with a 1-month follow-up was conducted at 6 clinical sites between December 2005 and January 2008. Adults (aged 18-55 years) meeting DSM-IV criteria for ADHD and interested in quitting smoking were randomly assigned to OROS-MPH titrated to 72 mg/d (n = 127) or placebo (n = 128). All participants received brief weekly individual smoking cessation counseling for 11 weeks and 21 mg/d nicotine patches starting on the smoking quit day (day 27) through study week 11. Outcome measures included prolonged smoking abstinence and DSM-IV ADHD Rating Scale (ADHD-RS) score.

RESULTS

Of 255 randomly assigned participants, 204 (80%) completed the trial. Prolonged abstinence rates, 43.3% and 42.2%, for the OROS-MPH and placebo groups, respectively, did not differ significantly (OR = 1.1; 95% CI, 0.63-1.79; P = .81). Relative to placebo, OROS-MPH evidenced a greater reduction in DSM-IV ADHD-RS score (P < .0001) and in cigarettes per day during the post-quit phase (P = .016). Relative to placebo, OROS-MPH increased blood pressure and heart rate to a statistically, but not clinically, significant degree (P < .05); medication discontinuation did not differ significantly between treatments.

CONCLUSIONS

Treatment for ADHD did not improve smoking cessation success; OROS-MPH, relative to placebo, effectively treated ADHD and was safe and generally well tolerated in this healthy sample of adult ADHD smokers.

TRIAL REGISTRATION

clinical trials.gov Identifier: NCT00253747.

A systematic review of the effectiveness of smoking relapse prevention interventions for abstinent smokers

AIMS

To carry out a systematic review of the effectiveness of relapse prevention interventions (RPIs) among abstinent smokers who had completed an initial course of treatment or who had abstained unassisted, pooling only outcome data from similar follow-up time points.

METHODS

We used the same search strategy as was used in Cochrane reviews of RPIs to identify randomized trials of behavioural and pharmacological studies of smoking RPIs published up to July 2008. Abstinence from smoking was defined as either continuous abstinence or point prevalence abstinence, measured at three follow-up time points: short term (1-3 months post randomization), medium term (6-9 months) and long term (12-18 months). Abstinence among pregnant/postpartum women was also measured at delivery or the last follow-up prior to delivery. Random effect meta-analysis was used to estimate pooled odds ratios (OR) with 95% confidence intervals (CI).

RESULTS

Thirty-six studies randomizing abstainers were included. Self-help materials appeared to be effective in preventing relapse at long-term follow up in initially unaided quitters (pooled OR 1.52; 95% CI 1.15 to 2.01, I2 = 0%, NNT = 11, 3 studies). Other behavioural interventions for relapse prevention appeared effective in the short term only. There were positive results for the use of pharmacotherapies for relapse prevention. Bupropion was effective at long-term follow-up (pooled OR 1.49; 95% CI 1.10 to 2.01; I2 = 0%; NNT = 11; 4 studies). Nicotine replacement therapy (NRT) was effective at medium-term (pooled OR 1.56; 95% CI 1.16 to 2.11; I2 = 37%; NNT = 14; 4 trials) and long-term follow-ups (pooled OR 1.33; 95% CI 1.08 to 1.63; I2 = 0%; NNT = 20; 4 trials). Single trials of extended treatment of Varenicline and rimonabant were also found to be effective at short-term and medium-term follow-ups.

CONCLUSIONS

Self-help materials appear to prevent relapse in initially unaided quitters. Use of NRT, bupropion and varenicline appears to be effective in preventing relapse following an initial period of abstinence or an acute treatment episode. There is currently no good evidence that behavioural support prevents relapse after initial unaided abstinence or following an acute treatment period.

Effectiveness of complex psycho-educational interventions for smoking relapse prevention: an exploratory meta-analysis

BACKGROUND

Existing systematic reviews have concluded that psycho-educational interventions for smoking relapse prevention were ineffective. Our objective was to conduct an exploratory meta-analysis, guided by mechanisms of these complex interventions for preventing smoking relapse.

METHODS

Relevant trials were identified from a Cochrane review and by an updated search of MEDLINE and PsycINFO (up to August 2009). We examined theories or mechanisms underlying relapse prevention interventions, and process variables reported in trials. Odds ratios (ORs) for the rate of smoking abstinence at the longest follow-up were pooled in meta-analysis.

RESULTS

Forty-nine trials were included, and interventions were at least partly based on the cognitive-behavioural approach to coping skills training in 41 trials. Only a few trials reported data on process variables. Coping skills training for smoking relapse prevention was effective for community quitters (OR 1.27, 95% CI: 1.08-1.49), and particularly for those who stopped smoking for at least 1 week at baseline (OR 1.52, 95% CI: 1.20-1.93). These findings were interpretable with mechanisms of coping skills training for relapse prevention.

CONCLUSIONS

On the basis of post hoc subgroup analyses, coping skills training for smoking relapse prevention is effective for motivated community quitters. This finding has important public health implications and needs to be confirmed by further trials.

A randomized placebo-controlled clinical trial of 5 smoking cessation pharmacotherapies

CONTEXT

Little direct evidence exists on the relative efficacies of different smoking cessation pharmacotherapies, yet such evidence is needed to make informed decisions about their clinical use.

OBJECTIVE

To assess the relative efficacies of 5 smoking cessation pharmacotherapy interventions using placebo-controlled, head-to-head comparisons.

DESIGN

A randomized, double-blind, placebo-controlled clinical trial.

SETTING

Two urban research sites.

PATIENTS

One thousand five hundred four adults who smoked at least 10 cigarettes per day during the past 6 months and reported being motivated to quit smoking. Participants were excluded if they reported using any form of tobacco other than cigarettes; current use of bupropion; having a current psychosis or schizophrenia diagnosis; or having medical contraindications for any of the study medications.

INTERVENTIONS

Participants were randomized to 1 of 6 treatment conditions: nicotine lozenge, nicotine patch, sustained-release bupropion, nicotine patch plus nicotine lozenge, bupropion plus nicotine lozenge, or placebo. In addition, all participants received 6 individual counseling sessions.

MAIN OUTCOME MEASURES

Biochemically confirmed 7-day point-prevalence abstinence assessed at 1 week after the quit date (postquit), end of treatment (8 weeks postquit), and 6 months postquit. Other outcomes were initial cessation, number of days to lapse, number of days to relapse, and latency to relapse after the first lapse.

RESULTS

All pharmacotherapies differed from placebo when examined without protection for multiple comparisons (odds ratios, 1.63-2.34). With such protection, only the nicotine patch plus nicotine lozenge (odds ratio, 2.34, P < .001) produced significantly higher abstinence rates at 6-month postquit than did placebo.

CONCLUSION

While the nicotine lozenge, bupropion, and bupropion plus lozenge produced effects that were comparable with those reported in previous research, the nicotine patch plus lozenge produced the greatest benefit relative to placebo for smoking cessation.

Nicotinic receptor-based therapeutics and candidates for smoking cessation

Tobacco dependence is the most preventable cause of death and is a chronic, relapsing disorder in which compulsive tobacco use persists despite known negative health consequences. All currently available cessation agents (nicotine, varenicline and bupropion) have limited efficacy and are associated with high relapse rates, revealing a need for more efficacious, alternative pharmacotherapies. The major alkaloid in tobacco, nicotine, activates nicotinic receptors (nAChRs) which increase brain extracellular dopamine producing nicotine reward leading to addiction. nAChRs are located primarily presynaptically and modulate synaptic activity by regulating neurotransmitter release. Subtype-selective nAChR antagonists that block reward-relevant mesocorticolimbic and nigrostriatal dopamine release induced by nicotine may offer advantages over current therapies. An innovative approach is to provide pharmacotherapies which are antagonists at nAChR subtypes mediating nicotine evoked dopamine release. In addition, providing multiple medications with a wider array of targets and mechanisms should provide more treatment options for individuals who are not responsive to the currently available pharmacotherapies. This review summarizes the currently available smoking cessation therapies and discusses emerging potential therapeutic approaches employing pharmacological agents which act as antagonists at nicotinic receptors.

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.

A randomized, controlled trial of bupropion sustained-release for preventing tobacco relapse in recovering alcoholics

INTRODUCTION

Studies examining the efficacy of tobacco dependence treatment among recovering alcoholic smokers have produced mixed findings. We set out to investigate this issue further by conducting a randomized, double-blind, placebo-controlled trial of bupropion sustained-release (SR) for smoking relapse prevention among abstinent alcoholic smokers.

METHODS

Participants (N = 195) met DSM-IV criteria for a history of alcohol abuse or dependence and had at least 1 year of continuous abstinence from alcohol and drugs. Open-label treatment with nicotine patch therapy was provided to all subjects for 8 weeks. The initial nicotine patch dose was determined by the subject's baseline serum cotinine concentration with an aim to achieve 100% cotinine replacement. All subjects who were confirmed abstinent from smoking throughout the final week of nicotine patch therapy (Week 8) were randomly assigned to receive bupropion SR 300 mg/day or placebo through Week 52.

RESULTS

A total of 110 participants were randomized to the double-blind treatment. No significant difference was observed between the bupropion and placebo groups for rates of continuous smoking abstinence, 41.1% (95% CI = 28.1%-55.0%) versus 40.7% (95% CI = 27.6%-55.0%), respectively, p = 1.0, or point prevalence abstinence, 39.3% (95% CI = 26.5%-53.3%) versus 40.7% (95% CI = 27.6%-55.0%), respectively, p = 1.0, at the end of the treatment (Week 52). Relapse to alcohol occurred in 4% of subjects (n = 4) during the study.

DISCUSSION

Treatment with bupropion SR among abstinent alcoholic smokers did not delay relapse or result in improved long-term smoking abstinence.

Extended treatment of older cigarette smokers

AIMS

Tobacco dependence treatments achieve abstinence rates of 25-30% at 1 year. Low rates may reflect failure to conceptualize tobacco dependence as a chronic disorder. The aims of the present study were to determine the efficacy of extended cognitive behavioral and pharmacological interventions in smokers > or = 50 years of age, and to determine if gender differences in efficacy existed.

DESIGN

Open randomized clinical trial.

SETTING

A free-standing, smoking treatment research clinic.

PARTICIPANTS

A total of 402 smokers of > or = 10 cigarettes per day, all 50 years of age or older.

INTERVENTION

Participants completed a 12-week treatment that included group counseling, nicotine replacement therapy (NRT) and bupropion. Participants, independent of smoking status, were then assigned randomly to follow-up conditions: (i) standard treatment (ST; no further treatment); (ii) extended NRT (E-NRT; 40 weeks of nicotine gum availability); (iii) extended cognitive behavioral therapy (E-CBT; 11 cognitive behavioral sessions over a 40-week period); or (iv) E-CBT plus E-NRT (E-combined; 11 cognitive behavioral sessions plus 40 weeks nicotine gum availability).

MEASUREMENTS

Primary outcome variable was 7-day point prevalence cigarette abstinence verified biochemically at weeks 24, 52, 64 and 104.

FINDINGS

The most clinically important findings were significant main effects for treatment condition, time and the treatment x time interaction. The E-CBT condition produced high cigarette abstinence rates that were maintained throughout the 2-year study period [(week 24 (58%), 52 (55%), 64 (55%) and 104 (55%)], and was significantly more effective than E-NRT and ST across that period. No other treatment condition was significantly different to ST. No effects for gender were found.

CONCLUSIONS

Extended cognitive behavioral treatments can produce high and stable cigarette abstinence rates for both men and women. NRT does not add to the efficacy of extended CBT, and may hamper its efficacy. Research is needed to determine if these results can be replicated in a sample with a greater range of ages, and improved upon with the addition of medications other than NRT.

Relapse prevention interventions for smoking cessation

BACKGROUND

A number of treatments can help smokers make a successful quit attempt, but many initially successful quitters relapse over time. Several interventions were proposed to help prevent relapse.

OBJECTIVES

To assess whether specific interventions for relapse prevention reduce the proportion of recent quitters who return to smoking.

SEARCH STRATEGY

We searched the Cochrane Tobacco Addiction Group trials register in August 2008 for studies mentioning relapse prevention or maintenance in title, abstracts or keywords.

SELECTION CRITERIA

Randomized or quasi-randomized controlled trials of relapse prevention interventions with a minimum follow up of six months. We included smokers who quit on their own, or were undergoing enforced abstinence, or who were participating in treatment programmes. We included trials that compared relapse prevention interventions to a no intervention control, or that compared a cessation programme with additional relapse prevention components to a cessation programme alone.

DATA COLLECTION AND ANALYSIS

Studies were screened and data extracted by one author and checked by a second. Disagreements were resolved by discussion or referral to a third author.

MAIN RESULTS

Fifty-four studies met inclusion criteria, but were heterogeneous in terms of populations and interventions. We considered 36 studies that randomized abstainers separately from studies that randomized participants prior to their quit date.Looking at studies of behavioural interventions which randomised abstainers, we detected no benefit of brief and 'skills-based' relapse prevention methods for women who had quit smoking due to pregnancy, or for smokers undergoing a period of enforced abstinence during hospitalisation or military training. We also failed to detect significant effects of behavioural interventions in trials in unselected groups of smokers who had quit on their own or with a formal programme. Amongst trials randomising smokers prior to their quit date and evaluating the effect of additional relapse prevention components we also found no evidence of benefit of behavioural interventions in any subgroup. Overall, providing training in skills thought to be needed for relapse avoidance did not reduce relapse, but most studies did not use experimental designs best suited to the task, and had limited power to detect expected small differences between interventions. For pharmacological interventions, extended treatment with varenicline significantly reduced relapse in one trial (risk ratio 1.18, 95% confidence interval 1.03 to 1.36). Pooling of five studies of extended treatment with bupropion failed to detect a significant effect (risk ratio 1.17; 95% confidence interval 0.99 to 1.39). Two small trials of oral nicotine replacement treatment (NRT) failed to detect an effect but treatment compliance was low and in two other trials of oral NRT randomizing short-term abstainers there was a significant effect of intervention.

AUTHORS' CONCLUSIONS

At the moment there is insufficient evidence to support the use of any specific behavioural intervention for helping smokers who have successfully quit for a short time to avoid relapse. The verdict is strongest for interventions focusing on identifying and resolving tempting situations, as most studies were concerned with these. There is little research available regarding other behavioural approaches. Extended treatment with varenicline may prevent relapse. Extended treatment with bupropion is unlikely to have a clinically important effect. Studies of extended treatment with nicotine replacement are needed.

Behavioural and pharmacological mechanisms of bupropion's anti-smoking effects: recent preclinical and clinical insights

Ongoing studies continue to explore the behavioural and pharmacological effects of bupropion in smoking cessation studies and animal models of nicotine dependence. In the present review, the components of nicotine dependence that form the most likely targets of bupropion are identified within the context of an expanding preclinical and clinical literature regarding the anti-addictive properties of bupropion. Second, preclinical and clinical data that implicate specific pharmacological modes of action of bupropion in mediating the anti-smoking effects of the compound are discussed. Third, it is suggested that the unique mixed pharmacological profile of bupropion provides (1) attenuation of the multiple negative consequences of withdrawal via blockade of dopamine and noradrenaline reuptake; (2) replacement of the reward-facilitating and subjective effects of nicotine via blockade of dopaminergic reuptake; (3) attenuation of the rewarding effects of acute nicotine by nicotinic acetylcholine receptor blockade. The importance of species differences in bupropion metabolism in the interpretation of preclinical studies is highlighted. Finally, future studies are suggested to address identified gaps in the knowledge: most importantly, to provide stronger evidence for the role of noradrenaline reuptake inhibition in bupropion-induced attenuation of nicotine withdrawal. Future studies aimed at providing more evidence for the three-fold nature of the anti-smoking effects of bupropion are also suggested, along with the possibility of utilizing adjunct therapies to improve smoking cessation rates.

Extended cognitive behavior therapy for cigarette smoking cessation

PRIMARY AIM: Examine the effectiveness of extended cognitive behavior therapy (CBT) in promoting longer-term smoking abstinence.

DESIGN

Open-label treatment phase followed by extended treatment phase. Randomization conducted prior to entry into open-label treatment phase; analysis based on intention-to-treat to avoid threat of selection bias.

SETTING

Community smoking cessation clinic.

PARTICIPANTS

A total of 304 adult smokers (> or = 18 years of age; > or = 10 cigarettes/day).

INTERVENTION

Open-label (8 weeks): all participants received bupropion SR, nicotine patch, CBT. Extended treatment (12 weeks): participants received either CBT + voicemail monitoring and telephone counseling or telephone-based general support.

MEASUREMENTS

Seven-day point prevalence abstinence, expired-air carbon monoxide.

RESULTS

At week 20 follow-up, CBT produced a higher 7-day point prevalence abstinence rate: 45% versus 29%, P = 0.006; at 52 weeks the difference in abstinence rates (31% versus 27%) was not significant. History of depression was a moderator of treatment. Those with a positive history had a better treatment response at 20 weeks when assigned to the less intensive telephone support therapy (P < 0.05).

CONCLUSION

The superiority of CBT to 20 weeks suggests that continued emphasis on the development of cognitive and behavioral strategies for maintaining non-smoking during an extended treatment phase may help smokers to maintain abstinence in the longer term. At present, the minimum duration of therapy is unknown.

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.

Cue-induced reinstatement of nicotine-seeking behavior in rats: effect of bupropion, persistence over repeated tests, and its dependence on training dose

RATIONALE

The motivational effects of nicotine-associated cues have been demonstrated in animal studies. However, it is unknown whether the effectiveness of nicotine cues in reinstating nicotine-seeking varies with the extent of prior nicotine self-administration. In addition, the issue of whether bupropion (an FDA-approved smoking cessation medication) interferes with the conditioned incentive of nicotine cues remains to be addressed.

OBJECTIVE

This study determined the relationship of cue-reinstated nicotine-seeking and the levels of prior self-administration and examined the effect of bupropion on cue-induced reinstatement of nicotine-seeking in comparison with that on self-administration.

MATERIALS AND METHODS

Male Sprague-Dawley rats were trained in daily 1-h sessions to intravenously self-administer nicotine at different doses (0, 0.015, 0.03, 0.06 mg/kg/infusion) and to associate an auditory/visual cue with each nicotine delivery. After extinction, three reinstatement tests at 15 day intervals were conducted with re-presentation of the cue without nicotine delivery. In separate groups of rats trained with 0.03 mg/kg/infusion nicotine, bupropion (0, 10, 20, 40 mg/kg) was intraperitoneally administered to different groups before the reinstatement and in a within-subject design before the self-administration tests.

RESULTS

Cue-induced reinstatement of active lever responses was observed at all nicotine doses in the first reinstatement test, but at only the two highest doses during the second and third tests. The magnitude of reinstatement was positively correlated with level of prior responding for nicotine. Bupropion pretreatment decreased nicotine self-administration but enhanced cue-reinstated nicotine-seeking.

CONCLUSIONS

These results demonstrate the positive correlation of cue-reinstated nicotine-seeking with prior responding for nicotine self-administration and the persistence of the cue effect after taking higher doses of nicotine. The results of pharmacological tests suggest that although it is able to help achieve smoking cessation, bupropion may have little clinical benefit for the prevention of relapse associated with exposure to environmental smoking cues.

Nicotine replacement therapy for smoking cessation

BACKGROUND

The aim of nicotine replacement therapy (NRT) is temporarily to replace much of the nicotine from cigarettes to reduce motivation to smoke and nicotine withdrawal symptoms, thus easing the transition from cigarette smoking to complete abstinence.

OBJECTIVES

The aims of this review were:To determine the effect of NRT compared to placebo in aiding smoking cessation, and to consider whether there is a difference in effect for the different forms of NRT (chewing gum, transdermal patches, nasal spray, inhalers and tablets/lozenges) in achieving abstinence from cigarettes. To determine whether the effect is influenced by the dosage, form and timing of use of NRT; the intensity of additional advice and support offered to the smoker; or the clinical setting in which the smoker is recruited and treated. To determine whether combinations of NRT are more likely to lead to successful quitting than one type alone. To determine whether NRT is more or less likely to lead to successful quitting compared to other pharmacotherapies.

SEARCH STRATEGY

We searched the Cochrane Tobacco Addiction Group trials register for papers with 'nicotine' or 'NRT' in the title, abstract or keywords. Date of most recent search July 2007.

SELECTION CRITERIA

Randomized trials in which NRT was compared to placebo or to no treatment, or where different doses of NRT were compared. We excluded trials which did not report cessation rates, and those with follow up of less than six months.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate on the type of participants, the dose, duration and form of nicotine therapy, the outcome measures, method of randomization, and completeness of follow up. The main outcome measure was abstinence from smoking after at least six months of follow up. We used the most rigorous definition of abstinence for each trial, and biochemically validated rates if available. We calculated the risk ratio (RR) for each study. Where appropriate, we performed meta-analysis using a Mantel-Haenszel fixed-effect model.

MAIN RESULTS

We identified 132 trials; 111 with over 40,000 participants contributed to the primary comparison between any type of NRT and a placebo or non-NRT control group. The RR of abstinence for any form of NRT relative to control was 1.58 (95% confidence interval [CI]: 1.50 to 1.66). The pooled RR for each type were 1.43 (95% CI: 1.33 to 1.53, 53 trials) for nicotine gum; 1.66 (95% CI: 1.53 to 1.81, 41 trials) for nicotine patch; 1.90 (95% CI: 1.36 to 2.67, 4 trials) for nicotine inhaler; 2.00 (95% CI: 1.63 to 2.45, 6 trials) for oral tablets/lozenges; and 2.02 (95% CI: 1.49 to 3.73, 4 trials) for nicotine nasal spray. The effects were largely independent of the duration of therapy, the intensity of additional support provided or the setting in which the NRT was offered. The effect was similar in a small group of studies that aimed to assess use of NRT obtained without a prescription. In highly dependent smokers there was a significant benefit of 4 mg gum compared with 2 mg gum, but weaker evidence of a benefit from higher doses of patch. There was evidence that combining a nicotine patch with a rapid delivery form of NRT was more effective than a single type of NRT. Only one study directly compared NRT to another pharmacotherapy. In this study quit rates with nicotine patch were lower than with the antidepressant bupropion.

AUTHORS' CONCLUSIONS

All of the commercially available forms of NRT (gum, transdermal patch, nasal spray, inhaler and sublingual tablets/lozenges) can help people who make a quit attempt to increase their chances of successfully stopping smoking. NRTs increase the rate of quitting by 50-70%, regardless of setting. The effectiveness of NRT appears to be largely independent of the intensity of additional support provided to the individual. Provision of more intense levels of support, although beneficial in facilitating the likelihood of quitting, is not essential to the success of NRT.

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.

An intensive group therapy programme for smoking cessation using nicotine patch and internet mailing supports in a university setting

AIMS

Despite the growing literature on workplace tobacco control policies, very few studies have evaluated the role of smoking cessation programme as one of these policies in a university setting. We aimed to investigate the efficacy of intensive cessation programme delivered in a group format using nicotine patch therapy and internet mailing supports for our university employees.

METHODS

From January 2003, we conducted the group therapy programme for smoking cession seven times in Okayama University, Japan. This programme consisted of nicotine patch therapy and on-line supporting system. Smoking status was regularly assessed by direct interviews.

RESULTS

A total of 102 employees were enrolled in this programme, of whom 101 initiated their smoking cessation. One hundred participants (99%) received nicotine patch therapy, and its toxicities were generally mild. Of the 94 employees who could be follow-up for a year after the cessation, 50 (53%) sustained abstinence for a year. Multivariate analysis revealed that writing and sending e-mail messages within the first 1 week were significant factors affecting long-term cessation. The type of position also affected the cessation rate.

CONCLUSION

This study suggests that our programme in a university setting seems to be effective mainly because of peer-supports among the participants through regular face-to-face meetings and their own mailing supports.

Chronic bupropion attenuated the anhedonic component of nicotine withdrawal in rats via inhibition of dopamine reuptake in the nucleus accumbens shell

Bupropion, a dopamine reuptake inhibitor, is an effective therapy for smoking cessation, but the behavioral and neurochemical mechanisms mediating its antismoking properties are relatively unknown. To explore the hypothesis that bupropion ameliorates nicotine withdrawal partly by a dopamine-dependent mechanism, we investigated the effects of chronic bupropion on potassium-stimulated dopamine overflow in the nucleus accumbens shell in nicotine-withdrawing rats. We also assessed the effects of chronic bupropion on behavioral aspects of nicotine withdrawal measured by elevations in brain reward thresholds and somatic signs of withdrawal. Rats were treated with nicotine or saline for 7 days and then coadministration of bupropion or saline was initiated. After 14 days of coadministration of bupropion/saline and nicotine/saline, nicotine/saline administration was terminated, whereas bupropion/saline administration continued. These conditions mimic bupropion administration in human smokers. Cessation of nicotine administration in non-bupropion-treated rats elevated reward thresholds reflecting a reward deficit, increased somatic signs and diminished potassium-evoked dopamine overflow in the nucleus accumbens shell. Chronic bupropion lowered reward thresholds and increased potassium-evoked dopamine release regardless of previous nicotine exposure, possibly by inhibition of dopamine reuptake, and thus attenuated the anhedonic and neurochemical effects of nicotine withdrawal. Chronic bupropion blocked withdrawal-associated increased somatic signs. Finally, acute experimenter-administered nicotine enhanced brain reward function equally in all groups, indicating that bupropion does not alter the reward-facilitating effects of experimenter-administered nicotine. In conclusion, the bupropion-induced increase in extracellular dopamine in the nucleus accumbens shell may ameliorate the anhedonia associated with nicotine withdrawal, which in turn may facilitate smoking cessation.

Smoking cessation interventions in clinical practice

OBJECTIVES

Physicians are in a unique position to advise smokers to quit by integrating the various aspects of nicotine dependence. This review provides an overview of interventions for smokers presenting in a clinical setting.

RESULTS

Strategies used for smoking cessation counselling differ according to patient's readiness to quit. For smokers who do not intend to quit smoking, physicians should inform and sensitise them about tobacco use and cessation. For smokers who are dissonant, physicians should use motivational strategies, such as discussing barriers to cessation and their solutions. For smokers ready to quit, the physician should show strong support, help set a quit date, prescribe pharmaceutical therapies for nicotine dependence, such as nicotine replacement therapy (i.e., gum, transdermal patch, nasal spray, mouth inhaler, lozenges, micro and sublingual tablets) and/or bupropion (atypical antidepressant thought to work by blocking neural reuptake of dopamine and/or nor epinephrine), with instructions for use, and suggest behavioural strategies to prevent relapse. The efficacy of all of these pharmacotherapies is comparable, roughly doubling cessation rates over control conditions. Varenicline is a promising new effective drug recently approved by many health authorities.

CONCLUSION

Physician counselling and pharmacotherapeutic interventions for smoking cessation are among the most cost-effective clinical interventions.

A randomized trial of bupropion and/or nicotine gum as maintenance treatment for preventing smoking relapse

AIM

To investigate the efficacy of maintenance treatment with bupropion and/or nicotine gum for reducing smoking relapse.

DESIGN, SETTING AND PARTICIPANTS

A 48-week study was conducted at a university-based smoking cessation clinic between February 2001 and October 2005. A total of 588 smokers received bupropion and nicotine patch in 8 weeks of open-label treatment (OLT); 289 abstainers during the last 4 weeks of OLT were randomized in double-blind placebo-controlled fashion to one of four arms for 16 weeks of maintenance treatment (MT) followed by 24 weeks of non-treatment follow-up (NTFU).

INTERVENTION

Bupropion (300 mg/day) and 2 mg nicotine gum, used alone or combined, and comparable placebo pill and placebo gum. Behavioral counseling at all visits.

OUTCOME

Time to relapse (TTR) from randomization. Relapse is defined as the first 7 consecutive days of smoking. Abstinence verified by carbon monoxide <or= 8 parts per million.

FINDINGS

TTR was longer with extended active treatments compared to placebo (median days to relapse: bupropion + placebo = 136, nicotine + placebo = 98, bupropion + nicotine = 90, double placebo = 71). Hazard ratios (HR) for relapse were statistically significant for bupropion + placebo versus double placebo during MT (HR = 0.59, 95% CI = 0.37-0.92) and to the end of NTFU (HR = 0.66, 95% CI = 0.42-0.96). However, bupropion's advantage dissipated upon stopping the drug. Gum use was low, preventing a valid assessment; but analysis restricted to gum users suggested a weak effect of extended nicotine gum.

CONCLUSION

Maintenance treatment with bupropion exerted a modest benefit for preventing smoking relapse; the optimum duration of bupropion treatment was unclear. Further research is needed to ascertain the merits of extended use of nicotine gum, other nicotine replacement agents and other treatments known to aid smokers for preventing relapse once abstinence is achieved.

Discovery of a novel nicotinic receptor antagonist for the treatment of nicotine addiction: 1-(3-Picolinium)-12-triethylammonium-dodecane dibromide (TMPD)

Limitations in efficacy and high relapse rates of currently available smoking cessation agents reveal the need for more efficacious pharmacotherapies. One strategy is to develop subtype-selective nicotinic receptor (nAChR) antagonists that inhibit nicotine-evoked dopamine (DA) release, the primary neurotransmitter involved in nicotine reward. Simple alkylation of the pyridino N-atom converts nicotine from a potent agonist into a potent antagonist. The classical antagonists, hexamethonium and decamethonium, differentiate between peripheral nAChR subtypes. Using a similar approach, we interconnected varying quaternary ammonium moieties with a lipophilic linker to provide N,N'-bis-nicotinium analogs, affording a lead compound, N,N'-dodecyl-1,12-diyl-bis-3-picolinium dibromide (bPiDDB), which inhibited nicotine-evoked DA release and decreased nicotine self-administration. The current work describes a novel compound, 1-(3-picolinium)-12-triethylammonium-dodecane dibromide (TMPD), a hybrid of bPiDDB and decamethonium. TMPD completely inhibited (IC(50)=500 nM) nicotine-evoked DA release from superfused rat striatal slices, suggesting that TMPD acts as a nAChR antagonist at more than one subtype. TMPD (1 microM) inhibited the response to acetylcholine at alpha3beta4, alpha4beta4, alpha4beta2, and alpha1beta1varepsilondelta receptors expressed in Xenopus oocytes. TMPD had a 2-fold higher affinity than choline for the blood-brain barrier choline transporter, suggesting brain bioavailability. TMPD did not inhibit hyperactivity in nicotine sensitized rats, but significantly and specifically decreased nicotine self-administration. Together, the results suggest that TMPD may have the ability to reduce the rewarding effect of nicotine with minimal side effects, a pharmacological profile indicative of potential clinical utility for the treatment of tobacco dependence.

Animal models and treatments for addiction and depression co-morbidity

The high rates of co-morbidity of drug addiction with depression may be attributable to shared neurobiology. Here, we discuss shared neurobiological substrates in drug withdrawal and depression, with an emphasis on changes in brain reward circuitry that may underlie anhedonia, a core symptom of depression and drug withdrawal. We explored experimentally whether clinical antidepressant medications or other treatments would reverse the anhedonia observed in rats undergoing spontaneous nicotine or amphetamine withdrawal, defined operationally as elevated brain reward thresholds. The co-administration of selective serotonin reuptake inhibitors with a serotonin-1A receptor antagonist, or the tricyclic antidepressant desipramine, or the atypical antidepressant bupropion ameliorated nicotine or amphetamine withdrawal in rats. Thus, increases in monoaminergic neurotransmission, or neuroadaptations induced by increased monoaminergic neurotransmission, ameliorated depression-like aspects of drug withdrawal. Further, chronic pretreatment with the atypical antipsychotic clozapine, that has some efficacy in the treatment of the depression-like symptoms of schizophrenia, attenuated nicotine and amphetamine withdrawal. Finally, a metabotropic glutamate 2/3 receptor antagonist reversed threshold elevations associated with nicotine withdrawal. The effects of these pharmacological manipulations are consistent with the altered neurobiology observed in drug withdrawal and depression. Thus, these data support the hypothesis of common substrates mediating the depressive symptoms of drug withdrawal and those seen in psychiatric patients. Accordingly, the anhedonic state associated with drug withdrawal can be used to study the neurobiology of anhedonia, and thus contribute to the identification of novel targets for the treatment of depression-like symptoms seen in various psychiatric and neurological disorders.

Randomized comparison of a nicotine inhaler and bupropion for smoking cessation and relapse prevention

OBJECTIVE

To compare the combination of a nicotine inhaler and bupropion to either treatment alone for initiating smoking abstinence and relapse prevention.

METHODS

Smokers were randomized to receive a nicotine inhaler, bupropion, or both for 3 months. At 3 months, smoking-abstinent study participants were randomized to their initial medications or placebo. Participants who were smoking at 3 months were randomized to an alternative treatment regimen or placebo. This study was conducted from July 2001 to January 2003.

RESULTS

A total of 1700 smokers were randomized to treatment (phase 1) for 3 months. Among the 941 study participants eligible for randomization to the phase 2 trial, 837 continued in the study. For the phase 2 trial, 405 smoking-abstinent participants were randomized to relapse prevention for 9 additional months, and 432 smokers were randomized to re-treatment for an additional 3 months. At the end of the initial 3 months of treatment (phase 1), 82 (14%) of 566, 145 (26%) of 567, and 194 (34%) of 567 study participants receiving a nicotine inhaler, bupropion, or both, respectively, were abstinent from smoking. Of the 405 smoking-abstinent participants at the end of 3 months, the bupropion group had more smokers than the placebo group (mean No. of smokers, 1.5 vs 1.1; P < .001), and the nicotine inhaler group had higher smoking abstinence rates at 12 months than the placebo group. Those receiving combination therapy had reduced rates of relapse to smoking for the first 3 months of relapse prevention, but this difference disappeared after the initial 3 months. Of the 432 study participants who were smoking at the end of 3 months and who received an alternative treatment regimen, the 223 smokers initially assigned to a nicotine inhaler were more likely to stop smoking at 6 months if they were re-treated with bupropion instead of placebo (8 [7%] of 111 vs 0 [0%] of 112; P = .003), and the 209 smokers initially treated with bupropion and re-treated with a nicotine inhaler did not have significantly higher smoking abstinence rates (6 [6%] of 104 vs 3 [3%] of 105; P = -.50).

CONCLUSION

Combined therapy with a nicotine inhaler and bupropion increased smoking abstinence rates. Continuation of the initial combination therapy does not appear to prevent relapse to smoking. Timing of re-treatment and alternative approaches to relapse prevention should be further examined.

High-dose transdermal nicotine and naltrexone: effects on nicotine withdrawal, urges, smoking, and effects of smoking

Although treatment with transdermal nicotine replacement (TNR) has improved smoking abstinence rates, higher doses of TNR could improve effects on urge to smoke, nicotine withdrawal, and reinforcement from smoking, and naltrexone might further reduce reinforcement and urges. A laboratory investigation with 134 smokers using a 3 x 2 parallel-group design evaluated the effects of TNR (42-mg, 21-mg, or 0-mg patch) as crossed with a single dose of naltrexone (50 mg) versus placebo on urge to smoke, withdrawal, and responses to an opportunity to smoke (intake, subjective effects) after 10 hr of deprivation. Urge and withdrawal were assessed both prior to and after cigarette cue exposure. Only 42 mg TNR, not 21 mg, prevented urge to smoke, heart rate change, and cue-elicited increase in withdrawal. Both 21 and 42 mg TNR blocked cue-elicited drop in heart rate and arterial pressure. Naltrexone reduced cue-elicited withdrawal symptoms but not urges to smoke or deprivation-induced withdrawal prior to cue exposure. Neither medication significantly affected carbon monoxide intake or subjective effects of smoking except that 42 mg TNR resulted in lower subjective physiological activation. No interaction effects were found, and no results differed by gender. Results suggest that starting smokers with 42 mg TNR may increase comfort during initial abstinence, but limited support is seen for naltrexone during smoking abstinence.

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.

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.