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The Cochrane Database of Systematic... Oct 2015Use of smokeless tobacco (ST) can lead to tobacco dependence and long-term use can lead to health problems including periodontal disease, cancer, and cerebrovascular and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Use of smokeless tobacco (ST) can lead to tobacco dependence and long-term use can lead to health problems including periodontal disease, cancer, and cerebrovascular and cardiovascular disease.
OBJECTIVES
To assess the effects of behavioural and pharmacologic interventions for the treatment of ST use.
SEARCH METHODS
We searched the Cochrane Tobacco Addiction Group specialised register in June 2015.
SELECTION CRITERIA
Randomized trials of behavioural or pharmacological interventions to help users of ST to quit with follow-up of at least six months.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures as expected by the Cochrane Collaboration. We summarised outcomes as risk ratios (RRs). For subgroups of trials with similar types of intervention and without substantial statistical heterogeneity, we estimated pooled effects using a Mantel-Haenszel fixed-effect method.
MAIN RESULTS
We identified 34 trials that met the inclusion criteria, of which nine were new for this update, representing over 16,000 participants. There was moderate quality evidence from two studies suggesting that varenicline increases ST abstinence rates (risk ratio [RR] 1.34, 95% confidence interval (CI) 1.08 to 1.68, 507 participants). Pooled results from two trials of bupropion did not detect a benefit of treatment at six months or longer (RR 0.89, 95% CI 0.54 to 1.44, 293 participants) but the confidence interval was wide. Neither nicotine patch (five trials, RR 1.13, 95% CI 0.93 to 1.37, 1083 participants) nor nicotine gum (two trials, RR 0.99, 95% CI 0.68 to 1.43, 310 participants) increased abstinence. Pooling five studies of nicotine lozenges did increase tobacco abstinence (RR 1.36, 95% CI 1.17 to 1.59, 1529 participants) but confidence in this estimate is low as the result is sensitive to the exclusion of three trials which did not use a placebo control.Statistical heterogeneity was evident among the 17 trials of behavioural interventions: eight of them reported statistically and clinically significant benefits; six suggested benefit but with wide CIs and no statistical significance; and three had similar intervention and control quit rates and relatively narrow CIs. Heterogeneity was not explained by study design (individual or cluster randomization), whether participants were selected for interest in quitting, or specific intervention components. In a post hoc subgroup analysis, trials of behavioural interventions incorporating telephone support, with or without oral examination and feedback, were associated with larger effect sizes, but oral examination and feedback alone were not associated with benefit.In one trial an interactive website increased abstinence more than a static website. One trial comparing immediate cessation using nicotine patch versus a reduction approach using either nicotine lozenge or brand switching showed greater success for the abrupt cessation group.
AUTHORS' CONCLUSIONS
Varenicline, nicotine lozenges and behavioural interventions may help ST users to quit. Confidence in results for nicotine lozenges is limited. Confidence in the size of effect from behavioural interventions is limited because the components of behavioural interventions that contribute to their impact are not clear.
Topics: Benzazepines; Bupropion; Chewing Gum; Counseling; Humans; Nicotine; Nicotinic Agonists; Quinoxalines; Randomized Controlled Trials as Topic; Tobacco Use Cessation; Tobacco, Smokeless; Varenicline
PubMed: 26501380
DOI: 10.1002/14651858.CD004306.pub5 -
International Journal of Environmental... Feb 2023Although varenicline has been used for alcohol dependence (AD) treatment, its efficacy for this condition remains controversial. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Although varenicline has been used for alcohol dependence (AD) treatment, its efficacy for this condition remains controversial.
AIMS
This systematic review and meta-analysis of randomized controlled trials (RCTs) assesses the efficacy and safety of varenicline in patients with AD.
METHODS
PubMed, Cochrane Library, ScienceDirect, Web of Science, and ThaiLis were systematically searched. RCTs investigating the efficacy and safety of varenicline in patients with AD were included. Study selection, data extraction, and quality assessment were independently performed by two authors. The Jadad score and Cochrane risk of bias were used to assess the quality of the included studies. Heterogeneity was assessed using I and chi-squared tests.
RESULTS
Twenty-two high-quality RCTs on 1421 participants were included. Varenicline significantly reduced alcohol-related outcomes compared with placebo based on percentage of abstinent days (standardized mean difference [SMD] 4.20 days; 95% confidence interval [CI]: 0.21, 8.19; = 0.04), drinks per day (SMD -0.23 drinks; 95% CI: -0.43, -0.04; = 0.02), drinks per drinking day (SMD -0.24 drinks; 95% CI: -0.44, -0.05; = 0.01), craving assessed using the Penn alcohol craving scale (SMD -0.35; 95% CI: -0.59, -0.12; = 0.003), and craving assessed using the alcohol urge questionnaire (SMD -1.41; 95% CI: -2.12, -0.71; < 0.0001). However, there were no significant effects on abstinence rate, percentage of drinking days, percentage of heavy drinking days, alcohol intoxication, or drug compliance. Serious side effects were not observed in the varenicline or placebo groups.
CONCLUSION
Our results indicated that AD patients treated with varenicline showed improvement in percentage of very heavy drinking days, percentage of abstinent days, drinks per day, drinks per drinking day, and craving. However, well-designed RCTs with a large sample size and long duration on varenicline treatment in AD remain warranted to confirm our findings.
Topics: Humans; Alcoholic Intoxication; Alcoholism; Craving; Ethanol; Varenicline; Randomized Controlled Trials as Topic
PubMed: 36901103
DOI: 10.3390/ijerph20054091 -
The Cochrane Database of Systematic... Sep 2021Electronic cigarettes (ECs) are handheld electronic vaping devices which produce an aerosol formed by heating an e-liquid. Some people who smoke use ECs to stop or... (Review)
Review
BACKGROUND
Electronic cigarettes (ECs) are handheld electronic vaping devices which produce an aerosol formed by heating an e-liquid. Some people who smoke use ECs to stop or reduce smoking, but some organizations, advocacy groups and policymakers have discouraged this, citing lack of evidence of efficacy and safety. People who smoke, healthcare providers and regulators want to know if ECs can help people quit and if they are safe to use for this purpose. This is an update conducted as part of a living systematic review.
OBJECTIVES
To examine the effectiveness, tolerability, and safety of using electronic cigarettes (ECs) to help people who smoke tobacco achieve long-term smoking abstinence.
SEARCH METHODS
We searched the Cochrane Tobacco Addiction Group's Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO to 1 May 2021, and reference-checked and contacted study authors. We screened abstracts from the Society for Research on Nicotine and Tobacco (SRNT) 2021 Annual Meeting. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and randomized cross-over trials, in which people who smoke were randomized to an EC or control condition. We also included uncontrolled intervention studies in which all participants received an EC intervention. Studies had to report abstinence from cigarettes at six months or longer or data on safety markers at one week or longer, or both.
DATA COLLECTION AND ANALYSIS
We followed standard Cochrane methods for screening and data extraction. Our primary outcome measures were abstinence from smoking after at least six months follow-up, adverse events (AEs), and serious adverse events (SAEs). Secondary outcomes included the proportion of people still using study product (EC or pharmacotherapy) at six or more months after randomization or starting EC use, changes in carbon monoxide (CO), blood pressure (BP), heart rate, arterial oxygen saturation, lung function, and levels of carcinogens or toxicants or both. We used a fixed-effect Mantel-Haenszel model to calculate risk ratios (RRs) with a 95% confidence interval (CI) for dichotomous outcomes. For continuous outcomes, we calculated mean differences. Where appropriate, we pooled data in meta-analyses.
MAIN RESULTS
We included 61 completed studies, representing 16,759 participants, of which 34 were RCTs. Five of the 61 included studies were new to this review update. Of the included studies, we rated seven (all contributing to our main comparisons) at low risk of bias overall, 42 at high risk overall (including all non-randomized studies), and the remainder at unclear risk. There was moderate-certainty evidence, limited by imprecision, that quit rates were higher in people randomized to nicotine EC than in those randomized to nicotine replacement therapy (NRT) (risk ratio (RR) 1.53, 95% confidence interval (CI) 1.21 to 1.93; I = 0%; 4 studies, 1924 participants). In absolute terms, this might translate to an additional three quitters per 100 (95% CI 1 to 6). There was low-certainty evidence (limited by very serious imprecision) that the rate of occurrence of AEs was similar (RR 0.98, 95% CI 0.80 to 1.19; I = 0%; 2 studies, 485 participants). SAEs were rare, but there was insufficient evidence to determine whether rates differed between groups due to very serious imprecision (RR 1.30, 95% CI 0.89 to 1.90: I = 0; 4 studies, 1424 participants). There was moderate-certainty evidence, again limited by imprecision, that quit rates were higher in people randomized to nicotine EC than to non-nicotine EC (RR 1.94, 95% CI 1.21 to 3.13; I = 0%; 5 studies, 1447 participants). In absolute terms, this might lead to an additional seven quitters per 100 (95% CI 2 to 16). There was moderate-certainty evidence of no difference in the rate of AEs between these groups (RR 1.01, 95% CI 0.91 to 1.11; I = 0%; 3 studies, 601 participants). There was insufficient evidence to determine whether rates of SAEs differed between groups, due to very serious imprecision (RR 1.06, 95% CI 0.47 to 2.38; I = 0; 5 studies, 792 participants). Compared to behavioural support only/no support, quit rates were higher for participants randomized to nicotine EC (RR 2.61, 95% CI 1.44 to 4.74; I = 0%; 6 studies, 2886 participants). In absolute terms this represents an additional six quitters per 100 (95% CI 2 to 15). However, this finding was of very low certainty, due to issues with imprecision and risk of bias. There was some evidence that non-serious AEs were more common in people randomized to nicotine EC (RR 1.22, 95% CI 1.12 to 1.32; I = 41%, low certainty; 4 studies, 765 participants), and again, insufficient evidence to determine whether rates of SAEs differed between groups (RR 1.51, 95% CI 0.70 to 3.24; I = 0%; 7 studies, 1303 participants). Data from non-randomized studies were consistent with RCT data. The most commonly reported AEs were throat/mouth irritation, headache, cough, and nausea, which tended to dissipate with continued use. Very few studies reported data on other outcomes or comparisons, hence evidence for these is limited, with CIs often encompassing clinically significant harm and benefit.
AUTHORS' CONCLUSIONS
There is moderate-certainty evidence that ECs with nicotine increase quit rates compared to NRT and compared to ECs without nicotine. Evidence comparing nicotine EC with usual care/no treatment also suggests benefit, but is less certain. More studies are needed to confirm the effect size. Confidence intervals were for the most part wide for data on AEs, SAEs and other safety markers, with no difference in AEs between nicotine and non-nicotine ECs. Overall incidence of SAEs was low across all study arms. We did not detect evidence of harm from nicotine EC, but longest follow-up was two years and the number of studies was small. The main limitation of the evidence base remains imprecision due to the small number of RCTs, often with low event rates, but further RCTs are underway. To ensure the review continues to provide up-to-date information to decision-makers, this review is now a living systematic review. We run searches monthly, with the review updated when relevant new evidence becomes available. Please refer to the Cochrane Database of Systematic Reviews for the review's current status.
Topics: Electronic Nicotine Delivery Systems; Humans; Nicotinic Agonists; Smoking Cessation; Systematic Reviews as Topic; Tobacco Use Cessation Devices
PubMed: 34519354
DOI: 10.1002/14651858.CD010216.pub6 -
Annals of Medicine Sep 2012This review compared the effect of high-dose nicotine replacement therapy (NRT) and combinations of NRT for increasing smoking abstinence rates compared to standard-dose... (Comparative Study)
Comparative Study Meta-Analysis Review
Comparisons of high-dose and combination nicotine replacement therapy, varenicline, and bupropion for smoking cessation: a systematic review and multiple treatment meta-analysis.
AIM
This review compared the effect of high-dose nicotine replacement therapy (NRT) and combinations of NRT for increasing smoking abstinence rates compared to standard-dose NRT patch, varenicline, and bupropion on smoking abstinence.
METHODS
Ten electronic databases were searched (up to January 2012) for randomized controlled trials (RCT) of standard-dose (≤ 22 mg) or high-dose nicotine patch therapy (> 22 mg), combination NRT (e.g. nicotine patch + nicotine inhaler), bupropion, and varenicline. Analysis consisted of random-effects pairwise meta-analysis and a Bayesian multiple treatment comparison (MTC).
RESULTS
We identified 146 RCTs (65 standard-doses of the nicotine patch (≤ 22 mg); 6 high-dose NRT patch (> 22 mg); 5 high versus standard-dose NRT patch; 5 combination NRT versus inert controls; 6 combination versus single NRT patch; 48 bupropion; and 11 varenicline). The MTC found that all therapies offered treatment benefits at most time points over controls. Combination NRT and higher-dose NRT did not demonstrate consistent effects over other interventions. With the exception of varenicline, the benefits of treatments over standard-dose NRT were not retained in the long term.
CONCLUSIONS
All pharmacologic treatments were significantly more effective than inert controls. Varenicline was the only treatment demonstrating effects over other options. These results should be considered in the development of clinical practice guidelines.
Topics: Benzazepines; Bupropion; Databases, Bibliographic; Dose-Response Relationship, Drug; Drug Therapy, Combination; Humans; Nicotinic Antagonists; Quinoxalines; Smoking Cessation; Tobacco Use Cessation Devices; Varenicline
PubMed: 22860882
DOI: 10.3109/07853890.2012.705016 -
BMJ Open Jan 2016To establish which non-psychotropic medications have been assessed in relation to risk of suicide or attempted suicide in observational studies, document reported... (Review)
Review
OBJECTIVES
To establish which non-psychotropic medications have been assessed in relation to risk of suicide or attempted suicide in observational studies, document reported associations and consider study strengths and limitations.
DESIGN
Systematic review.
METHODS
Four databases (Embase, Medline, PsycINFO and International Pharmaceutical Abstracts) were searched from 1990 to June 2014, and reference lists of included articles were hand-searched. Case-control, cohort and case only studies which reported suicide or attempted suicide in association with any non-psychotropic medication were included.
OUTCOME MEASURES
The outcomes eligible for inclusion were suicide and attempted suicide, as defined by the authors of the included study.
RESULTS
Of 11,792 retrieved articles, 19 were eligible for inclusion. Five studies considered cardiovascular medication and antiepileptics; two considered leukotriene receptor antagonists, isotretinoin and corticosteroids; one assessed antibiotics and another assessed varenicline. An additional study compared multiple medications prescribed to suicide cases versus controls. There was marked heterogeneity in study design, outcome and exposure classification, and control for confounding factors; particularly comorbid mental and physical illness. No increased risk was associated with cardiovascular medications, but associations with other medications remained inconclusive and meta-analysis was inappropriate due to study heterogeneity.
CONCLUSIONS
Whether non-psychotropic medications are associated with increased risk of suicide or attempted suicide remains largely unknown. Robust identification of suicide outcomes and control of comorbidities could improve quantification of risk associated with non-psychotropic medication, beyond that conferred by underlying physical and mental illnesses.
Topics: Adrenal Cortex Hormones; Anti-Bacterial Agents; Anticonvulsants; Cardiovascular Agents; Humans; Isotretinoin; Leukotriene Antagonists; Observational Studies as Topic; Prescription Drugs; Risk; Risk Factors; Suicide; Suicide, Attempted; Varenicline
PubMed: 26769782
DOI: 10.1136/bmjopen-2015-009074 -
The Cochrane Database of Systematic... Aug 2016Smoking cessation is the most important treatment for smokers with chronic obstructive pulmonary disease (COPD), but little is known about the effectiveness of different... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Smoking cessation is the most important treatment for smokers with chronic obstructive pulmonary disease (COPD), but little is known about the effectiveness of different smoking cessation interventions for this particular group of smokers.
OBJECTIVES
To evaluate the effectiveness of behavioural or pharmacological smoking cessation interventions, or both, in smokers with COPD.
SEARCH METHODS
We searched all records in the Cochrane Airways Group Specialised Register of Trials. In addition to this electronic search, we searched clinical trial registries for planned, ongoing, and unpublished trials. We searched all databases from their inception. We checked the reference lists of all included studies and of other systematic reviews in relevant topic areas. We searched for errata or retractions from eligible trials on PubMed. We conducted our most recent search in March 2016.
SELECTION CRITERIA
We included randomised controlled trials assessing the effectiveness of any behavioural or pharmacological treatment, or both, in smokers with COPD reporting at least six months of follow-up abstinence rates.
DATA COLLECTION AND ANALYSIS
Two review authors independently extracted the data and performed the methodological quality assessment for each study. We resolved any disagreements by consensus.
MAIN RESULTS
We included 16 studies (involving 13,123 participants) in this systematic review, two of which were of high quality. These two studies showed that nicotine sublingual tablet and varenicline increased the quit rate over placebo (risk ratio (RR) 2.60 (95% confidence interval (CI) 1.29 to 5.24) and RR 3.34 (95% CI 1.88 to 5.92)). Pooled results of two studies also showed a positive effect of bupropion compared with placebo (RR 2.03 (95% CI 1.26 to 3.28)). When pooling these four studies, we found high-quality evidence for the effectiveness of pharmacotherapy plus high-intensity behavioural treatment compared with placebo plus high-intensity behavioural treatment (RR 2.53 (95% CI 1.83 to 3.50)). Furthermore, we found some evidence that high-intensity behavioural treatment increased abstinence rates when compared with usual care (RR 25.38 (95% CI 8.03 to 80.22)) or low-intensity behavioural treatment (RR 2.18 (95% CI 1.05 to 4.49)). Finally, the results showed effectiveness of various combinations of psychosocial and pharmacological interventions.
AUTHORS' CONCLUSIONS
We found high-quality evidence in a meta-analysis including four (1,540 participants) of the 16 included studies that a combination of behavioural treatment and pharmacotherapy is effective in helping smokers with COPD to quit smoking. Furthermore, we conclude that there is no convincing evidence for preferring any particular form of behavioural or pharmacological treatment.
Topics: Adult; Behavior Therapy; Bupropion; Combined Modality Therapy; Female; Humans; Male; Nicotine; Nicotinic Agonists; Pulmonary Disease, Chronic Obstructive; Randomized Controlled Trials as Topic; Smoking Cessation; Varenicline
PubMed: 27545342
DOI: 10.1002/14651858.CD010744.pub2 -
International Journal of Environmental... Dec 2022The detrimental impact of smoking on health and wellbeing are irrefutable. Additionally, smoking is associated with the development of cancer, a reduction treatment... (Review)
Review
The detrimental impact of smoking on health and wellbeing are irrefutable. Additionally, smoking is associated with the development of cancer, a reduction treatment outcomes and poorer health outcomes. Nevertheless, a significant number of people continue to smoke following a cancer diagnosis. Little is understood of the smoking cessation services provided to smokers with cancer or their engagement with them. This systematic review aimed to identify existing smoking cessation interventions for this cohort diagnosed with breast, head and neck, lung and cervical cancers (linked to risk). Systematic searches of Pubmed, Embase, Psych Info and CINAHL from 1 January 2015 to 15 December 2020 were conducted. Included studies examined the characteristics of smoking cessation interventions and impact on referrals and quit attempts. The impact on healthcare professionals was included if reported. Included studies were restricted to adults with a cancer diagnosis and published in English. No restriction was placed on study designs, and narrative data synthesis was conducted due to heterogeneity. A review protocol was registered on PROSPERO CRD 42020214204, and reporting adheres to PRISMA reporting guidelines. Data were screened, extracted in duplicate and an assessment of the quality of evidence undertaken using Mixed Methods Assessment Tool. 23 studies met the inclusion criteria, representing USA, Canada, England, Lebanon, Australia and including randomized controlled trials (9), observational studies (10), quality improvement (3), and one qualitative study. Hospital and cancer clinics [including a dental clinic] were the settings for all studies. 43% (10/23) of studies reported interventions for smokers diagnosed with head and neck cancer, 13% (3/23) for smokers diagnosed with lung cancer, one study provides evidence for breast cancer, and the remaining nine studies (39%) report on multiple cancers including the ones specified in this review. Methodological quality was variable. There were limited data to identify one optimal intervention for this cohort. Key elements included the timing and frequency of quit conversations, use of electronic records, pharmacotherapy including extended use of varenicline, increased counselling sessions and a service embedded in oncology departments. More studies are required to ensure tailored smoking cessation pathways are co-developed for smokers with a diagnosis of cancer to support this population.
Topics: Adult; Humans; Smoking Cessation; Smokers; Inventions; Head and Neck Neoplasms; Delivery of Health Care
PubMed: 36554894
DOI: 10.3390/ijerph192417010 -
Addiction (Abingdon, England) Apr 2022To determine how varenicline, bupropion, nicotine replacement therapy (NRT) and electronic cigarettes compare with respect to their clinical effectiveness and safety. (Meta-Analysis)
Meta-Analysis Review
Comparative clinical effectiveness and safety of tobacco cessation pharmacotherapies and electronic cigarettes: a systematic review and network meta-analysis of randomized controlled trials.
AIM
To determine how varenicline, bupropion, nicotine replacement therapy (NRT) and electronic cigarettes compare with respect to their clinical effectiveness and safety.
METHOD
Systematic reviews and Bayesian network meta-analyses of randomized controlled trials, in any setting, of varenicline, bupropion, NRT and e-cigarettes (in high, standard and low doses, alone or in combination) in adult smokers and smokeless tobacco users with follow-up duration of 24 weeks or greater (effectiveness) or any duration (safety). Nine databases were searched until 19 February 2019. Primary outcomes were sustained tobacco abstinence and serious adverse events (SAEs). We estimated odds ratios (ORs) and treatment rankings and conducted meta-regression to explore covariates.
RESULTS
We identified 363 trials for effectiveness and 355 for safety. Most monotherapies and combination therapies were more effective than placebo at helping participants to achieve sustained abstinence; the most effective of these, estimated with some imprecision, were varenicline standard [OR = 2.83, 95% credible interval (CrI) = 2.34-3.39] and varenicline standard + NRT standard (OR = 5.75, 95% CrI = 2.27-14.88). Estimates were higher in smokers receiving counselling than in those without and in studies with higher baseline nicotine dependence scores than in those with lower scores. Varenicline standard + NRT standard showed a high probability of being ranked best or second-best. For safety, only bupropion at standard dose increased the odds of experiencing SAEs compared with placebo (OR = 1.27, 95% CrI = 1.04-1.58), and we found no evidence of effect modification.
CONCLUSIONS
Most tobacco cessation monotherapies and combination therapies are more effective than placebo at helping participants to achieve sustained abstinence, with varenicline appearing to be most effective based on current evidence. There does not appear to be strong evidence of associations between most tobacco cessation pharmacotherapies and adverse events; however, the data are limited and there is a need for improved reporting of safety data.
Topics: Adult; Bayes Theorem; Bupropion; Electronic Nicotine Delivery Systems; Humans; Network Meta-Analysis; Randomized Controlled Trials as Topic; Smoking Cessation; Tobacco Use Cessation; Tobacco Use Cessation Devices; Treatment Outcome; Varenicline
PubMed: 34636108
DOI: 10.1111/add.15675 -
The Cochrane Database of Systematic... Apr 2020Whilst the pharmacological profiles and mechanisms of antidepressants are varied, there are common reasons why they might help people to stop smoking tobacco. Firstly,... (Meta-Analysis)
Meta-Analysis
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; I = 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; I = 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; I = 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; I = 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; I = 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; I = 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; I = 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; I = 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; I = 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; I = 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.
Topics: Anti-Anxiety Agents; Antidepressive Agents; Bupropion; Humans; Nortriptyline; Randomized Controlled Trials as Topic; Selective Serotonin Reuptake Inhibitors; Smoking; Smoking Cessation; Tobacco Use Cessation Devices; Varenicline
PubMed: 32319681
DOI: 10.1002/14651858.CD000031.pub5 -
Addiction (Abingdon, England) Apr 2016To assess the efficacy and tolerability of adjunctive pharmacotherapy for smoking cessation in adults with serious mental illness (SMI) by means of a systematic review... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND AND AIMS
To assess the efficacy and tolerability of adjunctive pharmacotherapy for smoking cessation in adults with serious mental illness (SMI) by means of a systematic review and network meta-analysis.
METHOD
We searched Embase, Medline, PsychINFO and the Cochrane Central Register of Controlled Trials from database inception to 1 December 2014 for randomized controlled trials (RCTs) published in English. We included all studies of smokers with SMI (including schizophrenia, schizoaffective disorder, bipolar disorder, delusional disorder and depressive psychoses) who were motivated to quit smoking. Pharmacotherapies included nicotine replacement therapy (NRT), bupropion and varenicline delivered as monotherapy or in combination compared with each other or placebo. The efficacy outcome was self-reported sustained smoking cessation, verified biochemically at the longest reported time-point. The tolerability outcome was number of patients discontinuing the trial due to any adverse event.
RESULTS
Seventeen study reports were included, which represented 14 individual RCTs. No trials were found in patients with depressive psychoses, delusional disorder or that compared NRT monotherapy with placebo. A total of 356 and 423 participants were included in the efficacy and tolerability analyses, respectively. From the network meta-analysis, both bupropion and varenicline were more effective than placebo [odds ratio (OR) = 4.51, 95% credible interval (CrI) = 1.45-14.04 and OR = 5.17, 95% CrI = 1.78-15.06, respectively]. Data were insensitive to an assessment of varenicline versus bupropion (OR = 1.15, 95% CrI = 0.24-5.45). There were no significant differences in tolerability. All outcomes were rated by GRADE criteria as very low quality.
CONCLUSIONS
The limited evidence available to date suggests that bupropion and varenicline are effective and tolerable for smoking cessation in adults with serious mental illnesses.
Topics: Bupropion; Humans; Mental Disorders; Nicotinic Agonists; Smoking Cessation; Tobacco Use Cessation Devices; Tobacco Use Disorder; Treatment Outcome; Varenicline
PubMed: 26594837
DOI: 10.1111/add.13236