André Gervais

Pharmacotherapies for smoking cessation: a meta-analysis of randomized controlled trials

Background: Many placebo-controlled trials have demonstrated the efficacy of individual pharmacotherapies approved for smoking cessation. However, few direct or indirect comparisons of such interventions have been conducted. We performed a meta-analysis to compare the treatment effects of 7 approved pharmacologic interventions for smoking cessation. Methods: We searched the US Centers for Disease Control and Preventions Tobacco Information and Prevention database as well as MEDLINE, EMBASE and the Cochrane Library for published reports of placebo-controlled, double-blind randomized controlled trials of pharmacotherapies for smoking cessation. We included studies that reported biochemically validated measures of abstinence at 6 and 12 months. We used a hierarchical Bayesian random-effects model to summarize the results for each intervention. Results: We identified 70 published reports of 69 trials involving a total of 32 908 patients. Six of the 7 pharmacotherapies studied were found to be more efficacious than placebo: varenicline (odds ratio [OR] 2.41, 95% credible interval [CrI] 1.91–3.12), nicotine nasal spray (OR 2.37, 95% CrI 1.12–5.13), bupropion (OR 2.07, 95% CrI 1.73–2.55), transdermal nicotine (OR 2.07, 95% CrI 1.69–2.62), nicotine tablet (OR 2.06, 95% CrI 1.12–5.13) and nicotine gum (OR 1.71, 95% CrI 1.35–2.21). Similar results were obtained regardless of which measure of abstinence was used. Although the point estimate favoured nicotine inhaler over placebo (OR 2.17), these results were not conclusive because the credible interval included unity (95% CrI 0.95–5.43). When all 7 interventions were included in the same model, all were more efficacious than placebo. In our analysis of data from the varenicline trials that included bupropion control arms, we found that varenicline was superior to bupropion (OR 2.18, 95% CrI 1.09–4.08). Interpretation: Varenicline, bupropion and the 5 nicotine replacement therapies were all more efficacious than placebo at promoting smoking abstinence at 6 and 12 months.

Behavioural interventions for smoking cessation : a meta-analysis of randomized controlled trials

AIMS Widely varying estimates of treatment effects have been reported in randomized controlled trials (RCTs) investigating the efficacy of behavioural interventions for smoking cessation. Previous meta-analyses investigating behavioural interventions have important limitations and do not include recently published RCTs. We undertook a meta-analysis of RCTs to synthesize the treatment effects of four behavioural interventions, including minimal clinical intervention (brief advice from a healthcare worker), and intensive interventions, including individual, group, and telephone counselling. METHODS AND RESULTS We searched the CDC Tobacco Information and Prevention, Cochrane Library, EMBASE, Medline, and PsycINFO databases. We included only RCTs that reported biochemically validated smoking cessation outcomes at 6 and/or 12 months after the target quit date. Outcomes were aggregated using hierarchical Bayesian random-effects models. We identified 50 RCTs, which randomized n = 26 927 patients (minimal clinical intervention: 9 RCTs, n = 6456; individual counselling: 23 RCTs, n = 8646; group counselling: 12 RCTs, n = 3600; telephone counselling: 10 RCTs, n = 8225). The estimated mean treatment effects were minimal clinical intervention [odds ratio (OR) 1.50, 95% credible interval (CrI) 0.84-2.78], individual counselling (OR 1.49, 95% CrI 1.08-2.07), group counselling (OR 1.76, 95% CrI 1.11-2.93), and telephone counselling (OR 1.58, 95% CrI 1.15-2.29). CONCLUSION Intensive behavioural interventions result in substantial increases in smoking abstinence compared with control. Although minimal clinical intervention may increase smoking abstinence, there is insufficient evidence to draw strong conclusions regarding its efficacy.

Bupropion for Smoking Cessation in Patients Hospitalized With Acute Myocardial Infarction: A Randomized, Placebo-Controlled Trial

OBJECTIVES The purpose of this study was to examine smoking cessation rates among smokers with AMI to determine whether bupropion, started in-hospital, is safe and can improve cessation rates at 1 year. BACKGROUND Bupropion doubles quit rates in otherwise healthy smokers and patients with stable cardiovascular disease. Although 2 previous trials examined the use of bupropion in patients hospitalized with acute cardiovascular disease, these studies have been inconclusive with respect to its safety and efficacy in patients with acute myocardial infarction (AMI). METHODS We conducted a multicenter, double-blind, placebo-controlled, randomized trial in smokers hospitalized with AMI. Participants received bupropion or placebo for 9 weeks and were followed for 12 months. Both groups received low-intensity counseling. Point prevalence abstinence was assessed by 7-day recall and biochemical validation of expired carbon monoxide. RESULTS A total of 392 patients were randomized (mean age 53.9 ± 10.3 years); 83.5% were male; 64.9% had ST-segment elevation myocardial infarction). Patients smoked a mean of 23.2 ± 10.6 cigarettes/day for a mean of 32.9 ± 12.4 years. At 12 months, point prevalence abstinence rates were 37.2% in the bupropion group and 32.0% in the placebo group (p = 0.33; % difference after adjusting for between center differences 3.9%). Continuous abstinence rates were 26.8% and 22.2%, respectively (p = 0.34). Major adverse cardiac event rates were similar (13.0% vs. 11.0%, respectively; p = 0.64). CONCLUSIONS Two-thirds of patients return to smoking by 12 months after AMI. Bupropion is well tolerated and seems to be safe to use in the immediate post-AMI period. However, bupropion is not effective for smoking cessation in patients post-AMI.

Smoking cessation attempts among adolescent smokers: a systematic review of prevalence studies

Objective: To synthesise estimates of the prevalence of cessation attempts among adolescent smokers generally, and according to age and level of cigarette consumption. Data sources: PubMed, ERIC, and PsychInfo databases and Internet searches of central data collection agencies. Study selection: National population-based studies published in English between 1990 and 2005 reporting the prevalence, frequency and/or duration of cessation attempts among smokers aged ⩾10 to <20 years. Data extraction: Five reviewers determined inclusion criteria for full-text reports. One reviewer extracted data on the design, population characteristics and results from the reports. Data synthesis: In total, 52 studies conformed to the inclusion criteria. The marked heterogeneity that characterised the study populations and survey questions precluded a meta-analysis. Among adolescent current smokers, the median 6-month, 12-month and lifetime cessation attempt prevalence was 58% (range: 22–73%), 68% (range 43–92%) and 71% (range 28–84%), respectively. More than half had made multiple attempts. Among smokers who had attempted cessation, the median prevalence of relapse was 34, 56, 89 and 92% within 1 week, 1 month, 6 months, and 1 year, respectively, following the longest attempt. Younger (age<16 years) and non-daily smokers experienced a similar or higher prevalence of cessation attempts compared with older (age ⩾16 years) or daily smokers. Moreover, the prevalence of relapse by 6 months following the longest cessation attempt was similar across age and smoking frequency. Conclusions: The high prevalence of cessation attempts and relapse among adolescent smokers extends to young adolescents and non-daily smokers. Cessation surveillance, research and program development should be more inclusive of these subgroups.

Nicotine dependence symptoms among young never-smokers exposed to secondhand tobacco smoke

BACKGROUND To extend previous observations that secondhand tobacco smoke (SHS) is associated with nicotine markers in children, we investigated if SHS exposure is associated with self-reports of nicotine dependence (ND) symptoms among young never-smokers. METHOD Data on number of persons who smoke inside the home, number of days exposed to SHS in a motor vehicle in the past week, number of parents, siblings, and friends who smoke, and ND symptoms, were collected from 10-12 year-old students in self-report questionnaires. The association between SHS and ND symptoms among young never-smokers was assessed in logistic regression models. RESULTS Sixty-nine of 1488 never-smokers (5%) reported one or more ND symptom. After controlling for sibling and peer smoking, and susceptibility to initiating smoking, exposure to SHS in a motor vehicle was independently associated with ND symptoms (OR, 95% CI=1.2, 1.0-1.4). The OR for number of persons who smoke inside the home was 1.1 (0.9-1.4). CONCLUSION SHS exposure in motor vehicles may be associated with ND symptoms among young never-smokers. If replicated, this finding provides support for interventions that promote non-smoking in motor vehicles.

Clinical ResearchClinical TrialBupropion for Smoking Cessation in Patients Hospitalized With Acute Myocardial Infarction: A Randomized, Placebo-Controlled Trial

OBJECTIVES The purpose of this study was to examine smoking cessation rates among smokers with AMI to determine whether bupropion, started in-hospital, is safe and can improve cessation rates at 1 year. BACKGROUND Bupropion doubles quit rates in otherwise healthy smokers and patients with stable cardiovascular disease. Although 2 previous trials examined the use of bupropion in patients hospitalized with acute cardiovascular disease, these studies have been inconclusive with respect to its safety and efficacy in patients with acute myocardial infarction (AMI). METHODS We conducted a multicenter, double-blind, placebo-controlled, randomized trial in smokers hospitalized with AMI. Participants received bupropion or placebo for 9 weeks and were followed for 12 months. Both groups received low-intensity counseling. Point prevalence abstinence was assessed by 7-day recall and biochemical validation of expired carbon monoxide. RESULTS A total of 392 patients were randomized (mean age 53.9 ± 10.3 years); 83.5% were male; 64.9% had ST-segment elevation myocardial infarction). Patients smoked a mean of 23.2 ± 10.6 cigarettes/day for a mean of 32.9 ± 12.4 years. At 12 months, point prevalence abstinence rates were 37.2% in the bupropion group and 32.0% in the placebo group (p = 0.33; % difference after adjusting for between center differences 3.9%). Continuous abstinence rates were 26.8% and 22.2%, respectively (p = 0.34). Major adverse cardiac event rates were similar (13.0% vs. 11.0%, respectively; p = 0.64). CONCLUSIONS Two-thirds of patients return to smoking by 12 months after AMI. Bupropion is well tolerated and seems to be safe to use in the immediate post-AMI period. However, bupropion is not effective for smoking cessation in patients post-AMI.

A systematic review of the Diagnostic and Statistical Manual diagnostic criteria for nicotine dependence

The Diagnostic and Statistical Manual diagnostic criteria for nicotine dependence (DSM-ND) are based on the proposition that dependence is a syndrome that can be diagnosed only when a minimum of 3 of the 7 proscribed features are present. The DSM-ND criteria are an accepted research measure, but the validity of these criteria has not been subjected to a systematic evaluation. To systematically review evidence of validity and reliability for the DSM-ND criteria, a literature search was conducted of 16 national and international databases. Each article with original data was independently reviewed by two or more reviewers. In total, 380 potentially relevant articles were examined and 169 were reviewed in depth. The DSM-ND criteria have seen wide use in research settings, but sensitivity and specificity are well below the accepted standards for clinical applications. Predictive validity is generally poor. The 7 DSM-ND criteria are regarded as having face validity, but no data support a 3-symptom ND diagnostic threshold, or a 4-symptom withdrawal syndrome threshold. The DSM incorrectly states that daily smoking is a prerequisite for withdrawal symptoms. The DSM shows poor to modest concurrence with all other measures of nicotine dependence, smoking behaviors and biological measures of tobacco use. The data support the DSM-ND criteria as a valid measure of nicotine dependence severity for research applications. However, the data do not support the central premise of a 3-symptom diagnostic threshold, and no data establish that the DSM-ND criteria provide an accurate diagnosis of nicotine dependence.

Milestones in the Process of Cessation Among Novice Adolescent Smokers

OBJECTIVES We sought to document the sequence and timing of milestones in the process of smoking cessation by prospectively studied cessation milestones among novice adolescent smokers. METHODS Participants, aged 12 to 13 years in 1999 (n = 1293), completed self-report questionnaires every 3 months during the school year over 5 years. We ascertained time after first puff to attain 5 cessation milestones among 319 participants who initiated cigarette smoking during follow-up. RESULTS The cumulative probability of first reports of a serious desire to quit and perceived permanent cessation was 25% at 1.5 months (95% confidence interval [CI] = 1.5, 2.5) after the first puff. The first serious quit attempt occurred at 2.5 months (95% CI = 2.5, 5.4), lack of confidence about quitting followed at 18.4 months (95% CI = 18.4, 26.8), and awareness of the difficulty of quitting occurred at 32.2 months (95% CI = 19.2, 38.4). CONCLUSIONS Desire and attempts to quit began soon after smoking onset. Novice smokers progressed through several stages in their perception of the difficulty of quitting. Increased understanding of the cessation process may help in developing effective tobacco control interventions for novice smokers.

The effect of smoking cessation counselling in pregnant women: a meta‐analysis of randomised controlled trials

Please cite this paper as: Filion K, Abenhaim H, Mottillo S, Joseph L, Gervais A, O’Loughlin J, Paradis G, Pihl R, Pilote L, Rinfret S, Tremblay M, Eisenberg M. The effect of smoking cessation counselling in pregnant women: a meta‐analysis of randomised controlled trials. BJOG 2011;118:1422–1428.

Cohort Profile: The Nicotine Dependence in Teens (NDIT) Study

The Nicotine Dependence in Teens (NDIT) study is a prospective cohort investigation of 1294 students recruited in 1999-2000 from all grade 7 classes in a convenience sample of 10 high schools in Montreal, Canada. Its primary objectives were to study the natural course and determinants of cigarette smoking and nicotine dependence in novice smokers. The main source of data was self-report questionnaires administered in class at school every 3 months from grade 7 to grade 11 (1999-2005), for a total of 20 survey cycles during high school education. Questionnaires were also completed after graduation from high school in 2007-08 and 2011-12 (survey cycles 21 and 22, respectively) when participants were aged 20 and 24 years on average, respectively. In addition to its primary objectives, NDIT has embedded studies on obesity, blood pressure, physical activity, team sports, sedentary behaviour, diet, genetics, alcohol use, use of illicit drugs, second-hand smoke, gambling, sleep and mental health. Results to date are described in 58 publications, 20 manuscripts in preparation, 13 MSc and PhD theses and 111 conference presentations. Access to NDIT data is open to university-appointed or affiliated investigators and to masters, doctoral and postdoctoral students, through their primary supervisor (www.nditstudy.ca).