Paul Aveyard

Influence of smoking cessation after diagnosis of early stage lung cancer on prognosis: systematic review of observational studies with meta-analysis

Objective To systematically review the evidence that smoking cessation after diagnosis of a primary lung tumour affects prognosis. Design Systematic review with meta-analysis. Data sources CINAHL (from 1981), Embase (from 1980), Medline (from 1966), Web of Science (from 1966), CENTRAL (from 1977) to December 2008, and reference lists of included studies. Study selection Randomised controlled trials or observational longitudinal studies that measured the effect of quitting smoking after diagnosis of lung cancer on prognostic outcomes, regardless of stage at presentation or tumour histology, were included. Data extraction Two researchers independently identified studies for inclusion and extracted data. Estimates were combined by using a random effects model, and the I2 statistic was used to examine heterogeneity. Life tables were used to model five year survival for early stage non-small cell lung cancer and limited stage small cell lung cancer, using death rates for continuing smokers and quitters obtained from this review. Results In 9/10 included studies, most patients studied were diagnosed as having an early stage lung tumour. Continued smoking was associated with a significantly increased risk of all cause mortality (hazard ratio 2.94, 95% confidence interval 1.15 to 7.54) and recurrence (1.86, 1.01 to 3.41) in early stage non-small cell lung cancer and of all cause mortality (1.86, 1.33 to 2.59), development of a second primary tumour (4.31, 1.09 to 16.98), and recurrence (1.26, 1.06 to 1.50) in limited stage small cell lung cancer. No study contained data on the effect of quitting smoking on cancer specific mortality or on development of a second primary tumour in non-small cell lung cancer. Life table modelling on the basis of these data estimated 33% five year survival in 65 year old patients with early stage non-small cell lung cancer who continued to smoke compared with 70% in those who quit smoking. In limited stage small cell lung cancer, an estimated 29% of continuing smokers would survive for five years compared with 63% of quitters on the basis of the data from this review. Conclusions This review provides preliminary evidence that smoking cessation after diagnosis of early stage lung cancer improves prognostic outcomes. From life table modelling, the estimated number of deaths prevented is larger than would be expected from reduction of cardiorespiratory deaths after smoking cessation, so most of the mortality gain is likely to be due to reduced cancer progression. These findings indicate that offering smoking cessation treatment to patients presenting with early stage lung cancer may be beneficial.

Effectiveness and safety of nicotine replacement therapy assisted reduction to stop smoking: systematic review and meta-analysis

Objective To determine the effectiveness and safety of nicotine replacement therapy assisted reduction to stop smoking. Design Systematic review of randomised controlled trials. Data sources Cochrane Library, Medline, Embase, CINAHL, PsychINFO, Science Citation Index, registries of ongoing trials, reference lists, the drug company that sponsored most of the trials, and clinical experts. Review methods Eligible studies were published or unpublished randomised controlled trials that enrolled smokers who declared no intention to quit smoking in the short term, and compared nicotine replacement therapy (with or without motivational support) with placebo, no treatment, other pharmacological therapy, or motivational support, and reported quit rates. Two reviewers independently applied eligibility criteria. One reviewer assessed study quality and extracted data and these processes were checked by a second reviewer. The primary outcome, six months sustained abstinence from smoking beginning during treatment, was assessed by individual patient data analysis. Other outcomes were cessation and reduction at end of follow-up, and adverse events. Data synthesis Seven placebo controlled randomised controlled trials were included (four used nicotine replacement therapy gum, two nicotine replacement therapy inhaler, and one free choice of therapy). They were reduction studies that reported smoking cessation as a secondary outcome. The trials enrolled a total of 2767 smokers, gave nicotine replacement therapy for 6-18 months, and lasted 12-26 months. 6.75% of smokers receiving nicotine replacement therapy attained sustained abstinence for six months, twice the rate of those receiving placebo (relative risk (fixed effects) 2.06, 95% confidence interval 1.34 to 3.15; (random effects) 1.99, 1.01 to 3.91; five trials). The number needed to treat was 29. All other cessation and reduction outcomes were significantly more likely in smokers given nicotine replacement therapy than those given placebo. There were no statistically significant differences in adverse events (death, odds ratio 1.00, 95% confidence interval 0.25 to 4.02; serious adverse events, 1.16, 0.79 to 1.50; and discontinuation because of adverse events, 1.25, 0.64 to 2.51) except nausea, which was more common with nicotine replacement therapy (8.7% v 5.3%; odds ratio 1.69, 95% confidence interval 1.21 to 2.36). Conclusions Available trials indicate that nicotine replacement therapy is an effective intervention in achieving sustained smoking abstinence for smokers who have no intention or are unable to attempt an abrupt quit. Most of the evidence, however, comes from trials with regular behavioural support and monitoring and it is unclear whether using nicotine replacement therapy without regular contact would be as effective.

Comparison of range of commercial or primary care led weight reduction programmes with minimal intervention control for weight loss in obesity: Lighten Up randomised controlled trial

Objective To assess the effectiveness of a range of weight management programmes in terms of weight loss. Design Eight arm randomised controlled trial. Setting Primary care trust in Birmingham, England. Participants 740 obese or overweight men and women with a comorbid disorder identified from general practice records. Interventions Weight loss programmes of 12 weeks’ duration: Weight Watchers; Slimming World; Rosemary Conley; group based, dietetics led programme; general practice one to one counselling; pharmacy led one to one counselling; choice of any of the six programmes. The comparator group was provided with 12 vouchers enabling free entrance to a local leisure (fitness) centre. Main outcome measures The primary outcome was weight loss at programme end (12 weeks). Secondary outcomes were weight loss at one year, self reported physical activity, and percentage weight loss at programme end and one year. Results Follow-up data were available for 658 (88.9%) participants at programme end and 522 (70.5%) at one year. All programmes achieved significant weight loss from baseline to programme end (range 1.37 kg (general practice) to 4.43 kg (Weight Watchers)), and all except general practice and pharmacy provision resulted in significant weight loss at one year. At one year, only the Weight Watchers group had significantly greater weight loss than did the comparator group (2.5 (95% confidence interval 0.8 to 4.2) kg greater loss,). The commercial programmes achieved significantly greater weight loss than did the primary care programmes at programme end (mean difference 2.3 (1.3 to 3.4) kg). The primary care programmes were the most costly to provide. Participants allocated to the choice arm did not have better outcomes than those randomly allocated to a programme. Conclusions Commercially provided weight management services are more effective and cheaper than primary care based services led by specially trained staff, which are ineffective. Trial registration Current Controlled Trials ISRCTN25072883.

Change in mental health after smoking cessation: systematic review and meta-analysis

Objective To investigate change in mental health after smoking cessation compared with continuing to smoke. Design Systematic review and meta-analysis of observational studies. Data sources Web of Science, Cochrane Central Register of Controlled Trials, Medline, Embase, and PsycINFO for relevant studies from inception to April 2012. Reference lists of included studies were hand searched, and authors were contacted when insufficient data were reported. Eligibility criteria for selecting studies Longitudinal studies of adults that assessed mental health before smoking cessation and at least six weeks after cessation or baseline in healthy and clinical populations. Results 26 studies that assessed mental health with questionnaires designed to measure anxiety, depression, mixed anxiety and depression, psychological quality of life, positive affect, and stress were included. Follow-up mental health scores were measured between seven weeks and nine years after baseline. Anxiety, depression, mixed anxiety and depression, and stress significantly decreased between baseline and follow-up in quitters compared with continuing smokers: the standardised mean differences (95% confidence intervals) were anxiety −0.37 (95% confidence interval −0.70 to −0.03); depression −0.25 (−0.37 to −0.12); mixed anxiety and depression −0.31 (−0.47 to −0.14); stress −0.27 (−0.40 to −0.13). Both psychological quality of life and positive affect significantly increased between baseline and follow-up in quitters compared with continuing smokers 0.22 (0.09 to 0.36) and 0.40 (0.09 to 0.71), respectively). There was no evidence that the effect size differed between the general population and populations with physical or psychiatric disorders. Conclusions Smoking cessation is associated with reduced depression, anxiety, and stress and improved positive mood and quality of life compared with continuing to smoke. The effect size seems as large for those with psychiatric disorders as those without. The effect sizes are equal or larger than those of antidepressant treatment for mood and anxiety disorders.

Weight gain in smokers after quitting cigarettes: meta-analysis

Objective To describe weight gain and its variation in smokers who achieve prolonged abstinence for up to 12 months and who quit without treatment or use drugs to assist cessation. Design Meta-analysis. Data sources We searched the Central Register of Controlled Trials (CENTRAL) and trials listed in Cochrane reviews of smoking cessation interventions (nicotine replacement therapy, nicotinic partial agonists, antidepressants, and exercise) for randomised trials of first line treatments (nicotine replacement therapy, bupropion, and varenicline) and exercise that reported weight change. We also searched CENTRAL for trials of interventions for weight gain after cessation. Review methods Trials were included if they recorded weight change from baseline to follow-up in abstinent smokers. We used a random effects inverse variance model to calculate the mean and 95% confidence intervals and the mean of the standard deviation for weight change from baseline to one, two, three, six, and 12 months after quitting. We explored subgroup differences using random effects meta-regression. Results 62 studies were included. In untreated quitters, mean weight gain was 1.12 kg (95% confidence interval 0.76 to 1.47), 2.26 kg (1.98 to 2.54), 2.85 kg (2.42 to 3.28), 4.23 kg (3.69 to 4.77), and 4.67 kg (3.96 to 5.38) at one, two, three, six, and 12 months after quitting, respectively. Using the means and weighted standard deviations, we calculated that at 12 months after cessation, 16%, 37%, 34%, and 13% of untreated quitters lost weight, and gained less than 5 kg, gained 5-10 kg, and gained more than 10 kg, respectively. Estimates of weight gain were similar for people using different pharmacotherapies to support cessation. Estimates were also similar between people especially concerned about weight gain and those not concerned. Conclusion Smoking cessation is associated with a mean increase of 4-5 kg in body weight after 12 months of abstinence, and most weight gain occurs within three months of quitting. Variation in weight change is large, with about 16% of quitters losing weight and 13% gaining more than 10 kg.

Brief opportunistic smoking cessation interventions: A systematic review and meta-analysis to compare advice to quit and offer of assistance

AIMS This study aimed to assess the effects of opportunistic brief physician advice to stop smoking and offer of assistance on incidence of attempts to stop and quit success in smokers not selected by motivation to quit. METHODS We included relevant trials from the Cochrane Reviews of physician advice for smoking cessation, nicotine replacement therapy (NRT), varenicline and bupropion. We extracted data on quit attempts and quit success. Estimates were combined using the Mantel-Haentszel method and heterogeneity assessed with the I(2) statistic. Study quality was assessed by method of randomization, allocation concealment and follow-up blind to allocation. RESULTS Thirteen studies were included. Compared to no intervention, advice to quit on medical grounds increased the frequency of quit attempts [risk ratio (RR) 1.24, 95% confidence interval (CI): 1.16-1.33], but not as much as behavioural support for cessation (RR 2.17, 95% CI 1.52-3.11) or offering NRT (RR 1.68, 95% CI: 1.48-1.89). In a direct comparison, offering assistance generated more quit attempts than giving advice to quit on medical grounds (RR 1.69, 95% CI: 1.24-2.31 for behavioural support and 1.39, 95% CI: 1.25-1.54 for offering medication). There was evidence that medical advice increased the success of quit attempts and inconclusive evidence that offering assistance increased their success. CONCLUSIONS Physicians may be more effective in promoting attempts to stop smoking by offering assistance to all smokers than by advising smokers to quit and offering assistance only to those who express an interest in doing so.

Waterpipe smoking in students: Prevalence, risk factors, symptoms of addiction, and smoke intake. Evidence from one British university

BackgroundAnecdotal reports suggest waterpipe smoking is becoming common in students in western countries. The aim was to examine prevalence, risk factors, symptoms of addiction, and smoke intake.MethodsThis was a cross-sectional survey of students with subsidiary survey of regular waterpipe user and survey of exhaled carbon monoxide (CO) before and after waterpipe smoking in customers of a waterpipe café. 937 students of Birmingham University completed the initial survey with a follow up of 21 regular waterpipe smokers. 63 customers of a waterpipe café near the University completed the study of CO intake.Results355 (37.9%, 95% confidence intervals (CI) 34.8 to 41.1%) students had tried waterpipes, the prevalence of trying rising with duration at University. 75 (8.0%, 95%CI 6.4 to 10.0%) were regular smokers, similar to the prevalence of cigarette smoking (9.4%). Although cigarette smoking was the major risk factor for being a regular waterpipe smoker, odds ratio (95%CI) 2.77 (1.52 to 5.06), 65% of waterpipe smokers did not smoke cigarettes. Seven of 21 (33.3%) regular waterpipe smokers experienced cravings. Nearly all regular waterpipe users thought it less harmful than smoking cigarettes. The mean (standard deviation) rise in CO was 37.4 (25.8)ppm, nearly twice as high as a typical cigarette smoker seeking cessation treatment.ConclusionWaterpipe smoking is a common part of student culture in one British university, as in the Middle East and in the United States. It poses a potential threat to public health, with evidence of dependence and high smoke intake.

Cluster randomised controlled trial of expert system based on the transtheoretical (“stages of change”) model for smoking prevention and cessation in schools

Abstract Objectives: To examine whether a year long programme based on the transtheoretical model of behaviour change, incorporating three sessions using an expert system computer program and three class lessons, could reduce the prevalence of teenage smoking. Design: Cluster randomised trial comparing the intervention to a control group exposed only to health education as part of the English national curriculum. Setting: 52 schools in the West Midlands region. Participants: 8352 students in year 9 (age 13-14 years) at those schools. Main outcome measures: Prevalence of teenage smoking 12 months after the start of the intervention. Results: Of the 8352 students recruited, 7444 (89.1%) were followed up at 12 months. The intention to treat odds ratio for smoking in the intervention group relative to control was 1.08 (95% confidence interval 0.89 to 1.33). Sensitivity analysis for loss to follow up and adjustment for potential confounders did not alter these findings. Conclusions: The smoking prevention and cessation intervention based on the transtheoretical model, as delivered in this trial, is ineffective in schoolchildren aged 13-14. Key messages The transtheoretical model proposes that individuals move through a series of stages in behaviour change A computer programme gave 13 and 14 year old school students tailored information about what stage they were in and what to do to move to the next stage Students given this information were no more likely to move stage, refrain from smoking, or stop smoking than those exposed to ordinary classroom health education There is no evidence that the computerised expert system based on the transtheoretical model is effective in smoking prevention and cessation

Managing smoking cessation

Cross sectional studies show that most smokers in countries such as the United Kingdom and the United States report that they want to stop and intend to stop at some point.1 The rate of attempts to stop is high—78 attempts per 100 smokers per year in the UK—with many smokers making several attempts in a year.2 Nearly half of all smokers expect not to be smoking in a years time,3 but only 2-3% actually stop permanently each year.3 The most common reasons smokers give for smoking are stress relief and enjoyment,4 but the main reason is nicotine dependence. Nicotine acts in the midbrain, creating impulses to smoke in the face of stimuli associated with smoking.5 Consequent changes in brain chemistry also produce “nicotine hunger” when a smoker goes without nicotine. A third mechanism underlying nicotine dependence is nicotine withdrawal: unpleasant mood and physical symptoms that occur on abstinence and are relieved by smoking.6 7 Nicotine dependence is the main reason that most unassisted quit attempts fail within a week.8 We give evidence based recommendations and new treatment options for healthcare professionals to increase the success rate of these attempts. Most evidence for treatment comes from randomised controlled trials summarised in the Cochrane reviews for tobacco dependence. #### Summary points

Cost-Effectiveness of Pharmacological Interventions for Smoking Cessation: A Literature Review and a Decision Analytic Analysis

To evaluate the relative cost-effectiveness of nicotine replacement therapy (NRT) and bupropion SR for smoking cessation, the authors reviewed published studies and developed a decision analytic model from the UK National Health Services perspective. Irrespective of the methods or assumptions involved, the results of published studies consistently indicated that NRT for smoking cessation is cost-effective. No published studies have evaluated the relative cost-effectiveness of bupropion SR for smoking cessation. The results of the decision analyses indicated that, as compared with advice or counseling alone, the incremental cost per life-years saved is about