The (cost-) effectiveness of a combined strategy for smoking cessation: early prevention of the development of COPD in smokers who are at risk.
03 / 2002 - 03 / 2006
With the proposed study, the efficacy and cost-effectiveness of a combined strategy for smoking cessation in smokers who are at risk for developing COPD is assessed. Combination of non-nicotine pharmacotherapy (bupropion or nortriptyline) and individual support is compared to each other and to placebo treatment. Furthermore, determinants of success or failure of smoking cessation are identified and it is assessed to what extent they influence the treatment outcome. People who smoke find it difficult to stop. Of the forty percent of smokers in the United States who try to quit, only six percent succeeds in the long run. In Europe, these figures are even lower. The 'minimal intervention strategy' (MIS), an intervention programme for smoking cessation, has been successful in primary care.[2,3] Nevertheless, there is still much room for improvement, especially when it comes to perpetuation of the effect of intervention. According to the ASE-Model [4,5], success or failure of smoking cessation depends on a person's intention or motivation. The intention to quit smoking is determined by a person's attitude, social influence and (self-)efficacy with regard to smoking and smoking cessation. These three behavioural determinants are relevant during different motivational stages in the process of smoking cessation. With the use of nicotine replacement therapy [NRT] approximately 20% of the smokers who want to quit succeed in doing so. This means that 80% of the smokers who want to stop relapse to smoking again after some time. As a result, the interest in non-nicotine pharmacotherapy as an aid to smoking cessation has risen considerably since 1997. Especially the use of bupropion[1,6] and nortriptyline[7,8] seems promising. In recent years, several new treatment options have been identified. Especially the combination of some of the available modalities seems to be most effective and promising. Recently, the relative efficacy of combinations of NRT and non-nicotine replacement therapy [NNRT] with individual support have been addressed. Based on this study it can be concluded that at 12 months the combination of NNRT with individual support was more efficacious than NRT in combination with individual support (30.3% abstinent in the NNRT group compared to 16.4% abstinent in the NRT group). Furthermore, from meta-analyses on the efficacy of NRT and NNRT (i.e. bupropion or nortriptyline) it seems likely that compared to NRT, bupropion and nortriptyline are more efficacious (estimated odds ratio for bupropion [OR] 2.1 (95% confidence interval [CI] 1.5 - 3.0), OR nortriptyline 3.2 (95% CI 1.8 - 5.7)and for NRT OR 1.7 (95% CI 1.6 - 1.9)). In the proposed, study the comparison between bupropion and nortriptyline (in combination with individual counseling [MIS]) is being made because of the following reasons. Until now, bupropion is the only NNRT in the world (e.g. the Netherlands, USA) that is indicated as an aid to smoking cessation. However, looking at the results of a third meta-analysis, it could be argued that nortriptyline is more efficacious than bupropion (RR nortriptyline 2.7, 95% CI 1.3-5.3; RR bupropion 1.5, 95% CI 1.1-2.6; p=0.07). Furthermore, nortriptyline is much less expensive than bupropion, which means that important implications for cost-effective management of care can be expected. Chronic Obstructive Pulmonary Disease (COPD) is now the third most common cause of death in the Netherlands and is continuing to increase in both prevalence and mortality. Because the main cause of the disease is exposure to cigarette smoke (approximately 90% of the cases is caused by smoking cigarettes), deterioration of the lung function can be prevented if those smokers who are at risk for developing COPD can be detected before they actually develop COPD and help them to stop smoking. However, smokers face many difficulties in their efforts to stop smoking. According to the ASE-model, successful smoking cessation depends on the right combination of attitude, social influence and self-efficacy. Clinical research suggests that, the use of non-nicotine pharmacotherapy (i.e. bupropion and nortriptyline) in combination with counseling is the most effective strategy to help people stop smoking. In a randomised controlled clinical trial, we will compare the effects of bupropion to both placebo and nortriptyline, which is far less costly than bupropion. Two-hundred and twenty-five smokers who are at risk for developing COPD and who are motivated to stop smoking, will receive medication (or placebo) in combination with a structured intervention for smoking cessation (i.e. the Minimal Intervention Strategy [MIS]).