P1.1 Smoking cessation

Smoking cessation is the most important intervention to prevent the worsening of COPD [evidence level II, strong recommendation]

Australia has made substantial progress in reducing the prevalence of tobacco smoking. In 2017-18 the prevalence of daily smoking in adults (people aged 18 and over) was 13.8% compared to 16.1% in 2011-12 and 23.8% in 1995.  The proportion of First Nations people aged 15 years and over was 37% in 2018-19, a decrease from 41% in 2012-13. Despite the decrease in prevalence in 2018 tobacco use remained the leading risk factor contributing to disease burden and death (8.6% of total disease burden). In 2018 tobacco use was estimated to be the cause of death for almost 20,500 Australians.

The Australian National Tobacco Strategy 2023-2030 (Commonwealth of Australia 2023) aims to achieve a national daily smoking prevalence of less than 10% by 2025 and 5% or less by 2030. For First Nations people the goal is to reduce daily smoking to 27% or less by 2030. One of the priorities of the strategy is to provide greater access to evidence-based cessation services to help people quit tobacco. Actions related to this priority include improving and extending Quitline services, providing policy guidelines and accredited training in smoking cessation and reviewing restrictions on and the access to smoking cessation pharmacotherapies on the PBS.

Comprehensive treatment of tobacco dependence involves providing both behavioural support and pharmacotherapy (Zwar 2014). International data show that smoking cessation strategies are cost effective but with a 10-fold range in cost per life-year gained depending on the intensity of the program and the use of pharmacological therapies (Ekpu 2015). A range of health professionals can help smokers quit (Rice 2013Stead 2013aCarr 2012Sinclair 2004) but relapse is common [evidence level I].

Currently accepted best practice is summarised in the 5-A strategy (Zwar 2014):

  • Ask and identify smokers. Document smoking status in the medical record.
  • Assess the degree of nicotine dependence and motivation or readiness to quit
  • Advise smokers about the risks of smoking and benefits of quitting and discuss options
  • Assist cessation — this may include specific advice about pharmacological interventions or referral to a formal cessa­tion program such as the Quitline
  • Arrange follow-up to reinforce messages

Brief interventions for smoking cessation involve opportunistic advice, encouragement and referral. Quit Victoria has summarised this as Ask, Advise, Help.

The brief advice model has three steps:

  • Ask all patients about smoking status and document this in their medical record.
  • Advise all patients who smoke to quit in a clear, non-confrontational and personalised way, focusing on the benefits of quitting and advising of the best way to quit.
  • Help by offering referral to behavioural intervention through Quitline (13 7848) and prescribe (or help patients to access) pharmacotherapy, such as nicotine replacement therapy.

Cessation rates increase with the amount of support and intervention, including practical counselling and social support arranged outside of treatment.

People with COPD often have barriers to smoking cessation. There is evidence that smokers with COPD report lower self-efficacy and lower self-esteem, impairing their ability to quit. Co-existing depression is common with depression reported in 44% of hospitalised patients with COPD (Jimenez-Ruiz 2015). Despite this there is evidence that smoking cessation interventions can be effective. The 2016 update of the Cochrane Review (van Eerd 2016) on smoking cessation for people with COPD includes 16 studies involving 13,123 participants. Only two studies were rated as high quality. The review found high-quality evidence from a meta-analysis of four (1,540 participants) of the 16 studies that a combination of behavioural treatment and pharmacotherapy is effective in helping smokers with COPD to quit smoking.

A systematic review of behaviour change techniques to support smoking cessation in patients with COPD found that four techniques were associated with higher rates of cessation. The behaviour change techniques found to be effective (usually in comparison to usual care) were; facilitate action planning/develop treatment plan, prompt self-recording, advise on methods of weight control, and advise on/facilitate use of social support. In addition, linking COPD and smoking was found to result in significantly larger effect sizes (Bartlett 2014) [evidence level I]. Personalising smoking cessation advice based on lung function results increase cessation rates (Parkes 2008) [evidence level II].

Smoking tobacco can alter the metabolism of a number of medicines. This is primarily due to substances in tobacco smoke, such as hydrocarbons or tar-like products that cause induction of some liver enzymes (CYP 1A2, in particular). When a person stops smoking, the enzyme activity returns to normal, which may result in increased levels of these medicines in the blood. Monitoring and dosage reduction may often be required. For information on medicines affected by smoking see Appendix 3 of the RACGP smoking cessation guidelines (http://www.racgp.org.au/your-practice/guidelines/smoking-cessation/). Heavy marijuana smoking (> 20 joint-years of exposure) increases the risk of COPD and accelerates FEV₁ decline in concomitant tobacco smokers beyond that observed with tobacco alone (Tan 2019).