Objective: Increasing smoking cessation rates is an important goal in preventing lung cancer and COPD. Nicotine replacement therapy (NRT) has been found in clinical trials to improve the chances of success at stopping but recent cross-sectional survey data have raised doubts as to whether it is effective when used by smokers making quit attempts unsupervised outside of clinical trials. Because of biases inherent in retrospective surveys, this issue can only be adequately addressed using longitudinal studies and this paper reports the first study of its kind to examine the issue.
Design: The ATTEMPT cohort is a multinational cohort study with data collection by internet which recruited smokers of five or more cigarettes per day, aged 35-65 years, intending to stop smoking within the next three months. Phase 1 of ATTEMPT began in Spring 2003 and involved 2009 smokers from the US, UK, Canada, and France. Phase 2 involved 3645 smokers and included the same countries plus Spain. Follow-ups were carried out every three months. Participants From Phase 1 we identified 492 smokers who made a quit attempt without formal behavioural support or bupropion in the first three-month follow-up period, of whom 357 were followed up for a further six months. The Phase 2 sample involved 906 smokers making quit attempts of whom 732 were followed up. Main outcome measures At baseline, demographic characteristics, smoking history and nicotine dependence were assessed. Smokers who made quit attempts were questioned on methods used to aid them. The main outcome measure was self-report of complete abstinence throughout both of the 3-month periods following the quit date.
Results: A total of 35.6% of Phase 1 smokers used NRT; the figure for Phase 2 was 29.6%. The odds ratios comparing six months' abstinence in those using versus not using NRT, adjusting for nicotine dependence, were 3.0 (1.2-7.5) for Phase 1 sample and 2.1 (1.0-4.1) for Phase 2 sample. The difference in success rates of those using NRT versus those not using it, adjusted for FTND score, was 6% in the Phase 1 sample and 3.7% in the Phase 2 sample. The improved odds of success were not explicable in terms of motivation to use some form of aid to cessation or differential loss to follow-up.
Conclusion: NRT use by smokers making self-initiated quit attempts without formal behavioural support is associated with improved long-term abstinence rates.
- smoking cessation