Association between duration of use of pharmacotherapy and smoking cessation: findings from a national survey.

Objective: To investigate the association of the duration of use of prescription medications and nicotine replacement therapy (NRT) with smoking cessation using a national sample of the general population in the USA, controlling for nicotine dependence and sociodemographic variables.

Setting Usa Participants: We used data from the 2010-2011 Tobacco Use Supplement to the US Current Population Survey. We limited the analysis to current daily smokers who made a quit attempt in the past year and former smokers who were a daily smoker 1 year prior to the survey (n=8263). Respondents were asked about duration of use of prescription medication (varenicline, bupropion, other) and NRT (nicotine patch, gum/lozenges, nasal spray and inhaler) for smoking cessation.

Primary Outcome Measure: Successful smoking cessation. Individuals who reported to have smoked at least 100 cigarettes in their lifetime but were not smoking at all at the time of the interview and were a daily smoker 1 year prior to the interview were considered to have successfully quit smoking.

Results: After adjusting for daily cigarette consumption and sociodemographic covariates, we found evidence for an association between duration of pharmacotherapy use and smoking cessation (p<0.001). Adjusted cessation rates for those who used prescription medication or NRT for 5+ weeks were 28.8% and 27.8%, respectively. Adjusted cessation rates for those who used prescription medication or NRT for less than 5 weeks varied from 6.2% to 14.5%. Adjusted cessation rates for those who used only behavioural counselling and those who attempted to quit smoking unassisted were 16.1% and 16.4%, respectively.

Conclusions: Use of pharmacotherapy for at least 5 weeks is associated with increased likelihood of successful smoking cessation. Results suggest that encouraging smokers who intend to quit to use pharmacotherapy and to adhere to treatment duration can help improve chances of successful cessation.