Introduction. Integrating smoking cessation support into lung cancer screening can improve abstinence rates. However, healthcare decision makers need evidence of cost effectiveness to understand the cost/benefit of adopting this approach. Methods. To evaluate the cost-effectiveness of different smoking cessation interventions, and service delivery, we used a Markov model, adapted from previous National Institute for Health and Care Excellence guidelines on smoking cessation. This uses long-term epidemiological data to capture the prevalence of the smoking-related illnesses, where prevalence is estimated based on age, sex, and smoking status. Probabilistic sensitivity analysis was conducted to capture joint parameter uncertainty. Results. All smoking cessation interventions appeared cost-effective at a threshold of 20,000 pounds per quality-adjusted life year, compared to no intervention or behavioural support alone. Offering immediate smoking cessation as part of lung cancer screening appointments, compared with usual care (onward referral to stop smoking services) was also estimated to be cost-effective with a net monetary benefit of 2,198 pounds per person, and a saving of between 34 and 79 pounds per person in reduced workplace absenteeism among working age attendees. Estimated healthcare cost savings were more than four times greater in the most deprived quintile compared to the least deprived, alongside a fivefold increase in QALYs accrued. Conclusions. Smoking cessation interventions within lung cancer screening are cost-effective and should be integrated so that treatment is initiated during screening visits. This is likely to reduce overall costs to the health service, and wider integrated care systems, improve quality and length of life, and may lessen health inequalities.

The authors have declared no competing interest.

York Health Economics Consortium (YHEC) were funded by the Manchester University NHS Foundation Trust (MFT) to develop the economic model. Funding was provided from AstraZeneca, through a small grant application, to MFT to complete this study. AstraZeneca had no input into the design of the study, the evaluation, interpretation, writing or conclusions of this manuscript.

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