Struggling to make ends meet: exploring pathways to understand why smokers in financial difficulties are less likely to quit successfully.

Background: In high-income countries, those with low-to-middle incomes have been observing stagnating median wages and marginal improvements in their living standards. Smokers in financial difficulties appear to be less likely to quit smoking. Understanding the reasons for this is essential to intervening to improve cessation outcomes in this population, and reduce smoking-related health inequalities.
Methods: We used longitudinal data from Waves 4 to 7 of the ITC Four Country Survey (ITC-4), and included those with data from at least two consecutive waves. Associations between financial difficulties and making a quit attempt, and quit success were analysed using generalised estimating equations, with adjustment for confounders. Mediation analysis was conducted to identify potential mediators of the observed effects of financial difficulties on cessation outcomes.
Results: Having financial difficulties had little impact on making quit attempts (adjusted OR 0.84, 95% CI 0.70-1.01). Smokers with financial difficulties were substantially less likely to succeed at quitting (adjusted OR 0.55, 95% CI 0.39-0.76); an effect which was consistent over the survey years. Among the potential mediators examined, those relating to cognition of health-related and quality of life-related consequences of smoking were the most important mediators, though the proportion of the effect mediated by the largest mediator was small (6.8%).
Conclusion: Having financial difficulties remains an important barrier to smokers achieving quit success. This effect does not appear to be due to anticipated factors such as reduced use of cessation services or treatment. Further research is required to determine strong mediators of the financial difficulties effect on quit success and to tailor more effective cessation programmes.