Predictors of long-term abstinence rate by income level in the Korean smoking cessation programme

To assess whether predictors of success in stopping smoking vary as a function of income level in Korean smoking cessation services.

Prospective study of predictors of smoking cessation up to 6 months' follow up.

A sample of 954 people (mean age 49.13 ± 10.69 years; 863 [90.5%] men) enrolled in the Korean National Health Insurance Service smoking cessation programme in 2015.

The outcome measure was self-reported continuous abstinence up to 6-month follow up. Predictors were income and other sociodemographic variables as well as smoking-related variables measured at baseline.

The continuous 6-month abstinence rate was 30.5%. The adjusted odds of 6-month continuous abstinence were lower among low-income versus the middle- or high-income smokers (OR, 0.54; 95% CI, 0.35-0.84), those with severe versus light/moderate cigarette dependence (OR, 0.72; 95% CI, 0.52-0.98), and use of bupropion versus varenicline (OR, 0.60; 95% CI, 0.39-0.91). The association between cigarette dependence and outcome was only present among low-income smokers.

Lower income, higher cigarette dependence, and choice of bupropion versus varenicline are associated with lower chances of stopping smoking in Korean smoking cessation services, but the association with cigarette dependence is only found in low-income smokers.