Probability and predictors of long-term smoking relapse among Chinese adult smokers: A longitudinal study

Numerous smokers attempt to quit smoking, but most cessation efforts prove unsuccessful. Scarce evidence exists regarding predictors of long-term relapse in China. This study aims to evaluate the probability of relapse and examine factors may contribute to relapse among Chinese adults. A dynamic cohort of 6,036 observations on 2,378 adult quitters was constructed from the China Family Panel Studies in 2010, 2012, 2014, 2016 and 2018. The life table method was employed to calculate the probability of relapse for long-term smoking abstinence. Multivariate complementary log-log survival models were developed to examine the predictors of smoking relapse. We found that the probability of relapse decreased as the duration of abstinence increased, with rates of 49.07 %, 20.05 %, 10.29 %, and 6.63 % at 2, 4, 6, and 8 years of abstinence, respectively. The cumulative probability of relapse within 8 years was 65.89 %. Age ≥65 years, higher educational attainment, respiratory disease, and a satisfying lifestyle were associated with a reduced likelihood of relapse. Conversely, higher occupational prestige, alcohol drinking, cohabitant smoking, and greater future confidence were associated with an increased risk of relapse. These findings demonstrated that the probability of relapse decreased progressively over time, with most relapses occurring in the initial two years following quit attempts. Predictors of Chinese quitters' relapse behavior in our study were similar to those in previous studies. Drinking and cohabitant smoking were identified as strong predictors of relapse in this population.