Introduction: Most smokers have a history of unsuccessful quit attempts. This study used data from 7 waves (2002-2009) of the International Tobacco Control 4-country cohort study to examine the role of smokers' quitting history (e.g., recency, length, and number of previous quit attempts) on their subsequent likelihood of making a quit attempt and achieving at least 6 months of sustained abstinence.
Methods: Generalized estimating equations were used, allowing for estimation of relationships between variables across repeated observations while controlling for correlations from multiple responses by the same individual (29,682 observations from 13,417 individuals).
Results: The likelihood of a future quit attempt increased independently with recency and number of prior attempts. By contrast, the likelihood of achieving sustained abstinence of at least 6 months was reduced for smokers with a failed quit attempt within the last year (15.1% vs. 27.1% for those without, p < .001). Two or more failed attempts (vs. only one) in the previous year were also associated with a lower likelihood of achieving sustained abstinence (OR: 0.57, 95% CI: 0.38-0.85). Effects persisted after controlling for levels of addiction, self-efficacy to quit, and use of stop-smoking medications.
Conclusions: There appears to be a subset of smokers who repeatedly attempt but fail to remain abstinent from tobacco. Understanding why repeated attempts might be less successful in the long term is an important research priority because it implies a need to tailor treatment approaches for those who are motivated to quit but persistently relapse back to smoking.