Effectiveness of smoking cessation interventions among persons with cancer: A systematic review

Objectives: Continued smoking after cancer diagnosis is associated with worse outcomes, however, many persons diagnosed with cancer who smoke are unable to quit successfully. Effective interventions are needed to promote quitting in this population. The purpose of this systematic review is to understand the most effective interventions for smoking cessation among persons with cancer and to identify gaps in knowledge and methodology to suggest directions for future research. Methods: Three electronic databases (The Cochrane Central Register of Controlled trials, MEDLINE, and EMBASE) were searched for studies of smoking cessation interventions among persons with cancer, published up to 1 July 2021. Title and abstract screening, full-text review, and data extraction was completed by two independent reviewers, via Covalence software, with any discordance resolved by a third reviewer. A quality assessment was completed using the Cochrane Risk of Bias Tool Version 2. Results: Thirty-six articles were included in the review, including 17 randomized-controlled trials (RCTs) and 19 non-RCT studies. Of the 36 studies, 28 (77.8%) utilized an intervention that included both counseling and medication, with 24 (85.7%) providing medication to participants at no cost. Abstinence rates in the RCT intervention groups (n = 17) ranged from 5.2% to 75%, while the non-RCTs found abstinence rates ranging from 15% to 46%. Overall, studies met a mean of 2.28 out of seven quality items, ranging from 0 to 6. Conclusions: Our study highlights the importance of utilizing intensive combined behavioral and pharmacological interventions for persons with cancer. While combined therapy interventions seem to be the most effective, more research is needed, as current studies have several quality issues, including the lack of biochemical verification for abstinence.