Effectiveness of pharmacotherapy for smoking cessation: Umbrella review and quality assessment of systematic reviews

Abstract Background: In the long term, smoking cessation can decrease the risk of cancer, stroke, and heart attacks and improve overall survival. This umbrella review aimed to assess the effect of pharmacological interventions on smoking cessation and to evaluate the methodological quality of previously conducted systematic reviews. Methods: Databases including the Cochrane library, PubMed, MEDLINE, EMBASE, CINAHL, PsycINFO, Web of Science, Scopus and Google Scholar were used to retrieve reviews. Systematic reviews that included only randomized controlled trials designed to assess pharmacotherapeutic interventions supporting abstinence from smoking were considered in this umbrella review. The methodological quality of the included reviews was assessed using the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) tool, which contains 16 domains. Two authors (AM, AB) screened the titles and abstracts of all reviews obtained by the search strategy, assessed the full text of selected articles for inclusion and extracted data independently. Two authors (AM, AB) also performed a quality appraisal independently. The findings of the studies were narrated qualitatively to describe the evidence regarding the effectiveness of pharmacotherapies for smoking cessation.Results: Ten reviews were included in this umbrella review. Most of the reviews included in this review reported that Nicotine Replacement Therapy (NRT), bupropion and varenicline and cytisine were effective for smoking cessation. The combination of a nicotine patch with other nicotine formulations was also more effective than monotherapy. Similarly, the combination of nicotine with the non-nicotine therapy varenicline was found to be more effective than varenicline alone. However, the opioid antagonist naltrexone alone was not found to be effective for smoking cessation nor in combination with nicotine replacement therapy. Based on the AMSTAR 2 rating, one review scored high quality, two scored moderate quality, four scored low quality, and three scored critically low quality.Conclusions: This review revealed that drugs approved by the US Food and Drug Administration (FDA) are effective for smoking cessation. A combination of nicotine patches with other nicotine formulations was also effective for smoking cessation compared to nicotine monotherapy. Systematic review registration: PROSPERO Registration: CRD42017080906