Interventions for smoking cessation: An overview of Cochrane reviews

Evidence of different smoking cessation interventions varies and has been assessed in many Cochrane reviews. We conducted an overview of these Cochrane reviews to summarize the effects of current interventions for smoking cessation.

Nine databases were searched from their inception to October 2024, with no restrictions on language. Two authors independently extracted data from the same studies simultaneously, double checking after extraction. A second round of examination was conducted on all the extracted contents by another author. We employed a measurement tool to assess systematic reviews (AMSTAR-2) to evaluate the methodological rigor of the included systematic reviews (SRs), synthesized the GRADE results as reported, and conducted a narrative synthesis. The research protocol was registered on PROSPERO (CRD42023388884).

Seventy-one Cochrane reviews involving 3022 trials were included in this comprehensive analysis. The two predominant smoking cessation interventions were pharmacotherapy (24 SRs) and non-pharmacological therapy (31SRs). Overall, the methodological quality of all the reviews was good. Compared with placebo, the point effect size for each Cochrane review on relative risk (RR) regarding pharmacotherapies for prolonged abstinence rate ranged from 1.11 to 3.34, demonstrating high- or moderate-certainty evidence; whereas for non-pharmacological therapies, it varied from 0.79 to 25.38, but substantial heterogeneity was observed in most meta-analysis (I2>50%). Four studies investigating pharmacotherapies as interventions, adverse events were reported but no significant differences in outcomes were observed.

Pharmacotherapy demonstrated some efficacy in promoting prolonged abstinence rate, while the effectiveness of different non-pharmacological interventions for smoking cessation varied widely, highlighting the need for further research on the integration of pharmacotherapy and non-pharmacological therapies.