Beyond "Safe and Effective": The urgent need for high-impact smoking cessation medications.

Smoking cessation medications (SCMs) are an evidence-based cornerstone of comprehensive tobacco control programs globally. However, the impact of SCMs on population smoking prevalence is controversial, with inconsistencies between randomized controlled trials (RCTs) and population-based observational studies. We estimated SCM impact on permanent cessation and population smoking prevalence by extrapolating efficacy estimates from meta-analyses of RCTs, using the standard population impact formula: efficacy*reach. We calculated the potential SCM impact under a range of assumptions for permanent cessation (20%,14%), behavioral support (yes/no), reach (40%-2%), and underlying smoking prevalence. Assuming behavioral support for all, depending on reach, 8%-0.3% of smokers are expected to quit permanently. Without behavioral support, permanent cessation is estimated to be 6.4%-0.2%. Assuming an underlying population smoking prevalence of 14%, (current U.S. prevalence), the maximum impact on population smoking prevalence is 1.12%. Impact on prevalence increases with increasing underlying country-specific levels of prevalence. With current U.S. levels of reach, behavioral support and smoking prevalence, we estimate that, based on a single course of treatment, 2.3% of smokers would quit permanently, contributing to a 0.3% decrease in population level smoking prevalence. Even under ideal conditions, the potential of current first-line SCMs to increase cessation in a substantial proportion of smokers, and reduce population smoking prevalence, is limited. In order to avert the predicted billion tobacco-caused deaths in this century, "safe and effective" medications are not sufficient: SCMs with high population impact are urgently needed. Policies to ensure the availability and accessibility of highly efficacious SCMs, with behavioral support, are crucial.

Diminishing benefit of smoking cessation medications during the first year: a meta-analysis of randomized controlled trials.

BACKGROUND AND AIMS: Although smoking cessation medications have shown effectiveness in increasing abstinence in randomized controlled trials (RCTs), it is unclear to what extent benefits persist over time. This paper assesses whether the benefits of smoking cessation medications decline over the first year. METHODS: We selected studies from three systematic reviews published by the Cochrane Collaboration. RCTs of first-line smoking cessation medications, with 6- and 12-month follow-up, were eligible for inclusion. Meta-analysis was used to synthesize information on sustained abstinence (SA) at 6 versus 12 months and 3 versus 6 months, using the risk difference (RD) ('net benefit') between intervention and control group quit rates, the relative risk (RR) and the odds ratio (OR). RESULTS: Sixty-one studies (27 647 participants) were included. Fewer than 40% of intervention group participants were sustained abstinent at 3 months (bupropion: 37.1%; nicotine replacement therapy (NRT): 34.8%; varenicline: 39.3%); approximately a quarter were sustained abstinent at 6 months (bupropion: 25.9%; NRT: 26.6%; varenicline: 25.4%), and approximately a fifth were sustained abstinent at 12 months (bupropion: 19.9%; NRT: 19.8%%; varenicline: 18.7%). There was only a small decline in RR (3 months: 1.95 [95% confidence interval (CI) = 1.74-2.18, P < 0.0001]; 6 months: 1.87 (95% CI = 1.67-2.08 P < 0.0001); 12 months: 1.75 (95% CI = 1.56-1.95, P < 0.0001) between intervention and control groups over time, but a substantial decline in net benefit [3 months: RD = 17.3% (14.5-20.1%); 6 months: RD = 11.8% (10.0-13.7%); 12 months: RD = 8.2% (6.8-9.6%)]. The decline in net benefit was statistically significant between 3 and 6 [RD = 4.95% (95% CI = 3.49-6.41%), P < 0.0001] and 6 and 12 months [RD = 3.00% (95% CI = 2.36%-3.64%), P < 0.0001)] for medications combined and individual medications. CONCLUSIONS: The proportion of smokers who use smoking cessation medications who benefit from doing so decreases during the course of the first year, but a net benefit still remains at 12 months.