Efficacy And Safety Of Varenicline For Smoking Cessation:A Meta-analysis Of Randomized Controlled Trials

Objective:To evaluate of the efficacy and safety of varenicline for smoking cessation compared with placebo, nicotine replacement therapy or sustained-release bupropion.Methods:Systematic search of electronic databases (MEDLINE, EMBASE, Cochrane Central Register, Web of Science SCI and CNKI) from their inception to March2011. Reference lists of identified articles, recently published editorials, and reviews on the topic for further eligible trials also were searched. Randomized controlled trials or semi-trials compared varenicline with placebo, nicotine replacement therapy or sustained-release bupropion, and with a minimal follow-up of12months. All of data was pooled and analyzed using Stata software for Meta analysis.Results:retrieval literature collected1022reports in which1012were excluded and10were included. Ten trials involving6,375smokers were included in the meta-analysis. The pooled risk ratios (RR) for continuous abstinence was2.83(95%CI:2.20-3.63) at52weeks for varenicline (lmg BID) versus placebo. Varenicline seemed to be more effective in smokers with chronic obstructive pulmonary disease (RR,3.33) than smokers with cardiovascular diseases (RR,2.64) or health smokers (RR,2.52), non-Asian smokers than Asian smokers (2.98vs.1.94), elder smokers than younger smokers (2.87vs.2.52), female smokers than male smokers (2.98vs.1.94). The five predominant reported adverse events for varenicline compared to placebo were vomiting, nausea, abnormal dreams, constipation, and dysgeusia. There was no sufficient evidence that varenicline was associated with an increased risk of psychiatric side effects (RR,1.45,95%CI:0.90-2.32).Conclusions Varenicline therapy compared with placebo is associated with a favorable effect on smoking cessation at the end of52weeks. However, As a result of the research in the design of the analysis process there are still some deficiencies, the psychiatric adverse events related with varenicline should be further studied with more qualified study. People with preexisting mental illnesses should be prudently treatment with varenicline.