Cardiovascular Events Associated With Smoking Cessation Pharmacotherapies A Network Meta-Analysis

Stanford Prevention Research Center, Stanford University, Stanford, CA & University of Ottawa, Ottawa, Canada.
Circulation (Impact Factor: 14.43). 12/2013; 129(1). DOI: 10.1161/CIRCULATIONAHA.113.003961
Source: PubMed


Stopping smoking is associated with many important improvements in health and quality of life. Use of cessation medications is recommended to increase the likelihood of quitting. However, there is historical and renewed concern that smoking cessation therapies may increase the risk of cardiovascular disease (CVD) events associated within the quitting period. We aimed to examine whether the three licensed smoking cessation therapies: nicotine replacement therapy (NRT); bupropion, and; varenicline and were associated with an increased risk of CVD events using a network meta-analysis.
We searched ten electronic databases, and made communication with authors of published randomized clinical trials (RCT), and accessed internal US Food and Drug Administration (FDA) reports. We included any RCT of the 3 treatments that reported on CVD outcomes. Among 63 eligible RCTs involving 21 NRT RCTs, 28 bupropion RCTs and 18 varenicline RCTs, we found no increase in the risk of all-CVD events with bupropion (RR 0.98, 95% Confidence Intervals [CIs], 0.54-1.73) or varenicline (RR 1.30, 95% CI, 0.79-2.23). There was an elevated risk associated with NRT that was predominantly driven by less serious events (2.29, 95% CI, 1.39-3.82). When we examined major adverse cardiovascular events (MACE) events, we found a protective effect with bupropion (RR 0.45, 95% CI, 0.21-0.85) and no clear evidence of harm with varenicline (RR 1.34, 95% CI, 0.66-2.66) or NRT (RR 1.95, 95% CI, 0.26-4.30).
Smoking cessation therapies do not appear to raise the risk of serious CVD events.

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    • "Among all adults, 27% are current smokers [4]. Cigarette smoking increases the risk of circulatory disease and cancer of the lung or bronchus, urinary bladder, prostate, colon, rectum and pancreas, which can lead to death [5] [6]. Tobacco use kills approximately 5–6 million people annually worldwide and 69,000 people in Poland every year [7] [8]. "
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    • "However, Se has protective effects against oxidative stress induced by tobacco smoke. It can remove oxygen radicals and prevent free oxygen radical-induced cell damage and inhibit lipids peroxidation [5]. The mechanism behind this process is most likely related to the function of Se-dependent enzymes and selenoproteins. "

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