Association of smoking with restenosis and major adverse cardiac events after coronary stenting: A meta-analysis

Background and Objective: The association between smoking and clinical outcomes after coronary stenting is controversial. The aim of this meta-analysis was to assess the association between smoking and in stent restenosis (ISR), major adverse cardiac events (MACE), or major adverse cardiac and cerebrovascular events (MACCE) after coronary stenting. Methods: A search for studies published before December 2014 was conducted in PubMed, Embase, and Cochrane library. An inverse random weighted meta-analysis was conducted using logarithm of the odds ratio (OR) and its standard error for each study. Results: Ten studies investigated the association between smoking and ISR. Overall, smoking was not associated with ISR (OR: 1.05, 95% CI: 0.79–1.41; I2 = 47.8%). Subgroup analysis also failed to show a significant association between smoking and ISR risk regardless of bare metal stent (BMS) and drug-eluting stent (DES) implantation. Eight studies explored the association between smoking and MACE, but no association was found (OR: 0.92, 95% CI: 0.77–1.10; I2 = 25.5%), and subgroup analysis revealed that no distinct difference was found between BMS and DES implantation. Three studies investigated the association between smoking and MACCE and significant association was found (OR: 2.09, 95% CI: 1.43–3.06; I2 = 21.6%). Conclusions: Our results suggest that in patients undergoing percutaneous coronary intervention with stent implantation, smoking is not associated with ISR and MACE; however, smoking is an independent risk factor for MACCE.