Effects of Statin Intensity on Long-term Outcomes After Coronary Artery Bypass Grafting

Abstract

BackgroundThe current study sought to investigate the association between statin intensity and long-term clinical outcomes according to initial clinical presentation after coronary artery bypass grafting (CABG). MethodsThe 6531 patients who underwent CABG included in this study were classified into 4 groups according to statin intensity: 731 in the no or low statin group (atorvastatin <10 mg), 2310 in the lower-moderate group (atorvastatin 10-mg equivalent), 2404 in the higher-moderate group (atorvastatin 20-mg equivalent), and 1086 in the high-intensity group (atorvastatin ≥ 40-mg equivalent). The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE) at 5 years. Multivariate Cox and inverse probability weighting methods were performed to adjust for baseline differences. ResultsAt least moderate-intensity statin use was associated with significantly lower risk of 5-year MACCE compared with no or low-intensity statin use (hazard ratio [HR], 0.694; 95% confidence interval [CI], 0.493-0.977; P = .036). Among patients who were taking at least a moderate-intensity statin, both higher-moderate intensity (HR, 0.622; 95% CI, 0.479-0.807; P < .001) and high-intensity statin (HR, 0.613; 95% CI, 0.421-0.894; P = .011) groups showed significantly lower risks of MACCE than the lower-moderate intensity statin group at 5 years after CABG. There was no significant difference in the risk of MACCE between higher-moderate intensity and high-intensity statin groups (HR, 0.987; 95% CI, 0.661-1.475; P = .950). Multivariable Cox and inverse probability weighting methods yielded similar results. In a subgroup analysis compared with the use of a lower-moderate intensity statin, the use of a higher-moderate or high-intensity statin (equivalent dose with atorvastatin ≥20 mg) was associated with a significantly lower risk of MACCE among CABG patients who presented with acute coronary syndrome but not in those who presented with stable ischemic heart disease (interaction P = .001). ConclusionsThe use of a lower-moderate intensity statin (atorvastatin 10-mg equivalent) was associated with relatively poorer long-term clinical outcomes than the use of higher-moderate or high-intensity statin, especially in acute coronary syndrome patients after CABG.