Effect of statin on long-term outcomes in persistent tobacco users receiving percutaneous coronary intervention: A longitudinal, retrospective cohort study

Abstract

The role of statins in improving cardiovascular outcomes is well established, but little is known about their impacts on long-term outcomes in persistent tobacco users with stable coronary artery disease (CAD) who receive percutaneous coronary intervention (PCI). A population of persistent smokers with CAD treated by PCI was analyzed. From 2012 through 2019, a cohort of 907 persistent tobacco users with stable CAD undergoing PCI were enrolled from the inpatient department of Taichung Tzu Chi Hospital, Taiwan. We surveyed statin users and non-statin users after index PCI, and general characteristics, major risk factors, angiographic findings, and long-term clinical outcome were compared. Kaplan-Meier curve was used to compare the survival difference and Cox proportional hazard model was used to analyze the predictors for all-cause mortality and major adverse cardiovascular events, including cardiovascular (CV) mortality, myocardial infarction, and repeated PCI procedures. The statin group had a higher average total cholesterol (P < .01) and low-density lipoprotein cholesterol (LDL-C) level (P < .01) and was younger (P < .01) than the non-statin group. Ninety-six point one percent patients in the statin group had a LDL-C level below 100 mg/dL after treatment. They also had a more frequent history of acute coronary syndrome and lower prevalence of chronic kidney disease than the non-statin group (both P < .01). Freedom from all-cause and CV mortality were lower in the non-statin group than the statin group (both P < .01). After adjustment for age and chronic kidney disease, statin treatment no longer reduced the risk of CV mortality (hazard ratio: 0.32, 95% confidence interval = 0.07-1.49), but was still associated with a reduction in all-cause mortality (hazard ratio: 0.27, 95% confidence interval = 0.10-0.75). In persistent tobacco users undergoing PCI, patients treated with statin for LDL-C values above 100 mg/dL had a similar level of cardiovascular protection as those with LDL-C below 100 mg/dL and without statin treatment. Therefore, smoking attenuates pleiotropic effect of statin. Nevertheless, statin therapy was still associated with a reduction of all-cause mortality.