Long-Term Benefit and Withdrawal Effect of Statins After Percutaneous Coronary Intervention: A Nationwide Population-Based Cohort Study

PURPOSE: Despite indubitable evidence for the cardiovascular benefits of statins, there have been concerns that statin discontinuation may cause negative effects known as "statin withdrawal syndrome." This study aimed to assess the benefit and the withdrawal effect of statins after percutaneous coronary intervention (PCI). PATIENTS AND METHODS: We conducted a retrospective cohort study on 5218 patients who underwent PCI between 2002 and 2013 using the nationwide health insurance claim data in Korea. Based on the prescription data, the use of statins during follow-up was classified into three risk periods: "statin period" (period with statin cover), "statin withdrawal period" (withdrawal of statin within 30 days), and "no statin period" (no exposure to statin for longer than 30 days). The primary outcome was the composite outcome of myocardial infarction, coronary revascularization, stroke, and all-cause death. We performed multivariate Cox proportional regression analyses which treated the use of statins as a time-dependent variable. RESULTS: During the follow-up period of 3.54 ± 2.91 years (mean ± standard deviation), 1515 (29.0%) patients sustained a primary outcome. Compared with the "no statin period," the "statin period" was associated with lower risk of the primary outcome (adjusted hazard ratio [HR] 0.72, 95% confidence interval [CI, 0.63-0.81]). While the "statin withdrawal period" posed a significantly increased risk (adjusted HR 1.87, 95% CI [1.52-2.29]). With respect to the intensity of statins associated with withdrawal, dose-dependent increased risk was observed for withdrawal of low-, moderate-, and high-intensity statins; adjusted HR [95% CI] were 1.45 [0.74-2.86], 1.86 [1.49-2.32], and 2.61 [1.41-4.81], respectively. CONCLUSION: After PCI, there was an increased cardiovascular risk during the statin withdrawal period, especially with the use of high-intensity statins. To maximize the beneficial effect and to avoid the withdrawal effect of statins, high-risk patients need to adhere to taking statins without discontinuation.