A Propensity Score Matched Analysis of Statin Effects on Major Adverse Cardiac Events after Percutaneous Coronary Intervention in Patients Over 75 Years Old

OBJECTIVE: In an extremely aging society, it is beneficial to reconsider the value of medical treatment for extremely elderly patients. We therefore focused on the efficacy of statin therapy in extremely elderly patients. This study investigated the efficacy of statins for secondary prevention in patients over 75 years old. METHODS: This prospective multicenter registry included 1,676 consecutive extremely elderly patients with coronary artery disease who underwent successful percutaneous coronary intervention (PCI). The patients were followed up clinically for up to three years or until the occurrence of major adverse cardiac events (MACEs), defined as a composite of all-cause death and non-fatal myocardial infarction. Using propensity score methodology to eliminate selection bias, in a 1:1 matching ratio, we selected 466 pairs of patients for the analysis. RESULTS: During the median follow-up period of 25 months, MACEs occurred in 176 patients. The Kaplan-Meier analysis showed that statin treatment correlated with a lower probability of initial MACE occurrences within 30 days compared with no statin treatment (log-rank test, p<0.001). According to a landmark analysis at day 30, statin treatment still showed consistent effectiveness for reducing MACE occurrence during the follow up period (p=0.04). A multivariable Cox hazard analysis showed that statin therapy significantly reduced MACE occurrence (hazard ratio 0.55 [0.40-0.75], p<0.001). In the stratification analysis, statin therapy was especially beneficial in patients without symptomatic heart failure. CONCLUSION: Statins were effective in preventing MACEs in extremely elderly patients after PCI.