Impact of diabetes mellitus in patients undergoing contemporary percutaneous coronary intervention: Results from a Korean nationwide study

Objectives Despite an obvious improvement in the treatment of coronary artery disease (CAD) and survival rate of patients with CAD during recent decades, diabetes mellitus (DM) is still considered a risk factor of adverse clinical outcomes in these patients. Therefore, we sought to evaluate the clinical implications of DM in patients with CAD who underwent contemporary percutaneous coronary intervention (PCI). Methods Based on the National Health Insurance claims data in South Korea, patients aged 18 years or older who had undergone PCI for the diagnosis of CAD between 2011 and 2015 were analyzed. Patients were classified into the DM (n = 26,872) and non-DM (n = 54,243) groups. The primary endpoint was all-cause mortality, and it was compared between the two groups via a propensity score matching analysis. Results The study population was categorized as patients with angina (n = 49,228) or acute myocardial infarction (AMI, n = 31,887). The study population had a median follow-up of 2.1 years (interquartile range, 1.1–3.2). After the propensity score matching analysis, 8,157 and 4,266 pairs of patients with angina and AMI were identified, respectively. In the matched angina group, the incidence of all-cause death was significantly higher in patients with DM (adjusted hazard ratio [aHR]: 1.30; 95% confidence interval [CI]: 1.16–1.47; p<0.001) than in those without DM. Moreover, in the matched AMI group, the incidence of all-cause death was significantly higher in patients with DM (aHR: 1.35; 95% CI: 1.19–1.53; p<0.001) than in those without DM. Conclusions In patients undergoing contemporary PCI in Korea, the presence of DM was associated with poorer clinical outcomes.