Impact of Chronic Kidney Disease on Utilization of Coronary Angiography and Percutaneous Coronary Intervention, and Their Outcomes in Patients With Non-ST Elevation Myocardial Infarction

Abstract

Chronic kidney disease (CKD) is an independent risk factor for cardiovascular disease. Coronary angiography (CAG) and percutaneous coronary intervention (PCI) are frequently performed in patients presenting with a non-ST elevation myocardial infarction (NSTEMI). Utilizing the National Inpatient Sample database, we assessed the trends in utilization of CAG, PCI, and coronary artery bypass grafting in 3,654,586 admissions with NSTEMI from 2001 to 2012. The rates of CAG were 54%, 36.1%, and 45.9%, respectively, in patients with normal renal function, patients with CKD not on renal replacement therapy (RRT), and patients with CKD requiring RRT. The in-hospital mortality for patients with NSTEMI was significantly higher in patients with CKD—3.9% in patients without CKD, 6.9% in CKD patients not on RRT, and 8.6% in CKD patients needing RRT. In a propensity-matched cohort of 126,740 NSTEMI admissions, CKD was associated with increased in-hospital mortality (7.9% vs 5.3%, p <0.001), acute kidney injury (34.3 % vs 10.6%, p <0.001), lower use of CAG (37.8% vs 46.4%, p <0.001), and PCI (16.2% vs 20.8, p <0.001), higher hospital costs ($17,333 vs $15,583, p <0.001), and a longer length of stay (6.8 days vs 5.5 days, p <0.001). PCI was associated with decreased mortality (odds ratio of 0.31 ± 0.01, p <0.001) in all the 3 groups. In conclusion, CKD is a marker of adverse outcomes in patients with NSTEMI. Although CAG and PCI were associated improved outcomes, they remain underutilized in these patients.