Abstract 4600: Long-Term Clinical Outcomes Following Drug-eluting and Bare Metal Stenting in Patients With Chronic Kidney Disease in Massachusetts
Background: Patients with chronic kidney disease (CKD) have been underrepresented in randomized trials of drug-eluting stents (DES) relative to bare metal stents (BMS) and are at high risk for mortality. We report a large consecutive series of patients with CKD followed 2 years after DES and BMS from a regional contemporary US practice with mandatory reporting.
Methods: All adults with CKD undergoing percutaneous coronary intervention (PCI) with stenting between April 1, 2003 and September 30, 2005 at all acute care non-federal hospitals in Massachusetts (MA) were identified from a state database that monitors the quality of cardiac care. The sample was restricted to MA residents to ensure endpoint ascertainment. According to index admission stent type(s), patients were classified as DES-treated if all stents were drug-eluting and BMS-treated if all stents were bare metal. Patients treated with both types of stents were excluded from the primary analysis. Two-year crude mortality risk differences (DES - BMS) were determined from vital statistics records, and risk-adjusted mortality, MI, and revascularization differences were estimated using propensity score matching of the patients with CKD, based on clinical, procedural, hospital, and insurance information collected at the index admission.
Results: 1749 patients with CKD (24% dialysis dependent) were treated with DES (n=1256) or BMS (n=493) during the study. Overall, 55% had diabetes mellitus, 37% had multivessel disease, and 67% presented with acute coronary syndromes. The overall 2 year mortality was 32.8% (unadjusted DES vs. BMS; 30.1% vs. 39.8%, p<0.001). After propensity score matching 431 BMS to 431 DES patients, the 2 year risk-adjusted mortality, MI, and revascularization rates were 39.4% vs. 37.4% (risk difference, 2.1%; 95% CI, −4.3% to 8.5%; p=0.52), 16.0% vs. 19.0% (risk difference, −3.0%; 95% CI, −8.2% to 2.1%; p=0.25), and 13.0% vs. 17.6% (risk difference, −4.6%; 95% CI, −9.5% to 0.3%; p=0.06).
Conclusions: Treatment of CKD patients with DES was associated with no difference in rates of mortality, MI at 2 years, and the difference in target vessel revascularization did not reach statistical significance compared with BMS.