Friday, December 18, 2009
Chronic kidney disease (CKD) is a risk factor for poor outcomes in patients with coronary artery disease (CAD), but it is unknown whether CKD influences the efficacy of alternative CAD treatment strategies. Thus, we compared outcomes in stable CAD patients with and without CKD randomized to percutaneous coronary intervention (PCI) and optimal medical therapy (OMT) or OMT alone in a post hoc analysis of the 2,287 patient COURAGE study. At baseline, 320 patients (14%) had CKD defined as a glomerular filtration rate of <60 mL/min/1.73 m2, as estimated by the abbreviated 4-variable Modification of Diet in Renal Disease equation. The patients with CKD were older (68 ± 9 vs 61 ± 10 years; p <0.001) and more often had diabetes mellitus (42% vs 33%; p = 0.002), hypertension (81% vs 65%; p <0.03), heart failure (13% vs 3.4%; p <001), and three-vessel CAD (37% vs 29%, p = 0.01). After adjustment for these differences, CKD remained an independent predictor of death or nonfatal myocardial infarction (hazard ratio 1.48, 95% confidence interval 1.15 to 1.90). PCI had no effect on these outcomes. Furthermore, at 36 months, a similar percentage of patients with CKD treated with OMT (70%) and PCI plus OMT (76%) were angina free compared to patients without CKD. In conclusion, CKD is an important determinant of clinical outcomes in patients with stable CAD, regardless of the treatment strategy. Although PCI did not reduce the risk of death or myocardial infarction when added to OMT for patients with CKD, it also was not associated with worse outcomes in this high-risk group.