Predictive Value of Serum Uric Acid Levels on Mortality in Acute Coronary Syndrome Patients with Chronic Kidney Disease after Drug-Eluting Stent Implantation

Abstract

Objectives: Despite optimal treatments, prognosis in acute coronary syndrome (ACS) patients with chronic kidney disease (CKD) remains poor. Elevated serum uric acid (SUA) levels may predict worse outcomes in these patients. The objective was to assess the predictive value of SUA levels on mortality in ACS patients with CKD after drug-eluting stent (DES) implantation. Methods: We retrospectively assessed ACS patients with CKD who underwent successful DES implantation between January 2007 and December 2009. Patients were followed up from January to March 2012. CKD was defined as an estimated glomerular filtration rate <60 ml/min/1.73 m². We assessed the association between SUA levels and mortality. Results: A total of 1,132 patients were included. The mean age was 67.7 years. During a mean follow-up of 38.5 months, 145 patients died: 50 from cardiac diseases, 28 from cerebral diseases, 14 from renal diseases and 53 from other causes. After adjustment for confounders, SUA levels increased the risk of all-cause, cerebral and other-cause mortality. Adjusted hazard ratios for quartiles 3 and 4 versus quartile 1 of SUA were: all-cause, 1.66 [95% confidence interval (CI) 1.08-2.78] and 1.99 (95% CI 1.21-3.23); cerebral, 2.24 (95% CI 0.43-11.7) and 5.89 (95% CI 1.30-26.6); and other causes, 2.81 (95% CI 1.17-6.78) and 3.89 (95% CI 1.63-9.29), respectively. SUA levels had no impact on cardiac and renal mortality rates. Conclusions: High SUA levels are associated with all-cause, cerebral and other-cause mortality rates in ACS patients with CKD after DES implantation. Future research is needed to determine if lowering SUA levels will decrease mortality in these patients.