Effect of N-Acetylcysteine in Prevention of Contrast-Induced Nephropathy after Coronary Angiography

ABSTRACT

BACKGROUND AND OBJECTIVES: Contrast-induced nephropathy (CIN) is associated with increased morbidity and mortality in coronary angiography. Although the mechanism is unclear, N-acetylcysteine (NAC) is known to protect against CIN. Preliminary studies with NAC have found conflicting results for the prevention of CIN in patients undergoing coronary angiography. This study was designed to evaluate the efficacy and safety of NAC for the prevention of CIN in patients undergoing coronary angiography. SUBJECTS AND METHODS: 48 patients with chronic renal insufficiency (mean [+/-SD] serum creatinine concentration, 2.06+/-0.56 mg/dL), who were undergoing coronary angiography with a nonionic, low-osmolar contrast agent, were prospectively studied. Patients were randomly assigned to receive either the antioxidant, NAC (600 mg orally twice daily), and 0.45% saline intravenously (n=25), before and after administration of contrast agents, or saline only (n=23). The renal function parameters were assessed 48 hour before and after radiocontrast media administration. RESULTS: 14 of the 48 patients (29%) showed an increase in the 0.5 mg/dL serum creatinine concentration after 48 hours of contrast media administration 4 of the 25 patients in the NAC group (16%) and 10 of the 23 in the control group (43%; p=0.036; relative risk, 0.37; 95% confidence interval, 1.04 to 7.79). In the NAC group, the mean serum creatinine concentration insignificantly increased (p=0.54), from 2.2+/-0.8 to 2.3+/-0.9 mg/dL, after 48 hours of contrast media administration; whereas, in the control group, the mean serum creatinine concentration significantly increased (p=0.011), from 1.9+/-0.4 to 2.2+/-0.8 mg/dL. The absolute change in serum creatinine concentration was significantly greater in the control than the NAC group (p=0.044). CONCLUSION: Prophylactic oral administration of the antioxidant NAC, along with hydration, prevents the decrease in the renal function induced by a nonionic, low-osmolality contrast agent in patients with chronic renal insufficiency.