Effect of N-Acetylcysteine on Serum Creatinine Concentration in Patients with Chronic Renal Insufficiency Who Are Undergoing Coronary Angiography

Background: Prior studies have produced conflicting results on whether N-acetylcysteine (NAC) reduces the incidence of contrast-induced nephropathy (CIN) in patients undergoing coronary angiography (CA). The dosing regimens of NAC in these studies seemed impractical for everyday clinical practice. Objective:We studied the effect of NAC, with a novel dosing strategy, on serum creatinine concentration (SCr), and the incidence of CIN, in patients who were undergoing CA and/or percutaneous coronary intervention (PCI). Methods: Twenty-five subjects with baseline renal insufficiency who were undergoing CA and/or PCI were randomized to either NAC or placebo.The treatment schedule was 800 mg of NAC 12 h prior to angiography, 600 mg of NAC 2 h prior to angiography, and 600 mg of NAC 6 h after angiography or matching placebo. All subjects were hydrated with 1 ml/kg of 0.45% saline and received non-ionic contrast for angiography. The primary endpoint was change in SCr and the secondary endpoint was the incidence of CIN as defined by an increase of 0.5 mg/dl or 25% in SCr at 48 h. Results:The average SCr at enrollment was 1.7 mg/dl and average dye exposure was 171 ml. The average change in SCr in the NAC and placebo groups was 0.14 and 0.06 mg/dl, respectively (p = 0.60). The incidence of CIN was 18 and 14% in the NAC and placebo groups, respectively (p = 1.0). Conclusion: In this small study, there was no significant difference in the change inSCr nor the incidence of CIN in patients with baseline renal insufficiency undergoing CA and/or PCI who were treated with NAC or placebo.