N-acetylcysteine does not prevent contrast induced nephropathy after cardiac catheterisation with an ionic low osmolality contrast medium: a multicentre clinical trial.

OBJECTIVE To evaluate oral N-acetylcysteine in the prevention of contrast induced nephropathy (CIN) in patients at low to moderate risk undergoing cardiac catheterisation with ionic low osmolality contrast medium. METHODS In a multicentre double blind clinical trial 156 patients undergoing coronary angiography or percutaneous coronary intervention with serum creatinine > or = 106.08 micromol/l or creatinine clearance < 50 ml/min or diabetes mellitus were randomly assigned to receive N-acetylcysteine 600 mg orally twice daily for two days or placebo. Only low osmolality ionic contrast medium was used. RESULTS Sixteen patients developed CIN, defined as an increase of 44.2 micromol/l in creatinine in 48 hours: eight of 77 patients (10.4%) in the N-acetylcysteine group and eight of 79 patients (10.1%) in the placebo group (p = 1.00). The mean (SD) change in serum creatinine was similar in both groups: 7.96 (35.36) micromol/l in the N-acetylcysteine group and 6.19 (25.64) micromol/l in the placebo group (p = 0.67). No difference was observed in the change in endogenous creatinine clearance (-0.54 (10.4) ml/min v -2.52 (12.3) ml/min, N-acetylcysteine and placebo, respectively, p = 0.28). CONCLUSION Oral N-acetylcysteine did not prevent CIN in patients at low to moderate risk undergoing cardiac catheterisation with ionic low osmolality contrast medium.