Evaluation of N-acetylcysteine for the prevention of contrast-induced nephropathy

BACKGROUND Contrast-induced nephropathy (CIN) remains a leading cause of acute renal failure in hospitalized patients. N-Acetylcysteine has been studied previously for the prevention of CIN, resulting in mixed findings. OBJECTIVE The objective of this study was to determine the impact of N-acetylcysteine on the development of CIN in order to guide its use at community, teaching hospitals. METHODS Patients admitted between January 1 and December 31, 2011, receiving intravenous radiocontrast dye were included if they were compliant with two or more of the following conditions: baseline serum creatinine >1.2 mg/dL or estimated creatinine clearance <50 mL/min, age ≥75 years, diabetes mellitus, heart failure, or hypertension. The primary outcome was the difference in the proportion of patients in each group (N-acetylcysteine or no N-acetylcysteine) who developed CIN, which was defined as a ≥0.5 mg/dL increase in serum creatinine or a ≥25% increase in serum creatinine within 12-96 hours post-exposure to contrast. RESULTS A total of 302 patients were included, 151 who received N-acetylcysteine and 151 who did not receive N-acetylcysteine. Patients who received N-acetylcysteine had significantly worse renal function at baseline than those who did not receive N-acetylcysteine (mean pre-contrast serum creatinine, 1.41 vs. 0.95 mg/dL, p<0.0001). A lower proportion of patients developing CIN was observed between those who received N-acetylcysteine and those who did not receive N-acetylcysteine (10.2% vs. 21.8%, p=0.0428). CONCLUSIONS The use of N-acetylcysteine was likely associated with a reduced incidence of CIN in patients at risk for CIN development. Based on these results, hospitals may benefit from the development of a protocol to guide the appropriate use of N-acetylcysteine.