N-Acetylcysteine for the Prevention of Contrast-induced Nephropathy

A Systematic Review and Meta-analysis

Authors

  • Raymond Liu MD,

    1. Department of Medicine, University of California, San Francisco, CA, USA
    2. Veterans Affairs PRIME Program
    Search for more papers by this author
  • Deepu Nair MD,

    1. Department of Medicine, University of California, San Francisco, CA, USA
    2. Veterans Affairs PRIME Program
    Search for more papers by this author
  • Joachim Ix MD,

    1. Department of Medicine, University of California, San Francisco, CA, USA
    2. Department of Medicine, San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
    Search for more papers by this author
  • Dan H. Moore PhD,

    1. Research Institute, California Pacific Medical Center, San Francisco, CA, USA
    2. Department of Epidemiology and Biostatistics
    Search for more papers by this author
  • Stephen Bent MD

    1. Department of Medicine, University of California, San Francisco, CA, USA
    2. Department of Medicine, San Francisco Veterans Affairs Medical Center, San Francisco, CA, USA
    3. Osher Center for Integrative Medicine, University of California, San Francisco, CA, USA.
    Search for more papers by this author

Address correspondence and requests for reprints to Dr. Liu: San Francisco VA Medical Center, 111-A1, 4150 Clement Street, San Francisco, CA 94121 (e-mail: rliu3@yahoo.com).

Abstract

Objective: Contrast-induced nephropathy is a common cause of acute renal failure in hospitalized patients. Although patients are often given N-acetylcysteine to prevent renal injury from contrast agents, there are no clear guidelines supporting its use. We conducted a systematic review to determine whether administering N-acetylcysteine around the time of contrast administration reduces the risk of contrast-induced nephropathy.

Design: We searched MEDLINE, EMBASE, the Cochrane Collaboration Database, bibliographies of retrieved articles, and abstracts of conference proceedings, and consulted with experts to identify relevant studies. Randomized controlled trials of N-acetylcysteine in hospitalized patients receiving contrast were included. Studies were excluded if they did not report change in creatinine or incidence of contrast-induced nephropathy at 48 hours.

Measurements And Main Results: Nine randomized controlled trials satisfied all inclusion criteria and were included in the analysis. The difference in mean change in creatinine between the N-acetylcysteine-treated group and controls was −0.27 mg/dl (95% confidence interval [CI], −0.43 to −0.11). The relative risk of developing contrast-induced nephropathy was 0.43 (95% CI, 0.24 to 0.75) in subjects randomized to N-acetylcysteine. Significant heterogeneity existed among studies, suggesting differences in patient populations or study methodology not identified by sensitivity analyses. The incidence of dialysis was rare (0.2%).

Conclusions: Our findings suggest that N-acetylcysteine helps prevent declining renal function and contrast-induced nephropathy. While N-acetylcysteine is inexpensive and nontoxic, undeviating insistence for dosing at least 12 hours in advance of contrast exposure may delay diagnostic and therapeutic procedures. Future studies are needed to address the longer-term clinical outcomes and cost-effectiveness of this agent.

Ancillary