COMMENTARY

Statin Reduces Risk for Contrast-Induced AKI

Jeffrey S. Berns, MD

Disclosures

August 20, 2014

Editorial Collaboration

Medscape &

This feature requires the newest version of Flash. You can download it here.

Hello. This is Jeffrey Berns, Editor-in-Chief of Medscape Nephrology. The American Journal of Cardiology recently published a nicely done meta-analysis by Giacoppo and colleagues,[1] who looked at randomized controlled trials (RCTs) of statin therapy as a potential strategy for prevention of contrast-induced acute kidney injury (AKI) following coronary angiography.

This meta-analysis includes 8 RCTs; 4 were double-blinded trials and 4 were open-label trials in patients with some degree of renal dysfunction, albeit quite mild in some cases. The studies chosen for analysis compared a statin with either placebo or standard therapies, which could include N-acetylcysteine, IV sodium bicarbonate, or IV saline. They used a relatively liberal definition of AKI at 25% or greater increase in serum creatinine or an increase of 0.5 mg/dL or more within 72 hours.

For this analysis, they looked at patients who had a baseline glomerular filtration rate (GFR) < 60 mL/min/1.73 m2 and those with GFRs of ≥ 60 mL/min/1.73 m2. The largest and most recent of the individual studies, which was in a Chinese population, used a Modification of Diet in Renal Disease (MDRD)-calculated estimated GFR (eGFR), which raises its own issues, because I am not sure that that equation is very well validated in that particular patient population.

The patient populations were somewhat heterogeneous in terms of baseline renal function. Some were identified as having an initial creatinine < 1.5 mg/dL for entry, for example, while others included patients with eGFRs between 30 and 90 mL/min/1.73 m2.

The percentage of patients with diabetes varied in these studies. The largest and most recent study comprised only diabetics. In the other studies, about 20% to 40% of the patients were diabetic.

Overall Outcome Supports Preprocedure Statin Use

The overall outcome was quite interesting. There was a highly statistically significant 46% reduction in the relative risk for AKI in patients who received statins. The authors do not talk about other outcomes in terms of hospitalization, mortality, and so forth, but we all know what AKI does in terms of hospital mortality.

The overall incidence of AKI was just under 4% in the statin group across all of these studies and about 7% in the control population. Somewhat surprising, the effect of statins was more robust and much more statistically significant in the individuals who had higher eGFRs at baseline. Patients with eGFRs of ≥ 60 mL/min/1.73 m2 had a 60% reduction in AKI risk, whereas those with lower eGFR levels had a 33% reduction, which was only of borderline statistical significance. The type of statin, presence or absence of therapy with N-acetylcysteine, hydration, and so forth did not influence the results.

Of importance, the studies included were conducted in people who had not received statins before being injected with contrast; that is, this is not a study of people who were taking statins compared with those who were not taking statins for long periods of time. This was typically only preprocedural statin therapy. In the largest and most recent trial patients were given a statin for 2 days before and 3 days after the procedure. That particular study used rosuvastatin.

This study gives us something to think about. If there is time to begin a statin before a patient undergoes coronary angiography, it may be worth doing so before the patient is exposed to contrast, because it does appear from this meta-analysis that there is a significant reduction in the risk for AKI when statins are introduced before coronary angiography.

This is an interesting meta-analysis and the individual studies are themselves interesting. Many of them have been published in the cardiology literature rather than the renal literature, so it is worth taking some effort to look through that literature from time to time.

Thank you for listening. This is Jeffrey Berns, from the Perelman School of Medicine at the University of Pennsylvania in Philadelphia, and Editor-in-Chief of Medscape Nephrology.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....