Effect of administration route on the renal safety of contrast agents: a meta-analysis of randomized controlled trials

Background: The objective of this study was to examine the association between administration route and relative renal safety of contrast agents. Methods: We searched all published articles indexed in Embase, Medline and the Cochrane Central Register of Controlled Trials, from January 1980 to November 2010, to identify relevant studies. Of the 1,047 initially identified studies, 11 randomized controlled trials (RCTs) including 2,210 patients with intra-arterial route and 7 RCTs including 919 patients with intravenous route were finally analyzed. Results: With regard to intra-arterial route, our meta-analysis showed that iodixanol significantly decreased the risk of contrast-induced acute kidney injury (CI-AKI) when compared with a pool of low-osmolar contrast media (LOCM; risk ratio [RR] = 0.68; 95% confidence interval [95% CI], 0.50-0.92; Z=2.47; p=0.01), with no significant heterogeneity between individual studies (p=0.14, 12=32.4%). However, iodixanol was not associated with a reduction in CI-AKI compared with the LOCM pooled together (RR=0.75; 95% CI, 0.44-1.26; Z=1.10; p=0.27) with intravenous application, again with no significant heterogeneity between individual studies (p=0.40, 12=3.6%). Conclusions: Our meta-analysis suggests that administration route may affect the renal safety of contrast agents. Specifically, iodixanol may be a better choice for patients in the interventional cardiology setting.