Contrast-induced nephropathy (CIN) is associated with high morbidity and mortality. The recent literature contains numerous clinical trials with similar design, endpoints, and patient populations, describing the nephrotoxic effects of various
contrast agents, which are higher with ionic vs. nonionic
contrast agents. The difference in the incidence of CIN with nonionic
contrast agents may be due to the number of
benzene rings (monomer vs. dimer),
iodine content, osmolality, and viscosity of the individual
contrast agents. We evaluated the recently published data from clinical studies with nonionic iodinated
contrast agents in patients with preexisting
chronic renal insufficiency (CRI) and report the results of pooled analysis of data from recent prospective independent studies of CIN with various nonionic
contrast agents. Review of the recent literature revealed that the CIN incidence varies across the studies reviewed and the
contrast agents used. The highest incidence of CIN was observed in studies using
iohexol or
ioxilan. Results of the pooled analysis of nonionic
contrast agents (with more than one randomized study) showed a similar incidence of CIN after
iodixanol and
iopamidol in patients with preexisting CRI, while both agents showed a significantly lower incidence of CIN compared to
iohexol. Since
iodixanol is more expensive than
iopamidol, this observation may be clinically relevant.