Iodixanol, an isosmolar contrast medium, shows lower incidence of elevated serum creatinine (SCr) or decreased glomerular filtration rate (GFR) than iopromide, according to a study published in the July issue of Radiology.

The study, conducted by a team of physicians and researchers at the Medical University of South Carolina, sought to determine the effects of iso-osmolality contrast medium compared with a low-osmolality agent on renal function SCr and GFR in high-risk patients undergoing intravenous contrast material–enhanced CT.

All 117 patients with decreased renal function, defined as SCr>1.5 mg/mL or GFR<60mL/minute, underwent contrast-enhanced CT. Sixty-one patients were administered iodixanol, while 56 were administered iopromide. The study measured changes in SCr levels and GFR at plus one, two and three days post-CT and then their outcomes were monitored at 30 and 90 days.

Fewer patients administered iodixanol showed an SCr increase of 25 percent or greater, 8.5 percent vs. 28 percent respectively. No patients in either group showed a contrast media related adverse event at the 30- or 90-day follow-up. There was a clinically-relevant GFR reduction of 5mL/min in significantly more patients in the iopromide group than in the iodixanol group; 42.3 percent vs. 24.1 percent.

The study concluded that while “intravenous contrast material application in high-risk patients is unlikely to be associated with permanent adverse outcomes, SCr levels after contrast material administration are lower in the iodixanol group than in the iopromide groups.”

The authors noted their findings may differ from other recently published studies on the topic. They wrote that their “systematic serial assessment of SCr level and GFR over three days after CM [contrast media] administration may have been more sensitive to detect SCr-level changes compared with the single sampling at a variable interval (48-72 hours) after contrast medium administration in the prior investigation.”

The researchers concluded the since in most patients with decreased renal function, “the SCr will peak in the first 72 hours after CM administration, multiple measures may provide greater accuracy regarding SCr dynamics.”

GE Healthcare provided support for the study.