OBJECTIVES This study sought to compare the nephrotoxicity of iodixanol and ioxaglate in patients with renal impairment undergoing coronary angiography.

BACKGROUND Iodixanol, a nonionic, dimeric, iso-osmolar contrast medium (IOCM), may be less nephrotoxic than low-osmolar contrast media (LOCM) in high-risk patients.

METHODS In a prospective, randomized trial in 300 adults with creatinine clearance (CrCl) < or =60 ml/min, patients received either iodixanol or ioxaglate and underwent coronary angiography with or without percutaneous coronary intervention. The primary end point was the incidence of contrast-induced nephropathy (CIN) (an increase in serum creatinine [SCr] > or =25% or > or =0.5 mg/dl [> or =44.2 mumol/l]). The incidence of CIN in patients with severe renal impairment at baseline (CrCl <30 ml/min) or diabetes and in those receiving large doses (> or =140 ml) of contrast medium was also determined.

RESULTS The incidence of CIN was significantly lower with iodixanol (7.9%) than with ioxaglate (17.0%; p = 0.021), corresponding to an odds ratio (OR) of CIN of 0.415 (95% confidence interval [CI] 0.194 to 0.889) for iodixanol. The incidence of CIN was also significantly lower with iodixanol in patients with severe renal impairment (p = 0.023) or concomitant diabetes (p = 0.041), or in patients given > or =140 ml of contrast media (p = 0.038). Multivariate analysis identified use of ioxaglate (OR 2.65, 95% CI 1.11 to 6.33, p = 0.028), baseline SCr, mg/dl (OR 2.0, 95% CI 1.04 to 3.85, p = 0.038), and left ventricular ejection fraction, % (OR 0.97, 95% CI 0.94 to 0.99, p = 0.019) as independent risk factors for CIN.

CONCLUSIONS The IOCM iodixanol was significantly less nephrotoxic than ioxaglate, an ionic, dimeric LOCM. (The RECOVER Trial; http://clinicaltrials.gov; NCT00247325).