Is intravenous administration of iodixanol associated with increased risk of acute kidney injury, dialysis, or mortality? A propensity score-adjusted study

Purpose: To compare the rates of acute kidney injury (AKI), emergent dialysis, and short-term mortality between patients who underwent intravenous administration of the iso-osmolar contrast material (IOCM) iodixanol 320 and patients who underwent a noncontrast computed tomography (CT) examination. Materials and Methods: Study design and implementation were overseen by an institutional review board and conformed to HIPAA guidelines on patient data integrity. All patients who underwent an iodixanol-enhanced (IOCM group) or a noncontrast (noncontrast group) CT examination from January 2003 to December 2014 were identified. Patients were subdivided into subgroups of those with stage 1-2 chronic kidney disease (CKD) (estimated glomerular filtration rate [eGFR], ≥ 60 mL/min/1.73 m²), those with stage 3 CKD (eGFR, 30-59 mL/min/1.73 m²), and those with stage 4-5 CKD (eGFR < 30 mL/min/1.73 m²) and separately underwent propensity score stratification and matching. Rates of AKI, emergent dialysis, and mortality were compared between IOCM and noncontrast groups. Additional analyses incorporating intravenous fluid administration, including additional CT studies at other sites within a single institution, and a paired analysis of patients who underwent both IOCM and noncontrast CT studies during the study time frame, were also performed. Results: A total of 5758 patients (1538 with stage 1-2 CKD, 2899 with stage 3 CKD, and 1321 with stage 4-5 CKD) were included in the study. After propensity score adjustment, rates of AKI, dialysis, and mortality were not significantly higher in the IOCM group compared with the noncontrast group for all CKD subgroups (AKI odds ratios [ORs], 0.74-0.91, P = .16-0.69; dialysis ORs, 0.74-2.00, P = .42-.76; mortality ORs, 0.98-1.24, P = .39-.88). Sensitivity analyses yielded similar results. Conclusion: Among patients at the highest perceived risk of postcontrast AKI, intravenous administration of iodixanol for contrast material enhanced CT was not an independent risk factor for AKI, dialysis, or mortality.