Is intravenous iodinated contrast medium administration really harmful in hospitalized acute kidney injury patients: a propensity score–matched study

Objectives To evaluate the effects of intravenous iodinated contrast medium (ICM) administration on the deterioration of renal function (DRF), new renal replacement therapy (RRT) induction and mortality of hospitalized acute kidney injury (AKI) patients. Methods Adult hospitalized patients undergoing a contrast-enhanced or unenhanced CT scan within 7 days after AKI diagnosis from January 2015 to December 2019 were identified in this retrospective study. Propensity score matching was performed. Outcomes in 7 and 30 days after CT scan were compared between the contrast and non-contrast groups. Additional analyses were also performed in patients stratified by SCr levels at AKI diagnosis, times and time of CT scan, and in patients without chronic kidney disease or RRT requirement prior to CT scan. Results In total, 1172 pairs were generated after 1:1 propensity score matching from 1336 cases exposed to ICM and 2724 unexposed. No significant differences were found in the outcomes between the two groups: DRF, 7.8% vs 9.0% (odds ratio (OR) 0.83, 95% confidence interval (CI) 0.62–1.11) in 7 days, 5.1% vs 5.4% (OR 0.93, 95%CI 0.64–1.34) in 30 days; new RRT induction, 2.3% vs 3.3% (OR 0.72,95%CI 0.43–1.18) in 7 days, 4.2% vs 4.5% (OR 0.95,95%CI 0.64–1.41) in 30 days; and mortality, 3.9% vs 4.8% (OR 0.83,95%CI 0.56–1.22) in 7 days, 9.0% vs 10.2% (OR 0.88,95%CI 0.68–1.15) in 30 days. Subset analyses showed similar results. Conclusion Intravenous ICM administration during AKI duration did not increase the risks of DRF, new RRT induction, and mortality in 7 and 30 days after CT scan. Key Points • Intravenous ICM administration in hospitalized AKI patients does not increase the risks of deterioration of renal function, RRT induction, and mortality in 7 and 30 days after CT scan. • The effects of intravenous ICM on adverse outcomes are minimal even in AKI patients with high level of SCr values or multiple CT scans.