IV Contrast Use During AKI Is Not Associated with Adverse Kidney Outcomes: A Retrospective Cohort Study of 30,000 Patients

Background: Acute kidney injury (AKI) is a common complication in hospitalized patients and is associated with increased morbidity and progression to chronic kidney disease (CKD). The nephrotoxicity of intravenous (IV) contrast during AKI remains controversial, with limited real-world data to guide clinical decision-making. This study evaluates whether IV contrast administration during AKI is associated with adverse renal outcomes. Methods: This retrospective cohort study utilized data from patients hospitalized at Loma Linda University Health between 2010 and 2023. Patients with AKI were identified using ICD codes, and AKI resolution was determined by KDIGO criteria. The primary outcome was AKI resolution at discharge. Secondary outcomes included progression to new CKD Stage 5 and CKD stage worsening at 6 months. Multivariable logistic regression and 1:1 propensity score matching (PSM) were used to adjust for confounders including demographics, comorbidities, and illness severity (approximated by ICU admission and ICU days). Results: Among 30,219 patients with AKI, 1,825 (6.0%) received IV contrast. Contrast use was not associated with lower odds of AKI resolution at discharge (aOR = 1.00; 95% CI: 0.90–1.10; p = 0.93), nor with increased risk of new CKD Stage 5 at 6 months (aOR = 0.87; 95% CI: 0.73–1.04; p = 0.13) or CKD stage worsening (aOR = 1.35; 95% CI: 0.87–2.09; p = 0.19) at 6 months. Findings remained consistent in PSM analysis. Subgroup analyses by AKI stage, baseline CKD stage, and age showed no negative effect of IV contrast administration during AKI on renal outcomes. Conclusion: In this large cohort study, IV contrast use during AKI was not independently associated with adverse renal outcomes. These findings may help reassure clinicians when contrast-enhanced imaging is clinically indicated in those with AKI.