Supplementary Material for: Contrast Media in Hospitalized Patients with Acute Kidney Injury - Renal and Clinical Outcomes

Introduction:
Acute kidney injury (AKI) is a common complication among hospitalized patients and is associated with substantial morbidity and mortality. Intravenous contrast media is frequently used in diagnostic imaging, but data on its safety in patients with established AKI remain limited. This study prospectively assessed renal and clinical outcomes following intravenous contrast administration in hospitalized patients with AKI

Methods:
In this prospective observational study, we included hospitalized adults diagnosed with AKI who underwent CT imaging with or without intravenous contrast between January 2023 and March 2024. The primary outcome was renal recovery within 7 days, defined as return of serum creatinine to baseline. Secondary outcomes included renal improvement within 72 hours, dialysis requirement after CT, length of stay, and in-hospital mortality.. Analyses were performed using inverse probability weighting(IPW), with propensity score matching (PSM) as a secondary robustness analysis.

Results:
A total of 481 patients were analyzed; 282 received contrast and 188 did not. After IPW adjustment, renal recovery within 7 days occurred in 61.7% of the contrast group vs. 47.3% of the non-contrast group (OR 1.7, 95% CI 1.0–2.97, p = 0.05). Secondary outcomes were similar between groups. Results were consistent in a secondary PSM analysis. In the overall cohort, higher AKI stage and acute tubular injury were independently associated with lower recovery odds.

Conclusion:
In hospitalized patients with AKI, intravenous contrast administration was not associated with worse renal or clinical outcomes, suggesting that contrast-enhanced CT may be acceptable in selected clinical settings.