Acute Effects of Iron Sucrose and Iron Carboxymaltose on Endothelial Function in Nondialysis Chronic Kidney Disease Patients

Intravenous iron is commonly prescribed in chronic kidney disease (CKD) patients. Iron sucrose (IS) and ferric carboxymaltose (FCM) are 2 frequently used formulations. Experimental data showed that this 2 intravenous iron preparations have different potential to induce oxidative stress and by that endothelial dysfunction. Still, direct comparisons in clinical settings are rather scarce.Are there any acute changes in endothelial function after single intravenous iron infusions of IS and FCM in nondialysis CKD patients?This was a prospective, crossover study in which 31 patients with CKD stages 3-5 (80% stages 3 and 4, 81% female, 55% older than 60 years, 23% diabetes mellitus, and 94% arterial hypertension) who required intravenous iron as part of their routine medical care were enrolled.The effect of flow-mediated vasodilatation infusions containing 250-mL 10% glucose, 500-mg FCM, and 200-mg IS, both in 250-mL 0.9% saline solution, was compared. The infusions were administered over 30 minutes, 72 hours apart, in the mentioned order. Ultrasound measurement of the brachial artery flow-mediated vasodilation (FMD) performed 15 minutes before and after each infusion was used to assess endothelial function. The outcome was the post/preinfusion difference (Δ) in FMD.The baseline FMD was similar before each study intervention. The arterial reactivity significantly decreased only after IS infusion [ΔFMD -2.3 (-5.65 to -0.33) vs. 1.0 (-1.49 to 1.80) after glucose, P = 0.01], but not after FCM [ΔFMD -0.8 (-2.50 to 0.65), P = 0.27 vs. glucose]. Moreover, the arterial reactivity was higher after IS as compared to FCM.Endothelial dysfunction seems to be acutely induced by a single dose of intravenous IS, but not by FCM, in nondialysis CKD patients.