Evaluation of clinical characteristics and treatment appropriateness in patients receiving intravenous iron therapy

Abstract Intravenous (IV) iron is frequently used to treat iron deficiency, even though oral iron therapy is recommended as a first-line treatment in most cases. IV therapy provides various benefits but also has drawbacks, including high costs, potential allergic reactions, and the need for hospitalization. In this study, we assessed patient and disease-related factors of IV iron therapy and re-evaluated treatment appropriateness using an algorithm created by reviewing current guidelines and literature. A retrospective single-center study evaluated the appropriateness of IV iron replacement in 264 outpatients between May 2 and October 15, 2023, at a tertiary care hospital. Threshold values for iron deficiency based on a review of many current guidelines Ferritin < 30 µg/L or (when CRP ≥ 5 mg/L, ferritin < 100 µg/L, and TSAT < 20%) were determined. Patients were reassessed for IV iron treatment appropriateness with an algorithm based on the history of oral iron use, patient/disease-related factors, and current guidelines. According to the algorithm, 81 patients (31%) who received IV iron treatment were not considered appropriate. Oral iron was not preferred in 74 patients (28%), and 7 patients (3%) were not evaluated as iron deficient. The rate of inappropriate treatment was higher in the group over 65 years of age (p = 0.03). Inappropriate treatment was much higher in the group without anemia (p < 0.001). We have observed that IV iron therapy is unnecessarily preferred in first-line treatment. New algorithms incorporating patient-related factors, current evidence, and clinical experience are needed.