The Impact of Postoperative Intravenous Iron Therapy on Clinical Outcomes in Surgical Patients with Iron-Deficiency Anemia: A Comparative Analysis by Frailty Status in the Setting of Elective Cardiac Surgery

Background and objectives: To comparatively investigate the impact of postoperative intravenous iron therapy (IVIT) as add-on to preoperative IVIT on clinical outcomes in frail versus non-frail patients with iron deficiency anemia (IDA) in the setting of elective cardiac surgery. Materials and methods: This was a retrospective single-center study. The data was collected prospectively between January 2021 and November 2024. 200 patients with IDA (100 frail and 100 propensity score matched non-frail patients) who received IVIT before and/or after elective cardiac surgery were included. Patients were divided into four equal groups including frail-pre/post group (frail patients with preoperative plus postoperative IVIT), non-frail-pre/post group (non-frail patients with preoperative plus postoperative IVIT), frail-pre group (frail patients with preoperative IVIT) and non-frail-pre group (non-frail patients with preoperative IVIT). Perioperative parameters, postoperative complications, length of hospital stay (LOS) were recorded in each group. Postoperative follow-up parameters included change in hemoglobin levels and reticulocyte count from baseline (on operation day, postoperative day 1, day 7, 1st month and 3rd month) as well as the hospital readmission and mortality rates within 3 months after surgery. Results: Hemoglobin levels (10.6±1.2 g/dL at baseline to 12.6±1.4 g/dL at 1st month and 13.4±1.4 g/dL at 3rd month, p=0.01 and p=0.02) and reticulocyte counts (0.035±0.005 x1012/L at baseline to 0.075±0.005 x1012/L at 1st month and 0.085±0.005 x1012/L at 3rd month, p=0.004 and p=0.002) were significantly improved from baseline only in the frail-pre/post group. Conclusions: Postoperative IVIT demonstrated improved postoperative hemoglobin levels and reticulocyte counts, besides its potential in reducing perioperative transfusions, in the setting of elective cardiac surgery in frail patients with IDA.