Abstract: TH-PO913
Cutoff Value of Erythropoiesis-Stimulating Agent Resistance Index at Which Iron Replacement Therapy Is Expected to Be Effective
Session Information
- Anemia and Iron Metabolism
October 24, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Anemia and Iron Metabolism
- 200 Anemia and Iron Metabolism
Authors
- Ogawa, Chie, Maeda Institute of Renal Research, Kawasaki, Kanagawa, Japan
- Tsuchiya, Ken, Department of Blood Purification, Tokyo Women’s Medical University, Tokyo, Japan
- Morito, Taku, Maeda Institute of Renal Research, Kawasaki, Kanagawa, Japan
- Io, Hiroaki, Juntendo Nerima Hospital, Tokyo, Japan
- Maeda, Kunimi, Maeda Institute of Renal Research, Kawasaki, Kanagawa, Japan
Background
Erythropoiesis stimulating agents (ESAs) in the treatment of renal anemia have provided tremendous long-term success, but the current problem is resistance to them. A number of causative factors can be cited, but the biggest concern is the issue of iron supply for iron deficiency and the lack of a useful iron indicator. Therefore, we investigated ESA resistance index (ERI) levels and the effects of oral iron replacement therapy (OIRT) in hemodialysis (HD) patients.
Methods
This study involved 81 courses in 67 HD patients with CRP< 0.3mg/dL who received OIRT. OIRT was performed for patients with serum ferritin <60 ng/mL and Hb <12 g/dL and continued for at least seven months(M7). The dose of darbepoetin alfa (DA) was adjusted to a target Hb level of 10–12 g/dL in accordance with the Japanese guidelines. The relationship of efficacy to changes in erythrocyte- and iron-related factors as well as baseline (M0) data was examined. Effective group was when (1) Hb increased by ≥1 g/dL or to >12 g/dL without an increase in DA, and (2) the DA dose was decreased. ERI＝Weekly DA dose (μg)x 200/Hb level (g/dL)/body weight(kg).
Results
There were no significant differences in erythrocyte- and iron-related factors between the effective and ineffective groups at M0, and only the ERI was significantly higher in the effective group (9.0±7.6 vs 4.0±2.5, p=0.01). ROC curve analysis with efficacy as the endpoint showed a ERI cut-point value of ≥7.8 (sensitivity; 51.5%, specificity; 93.3%, AUC; 0.78, 95% CI; 0.66–0.90). In patients with an ERI ≥ 7.8, there were only 1 invalid cases. ERI showed significant monthly decreases down from M1 to 4 and maintained a constant value thereafter in effective group, whereas no significant change in ineffective group, and ERI was no significant difference between the groups at M7(4.9±3.8vs 3.8±2.8, p=0.32,). In effective group, red blood cell (RBC) counts and mean hemoglobin content (MCH) showed a significant increase. Serum ferritin significantly elevated at similar levels in both groups.
Conclusion
This study showed a decrease in ERI, and an increase in RBC and MCH in the effective group, suggesting that the proliferation of RBC and the production of hemoglobin were suppressed due to iron deficiency. Thus, iron replacement therapy may be effective in HD patients with CRP<0.3mg/dL and ERI≥7.8.
Funding
- Private Foundation Support