Serum Hepcidin and Iron Indices Affect Anemia Status Differently According to the Kidney Function of Non-Dialysis Chronic Kidney Disease Patients: Korean Cohort Study For Outcome in Patients with Chronic Kidney Disease (KNOW-CKD)

Abstract

Background/aims: No studies have examined the association among serum hepcidin, iron indices, or anemia status based on the kidney function of non-dialysis chronic kidney disease (CKD) patients.

Methods: We reviewed data of 2238 patients from a large-scale multicenter prospective Korean study (2011-2016) and excluded 198 patients with missing data regarding serum hepcidin, hemoglobin, transferrin saturation (TSAT), ferritin, and usage of erythropoiesis-stimulating agents (ESA) or supplemental iron and 363 patients using ESA or supplemental iron. Finally, 1677 patients were included.

Results: The mean patient age was 53.5 years, and 65.4% were men. TSAT and serum hepcidin were significantly associated with anemia status, whereas serum ferritin was not, regardless of anemia severity. For patients with an estimated glomerular filtration rate (eGFR) ≥45 mL/min/1.73 m2, a 10% increase of TSAT was associated with hemoglobin <13 g/dL (odds ratio [OR], 0.628; 95% confidence interval [CI], 0.515-0.765; P<0.001) and hemoglobin <11.5 g/dL (OR, 0.672; 95% CI, 0.476-0.950; P=0.024), whereas a 10-ng/mL increase of serum hepcidin was associated with hemoglobin <11.5 g/dL (OR, 1.379; 95% CI, 1.173-1.620; P<0.001) and hemoglobin <10.0 g/dL (OR, 1.360; 95% CI, 1.115-1.659; P=0.002) for patients with eGFR <45 mL/min/1.73 m2 according to multivariate logistic analysis.

Conclusions: TSAT was associated with less severe anemia in early CKD patients. Serum hepcidin was associated with more severe anemia in advanced CKD patients.

Keywords: Anemia; Ferritin; Hepcidin; Severity; Transferrin saturation.