Role of Ferric Citrate in Hyperphosphatemia and Iron Deficiency Anemia in Non Dialysis CKD Patients

Abstract

Introduction: Disorders of mineral and bone metabolism in chronic kidney disease (CKD) are associated with increased risk for cardiovascular calcification and osteoporosis. Anemia has been associated with progressive loss of kidney function and increased mortality. Ferric citrate was recently developed, primarily as a novel oral, non-calcium phosphate binder, which has also shown to replenish the iron deficient state of the CKD patients.

Material and methods: This prospective study was done on 40 pre-dialysis adult patients of CKD (stage 3-5) from a tertiary care centre in North India. Patients on intravenous iron, erythropoietin stimulating agents or other phosphate binders were excluded from the study. All the patients were given tablet ferric citrate (each tablet containing ferric citrate 1.1 gm equivalent to ferric iron 210 mg) in a dose of 3 tablets per day for three months. Patients were followed up at two weekly intervals and relevant investigations were done. They were divided into three groups according to their CKD stages for subgroup analysis.

Observations: After three months of therapy with ferric citrate there was a significant decrease in mean serum phosphate from 6.55±0.70 mg/dl at baseline to 4.36±0.50 mg/dl at the end of three months (p<0.001). Mean hemoglobin increased from 7.92±1.05 g/dl at baseline to 10.96±1.04 g/dl at the end of three months (p<0.001). Serum ferritin and serum transferrin saturation increased from 278.25±110.56 ng/dl, 25.02±4.03 % at baseline to 401.24±152.47 ng/dl and 29.62±3.77 % at the end of three months. The mean serum vitamin D and serum iPTH levels, at baseline and at the end of 3 months were 14.61±10.80 ng/ml, 509.48±210.75 pg/ml and 23.65±14.00 ng/ml, 424.14±173.18 pg/ml respectively. The change in all these parameters were significant irrespective of the CKD stages.

Conclusion: The present study has shown that ferric citrate is an effective and well tolerated phosphate binder, which also significantly improves hematologic parameters in an iron deficient CKD patient.