Association of FGF23 Levels and Development of Anemia in Patients with Non Dialysis Chronic Kidney Disease

Background: Anemia is one of the common complication of Chronic Kidney Disease that intensifies in grade and severity as eGFR decline which also increases the risks for cardiovascular mortality. The development of anemia and elevated fibroblast growth factor 23 levels are the earliest changes observed in chronic kidney disease. Objective: This study aims to understand the association of FGF23 levels development of anemia in chronic kidney disease patients prior to renal replacement therapy. Methods: This is an analytical type of cross sectional study carried out among 95 respondent'1ged between 18 and 75 years with CKD stage 1-5 before dialysis, divided into two groups- Group I­ comprised of 68 patients and Group 11- included 27 age and sex matched respondents not having CKD, enrolled from two te1tiary-care hospitals, namely- Sir Salimullah Medical College & Mitford Hospital and National Institute of Kidney Diseases & Urology (NIKDU). Socio-demographic status, disease profile and laboratory findings including serum iron, iron binding capacity, ferritin, transferrin saturation, calcium, phosphorus, intact parathormone, vitamin D, eGFR and FGF-23 levels were studied. Result: Mean age of the respondents was 50.1±10.74 (SD) years, mean estimated glomerular filtration rate was 35.92± 22.61 in group I and 91.66± 14.2 in group II. The mean FGF23 level in group I and II were 85.76± 207.54, 21.99± 12.12 pg/mL respectively, serum iron level was 81.61± 39.24 mcg/dL and 95.0± 32.38 mcg/dL in group I and II respectively, serum ferritin level was 225.59± 2 I 2.5 ng/mL and 157.85± 220.89 ng/ml. TIBC was 312.65± 95.83 mcg/dL and 418.85± 118.25 mcg/dL in group I and II respectively. In Group I and II, iron deficiency was found in 23% and 25%respectively when stratified according to serum ferritin level and 26.5% and 22.22% respectively, when stratified according to serum transferrin saturation level. This difference was significant among the group. Serum iron, ferritin, TIBC and TSAT were significantly associated with serum FGF23 levels. Conclusion: Disrupted iron metabolism and high FGF23 levels is commonly found in chronic kidney disease. Clinical laboratory findings have revealed the relation between FGF23 and anemia in no dialysis chronic kidney disease patients.