#537 Prevalence of functional iron deficiency and its impact on mortality in hemodialysis patients in Hatay

Abstract Background and Aims Chronic kidney disease (CKD) is a major public health concern that has become an epidemic both globally and in our country. Iron deficiency and functional iron deficiency (FID) are common among CKD patients. The aim of our study is to investigate the prevalence of FID and its impact on mortality in hemodialysis (HD) patients. Method Our study was conducted between 2010 and 2024 in patients undergoing hemodialysis in Hatay province. Patients included were those aged 18 and above who had been on HD for at least three months and had accessible records of serum iron, total iron-binding capacity, and ferritin levels. Patients undergoing home HD, peritoneal dialysis, and those under the age of 18 were excluded. The prevalence of anemia, absolute iron deficiency (AID), and functional iron deficiency (FID) was calculated, and their relationships with mortality were evaluated. Results A total of 3.086 HD patients were included in the study. The prevalence of FID was found to be 14.7%, and AID was 4.1%. Five-year survival rates based on iron deficiency status were 44.1% for FID, 58% for AID, and 54.2% for normal patients. Mortality was higher in functional iron deficiency than in other groups (P < 0.05). The mortality rate in patients with absolute iron deficiency was lower compared to other groups, but no statistical difference was observed compared to normal patients. Patients with transferrin saturation <20% had a statistically significantly higher mortality risk than those with transferrin saturation between 20%–30% and 30%–50%. There was no statistical difference between ferritin levels and mortality. However, the lowest mortality rate was observed in individuals with ferritin levels <300 µg/L, and the highest mortality rate was observed in those with ferritin levels >800 µg/L. The highest mortality risk was observed in patients with Hb levels < 8g/dL. Patients with Hb levels >10 g/dL had lower mortality risk. The highest mortality risk was observed in patients with Hb levels <8 g/dL. Patients with Hb levels >10 g/dL had lower mortality risk (P < 0.001). Conclusion Anemia is common in HD patients. We identified an FID prevalence of 14.7%, with mortality risks higher in FID compared to normal and AID patients. Patients with transferrin saturation <20% had a statistically significantly higher mortality risk. These results suggest that clinicians should focus more on transferrin saturation rather than ferritin in HD patients.