The relationship between erythropoietin therapy and nutritional parameters in dialysis patients

Background and aims: Malnutrition is a common condition in patients with end-stage renal disease (ESRD), which adversely affects the quality of life and is also associated with increased mortality and morbidity. Additionally, another concomitant medical problem in patients with ESRD is anemia. In patients with chronic kidney disease (CKD), usually decreased erythropoiesis due to erythropoietin (EPO) deficiency results in anemia. Therefore, erythropoietin replacement is one of the most important treatment modalities in patients with CKD. Since anemia also contributes to the development of malnutrition in patients with ESRD, anemia treatment also improves malnutrition. In this study, we aimed to investigate the relationship between EPO treatment and nutritional parameters in patients receiving dialysis treatment. Materials and methods: The study was performed with dialysis patients receiving EPO treatment and followed up with ESRD in Department of Nephrology, Zonguldak Bulent Ecevit University, Faculty of Medicine between October 2016 and October 2018. 43 patients, 17 females and 26 males, who underwent hemodialysis (HD) 3 times a week and 7 patients, 4 females and 3 males, who underwent continuous ambulatory peritoneal dialysis (CAPD) were included. Nutritional status of these patients was evaluated with biochemical parameters and using Malnutrition inflammation score (MIS). Patients included in our dialysis program who used regular EPO for two years, without any malignant disease, severe liver disease, decompensated heart failure, advanced lung disease or any disease that would cause immobilization, had no history of major surgery during their follow-up. Results: In our study, a positive correlation was found between MIS and comorbidity, CRP, loss of appetite and dry weight, however there was a negative correlation between MIS points and albumin levels. There were no significant correlation between MIS points and the administration of EPO duration, dialysis duration and age. There was no significant change in laboratory tests during two years of EPO treatment. Only HDL and uric acid levels showed a significant decrease. After two years of EPO treatment, it was observed that the number of patients without malnutrition increased. Hemoglobin levels were significantly increased with EPO treatment. After treatment, ferritin and transferrin saturation also increased significantly (p<0.05). Conclusion: The decrease in the percentage of malnourished patients after EPO treatment can be explained by the decrease in calculated MIS with the increase in functional capacity, increased appetite, and increased dietary intake, resulting in decreased weight loss and increased weight gain as a consequent of improvement anemia in patients. The absence of significant changes in laboratory parameters may be related to the influencing of laboratory parameters by many factors such as age, gender, inflammation, and dialysis efficiency. While the percentage of patients with malnutrition decreases, no significant changes in laboratory parameters support the opinion that nutritional evaluation should not be performed only with laboratory parameters as suggested in many studies. Further research is needed to fully elucidate the relationship between EPO therapy and nutritional parameters in dialysis patients. Key Words: End-stage renal disease, malnutrition, malnutrition inflammation score, erythropoietin