Factors Related to Erythropoietin Hyporesponsiveness in Peritoneal Dialysis Patients with Anemia

Anemia in peritoneal dialysis (PD) patients can be improved after treatment with erythropoietin (EPO). However, several factors previously reported can cause EPO hyporesponsiveness including nutritional deficiency, infection or inflammation, secondary hyperparathyroidism with bone marrow fibrosis, angiotensin converting enzyme inhibitor (ACEI) administration, and dialysis inadequacy. Correction of these factors may lower doses and costs of EPO for these patients.

To calculate the prevalence of EPO hyporesponsiveness and the associated factors in PD patients with anemia.

We reviewed medical records of 195 PD patients who received EPO treatment during January 2000 to June 2013.The doses of EPO were titrated maximally to 8,000 U/week to maintain a target Hematocrit (Hct) level between 33% and 36%. PD patients Hct less than 30% before and after EPO administration for 3 months were included in this study. There were 44 patients who were recruited by the criteria. They had no history of bleeding or red cell transfusions within 2 months. The EPO resistance index (ERI) was calculated as weekly EPO doses per Hct levels per kilograms body weight (kg). The EPO hyporesponsiveness was defined as the weekly EPO doses was >150 U/kg. The relationship between the ERI and continuous parameters was calculated by the student’s t-test. Chi-square and Fisher’s exact correlation were performed to analyze the relationship between ERI and categorical variables. The p-value <0.05 was considered statistically difference.

There were 13 (6.7%) patients having Hct less than 33% after the administration EPO >150 U/kg/week for 3 months. The statistically significant relationship between ERI and gender was detected. Female had higher rate of having EPO hyporesponsiveness (p = 0.02).

The prevalence of EPO hyporesponsiveness was 6.7%. Female gender was a factor related to EPO hyporesponsiveness in our study.