Background/aims: Anemia is common in patients with chronic kidney disease (CKD). Recently, the erythropoiesis-stimulating agent/hemoglobin level (ESA/Hb) index emerged as a new factor associated with increased morbidity and mortality in this population. In this study, we evaluated the factors that influence the ESA/Hb index in a pre-dialysis CKD population.
Methods: Ninety-five patients were evaluated for clinical and laboratory parameters, nutritional status and ESA/Hb index. For comparison, we divided our population into 3 groups: G I--no ESA treatment, G II--patients with ESA/index below 50th percentile and G III--patients with ESA/Hb index above 50th percentile. We performed single and multiple regression models and logistic regression analysis.
Results: In a multiple regression model, age (t = -3.456, P = 0.001), SGA (t = 2.059, P = 0.047), ferritin (t = 2.386, P = 0.027), Ca × P (t = 2.066, P = 0.043), TNF-α (t = 2.673, P = 0.009) and IL-6 (t = 2.939, P = 0.004) independently influenced the ESA/Hb index. At logistic regression analysis, gender, cardiovascular disease and TNF-α were independently associated with ESA/Hb higher than 50th percentile compared to the other patients (R(2) = 0.457).
Conclusion: In a pre-dialysis population, female gender, cardiovascular disease, malnutrition and inflammation are associated with a higher ESA/Hb index.