Anemia occurs in a significant minority of peritoneal dialysis (PD) patients despite unrestricted access to erythropoiesis-stimulating agents (ESAs) and intravenous iron, Brazilian researchers find.
Marisa Cristiane Cardoso de Oliveira, MD, of Federal University of São Paulo in Brazil and colleagues conducted a retrospective study of 120 PD patients from their dialysis unit. Most patients were middle-aged and had been on PD for 17 months (86% on automated PD). All had hypertension, and nearly a third had diabetes. Iron deficiency, defined as a transferrin saturation (TSAT) less than 20% or ferritin level less than 100 µg/L, was present in 35% of patients. All received intravenous iron at the dialysis unit. Subcutaneous administration of erythropoiesis-stimulating agents (ESA) was indicated for 87.5% of patients.
Anemia, defined as a hemoglobin level less than 11 g/dL, occurred in 28% of patients, according to results published in Brazilian Journal of Nephrology. Anemic patients received higher doses of iron and had lower concentrations of triglycerides. Hemoglobin levels were negatively associated with both iron and ESA doses. Hemoglobin positively correlated with albumin, triglycerides, and TSAT. After multivariate analysis, only albumin and ESA dose were independently associated with hemoglobin.
The investigators speculate that poor ESA adherence may have contributed to anemia since subcutaneous ESA administration needed to be performed at home by patients and was not checked by healthcare workers. ESA doses also differed, which would lead to variable hemoglobin levels.
Poor nutrition also may have played a role in anemia. About half of patients had low albumin levels, which the researchers believed indicated malnutrition and inflammation. Triglycerides have been linked to malnutrition, and the new study found a correlation between albumin and triglyceride levels.
Among the study’s limitations, the investigators acknowledged that they did not have information on other inflammatory markers or indicators of nutrition status.