Endocrine Abstracts

Introduction: Anemia is associated with an increased risk of cardiovascular events and death in patients with diabetic nephropathy (DN). However, there are still a lot of contradictions related to the benefits and risks of antianemic treatment in this group of patients due to variety of non-hematopoietic effects of erythropoietin. The aim of this study was to assess the influence of erythropoietin therapy on renal function and proteinuria in patients with early DN.

Methods: We included 36 patients with type 2 diabetes mellitus and early DN (chronic kidney disease, stages 1–3) complicated with renal anemia, not receiving hemodialysis. The main group (17 patients) received standard doses of erythropoietin-α s.c. and iron medication orally for 16 weeks. The control group (19 patients) received only oral iron medications for the same period of time. We assessed serum creatinine and urea levels, glomerular filtration rate (estimated by Cockraft–Gault formula) and urinary protein concentrations before and after 16 weeks of treatment. The Wilcoxon non-parametric test (W) was used to compare these values in study groups.

Results: Before treatment we found the following mean values in the main and the control group, respectively (P=0.05): serum creatinine – 118.7±10.1 and 115.4±8.8 μmol/l, serum urea – 11.2±0.9 and 10.7±0.6 mmol/l, estimated glomerular filtration rate – 65.5±5.2 and 63.1±6.9 ml/min*1.73 m², urinary protein concentration – 0.50±0.09 and 0.48±0.10 g/l. After 16 weeks of treatment estimated glomerular filtration rate, creatinine and urea levels have not undergone significant changes (P>0.1). At the same time mean urinary protein concentration has significantly decreased in the main group as compared to the control group – 0.29±0.05 and 0.50±0.11 g/l, respectively (W=2.90; P=0.004).

Conclusion: The results suggest that comprehensive antianemic therapy with erythropoietin and iron medications leads to a reduction of proteinuria level in anemic patients with early stages of DN. This beneficial effect can be taken in account when defining the indications for erythropoietin administration.