Effect of recombinant human erythropoietin treatment on blood pressure and some haematological parameters in healthy men

The aim of this study was to evaluate the effect of treatment with subcutaneous injections of recombinant human erythropoietin (rhEpo), 20-40 IU kg-1 body weight, 3 times a week, on resting blood pressure, blood pressure response during submaximal exercise, some haematological parameters, and subjective side-effects in 15 healthy male subjects. RhEpo increased both haemoglobin (Hb) concentration and haematocrit (Hct) significantly, the values for Hb being 152 +/- 4.2 g l-1 before treatment and 169 +/- 9.3 g l-1 (mean values +/- SD) after 6 weeks of rhEpo treatment (P less than 0.001). The corresponding values for Hct were 44.5 +/- 1.5% and 49.7 +/- 1.9% (P less than 0.001), respectively. The systolic and diastolic blood pressure values at rest were unchanged after rhEpo treatment. A marked increase in systolic blood pressure was observed during submaximal exercise at 200 W, the initial and final values being 177 +/- 14.2 mmHg and 191 +/- 19.5 mmHg (P less than 0.01), respectively. Heart rate during exercise at 200 W was significantly lower after rhEpo treatment than before it: 144 +/- 15 beats min-1 compared to 136 +/- 8 beats min-1 (P less than 0.001). The leucocyte count remained unchanged after rhEpo treatment, but there was a significant decrease (P less than 0.05) in the number of lymphocytes. Reticulocyte and platelet counts were unchanged. Serum (S) ferritin decreased from 87.3 +/- 41.8 mmol l-1 to 59.3 +/- 27.8 mmol l-1 after rhEpo treatment (P less than 0.001). Serum-Na, S-K, S-Ca, S-creatinine, S-bilirubin, S-aspartate aminotransferase (ASAT), S-alanine aminotransferase (ALAT), and S-lactate dehydrogenase (LD) were unchanged after rhEpo treatment. No subjective side-effects were reported. In conclusion, low doses of rhEpo increased Hb levels and Hct by more than 10% after 6 weeks. Blood pressure at rest was unchanged, but rhEpo induced a markedly accentuated blood pressure reaction during exercise. A minor decrease in the lymphocyte count was observed, but electrolyte and creatinine levels remained unchanged after rhEpo treatment.