PRESSOR EFFECT OF RECOMBINANT-HUMAN-ERYTHROPOIETIN - RESULTS OF AMBULATORY BLOOD-PRESSURE MONITORING AND HOME BLOOD-PRESSURE MEASUREMENTS

We investigated whether treatment of anemic hemodialysis patients with a low dose of recombinant human erythropoietin (erythropoietin) for a short period would increase their blood pressure. Ambulatory blood pr essure monitoring and home blood pressure measurements were used to de tect minute increase in blood pressure. Thirty-two patients with a hem atocrit of 25% or less received erythropoietin at the dose of 4500 IU/ week, by the intravenous route for 8 weeks. Erythropoietin increased t he hematocrit from 20.9 +/- 2.1 to 26.2 +/- 2.1%. Erythropoietin eleva ted mean ambulatory blood pressure by 5 mmHg or more in two-thirds of patients (n=20; presser group), while it elevated home mean blood pres sure by 5 mmHg or more in one-third of patients (n=11). An increase in clinic mean blood pressure by more than 5 mmHg was observed only in o ne-fourth of patients (n=7). Circadian variation of blood pressure (no cturnal fall and diurnal rise) had been attenuated in the patients of the presser group before erythropoietin treatment and erythropoietin d ecreased the nocturnal fall of blood pressure further more. Erythropoi etin elevated nocturnal blood pressure more than diurnal blood pressur e. Therefore, the increase in blood pressure induced by erythropoietin was detected more reliably by ambulatory blood pressure monitoring. T here was no relation between the change in hemoglobin concentration an d the increase in ambulatory blood pressure induced by erythropoietin. Erythropoietin tended to decrease cardiac output and plasma volume wh ile it increased total peripheral resistance. It also decreased plasma norepinephrine and vasopressin levels but. did not affect other humor al factors. Although the presser effect of erythropoietin treatment fo r 8 weeks at the dose of 4500 IU/week was not evident on clinic blood pressure measurements, any increase in blood pressure determined by am bulatory blood pressure should be treated carefully to reduce the risk of a cardiovascular complication in patients receiving hemodialysis.