Influence of erythropoietin on blood pressure in continuous ambulatory peritoneal dialysis patients

Abstract

To assess the effect of erythropoietin (EPO) treatment on blood pressure in continuous ambulatory peritoneal dialysis (CAPD) patients, we analyzed in a retrospective study the results of 6 months of EPO treatment in 17 CAPD patients. There were 10 females and 7 males, mean age 52 years, mean duration on CAPD 35 months. They received subcutaneously a mean initial EPO dose of 114±45 U/kg/week (range 59-209). This dose was adjusted throughout 6 months to achieve and maintain a target Hb of 100 g/L (Hct 30%). Seven of the patients were hypertensive before starting EPO treatment. Fifteen patients (88.2%) achieved the target hemoglobin. For all subjects (n=17) there was a significant increase in lying mean blood pressure (MBP) from 93.8±10.0 to 105.2±14.4 mmHg (p=0.0024). Four patients required an increase in their antihypertensive medication, and 4 were not treated before we started antihypertensive treatment (Group I). This group represents 46% (8/17) of the patirnts. There was no change in the antihypertensive medication status of the remaining 9 patients (Group II). The baseline lying MBP was not significantly different for the two groups (98.8±9.8 mmHg vs 96.1±7.2 mmHg). The mean weekly dose of EPO during the first 3 months was higher in Group I(126 vs 100 U/kg) and conversely was lower during the last 3 months (mean dose 108 vs 117 U/kg). Patients of Group I were younger (mean age 47 vs 56 years), had a lower body weight at the time of EPO start (55 vs 66 kg), a higher increase of Hb during the first 2 months (28.8 vs 20.8 g/L), and reached the target Hb sooner (2.25 vs 4.0 months). A comparison group of 17 patients (matched for age, sex, duration on CAPD, underlying disease and antihypertensive treatment) who did not receive EPO did not show an increase in MBP over time, and only 2 patients increased their antihypertensive medication. Our data suggest that higher initial EPO doses may be accompanied by hypertension changes in CAPD patients. This may be prevented by a lower initial dose and lower rates of increase of Hb and Hct.