The impact of withdrawing ACE inhibitors on erythropoietin responsiveness and left ventricular hypertrophy in haemodialysis patients

Background. Aagiotensin-converting enzyme (ACE) inhibitors have the capabil ity of decreasing left ventricular mass index (LVMI) in chronic haemodialys is (HD) patients. On the other hand, recent reports provide conflicting inf ormation regarding the impact of ACE inhibitors on responsiveness to recomb inant human erythropoietin (rHuEpo), and there are no data about the effect of withdrawing ACE inhibitors both on rHuEpo response and LVMI in HD patie nts. Methods. ACE inhibitors were switched to another antihypertensive medicatio n in 23 out of 68 patients in our HD unit who were receiving both rHuEpo an d an ACE inhibitor for more than 1 year. Blood pressure at the pre- and pos t-dialysis phases, haematocrit levels and rHuEpo doses were determined at t he end of the first and of the third years, and the LVMI was determined at the end of the third year. Statistical analyses were done in 15 patients in whom the study could be completed. Results. The mean (+/- SD) haematocrit level was increased from 26.3 +/- 6. 4% to 29.8 +/- 6.3% at the first year (P < 0.05), and to 29.4 +/- 6.5% at t he third year (P < 0.05 vs before), while the mean dose of rHuEpo was decre ased from 208.3 +/- 99.0 UI/kg/week to 141.0 +/- 91.8 at the first year (P = 0.01), and to 141.4 +/- 81.0 at the third year (P = 0.01 vs before). Admi nistration of rHuEpo had been stopped in two patients at the end of the fir st year. The mean blood pressure level and the mean LVMI were not changed ( P > 0.05 vs before). There were no significant changes in dialysis paramete rs, iron status, plasma renin activities, and levels of aldosterone, intact parathyroid hormone, aluminum and erythropoietin. Conclusion. The findings of this small uncontrolled study indicate that wit hdrawal of BCE inhibitors in hypertensive chronic HD patients receiving rHu Epo may result in an increase in haematocrit level, and a decrease in dose of rHuEpo without any significant changes in the blood pressure level and L VMI. Controlled prospective studies are needed to clarify this issue.